Document KR8RZg3G9O7vdvVgXLex22NEo

19 of 30 A R S - \So3 C-8 DATA SUMMARY REPORT CONSENT ORDER GWR-2001-019 DuPont Washington Works Facility and Local, Letart And Dry Run Landfills February 2003 Project No. 7423 18983635 Prepared by t j ON NIVlNQQ CORPORATE REMEDIATION GROUP An Alliance between DuPont and URS Diamond Barley Mill Plaza, Building 27 Wilmington, Delaware 19805 000008 OEPA 4053 DuPont Engineerifig Barley M ill Plaza i Bldg, 27 Lancaster Pika & Rte. 141 Wilmington, DE 19805 DuPont Engineering February 5,2003 David P. Watkins West Virginia Department of Environmental Protection Division of Water Resources 1201 Greenbrier Street Charleston, West Virginia 25311-1088 FEB - 6 2003 RE: C-8 Data Summary Report Consent Order GWR-2001-019 Dear Mr. Watkins: DuPont is pleased to submit this C-8 Summary Report for the Washington Works facility, associated landfills and offsite areas in order to satisfy the remaining GIST requirements of the Multi-Media Consent Order. This report consists of seven sections. An introduction is presented Section 1. C-8 analysis and reporting are discussed in Section 2. A summary of the investigations conducted and results generated for the Washington Works facility, Local Landfill, Letart Landfill, and Dry Run Landfill are presented in Sections 3 through 6, respectively. References are cited in Section 7. This report is comprehensive. It summarizes all work performed and includes all sampling results generated through November 2002. For each main area investigated, C-8 analytical results are summarized and compared to the Screening Levels established by the CATT. Additionally, an exposure assessment was performed for the areas investigated to identify whether human or ecological exposure pathways were complete. If during your review of this document, you have questions or comments, please feel free to contact me at (302) 992-6820. I look forward toward seeing you at the next GIST meeting scheduled for February 19, 2003. Andrew S. Hartten Project Director cc GIST Members Ann Bradley-Spillman Thomas & Battle Andrea Malinowski -DuPont Legal Project File . I. du Pont de Nemours and Company OOOOC9 EN-3980 Rev. 3/2000 C-8 DATA SUMMARY REPORT CONSENT ORDER GWR-2001-019 DUPONT WASHINGTON WORKS FACILITY AND LOCAL, LETART AND DRY RUN LANDFILLS Date: February 2003 Project No.: 7423 18983753.00036 CORPORATE REMEDIATION GROUP An Alliance between DuPont and URS Diamond Barley Mill Plaza, Building 27 Wilmington, Delaware 19805 000040 C-8 Data Summary Report Table of Contents TABLE OF CONTENTS Executive Summary....................................................................................................... viii 1.0 Introduction...............................................................................................................1 1.1 Document Organization....................................................................................3 2.0 C-8 Analyses and Analytical Reporting.....................................................................4 2.1 Independent Quality Assurance Review...........................................................5 3.0 Washington Works Facility........................................................................................7 3.1 Introduction.......................................................................................................7 3.2 Task A: Groundwater Well and Water-Use Surveying and C-8 Sampling........................................................................................................... 7 3.2.1 One-Mile Radius Sampling.................................................................7 3.2.2 Two-Mile Radius Sampling.................................................................8 3.2.3 Ohio One-Mile Sampling....................................................................9 3.2.4 Ohio Two Mile Sampling....................................................................9 3.3 Task B: Assessment of Existing Groundwater and Surface-water Monitoring Data.............................................................................................. 10 3.3.1 Monitoring of C-8 in Groundwater and Surface Water..................... 10 3.3.2 Ohio River Water Quality.................................................................. 12 3.3.3 Public Water Supply Sampling.......................................................... 13 3.4 Task C: Plume Identification/Groundwater Assessment................................ 14 3.4.1 Installation of New Wells at the Washington Works Facility........... 14 3.4.2 Hydrogeologic Testing of New Wells at the Washington Works Facility.................................................................................... 14 3.4.3 Washington Works Groundwater Model Refinement....................... 15 3.4.4 Surface-water Field Reconnaissance at the Washington Works Facility............................................................................................... 15 3.4.5 C-8 Monitoring in Groundwater and Surface Water at the Washington Works Facility...............................................................15 3.4.6 Washington Works Facility Site Conceptual Model Refinement......................................................................................... 16 3.5 Revised Site Conceptual Model......................................................................16 3.5.1 Current Environmental Setting..........................................................16 3.5.2 Current Human Health and Ecological Exposure Pathways.............21 3.6 Washington Works Facility Summary........................................................... 24 4.0 Local Landfill.......................................................................................................... 26 4.1 Introduction..................................................................................................... 26 4.2 Task A: Groundwater Well and Water-Use Surveying and C-8 Sampling......................................................................................................... 26 4.3 Task B: Assessment of Existing Groundwater and Surface-water Monitoring Data........................... 27 WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE O O O O ll i C-8 Data Summary Report Table of Contents 4.3.1 Monitoring of C-8 in Groundwater and Surface Water....................27 4.4 Task C: Plume Identification/Groundwater Assessment................................28 4.4.1 C-8 Monitoring in Groundwater and Surface Water at Local Landfill..............................................................................................28 4.4.2 Surface-water Field Reconnaissance at the Washington Works Facility...............................................................................................29 4.4.3 Installation of New Wells at Local Landfill......................................29 4.4.4 Local Landfill Site Conceptual Model Refinement...........................29 4.5 Revised Site Conceptual Model......................................................................29 4.5.1 Current Environmental Setting..........................................................29 4.5.2 Current Human Health and Ecological Exposure Pathways.............34 4.6 Local Landfill Summary.................................................................................36 5.0 Letart Landfill..........................................................................................................37 5.1 Introduction.....................................................................................................37 5.2 Task A: Groundwater Well and Water-Use Surveying and C-8 Sampling..........................................................................................................37 5.3 Task B: Assessment of Existing Groundwater and Surface-water Monitoring Data..............................................................................................38 5.3.1 Monitoring of C-8 in Groundwater and Surface Water at Letart Landfill....................................................................................38 5.4 Task C: Plume Identification/Groundwater Assessment................................40 5.4.1 C-8 Monitoring in Groundwater and Surface Water at Letart Landfill..............................................................................................40 5.4.2 Surface-water Field Reconnaissance at the Letart Landfill...............40 5.4.3 Installation of New Wells at Letart Landfill................... 40 5.4.4 Letart Landfill Site Conceptual Model Refinement..........................41 5.4.5 Ohio River Water Sampling Near Letart Landfill............................ 41 5.5 Revised Site Conceptual Model......................................................................41 5.5.1 Current Environmental Setting..........................................................41 5.5.2 Current Human Health and Ecological Exposure Pathways.............46 5.6 Letart Landfill Summary.................................................................................48 6.0 Dry Run Landfill.......................................................... 50 6.1 Introduction.................................................................................................... 50 6.2 Task A: Groundwater Well and Water-Use Surveying and C-8 Sampling..........................................................................................................50 6.3 Task B: Assessment of Existing Groundwater and Surface-water Monitoring Data..............................................................................................51 6.3.1 Monitoring of C-8 in Groundwater and Surface Water at Dry Run Landfill.......................................................................................51 6.4 Task C: Plume Identification/Groundwater Assessment................................53 6.4.1 C-8 Monitoring in Groundwater and Surface Water at Dry Run Landfill.......................................................................................53 6.4.2 Surface-water Field Reconnaissance at the Dry Run Landfill........... 54 6.4.3 Installation of New Wells at Dry Run Landfill.................................54 6.4.4 Dry Run Site Conceptual Model Refinement....................................54 WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE ii 000012 C-8 Data Summary Report Table of Contents 6.5 Revised Site Conceptual Model......................................................................54 6.5.1 Current Environmental Setting..........................................................54 6.5.2 Current Human Health and Ecological Exposure Pathways............57 6.6 Dry Run Landfill Summary.............................................................................59 7.0 References............................................................................................................... 61 Table 3.0 Table 3.1 Table 3.2 Table 3.3 Table 3.4 Table 3.5 Table 3.6 Table 3.7 Table 3.8 Table 3.9 Table 3.10 Table 3.11 Table 3.12 Table 3.13 Table 3.14 TABLES Summary of Off-site Sampling Program (C-8 Sampling) - DuPont Washington Works Facility and Local Landfill Summary of C-8 Analytical Results in Groundwater and Surface Water (ug/1) - Washington Works Facility and Local Landfill (Off-Site Wells, Springs, and Cisterns - One-Mile Radius) Summary of Off-Site Sampling Program (C-8 Sampling) - Washington Works Facility and Local Landfill Two-Mile Radius Summary of C-8 Analytical Results in Groundwater and Surface Water (Off-Site Wells, Springs, and Cisterns) - Washington Works Facility and Local Landfill Two-Mile Radius) Summary of Off-Site Sampling Program (C-8 Sampling) - Ohio One-Mile Radius Residential Sampling Summary of C-8 Analytical Results in Groundwater and Surface Water Ohio One-Mile Radius Residential Sampling Summary of Off-Site Sampling Program (C-8 Sampling) - Ohio Two-Mile Radius Residential Sampling Summary of C-8 Analytical Results Zones A, B, and C - Ohio Two-Mile Radius Residential Sampling Monitoring Well Construction and Groundwater Elevation Data - DuPont Washington Works Facility Summary of Analytical Results: C-8 in Groundwater - DuPont Washington Works Facility Summary of Analytical Results: C-8 in Surface Water - DuPont Washington Works Facility Ohio River Water Sampling C-8 Results - DuPont Washington Works and Letart Landfill Outfall 005 C-8 Concentration (ug/1) - DuPont Washington Works Summary of C-8 in Groundwater - Public Water Supplies, West Virginia and Ohio - DuPont Washington Works Synoptic Groundwater Elevations, February 2002, and Well Screen Locations - DuPont Washington Works Facility WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 0000J.3 iii C-8 Data Summary Report Table of Contents Table 3.15 Table 4.0 Table 4.1 Table 4.2 Table 4.3 Table 5.0 Table 5.1 Table 5.2 Table 5.3 Table 5.4 Table 5.5 Table 6.0 Table 6.1 Table 6.2 Table 6.3 Table 6.4 Table 6.5 Summary of On-Site and Off-Site Exposure Pathways Evaluation DuPont Washington Works Facility Monitoring Well Construction and Groundwater Elevation Data - Local Landfill Summary of Analytical Results: C-8 in Groundwater - Local Landfill Summary of Analytical Results: C-8 in Surface Water - Local Landfill Summary of On-Site and Off-Site Exposure Pathways Evaluation - Local Landfill Summary of Off-Site Sampling Program (C-8 Sampling) - Letart Landfill Summary of C-8 Analytical Results in Groundwater (ug/1) - Letart Landfill (Off-Site Wells- One-Mile Radius) Monitoring Well Construction and Groundwater Elevation Data - Letart Landfill Summary of Analytical Results: C-8 in Groundwater - Letart Landfill Summary of Analytical Results: C-8 in Surface Water - Letart Landfill Summary of On-Site and Off-Site Exposure Pathways Evaluation - Letart Landfill Summary of Off-Site Sampling Program (C-8 Sampling) Dry Run Landfill Summary of C-8 Analytical Results in Groundwater and Surface Water (ug/1) - Dry Run Landfill (Off-Site Wells, Springs, and Cisterns - OneMile Radius) Monitoring Well Construction and Groundwater Elevation Data - Dry Run Landfill Summary of Analytical Results: C-8 in Groundwater - Dry Run Landfill Summary of Analytical Results: C-8 in Surface Water and Leachate - Dry Run Landfill Summary of On-Site and Off-Site Exposure Pathways Evaluation - Dry Run Landfill Figure 1.0 Figure 3.0 Figure 3.1 Figure 3.2 FIGURES DuPont Washington Works Properties Site Location Map - DuPont Washington Works Facility, Washington, WV One- and Two-Mile Radius Map - Local Landfill, Washington, WV One- and Two-Mile Radius - Summary of C-8 Results - Washington County, OH WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000014 iv C-8 Data Summary Report Table Of Contents Figure 3.3 Figure 3.4 Figure 3.5 Figure 3.6 Figure 3.7 Figure 3.8 Figure 3.9 Figure 3.10 Figure 3.11 Figure 3.12 Figure 3.13 Figure 3.14 Figure 3.15 Figure 3.16 Figure 3.17 Figure 3.18 Figure 4.0 Figure 4.1 Figure 4.2 Figure 4.3 Figure 4.4 Monitoring Well and Surface Water Sample Location Map - DuPont Washington Works Facility, Washington, WV C-8 in Groundwater - 4Q02- DuPont Washington Works Facility, Washington, WV Ohio River Water Sampling Locations - Upstream - DuPont Washington Works Facility, Washington, WV Ohio River Water Sampling Locations - Downstream - DuPont Washington Works Facility, Washington, WV C-8 Concentrations (ug/1) in the Ohio River and Public Water Supplies DuPont Washington Works Facility, Ohio - West Virginia Idealized Ohio River Valley Cross-Section and Block Diagram - DuPont Washington Works Facility, Washington, WV Generalized Geologic Cross-Section at River Mile 190 - DuPont Washington Works Facility, Washington, WV Cross-Section Location Map - DuPont Washington Works Main Plant, Washington, WV Cross-Section A-A' - DuPont Washington Works Main Plant, Washington, WV Cross-Section B-B' - DuPont Washington Works Main Plant, Washington, WV Cross-Section C-C' - DuPont Washington Works Main Plant, Washington, WV Cross-Section D-D' - DuPont Washington Works Main Plant, Washington, WV Cross-Section E-E' - DuPont Washington Works Main Plant, Washington, WV Cross-Section F-F' - DuPont Washington Works Main Plant, Washington, WV Cross-Section G-G' - DuPont Washington Works Main Plant, Washington, WV Revised - February 2002 Groundwater Elevation Map - DuPont Washington Works Main Plant, Washington, WV Site Location Map - Local Landfill, Washington, WV Local Landfill Monitoring Well and Surface Water Sample Location Map - Local Landfill, Washington, WV Cross-Section Location Map - Local Landfill, Washington, WV Geological Cross-Section A-A' - Local Landfill, Washington, WV Geological Cross-Section B-B' - Local Landfill, Washington, WV WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE OOOIS V C-8 Data Summary Report Table of Contents Figure 4.5 Figure 4.6 Figure 4.7 Figure 5.0 Figure 5.1 Figure 5.2 Figure 5.3 Figure 5.4 Figure 5.5 Figure 5.6 Figure 5.7 Figure 5.8 Figure 5.9 Figure 5.10 Figure 5.11 Figure 6.0 Figure 6.1 Figure 6.2 Figure 6.3 Figure 6.4 Figure 6.5 Figure 6.6 Figure 6.7 Figure 6.8 Figure 6.9 Geological Cross-Section C-C' - Local Landfill, Washington, WV A-Zone Groundwater Elevation Contour Map - 4Q02 - Local Landfill, Washington, WV C-Zone Groundwater Elevation Contour Map - 4Q02 - Local Landfill, Washington, WV Site Location Map - Letart Landfill, Letart, WV C-8 in Groundwater - Letart Landfill, Letart, WV Monitoring Well and Surface Water Location Sample Map - Letart Landfill, Letart, WV Rt. 33 Stream and Brinker's Run Surface Water Sampling Locations Letart Landfill, Letart, WV Ohio River Water Sampling Locations - Letart Landfill, Letart, WV Cross-Section Location Map - Letart Landfill, Letart, WV Cross-Section A-A' - Letart Landfill, Letart, WV Cross-Section B-B' - Letart Landfill, Letart, WV Geologic Cross-Section C-C' - Letart Landfill, Letart, WV Geologic Cross-Section D-D' - Letart Landfill, Letart, WV D/E-Zone Groundwater Contour Map - 4Q02 - Letart Landfill, Letart, WV F-Zone Groundwater Contour Map - 4Q02 - Letart Landfill, Letart, WV Site Location Map - Dry Run Landfill, Lubeck, WV C-8 in Groundwater - Dry Run Landfill, Lubeck, WV Monitoring Well and Surface Water Location Map - Dry Run Landfill, Wood County, WV Cross-Section Location Map- Dry Run Landfill, Wood County, WV Geological Cross-Section A-A' - Dry Run Landfill, Lubeck, WV Cross-Section B-B' - Dry Run Landfill, Lubeck, WV Geological Cross-Section A-C - Dry Run Landfill, Lubeck, WV Geological Cross-Section D-B'- Dry Run Landfill, Lubeck, WV A-Zone Groundwater Elevation Contour Map - 4Q02 - Dry Run Landfill, Wood County, WV B-Zone Groundwater Elevation Contour Map - 4Q02 - Dry Run Landfill, Wood County, WV WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 000016 VI C-8 Data Summary Report Table of Contents APPENDICES Appendix A Boring Logs and Well Construction Diagrams Washington Works Facility Appendix B Boring Logs and Well Construction Diagrams Local Landfill Appendix C Boring Logs and Well Construction Diagrams Letart Landfill Appendix D Boring Logs and Well Construction Diagrams Dry Run Landfill WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000017 vii C-8 Data Summary Report Executive Summary EXECUTIVE SUMMARY A multi-media consent order (Order No. GWR-2001-019; Consent Order) was entered into between the West Virginia Department of Environmental Protection (WVDEP), the West Virginia Department of Health and Human Resources - Bureau for Public Health (WVDHHR-BPH) and DuPont on November 15, 2001. The Consent Order identified a series of requirements and tasks to be performed by the parties (WVDEP, WVDHHRBPH, and DuPont) in order to determine whether there has been an impact on human health and the environment as a result of releases of ammonium perfluorooctanoate (C-8), CAS Number 3825-26-1, from DuPont operations at the Washington Works facility (facility, also referred to as the "main plant") and the associated landfills (Local, Letart, and Dry Run). The Consent Order established the C-8 Groundwater Investigation Steering Team (GIST) to oversee investigations and activities of the Consent Order including Task A: Groundwater Use and Well Survey/Groundwater Monitoring, Task B: Assessment of Existing Groundwater and Surface Water Monitoring Data, and Task C: Plume Identification/Groundwater Assessment at each site. The Consent Order also established the C-8 Assessment of Toxicity Team (CATT), which consisted of scientists from academia, government, non-profit organizations, and industry, to assess the toxicity and risk to human health and the environment associated with exposure to C-8 releases from DuPont activities. This C-8 data summary report documents all activities conducted to meet the requirements of the Consent Order. In addition, the revised site conceptual models are presented, which better represent the current environmental setting (geology, hydrology, hydrogeology, groundwater flow, and water quality) and current human health and ecological exposure pathways for the conditions at and near the sites. The table below shows the results of the exposure pathways evaluation. This evaluation assessed whether human and ecological receptors were exposed to C-8 impacted media (e.g., soils, surface water, groundwater) both on-site and off-site on the basis of data collected under the Consent Order. Pathways were classified as complete or incomplete. To be conservative, the highest C-8 concentration measured for each type of aqueous media was compared to the CATT-established human health protective screening criteria for water (C-8 SL) of 150 ug/1, regardless of media type. Note, however, that the CATTestablished Aquatic Life Advisory Concentration for C-8 (C-8 ALAC) of 1,360 ug/1 is a more appropriate benchmark for evaluation provided that waters are not ingested such as surface water, groundwater, process water, and leachate. In this table, highlighted boxes indicate media that exceed the C-8 SL. This table shows that for all on-site and off-site media evaluated for the facility and the three landfills, only leachate and surface water at Letart Landfill exceed the C-8 SL. If these media were compared to the established C-8 ALAC of 1,360 ug/1, only leachate at Letart exceeds the C-8 SL. Most importantly, this table shows that all drinking-water sources are substantially below C-8 SL. WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE viii 00004.8 C-8 Dala Summary Report Executive Summary On-Site Washington Works Facility C-8 Im pacted Media SWMUs/Landfilled Materials Soil Surface Water Groundwater Drinking water (from groundwater) Process water (from groundwater) Drinking Water (wells, springs and/or cisterns) - WV Non-drinking water (wells, springs and/or cisterns) - WV Unused water sources - WW Drinking Water (wells, springs and/or cisterns) - OH Non-drinking water (wells, springs and/or cisterns) - OH Unused water sources - OH Ohio River water PWS (WV and OH) O ff-site Local Landfill On-Site SWMUs/Landfilled Materials Soil Leachate Surface Water Groundwater Drinking Water (wells, springs +4+> and/or cisterns) - WV 1fi Non-drinking water (wells, springs t and/or cisterns) - WV Unused water sources - Local On-Site Letart Landfill SWMUs/Landfilled Materials Soil Leachate Surface Water Groundwater Drinking Water wells - Letart Non-drinking water wells- Letart Ohio River water Unused water sources - Letart O ff-site SWMUs/Landfilled Materials On-Site Soil *o3 Leachate (captured and treated) Surface Water Groundwater 3 Drinking Water (wells, springs OC > and/or cisterns) - Dry Run D Non-drinking water (wells, springs and/or cisterns) - Dry Run Unused water sources - Dry Run Exposure Pathw ay Assessment [Com plete (C) or Incom plete (1)] Human Receptors Ecological Receptors 1 1 1 1 C [1.9 (L) ug/l] C (51.2 ug/l) I I I I NA NA C (2.8 ug/l) C (2.8 ug/l) C (5.07 ug/l) I C (8.59 ug/l) C (23.6 ug/l) I G(1.09 ug/l) C (4.29 ug/l) I I C (120 ug/l) C (115 ug/l) I C (5.07 ug/l) I C (8.59 ug/l) C (23.6 ug/l) I C (1.09 ug/l) C (4.29 ug/l) I I C (120 ug/l) C (115 ug/l) I C (2.8 ug/l) C (5.07 ug/l) I I I C (2050 ug/l) C (371 ug/l) I C (0.139 ug/l) C [NQ (<0.05)] C (0.128 ug/l) I C (Unknown) C (Unknown) I C (87 ug/l) I C (2.8 ug/l) C (5.07 ug/l) I I I C (2050 ug/l) C (371 ug/l) 1 C (0.139 ug/l) C [NQ (<0.05)] C (0.128 ug/l) I C (Unknown) C (Unknown) I C (87 ug/l) I C (0.422 ug/l) C (0.54 ug/l) I C (0.422 ug/l) C (0.54 ug/l) I I Off-site (L) = biased low NA= not applicable Highlighted cells indicate exceedence of CATT-established C-8 SL (150 ug/l) WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000019 ix C-8 Data Summary Report Executive Summary For the Washington Worksfacility, the current revised site conceptual model combined with the current revised groundwater model, the current on-site and off-site C-8 concentrations measured, and the current exposure pathways evaluation show that: Solid Waste Management Units (SWMUs) on-site are believed to be the primary source of C-8 migration to groundwater. Air deposition of C-8 on the ground surface and migration to groundwater also may have occurred. No off-site migration of groundwater is occurring. No potential groundwater migration pathway exists beneath the Ohio River. Airemissions are believed to be the primary migration pathway of C-8 from the facility to adjacent areas in Ohio. Air emissions of C-8 from the facility also are believed to be the source of C-8 concentrations detected in West Virginia adjacent to the facility and Local Landfill. O Air emissions of C-8 and discharge of C-8 through outfalls are believed to be the migration pathways of C-8 from the facility to the Ohio River, and in turn, from the river to public water supplies (PWS) located downstream. There are no known complete exposure pathways for human or ecological receptors that exceed the CATT-established C-8 SL or the C-8 ALAC at the facility. For the Local Landfill, the current revised site conceptual model combined with the current on-site and off-site C-8 concentrations measured and the current exposure pathways evaluation show that: C-8 is believed to migrate via water transport from C-8 containing landfilled materials to groundwater at the Local Landfill. Groundwater flow from Local Landfill flows toward the facility to the northwest (away from off-site residential areas). C-8 detected in the one- and two-mile radius sampling areas near the facility and Local Landfill is likely to have been transported from the facility via air emissions. There are no known complete exposure pathways for human or ecological receptors that exceed the C-8 SL or the established C-8 ALAC at the Local Landfill. For the Letart Landfill, the current revised site conceptual model combined with the current on-site and off-site C-8 concentrations measured and the current exposure pathways evaluation show that: C-8 is believed to migrate via water transport from C-8 containing landfilled materials to groundwater at the Letart Landfill. Groundwater flow at Letart Landfill is toward the Ohio River and is away from off-site residential areas. WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 000020 X C-8 Data Summary Report Executive Summary The annual C-8 loading from groundwater to the Ohio River indicates a very low C-8 concentration in the river from the landfill, which is supported by the very low C-8 concentrations measured in the Ohio River. O Air emission of C-8 is not a viable migration pathway because there are no air emissions at Letart Landfill. O Contact with surface water (Cap Runoff location) and leachate at the toe of the Letart Landfill and in the wet-weather stream surface water that discharges to the Ohio River are complete exposure pathways for human or ecological receptors that exceed the C-8 SL. However, exposure is limited because of the remote location of the landfill, the very steep terrain, and the wet-weather nature of the stream. In addition, fencing limits access to the area. Further, the use of health and safety plans, standard operating procedures, and personal protective equipment also limit exposure. For Dry Run Landfill, the current revised site conceptual model combined with the current on-site and off-site C-8 concentrations measured and the current exposure pathways evaluation show that: C-8 is believed to migrate via water transport from C-8 containing landfilled materials to groundwater at the Dry Run Landfill. Groundwater flow at the site is toward the west. C-8 concentrations measured within the one-mile radius sampling area show that no off-site migration of C-8 impacted groundwater has occurred. Dry Run Landfill is located within eight miles of the facility. Transport of C-8 via air emissions from the facility potentially could be the source of the very low concentrations of C-8 detected within the one-mile radius sampling area. WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE xi 01)0021 C-8 Data Summary Report Introduction 1.0 INTRODUCTION Since the early 1950s, ammonium perfluorooctanoate (C-8) has been used by DuPont in its fluoropolymer-related manufacturing processes at the Washington Works facility (facility, also referred to as the "main plant"). Residues containing C-8 from these processes have been released to the air; discharged to the Ohio River; disposed of at the Washington Works facility and/or at the DuPont Local, Letart, and Dry Run landfills; and otherwise shipped off-site for destruction or disposal (see Figure 1.0). C-8 has been detected in varying concentrations in and around the Washington Works facility and the associated landfills (Local, Letart, and Dry Run), in private drinking wells and in public water supplies (PWS) located in West Virginia and in Ohio. A multi-media consent order (Order No. GWR-2001-019; Consent Order) was entered into between the West Virginia Department of Environmental Protection (WVDEP), the West Virginia Department of Health and Human Resources - Bureau for Public Health (WVDHHR-BPH) and DuPont on November 15, 2001. The Consent Order identified a series of requirements and tasks to be performed by the parties (WVDEP, WVDHHRBPH, and DuPont) in order to determine whether there has been an impact on human health and the environment as a result of releases of C-8, CAS Number 3825-26-1, from DuPont operations at the Washington Works facility and the associated landfills. The Consent Order established the C-8 Groundwater Investigation Steering Team (GIST) to oversee investigations and activities that were conducted to assess the presence and extent of C-8 in drinking water, groundwater, and surface water at and around the facility and the associated landfills, as described in Attachment A of the Consent Order. Pursuant to Attachment A of the Consent Order, three tasks were performed by DuPont and evaluated by the GIST, Tasks A, B, and C. Task A: Groundwater Use and Well Survey/Groundwater Monitoring involved evaluating C-8 in groundwater initially within a one-mile radius from the Washington Works facility and the three landfills by sampling water from wells, cisterns, and springs. Included with these sampling activities was the sampling of PWS located one mile upstream and ten miles downstream of the facility. The area of investigation was expanded based on results obtained. Twelve PWS located within a river reach extending 3.5 miles upstream and 53 miles downstream were sampled. Available results were included in the One-mile Radius Survey and C-8 Sampling Report and the Ohio River Public Water Supply Sampling (DuPont, 2002a). Task A activities are re-summarized in this report. Task B: Assessment of Existing Groundwater and Surface Water Monitoring Data included compiling historical C-8 data, monitoring all wells at the landfills, and developing a Groundwater Monitoring Plan (GMP) for the Washington Works facility and the Local, Letart, and Dry Run Landfills. The historical C-8 data compilation report was submitted to the GIST for evaluation (DuPont, 2002b). The second part of Task B, monitoring C-8 in surface water and groundwater at the landfills, began in December 2001. Sampling was performed monthly for four months and is now conducted quarterly. The Proposed GMP for the Washington Works facility (DuPont, 2002c) was submitted to the GIST for review and was approved following minor modifications (DuPont, 2002d). WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 1 000022 C-8 Data Summary Report Introduction Groundwater sampling at the Washington Works facility pursuant to the approved GMP began in late January 2002. Task B activities also are re-summarized in this report. Task C: Plume Identification/Groundwater Assessment at each site began following the completion of Tasks A and B. This activity included delineating the vertical and horizontal extent of C-8 impacted groundwater and specifically included an assessment of C-8 impacted groundwater at the Letart Landfill and its impact on the Ohio River and PWS along the river as required by the Consent Order. The C-8 Plume Identification Groundwater Assessment Work Plan was submitted to the GIST in May 2002 (DuPont, 2002e). For the Washington Works facility, Task C included groundwater modeling using GIST-approved groundwater modeling tools. Groundwater modeling was used to evaluate possible C-8 migration pathways in groundwater from the facility. A separate groundwater modeling report was issued to the GIST in January 2003 (DuPont, 2003a). This report documents Task C activities and re-summarizes briefly the groundwater modeling results. While conducting the activities identified in Tasks A, B, and C, which were designed to assess the presence and extent of C-8 in drinking water, surface water, and groundwater, an evaluation of transport mechanisms for C-8 migration also was conducted. This evaluation was conducted to gain a better understanding of how C-8 migrates in the environment and to better understand the results generated during the implementation of Tasks A, B, and C. Two main possible transport mechanisms were considered in evaluating results. These were air transport and water transport. Air transport was considered because DuPont had released, and continues to release, C-8 in air emissions from the facility. C-8 particles in air emission may have been deposited on surfaces of structures (roofs, etc.) and then have been dissolved and transported by precipitation into cisterns. C-8 in air emissions also may have been deposited on ground surfaces and dissolved and transported by precipitation to surface-water bodies or to groundwater. In addition, C-8 was detected at low concentrations in some of the water samples taken from cisterns. If the cistern was filled using a PWS that had been shown to contain C-8, then the source of the C-8 in the cistern may have been the water used to fill the cistern. Alternatively, the source of C-8 in the cistern may have been from air emissions. It also may have originated from both sources. Water transport, including transport via surface water and groundwater, was considered because C-8 bearing materials were disposed of on-site (i.e., facility and landfills) and C-8 had been detected in surface water and groundwater from various sources at and near the Washington Works facility and the three landfills. Sampling performed under Task A of the Consent Order resulted in detections of C-8 in the Little Hocking Water Association well field, which is the PWS located immediately across the Ohio River from the Washington Works facility. A formal groundwater modeling evaluation was performed to determine if imported groundwater from the facility migrated off-site toward Little Hocking. The Consent Order also established the C-8 Assessment of Toxicity Team (CATT). The CATT consisted of scientists from academia, government, non-profit organizations, and industry. The CATT was assembled to assess the toxicity and risk to human health and WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 2 000023 C-8 Data Summary Report Introduction the environment associated with exposure to C-8 releases from the DuPont activities. In a final report issued in August 2002, the CATT established the human health protective screening criteria for water (C-8 SL) of 150 ug/1 (WVDEP, 2002). The results presented in this report, which were obtained for Tasks A, B, and C, are compared conservatively to the CATT-established C-8 SL of 150 ug/1, regardless of water use. In addition, as reflected in the August 2002 report, the CATT also established a C-8 screening criteria of 240 mg/kg for soils (WVDEP, 2002). However, development of a method for analyzing C-8 in soils has not yet been completed; therefore, no soil samples have been analyzed. The CATT also established an Aquatic Life Advisory Concentration for C-8 (C-8 ALAC) of 1,360 ug/1 in October 2002 (Menzie-Cura & Associates, 2002). Surface-water results presented in this report are compared to these screening criteria and to the C-8 SL. 1.1 Document Organization Section 2 of this document provides information on C-8 reporting and data validation. The remainder of this report discusses specific activities conducted and results obtained at the facility and the Local, Letart and Dry Run Landfills. Section 3 presents the Washington Works facility data. Sections 4, 5, and 6, present data for the Local, Letart, and Dry Run Landfills, respectively. Within each section, a similar format is followed. A brief introduction is presented. The next three subsections then describe activities performed and results obtained for Tasks A, B, and C, respectively. The revised site conceptual model, which integrates the new results, is then discussed. A human health and ecological exposure assessment follows. Finally, observations for each site are summarized. Section 7 of the report provides a reference list, including Consent Order related documents previously submitted to the GIST. WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 3 000024 C-8 Data Summary Report C-8 Analyses and Analytical Reporting 2.0 C-8 ANALYSES AND ANALYTICAL REPORTING The Quality Assurance Project Plan (QAPP; DuPont, 2002f) discusses the procedures and protocols developed to ensure that project information, data, and decisions derived from or based on data acquired during the groundwater investigation at The facility and associated landfills are technically sound, usable, and properly documented. Specifically, Sections 5, 6, and 10 of the QAPP present sampling protocols, sample and document custody procedures, and internal quality control checks that were followed during the field sampling activities associated with the groundwater well and water-use survey. The QAPP also presents information on quality assurance, calibration procedures and frequency, analytical procedures, data reduction, verification, and reporting. Information on the analytical method and the precision criteria used for the C-8 reporting are summarized below. Exygen Research, Inc. (Exygen), located in State College, Pennsylvania, originally developed and tested a new analytical method that utilizes Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS). DuPont adopted this method (LC/MS/MS) for analyzing C-8 in water in November 2001. Currently, Exygen performs all C-8 water sample analyses for DuPont using the laboratory Standard Operating Procedure (SOP) it developed. Exygen reports C-8 results for the laboratory replicate of each field sample. These results are evaluated for precision by comparing the field sample result to the corresponding laboratory replicate result: O If both results are less than the practical quantitation limit (PQL), the replicate sample for that analyte is considered to have passed the precision criteria. If one or both results are between one and five times the PQL, the replicate is considered to have met the precision criteria if the two results differ by less than the PQL. If one result is less than the PQL and the other is not and if the two results differed by a value less than the PQL, the replicate is said to have met the acceptance criteria. Finally, if both results are at least five times the PQL, the replicate is considered to have met the criteria if the relative percent difference (RPD) between the two results is less than or equal to 20%. The RPD is the absolute value of the difference of two measurements divided by their average. When the precision criteria outlined above are met, Exygen reports the average of the field sample and the laboratory replicate results are reported. If criteria for precision are exceeded, Exygen reports the higher of the sample and laboratory replicate results. Finally, when one result (from the sample/laboratory replicate pair) is above the PQL and one below, the result that is above the PQL is reported. C-8 results are recorded in the Corporate Environmental Database (CED) and are reported as FC-143 for consistency with historical results. WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 4 000025 C-8 Data Summary Report C-8 Analyses and Analytical Reporting An aliquot of each field sample also is analyzed as a matrix spike (MS). Results of the MS analysis are used to assess accuracy. The MS recovery value must fall between 70 to 130%, unless the sample concentration is at least four times the amount spiked. The maximum amount used to spike field samples is 500 ug/1. The QAPP Addendum (QAPP Addendum, DuPont, 2002g) was generated during May 2002 in order to document a reduction in the number of laboratory QC samples (matrix spike and replicate) to a frequency of 5%, or one each per analytical batch (whichever is greater) for groundwater and surface-water samples collected within the facility and landfill boundaries. Specifically, analysis of well, outfall, and stream samples collected at the facility, Local Landfill, Letart Landfill, and Dry Run Landfill were subsequently performed with the reduced QC sample frequency. This reduction in QC sample frequency was made because a substantial database exists for these samples, including at least three rounds of sample analysis at Exygen. There was no reduction in QC sample frequency for samples collected outside the facility and landfill boundaries, such as off site wells, tap water samples, cisterns, PWS, and Ohio River water samples. All data packages generated by Exygen have been reviewed in-house for compliance with the laboratory SOP and QAPP Addendum, and for data usability, using the checklist provided in the QAPP. Results of the in-house review indicate that data reported by Exygen have been generated in compliance with the laboratory SOP and QAPP Addendum with few exceptions, as noted in the individual review summaries and discussed below. All data reported by Exygen have been judged usable for the purposes of the project. Exygen reported that seven of the Ohio two-mile radius samples (including two field blanks) from one data package, and two samples from Local Landfill, collected during November 2002 and reported in another data package, were analyzed beyond the sample hold time of 14 days (as per the SOP). These samples were analyzed within two times the specified hold time. The laboratory also has reported that non-project, field spiked samples at 100 and 1,000 ug/1, have exhibited stability for periods as long as one year (Exygen, 2002). The data packages were examined in-house, using the review protocol included in the QAPP, and the results were determined to be usable for project purposes. All data reported by Exygen have been judged usable for the purposes of the project. 2.1 Independent Quality Assurance Review A subset of the data packages generated by Exygen were submitted to Environmental Standards, Inc (ESI) in Valley Forge, Pennsylvania, for an independent (i.e., third-party) quality assurance review. Thirty-eight data packages, containing results for 326 samples, including field blanks and duplicates, were submitted for validation. The samples submitted for review represent samples collected from the West Virginia one- and twomile radius, Ohio one-and two-mile radius, Ohio River sampling, and PWS. The samples submitted for review represent 23.7% of the samples, collected between December 2001 and November 2002, from the West Virginia one- and two-mile radius, Ohio one-and two-mile radius, Ohio River sampling, PWS, and facility and landfill groundwater and surface-water sampling. Data packages/samples submitted for the independent quality assurance review were selected at random; however, off-site residential and PWS samples were preferentially selected because these samples were collected from drinking- WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000026 5 C-8 Data Summary Report C-8 Analyses and Analytical Reporting water sources. In addition, samples of particular interest to the GIST, such as samples yielding positive analytical results from the Ohio River sampling were submitted for review. The quality assurance review was performed by ESI with guidance from the Region III Modifications to National Functional Guidelines for Organic Data Review [United States Environmental Protection Agency (USEPA), 1994], Data were examined by ESI to determine the usability of the analytical results and compliance relative to the QAPP, QAPP Addendum, and the laboratory SOP. Results of the quality assurance review indicated that the quality of the data is acceptable and qualification of the data was not warranted, with the exception that positive results for two samples reviewed were qualified J, as estimated, due to precision criteria between the sample and lab replicate not being met. It should be noted that the laboratory, and DuPont, in this case and any similar cases for data not submitted for independent review, reported the higher of the two results. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000027 6 C-8 Data Summary Report Washington Works Facility 3.0 WASHINGTON WORKS FACILITY 3.1 Introduction The facility is located along the Ohio River in Washington, West Virginia, approximately seven miles southwest of Parkersburg, West Virginia (see Figure 3.0). Consent Order required tasks to be conducted at or immediately adjacent to the facility included the following: Task A: Groundwater Well and Water-Use Surveying and C-8 Sampling-- conduct a distance-phased groundwater well and water-use survey identifying and sampling all groundwater wells, springs, and cisterns within a one-mile (and possibly two- and three- mile) radial distance of the facility and the Local Landfill. Task B: Assessment of Existing Groundwater and Surface Water Monitoring Data--develop and implement a monitoring plan that evaluates the presence and extent of C-8 in drinking water, groundwater, and surface water in and around the facility and perform an assessment of C-8 impact to the Ohio River and to PWS within one mile upstream and 10 miles downstream (and possibly two and three miles upstream and 20 and 30 miles downstream) of the facility. Task C: Plume Identification/Groundwater Assessment--determine the vertical and horizontal extent of C-8 impacted groundwater exceeding 1 ug/1 or as directed by the GIST, using groundwater modeling tools approved by the GIST if modeling is done. In Sections 3.2 through 3.4, discussions of the specific activities conducted to meet the requirements of the Consent Order are presented along with the new data acquired while conducting these activities. In Section 3.5, the revised site conceptual model updates the current environmental setting (geology, hydrology, hydrogeology, groundwater flow, and water quality) and current human health and ecological exposure pathways for the conditions at and near the site. 3.2 Task A: Groundwater Well and Water-Use Surveying and C-8 Sampling 3.2.1 One-Mile Radius Sampling The Local Landfill is located immediately south of the facility. Because of the proximity of the Local Landfill to the facility, groundwater wells located within the combined onemile radius (of both sites) in West Virginia were sampled (see Figure 3.1). The groundwater well and water-use survey and sampling within the one-mile radius of the facility and the Local Landfill were completed on February 12, 2002. DuPont submitted the results of the one-mile radius survey to the GIST in April 2002 (DuPont, 2002a). WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 7 000028 C-8 Data Summary Report Washington Works Facility Table 3.0 summarizes the off-site survey and sampling program for the one-mile radius. A total of 269 homes were surveyed, and a total of 44 water sources were sampled. Six wells used for drinking water were sampled. No cisterns or springs sampled were used for drinking water. Table 3.1 provides details for each sample collected, including the C-8 concentration measured (ug/1). Figure 3.1 shows the locations of all samples collected, regardless of water use. Each colored circle represents a sampling location and the color and size of the circle indicate the magnitude of the C-8 concentration measured. For example, small black circles represent samples having C-8 concentrations ranging from to 1.0 to 10 ug/1, while large black circles represent samples having C-8 concentrations greater than 10.0 ug/1. Note that the number of C-8 detections above 10 ug/1 are limited. Table 3.1 shows that the C-8 concentrations in six drinking-water samples during the one-mile radius sampling ranged from 0.328 to 2.8 ug/1. Because the drinking-water samples had C-8 concentrations above the 1 ug/1 threshold level described by the Consent Order, the GIST ordered the expansion of the radius to two miles and resampling the drinking-water samples within the one-mile radius. The highest C-8 concentration in a non-drinking source was 5.07 ug/1. The highest C-8 concentration in unused water sources was 14.3 ug/1. C-8 concentrations measured in the six cisterns sampled ranged from 0.561 to 3.52 ug/1 (see Table 3.1). These results indicated that air transport of C-8 as a migration pathway was possible if cisterns were filled by precipitation. If water is added to the cistern from another source (groundwater, PWS, etc.) then water transport of C-8 is possible. Survey results from individual residents show that cisterns were filled predominantly by precipitation. 3.2.2 Two-Mile Radius Sampling The groundwater well and water-use survey and C-8 sampling within the two-mile radius of the facility and the Local Landfill were completed on June 3, 2002. DuPont submitted the results of the two-mile radius survey to the GIST in August 2002 (DuPont, 2002h). Table 3.2 summarizes the off-site survey and sampling program for the two-mile radius. Within the two-mile radius a total of 109 homes were surveyed, and 65 water sources were sampled. Seventeen wells and one spring used for drinking water were sampled. None of the eight cisterns sampled was used as a drinking-water source. Table 3.3 provides details for each sample collected, including the C-8 concentration measured (ug/1). Figure 3.1 includes the C-8 results for the two-mile radius. All samples are posted regardless of water use. Of the 18 drinking-water samples, only one (a spring sample) had a C-8 concentration greater than 1.0 ug/1. The C-8 concentration in the spring sample was 1.8 ug/1. All drinking-water samples from wells had C-8 concentrations less than 1.0 ug/1. The highest C-8 concentration measured in non drinking-water and unused water sources were 1.67 and 2.32 ug/1, respectively. C-8 concentration measured in the wells from the one-mile radius that were resampled ranged from 0.526 to 2.48 ug/1 (see Table 3.1). WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 8 000029 C-8 Data Summary Report Washington Works Facility Again C-8 concentrations measured in the eight cisterns indicated air transport as a possible C-8 migration pathway from the facility because the cisterns were predominantly filled via precipitation. The results for the two-mile radius showed a trend toward lower concentrations than were found in the one-mile radius sampling area. While the two-mile radius was being conducted, the CATT released the human health protective screening criteria for water (C-8 SL) of 150 ug/1 (WVDEP, 2002). In August 2002, the GIST determined that no further off-site surveying or resampling around the facility and the Local Landfill was needed. 3.2.3 Ohio One-Mile Sampling Off-site surveying and sampling also was conducted in Ohio. C-8 was initially measured in the Little Hocking Water Association well field (a PWS sampling point), located in Ohio directly across the Ohio River from the facility in December 2001 (see Section 3.3.3). DuPont and the Ohio Environmental Protection Agency (OEPA) agreed that the groundwater well and water-use survey would be expanded to a distance one mile from the facility boundary into Ohio. The groundwater well and water-use survey and C-8 sampling within the one-mile radius in Ohio were completed on June 7, 2002. DuPont submitted the results of the one-mile radius survey to the OEPA and the GIST in August, 2002 (DuPont, 2002i). Table 3.4 summarizes the one-mile radius survey and sampling in Ohio. The total number of homes surveyed was 150, and the total number of water sources sampled was 68. Of the 68 water sources sampled, 17 were from drinking-water wells, and one was from a drinking-water spring. No cisterns sampled were used for drinking water. Table 3.5 provides details on the samples collected, including the measured C-8 concentration. The C-8 concentration measured for the drinking-water wells ranged from non-detectable [<0.01 ug/1 (ND)] to 8.59. The C-8 concentration for a drinking-water spring was 1.29 ug/1. The highest C-8 concentration measured in non-drinking-water sources and unused sources was 23.6 and 16.9 ug/1, respectively. Figure 3.2 is a map showing the location of samples, regardless of water use, collected within the Ohio one-mile radius. This figure uses the same symbols as were used in Figure 3.1. Locations of samples having C-8 concentrations greater than 10.0 ug/1 appeared to be clustered to the northeast and northwest. C-8 concentrations measured in the five cisterns ranged from 0.748 to 7.33 ug/1. These results indicated that air transport of C-8 was a possible migration pathway from the facility, providing the cisterns were filled by precipitation. Even though the highest C-8 concentration measured for a drinking-water sample within the one-mile radius was an order of magnitude lower that the CATT established C-8 SL of 150 ug/1, nine non-drinking-water and unused water source samples had C-8 concentrations above 10.0 ug/1. Based on these results, OEPA requested an expansion of the survey area to a two-mile radius. 3.2.4 Ohio Two Mile Sampling The groundwater well and water-use survey and C-8 sampling within the two-mile radius of the facility were completed on September 30, 2002. DuPont submitted the results of WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 9 OO30 C-8 Data Summary Report Washington Works Facility the two-mile radius survey to the OEPA and the GIST in December, 2002 (DuPont, 2002j). For the Ohio two-mile radius, the sampling strategy was modified following discussions with the OEPA and the GIST. The two-mile radius survey area was divided into three areas, "A", "B", and "C"(see Figure 3.2). All homes within the entire area within the two-mile radius, areas "A", "B", and "C", were surveyed. In area "B" all identified wells, springs, and cisterns were sampled, regardless of use (drinking water, non-drinking water, or unused) because this portion of the two-mile radius was adjacent to an area within the one-mile radius where the highest C-8 concentrations were measured. In addition, all identified drinking water, non-drinking water, and unused wells, springs, and cisterns from residences located along Township Road 97 (located within area "C") were sampled. In area "A" and "C", wells, springs, and cisterns were sampled only if these sources were used for drinking-water; non-drinking-water and unused sources were not sampled. Areas "A" and "C" are adjacent to areas in the one-mile radius where lower C-8 concentrations were measured. Table 3.6 provides a summary of the Ohio two-mile survey results. In total, 733 homes were surveyed, and 62 water sources were sampled, including 49 wells used for drinking water. No cisterns or springs sampled were used as drinking-water sources. Figure 3.2 also shows the location of samples, regardless of water use, collected within the Ohio two-mile radius. Table 3.7 provides details of the samples collected, including the measured C-8 concentrations. The C-8 concentrations measured in drinking-water samples ranged from ND to 6.5 ug/1, with only 11 samples having C-8 concentration greater 1.0 ug/1. The highest C-8 concentration measured for the non-drinking-water samples ranged was 6.85 ug/1. The highest C-8 concentration measured in an unused source was 8.68 ug/1. The range of C-8 concentration in the three cistern samples was from 0.217 to 0.592 ug/1. Overall, the C-8 concentrations are lower in the two-mile radius samples than in the one-mile radius. While the groundwater well and water-use survey and C-8 sampling were being conducted in the one- and two-mile radius in Ohio, groundwater modeling also was being conducted. One of the objectives of the groundwater modeling effort was to determine the likelihood that off-site migration of C-8 impacted groundwater was occurring. The groundwater modeling showed that no potential groundwater migration pathway exists beneath the Ohio River (DuPont, 2003a). Therefore, air transport of C-8 is the most likely migration pathway for C-8 from the facility. 3.3 Task B: Assessment of Existing Groundwater and Surface-water Monitoring Data 3.3.1 Monitoring of C-8 in Groundwater and Surface Water Groundwater Monitoring The Consent Order required that a select number of facility monitoring wells were to be sampled following the development of a groundwater monitoring plan by DuPont (DuPont, 2002c) and its approval by the GIST (DuPont, 2002d). Frequency of sampling WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 10 000031 C-8 Data Summary Report Washington Works Facility was to be monthly for the first four months following the effective date of the Consent Order, then quarterly thereafter. Monthly sampling of groundwater began in January 2002. Quarterly sampling began in May 2002 (2Q02). The 4Q02 monitoring report was submitted to the GIST in December 2002 (DuPont, 2002k). Table 3.8 provides a list of the production and monitoring wells included in the groundwater monitoring program for the facility. Well construction data and groundwater elevation data also are provided in this table. The three new bedrock monitoring wells (AJ06-MW02, N04-MW03, and Y14-MW02) that were installed in 3Q02 as part of the C-8 plume delineation work plan were added to the monitoring program in 4Q02. Figure 3.3 shows the location the wells listed in Table 3.8. Table 3.9 presents all of the C-8 concentrations measured in these production and monitoring wells through October 2002, including C-8 data acquired prior to the issuing of the Consent Order. The most recent data are listed first for each well. Figure 3.4 shows the October 2002 C-8 concentrations in groundwater. Table 3.9 shows that, in general, monitoring and production wells located on the eastern half of the facility have shown a C-8 concentration range from 0.071 to 2.82 ug/1 (AE11-MW01, AM07-PW01, AO08-PW01, and AX13-PW01). Monitoring and production wells in the western half of the site generally have shown a C-8 concentration range of 0.117 to51.2 ug/1 (V05-PW01, L04-PW01, N13-MW01, Y14-MW01, K16-PW01, West Well Field 1, E13-MW01, and D08-MW01). Monitoring wells located adjacent to the Ohio River near the former Anaerobic Digestion Ponds have higher C-8 concentrations, ranging from less than 100 to 84,100 ug/1 (P08-MW01, P04-MW02, Q04MW02, and R04-MW02). However, evaluation of boring logs for these well shows that three of these wells are screened in a perched water-table located in the clays and silts that stratigraphically overly the sands and gravels of the primary site water-table aquifer (site aquifer). Q04-MW02 is the only well included in the groundwater monitoring program located in the former Anaerobic Digestion Ponds area that is screened in the site aquifer. Recent C-8 concentrations measured for this well have been highly variable, ranging from 32.2 to 7,720 ug/1. (Further discussion of the wells screened in the perched water-table are presented in Section 3.5.1.) Available data for the bedrock aquifer are very limited (only three wells) but ranges from non-quantifiable [<0.05 ug/1 (NQ)] in the central southern boundary (Y14-MW02) to 0.133 ug/1 along in the eastern portion (AJ06-MW02) of the site to 21.2 ug/1 in the area near the former Anaerobic Digestion Ponds (N04-MW03). The next groundwater sampling event for the facility is scheduled for the first quarter 2003. Surface-water Monitoring The Consent Order also identified six outfalls1at the facility that are regulated by West Virginia/National Pollutant Discharge Elimination System (WV/NPDES) Permit No. WV0001279 and where monthly sampling of C-8 was required. Figure 3.3 shows the locations of the six outfalls. Monthly sampling of outfalls began in December 2001. The 1In this report, all surface-water samples identified as outlets, inlets, or outfalls will be referred to collectively as outfalls. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 11 000032 C-8 Data Summary Report Washington Works Facility November 2002 Surface Water Monitoring Report was submitted to the GIST in January 2003 (DuPont, 2003b). Table 3.10 summarizes the C-8 concentrations measured in the outfalls, including C-8 data acquired prior to the issuing of the Consent Order. The most recent data are listed first for each outfall. The six outfalls sampled discharge process water and stormwater runoff to the Ohio River. The WVDEP permit required monthly reporting of effluent flow volumes and C-8 concentrations. Outfalls 002, 003, and 007 typically discharge effluent containing the lowest concentrations of C-8, ranging from NQ to 8.56, respectively. Outfalls 001 and 105 have discharged higher C-8 concentrations, ranging from 2.15 to 54.6 ug/1. Outfall 005 has shown the highest concentrations of C-8 and discharges the largest volume of effluent compared to the other outfalls at the facility. C-8 concentrations for Outfall 005 have ranged from 1.43 to 199 ug/1, with one anomalous high concentration of 915 ug/1. However, the C-8 concentration at Outfall 005 has generally decreased in 2001 and 2002 following the installation of a carbon filtration treatment system in the flouropolymers process. Outfall sampling for December 2002 has been completed, and the monitoring report will be issued to the GIST in February 2003. Outfall sampling for January 2003 has been completed, but the C-8 results have not yet been validated. The next monthly outfall sampling event is scheduled for February 2003. 3.3.2 Ohio River Water Quality Characterizing Ohio River water quality, with respect to C-8, was a Consent Order requirement. In addition, the evaluation river-water quality was identified as a data gap in the Compilation of Historical C-8 report (DuPont, 2002b) and was included as a recommended activity in the C-8 Plume Identification Work Plan (DuPont, 2002e). The Ohio River Water Sampling Proposal for the facility and the Letart Landfill (DuPont, 20021) was developed and submitted to the GIST in January 2002. Near the facility, Ohio River water was sampled to measure concentrations of C-8 in the Ohio River. The sampling investigation was designed to meet three main objectives: Characterize background C-8 concentrations in river-water upstream of the facility. Assess C-8 concentrations in river water along the facility reach. Evaluate C-8 concentrations in river water downstream. Table 3.11 presents a summary of the Ohio River water sampling program, including sampling near the Letart Landfill. The Letart Landfill samples and C-8 results are discussed in Section 5.4.5. Table 3.12 provides the C-8 results for Outfall 005. Figure 3.5 shows the location of upstream samples and samples along the facility reach. Figure 3.6 shows the concentration of downstream samples. C-8 concentrations for each sample are posted. In total, 46 river-water samples were collected, including two duplicate samples. Adjacent to the facility, river-water samples were collected at three locations along two transects across the river. Samples were collected at three depths (dip, mid-column, and WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 12 ooooaa C-8 Data Summary Report Washington Works Facility bottom) at each location. Field parameters were monitored during collection of each sample. During the same time period that river water was sampled, effluent from Outfall 005 was sampled to evaluate dispersion downstream of the outfall. Of the seven samples collected upstream of the facility, six were ND, and one was NQ. Of the 27 samples collected along the facility reach, all were ND except for two that were NQ. The range of C-8 concentration for the 12 downstream samples was 0.0949 to 1.09 ug/1. The two highest C-8 concentrations were measured in a dip and mid-column sample collected approximately three miles downstream from the facility. It is likely that the two highest C-8 concentrations measured in the Ohio River water are a direct result of increased C-8 concentrations discharged through Outfall 005. Table 3.12 shows that the C-8 concentrations measured at Outfall 005 are highly variable. C-8 data were not collected from Outfall 005 between July 1 and July 10; but, if C-8 concentration was higher on these days, it might explain why the higher concentrations were measured in the river during this same time frame. The revised groundwater model showed that no potential migration pathway for C-8 containing groundwater exists beneath the Ohio River. Therefore, air transport of C-8 to the Ohio River is a likely migration pathway, in addition to the direct discharge of C-8 containing surface water to the Ohio River through the permitted outfalls. 3.3.3 Public Water Supply Sampling PWS in West Virginia and Ohio at various points upstream of the facility were sampled pursuant to the Consent Order. Sampling of PWS within one-mile upstream and 10-miles downstream began in December 2001. Based on the C-8 concentrations measured, the distance upstream and downstream was expanded. Sixteen PWS located as far as three miles upstream and 53 miles downstream were ultimately included in the sampling events (see Figure 3.7). Based on the very low C-8 concentrations measured at the various PWS, the number of PWS required to be sampled and the frequency of sampling were reduced by the GIST in May 2002. Table 3.13 presents all the C-8 concentrations measured in the various PWS. For PWS sampled more than once, the sampling event results are listed in chronological order. Currently, only three PWS, Lubeck (West Virginia), Tuppers Plains (Ohio), and Little Hocking (Ohio) are sampled on a quarterly basis (DuPont, 2002m). C-8 concentrations measured at Lubeck ranged from 0.283 to 1.21 ug/1, while C-8 concentrations measured at Tuppers Plains ranged from ND to 0.726 ug/1 (see Table 3.13). Little Hocking had the highest C-8 concentrations of all the PWS sampled. C-8 concentrations in production wells have ranged from 0.42 to 8.58 ug/1. C-8 concentrations in drinking water dispersed to customers from these wells at the PWS have ranged from 1.69 to 4.29 ug/1. TW-4, a test well, had the highest measured C-8 concentration at 37.1 ug/1. The concentrations measured at TW-4 have been steadily decreasing; the most recent result for this well was 14.5 ug/1. Based on these results, OEPA requested that an investigation be conducted to evaluate the C-8 concentrations at TW-4 and vicinity, and DuPont agreed to conduct the investigation. DuPont has sampled groundwater and soil samples from borings and collected groundwater samples from all the test and production wells at Little Hocking. Groundwater results have been presented WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 13 000034 C-8 Data Summary Report Washington Works Facility to the OEPA. The method development for analyzing C-8 in soils is still in progress; therefore, none of the soil samples has been analyzed yet. As a result, no final conclusions have yet been drawn from this investigation. However, a report documenting the sampling investigation and the C-8 results for groundwater and soil will be submitted to the OEPA and the GIST when the analytical results have been finalized. The next PWS sampling event at Little Hocking, Lubeck and Tuppers Plains is scheduled for the first quarter 2003. 3.4 Task C: Plume Identification/Groundwater Assessment Based on the data gaps identified in the Compilation of Historical C-8 Data report (DuPont, 2002b), the C-8 Plume Identification/Groundwater Assessment Work Plan was developed and submitted to the GIST (DuPont, 2002e). Included in this work plan were specific activities recommended to fill the data gaps. In the following sections, each of the activities recommended in the C-8 plume delineation work plan is summarized briefly. Details of the activity status and the data acquired are then presented. 3.4.1 Installation of New Wells at the Washington Works Facility Three new bedrock monitoring wells were installed at the facility. These wells were installed to further delineate C-8 concentrations in groundwater, to evaluate groundwater flow direction and to determine the vertical groundwater gradients between the bedrock and the overlying sand and gravel. Figure 3.3 shows the location of monitoring and production wells, and the locations of the newly installed bedrock wells. Well construction diagrams for the new wells, AJ06MW02, NO4-MW03 and Y14-MW02, are provided in Appendix A. Geologic data obtained during the installation of these three wells confirmed the depth to bedrock underlying the facility where these wells are located. These new data also permitted refinement of existing cross-sections that were developed for the facility. These revised cross-sections are discussed in detail in Section 3.5.1.1. 3.4.2 Hydrogeologic Testing of New Wells at the Washington Works Facility Hydrogeologic testing of the three new bedrock wells was recommended to evaluate aquifer characteristics of the underlying bedrock aquifer in the C-8 Plume Delineation work plan. The bedrock monitoring wells were clustered with or located near existing wells screened in the primary site water-table aquifer. This allowed for the evaluation of the vertical gradients between the primary site water-table aquifer and the underlying bedrock aquifer. Only one round of water levels was measured for these wells (October 2002) and other wells nearby. The groundwater elevations indicate that at Q04-MW02 and surrounding sand and gravel aquifer wells, there is most likely an upward gradient between the groundwater in the bedrock and groundwater in the overlying sand and gravel near the former Anaerobic Digestion Ponds area. WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 14 000035 C-8 Data Summary Report Washington Works Facility At well cluster Y14-MW01 and Y14-MW02, located near the southern property boundary of the site, the groundwater gradient appears to be downward from the sand and gravel to the underlying bedrock. The water level measured in AJ06-MW02 in October 2002 is higher than in wells located nearby that were measured in February 2002, indicating a likely upward groundwater gradient from the bedrock to the overlying sands and gravel, in this area. 3.4.3 Washington Works Groundwater Model Refinement A groundwater model was developed for the facility as part of the RFI report for Washington Works (DuPont, 1,999). This model was revised during this investigation partially to address the comments generated by the United States Environmental Protection Agency and the United States Army Corp of Engineers (USACOE). The Consent Order also required refinement of the groundwater model for the facility to re evaluate the extent of groundwater captured by the pumping wells at the site and to determine the likelihood that off-site migration of C-8 impacted groundwater is occurring. To meet these requirements, refinement of the groundwater modeling work was completed with input, guidance, and critical review from the United States Geological Survey, the USACOE, the West Virginia Department of Health and Human Resources, and GIST members during the model development, calibration, and finalization process. The report of final findings for the revised groundwater model for the facility and the surrounding area was submitted to the GIST in January 2003 (DuPont, 2003a). The revised groundwater model supports DuPont's previous conclusions that no off-site migration of groundwater is known to be occurring and that no potential groundwater migration pathway exists beneath the Ohio River. 3.4.4 Surface-water Field Reconnaissance at the Washington Works Facility Conducting field reconnaissance to identify additional surface-water features located on site and sampling surface water from new locations identified during this effort was a C-8 plume delineation recommended activity. Field reconnaissance was performed and no new surface-water features were identified beyond those locations that are currently sampled. 3.4.5 C-8 Monitoring in Groundwater and Surface W ater at the Washington Works Facility Continuing to monitor C-8 in groundwater, in both the unconfined alluvial aquifer and underlying bedrock aquifer (utilizing the newly installed bedrock wells), and in surface water at existing locations identified in the Consent Order was an activity recommended in the C-8 plume delineation work plan. The results of continued monitoring of groundwater and surface water are presented in Section 3.3.1. WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 15 000036 C-8 Data Summary Report Washington Works Facility 3.4.6 Washington Works Facility Site Conceptual Model Refinement The final recommended activity for the facility is the integration of all the new data gathered during completion of Tasks A, B, and C into a revised site conceptual model (SCM). This activity was completed and the revised SCM is presented in the following section. 3.5 Revised Site Conceptual Model The revised SCM ideally represents the current environmental setting (geology, hydrology, hydrogeology, groundwater flow, and water quality) and current human health and ecological exposure pathways at and surrounding the site. The following sections present the revised SCM in detail. 3.5.1 Current Environmental Setting Geology The facility rests on Quaternary alluvial terrace deposits in the Ohio River Valley. Figure 3.8, modified from Simard (1989), is a model block diagram showing the complex set of terraces and floodplains that formed in the Ohio Valley because of the glacial advances and retreats of the pre-, early- and late-Wisconsinan and the resulting successive phases of alluvial fills and the incisions into the alluvial fill by the Ohio River. Simard (1989) identified five facies of the Ohio River Valley: sand and gravel (coarse-grained Ohio River alluvium or outwash); tributary sand and gravel; colluvium; silt and clay (fine grained Ohio River alluvium or overbank sediments); and sand and silt (eolian). A generalized north-south cross-section from the Little Hocking Water Association well field in Ohio, through the Ohio River and across the facility, is presented in Figure 3.9. This cross-section shows the Holocene silt and clay overbank deposits that overlie the Pleistocene sand and gravel outwash deposits and the finer reworked Pleistocene alluvium, thought to underlie the river. The alluvial terrace deposits are underlain by a flat, river-scoured bedrock surface of the Dunkard Series that rises steeply and forms the valley walls to the North of Little Hocking Water Association and to the south of the facility. Figure 3.0 shows the relatively flat topography of the alluvial terrace deposits and the steep topography of the valley walls to the north and south. The detailed geology underlying the facility is shown on seven geologic cross-sections. Six of these cross-sections were developed during the Verification Investigation (DuPont, 1992) and revised in early 2002 for the Compilation of Historical Data Report (DuPont, 2002b) based on additional findings from the RFI. Further refinement of these six crosssections, based on the installation of three bedrock wells, and the generation of a generalized cross-section near the former Anaerobic Digestion Ponds were completed as part of the C-8 Plume Delineation Work Plan activities. Some of the test wells and monitoring wells portrayed in the cross-sections were temporary and no longer exist. Table 3.14 provides well construction information and groundwater elevation measurements for wells currently in existence at the facility. Figure 3.3 shows the locations of monitoring wells that currently exist at the site. The locations of the geologic WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 16 000037 C-8 Data Summary Report Washington Works Facility cross-sections A-A' through F-F' are shown in Figure 3.10. The location of G-G' is shown on Figure 3.17. Two east-west cross-sections, A-A' and F-F', are shown in Figures 3.11 and 3.16. Four north-south cross-sections, B-B', C-C', D-D', and E-E' are shown in Figures 3.12, 3.13, 3.14 and 3.15, respectively. Cross-section G-G', Figure 3.17, shows an expanded view of the riverbank area near the former Anaerobic Digestion Ponds and the Riverbank Landfill. Note that wells R04-MW02 and P04-MW02 are screened in a perched groundwater zone within the Holocene overbank deposits. The main and oldest Quaternary alluvial terrace at the facility is topographically flat and lies approximately 50 feet above the Ohio River while the remains of younger terraces exist at lower elevations along the riverbank. The Holocene overbank deposits consist of silt, sandy silt, clay, silty clay, and clayey silt. The overbank deposits are approximately 35 feet thick near the riverbank and decrease in thickness away from the riverbank. Under the central portion of the facility, these overbank deposits range from approximately 5 to 15 feet thick. The overbank deposits are absent in the western portion of the site. The Quaternary alluvium (sand and gravel outwash deposits) ranges from 30 feet thick (near the river) up to 90 feet thick (under the central portion of the facility). The alluvium consists of coarsening downward unconsolidated poorly to well-sorted, brown and gray sand, silts, clay, and gravel. The Dunkard Series bedrock consists primarily of red and varicolored sandy shale; gray, green and brown sandstone; gray and light gray siltstone; and minor beds of coal, claystone, black carbonaceous shale, and limestone. Hydrology, Hydrogeology and Groundwater Flow Hydrology Surface water at the facility discharges through drains and storm sewers (outfalls) and drainage swales. Six outfalls (001, 002, 003, 005, 007, and 105) collect facility process water and stormwater runoff and discharge it to the Ohio River. These six outfalls are regulated by WV/NPDES Permit No. WV0001279. The locations of these outfalls are shown in Figure 3.3. Two drainage swales, one located in the facility's southwest comer, and the other located on the extreme eastern end of the facility, convey surface runoff during rainy weather to the Ohio River. During dry weather, the drainage swales are dry. The main groundwater seep area at the Riverbank Landfill was identified, RBLL1 and sampled during the VI (DuPont, 1992). This seep likely originates from precipitation that has infiltrated topsoil or fill and flows along the top of the underlying shallow clay and ultimately discharges along the riverbank (see Figure 3.3). An active French-drain groundwater collection system has been in operation at the Riverbank Landfill since 1991. The RFI verified that the collection system effectively captures water at the seep area (DuPont, 1999). Surface water from the seep is treated by a carbon filtration unit. This treated water discharges through Outfall 005 to the Ohio River. A second seep at the Riverbank Landfill (RBLL2) is located upriver from RBLL1 (see Figure 3.3). Seep water also is captured at this location by way of an active French-drain collection system. Seepwater is contained in an underground collection vessel that is WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 17 000038 C-8 Data Summary Report Washington Works Facility pumped out periodically, and the seep water is treated at the wastewater treatment facility on-site. Hydrogeology Regional groundwater supplies are obtained from the Dunkard Group bedrock and Ohio River alluvial terrace deposits. The saturated portion of the Ohio River alluvial terrace deposits comprise the principal regional aquifer used for water supply purposes. Production wells completed in this aquifer have been known to yield up to 500 gallons per minute (gpm) (Schultz, 1984). Based on these high yields, numerous industrial and commercial water supply companies obtain water from the alluvial aquifer. The yield from alluvial aquifer wells is related to the well's position with respect to the river, as well as formation grain size and thickness. The Holocene silts and clays underlying the facility contain perched groundwater zones. Along the riverbank, in the vicinity of the former Anaerobic Digestion Ponds, are seven monitoring wells that are completed in this perched groundwater zone (see Table 3.14). Groundwater elevations for these monitoring wells are typically 6 to 18 feet higher than elevations measured in monitoring wells completed in the underlying primary site watertable aquifer. During the February 2002 synoptic water level event, groundwater elevations in the perched water table ranged from 571.91 feet above mean sea level (MSL) to 583.46 feet MSL. Groundwater elevations in the underlying primary site watertable aquifer ranged from 552.15 to 566.62 feet MSL. Figure 3.17 shows a generalized cross-section for the area of the former Anaerobic Digestion Ponds showing the relationship between the Ohio River (normal pool elevation of 582.0 feet MSL), the perched water table, and the underlying primary site water-table aquifer. The primary site water-table aquifer occurs at a depth of about 60 to 70 feet bgs in the facility area. The saturated zone is approximately 30 to 40 feet thick, extending to the surface of the underlying Dunkard Group bedrock. The on-site production water wells completed in the site aquifer yield 200 to 450 gpm. The underlying Dunkard Group is not a major aquifer. The upper zone of the Dunkard Group (Washington Formation), which consists primarily of shale and siltstone, bounds the lower extent of the site aquifer. Natural recharge to the alluvial aquifer comes from various sources, including: Infiltration of precipitation falling directly on the alluvium Lateral movement of the river water through the alluvium via permeable sand and gravel zones Seepage from stream tributaries that discharge to the Ohio River The maximum amount of water available to the alluvium depends on the degree of hydraulic connection to the river. The degree of hydraulic connection is a function of the permeability and thickness of the riverbed, permeability and thickness of the alluvium, and hydraulic gradient between the groundwater and the river. Pumping of on-site active well fields near and parallel to the river (i.e., the Ranney Well, the DuPont-Lubeck Well Field, and the East Well Field shown in Figure 3.3) lowers the groundwater level in the alluvial aquifer to below river stage. This induces water from the river to flow into the WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 000009 18 C-8 Data Summary Report Washington Works Facility alluvium toward the wells, which replaces water pumped from storage in the aquifer, and helps sustain high-yield pumping wells. In a 1990 hydrogeologic assessment, production well specific capacity testing of the DuPont-Lubeck Well Field and the East Well Field was conducted. The results were used to calculate the transmissivity and the hydraulic conductivity of the primary site aquifer (DuPont, 1990). In the vicinity of the DuPont-Lubeck Well Field, transmissivity values ranged between 114,900 and 127,500 gallons per day per square foot (gpd/ft2). In the vicinity of the East Well Field, the transmissivity values ranged between 16,050 and 50,000 gpd/ft2. Hydraulic conductivity values were calculated from the transmissivity values for the East Well Field. For wells AX13-PW01 and AZ13-PW01, the hydraulic conductivity values ranged from 0.013 to 0.055 centimeters/second (cm/sec) and from 0.01 to 0.049 cm/sec, respectively. Using the hydraulic conductivity values from the 1990 study and the hydraulic gradient values determined from groundwater elevations measured in 1990 and assuming an effective porosity value for sand and gravel of 35 %, the groundwater flow velocity for several well pairs was calculated. The groundwater flow velocity was estimated at 5 feet/day (ft/d) between monitoring wells T13-MW01 and L18-MW01 in the southwest portion of the site. A groundwater flow velocity of 3 ft/d was estimated between monitoring wells P06-MW01 and K14-MW01 in the western central portion of the site. In the eastern portion of the site, a groundwater flow velocity of 2.5 ft/d was estimated for the site aquifer between monitoring wells AL10-MW01 and AO09-MW01. Groundwater Flow As part of the C-8 plume delineation work plan, a thorough evaluation of well survey data and well construction data was completed. This evaluation determined that incorrect measuring point elevations were used in calculating groundwater elevations that had been included in the monthly and quarterly monitoring reports. Since this discovery, all groundwater elevation calculations have been redone and corrected values were included in the 4Q02 C-8 monitoring report. In addition, the groundwater elevation map for February 2002, the most recent groundwater measuring event where almost all site wells were included, has been revised using the corrected groundwater elevations and is shown in Figure 3.18. Overall, the revised map did not alter groundwater flow directions on site. Figure 3.18 shows groundwater elevations and flow directions. It also shows flow rates on-site are strongly influenced by the Ohio River and by pumping of on-site production wells. Normal pool elevation for the Ohio River is 582.0 feet MSL, higher than the elevation of the primary site aquifer, indicating a gradient from the river to the primary site aquifer. The on-site production wells include the Ranney Well, a radial collector well which pumps 800 to 1,000 gpm; the seven wells in the East Well Field, which pump a combined average rate of 2,000 gpm; and the five DuPont-Lubeck wells, which pump about 700 gpm combined. A groundwater divide exists in the central part of the site with groundwater flowing to the east toward the East Well Field on the eastern side of the divide and to the west on the western side of the divide. Groundwater on the western side of the divide ultimately flows either back to the north toward the Ranney Well, or to the southwest toward the DuPont-Lubeck Well Field. From the northwestern comer of the WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 19 000040 C-8 Data Summary Report Washington Works Facility site, groundwater flows southeast toward the DuPont-Lubeck Well Field. The revised groundwater model supports the interpreted groundwater flow direction generated using groundwater elevations measured in the monitoring wells (DuPont, 2003a). As discussed in Section 3.4.2, the vertical gradient between groundwater in the sand and gravel and in the underlying bedrock has not been verified, although preliminary evaluation of available data indicates a predominantly upward gradient especially near the river that potentially may be reversed near the groundwater mound/divide located under the central and eastern portion of the facility (see Figure 3.18). The revised groundwater model supports an upward groundwater gradient between the bedrock and the overlying sand and gravel (DuPont, 2003a). Further data are needed to complete this evaluation and will be collected during future quarterly groundwater monitoring events. Water Quality Groundwater Quality The available C-8 concentration data for groundwater at the site was presented in Section 3.3.1. These data show that concentrations of C-8 in the groundwater are variable with the highest concentrations being measured in wells screened in the perched water-table located near the former Anaerobic Digestion Ponds. Historic C-8 concentrations in these wells range from less than 100 to 84,100 ug/1. Groundwater from wells screened in the primary site water-table aquifer has much lower C-8 concentrations than those screened in the perched water table. In addition, C-8 concentrations are variable depending on location of the monitoring well with respect to the locations of the pumping wells. Historic C-8 concentrations in wells located in the eastern half of the facility range from 0.071 to 2.82 ug/1. Historic C-8 concentration data for wells located in the western portion of the site are higher, ranging from 0.117 to 51.2 ug/1. Available data for the bedrock aquifer are very limited but range from 0.133 ug/1 in the eastern portion of the site, to NQ along the central southern boundary, to 21.2 ug/1 in the area near the former Anaerobic Digestion Ponds. The C-8 concentrations in groundwater from the monitoring wells screened in the perched water-table is not considered to be representative of the primary site water-table aquifer. Based on measured water elevations in the wells, the perched groundwater in the fine-grained silts and clays of the Holocene overbank deposits is most likely migrating downward into the underlying site aquifer. The rate of migration of groundwater from the perched water table to the underlying site aquifer is likely to be very slow because of the fine-grained sediments present in this area. Therefore, the contribution of the C-8 from the perched groundwater to the overall site groundwater quality is likely to be minimal. In addition, the groundwater at the site is currently captured by the facility production wells. Groundwater elevations at the site show that the site aquifer is recharged from the Ohio River and that groundwater at the site does not discharge from the site aquifer to the river. C-8 concentrations in groundwater pumped at the site and used for potable or industrial purposes are significantly below the C-8 SL of 150 ug/1 established by the CATT (WVDEP, 2002). For example, production well AM07-PW01 (historically known as WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 00041 20 C-8 Data Summary Report Washington Works Facility well 336) supplies potable water to the facility. C-8 concentrations in groundwater from AM07-PW01 have ranged from 0.071 (J) to 1.9 (L) ug/1. Surface-water Quality The available C-8 concentration data for surface water at the site was presented in Section 3.3.1. The six outfalls monitored at the facility all discharge process water and stormwater runoff to the Ohio River. Outfalls 003 and 007 discharge effluent with the lowest concentrations of C-8, ranging from NQ to 8.56 ug/1. Outfalls 002, 001, and 105 discharge higher concentrations ranging from 0.118 to 54.6 ug/1. Historically, Outfall 005 has shown the highest concentrations of C-8 and has discharged a larger volume of effluent compared to the other outfalls at the facility with concentrations ranging from 1.43 to 915 ug/1. Note that the 915 ug/1 measurement is unusually high compared to the other values measured at this outfall and likely was a sample collected when the system was temporarily off-line. Excluding this anomalous measurement, the C-8 concentration range is from 1.43 to 199 ug/1. The C-8 concentration at Outfall 005 has decreased in 2001 and 2002 following the installation of a carbon filtration treatment system in the flouropolymers process. Comparing the highest measured C-8 concentration in effluent from the outfalls, 915 ug/1, to the CATT-established the Aquatic Life Advisory Concentration for C-8 (C-8 ALAC) of 1,360 ug/1 shows that all values are lower than the criteria (Menzie-Cura & Associates, 2002). 3.5.2 Current Human Health and Ecological Exposure Pathways The main objective of the Consent Order was to determine whether there has been an impact on human health and the environment as a result of releases of C-8 to the environment from DuPont operations at the facility and the associated landfills (Local, Letart, and Dry Run). Therefore, human health and ecological exposure pathways both on-site (at the facility) and off-site (adjacent to the facility and the Local Landfill) were considered. The human health and ecological exposure pathway sections below describe the potential exposure routes for human and ecological receptors on- and off-site the facility/Local Landfill. Potential exposure routes were evaluated and classified as complete or incomplete. Table 3.15 summarizes the on-site and off-site human health and ecological exposure pathways evaluation for the facility. To be conservative, for each complete exposure pathways, the maximum C-8 concentration measured in the C-8 impacted aqueous media is compared to the C-8 SL, regardless of media type. On-Site Human Health and Ecological Exposure Pathways On-site human receptors include authorized facility workers and facility visitors. Ecological receptors include animals living within the facility boundaries. Direct exposure to C-8 bearing materials contained within the Solid Waste Management Units (SWMUs) is limited or non-existent because these materials have been removed and regraded or paved (Riverbank Landfill, Burning Ground, Waste Incinerators, and Digestion Ponds) or covered and vegetated. In addition, institutional controls (such as fencing) and excavation permits also limit exposure. Therefore, human and ecological receptor contact with these materials is considered to be an incomplete exposure pathway. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 21 000042 C-8 Data Summary Report Washington Works Facility A large portion of the facility is covered with asphalt and concrete. Surface-water contact with C-8 impacted soils or groundwater is not likely in these areas. Therefore, surface water contacting C-8 impacted soils is an incomplete exposure pathway. Much of the precipitation falling on-site is routed toward drains and storm sewers, which ultimately discharge into the Ohio River. Precipitation falling on the riverbank slope either infiltrates into the soil or runs off to the river. The seeps that occur in places along the riverbank are likely caused by infiltration of precipitation that accumulates above or in the low-permeability Holocene silt and clay overbank deposits that underlie topsoil and fill along the riverbank. Human receptor contact with impacted seep water is an incomplete exposure pathway due to the active French-drain groundwater collection system. Direct exposure to effluent discharging through the outfalls is an incomplete pathway because there are engineering and institutional controls (such as fencing) in place. Direct exposure to groundwater impacted by C-8 is also an incomplete pathway at the facility because groundwater is located at about 30 to 38 feet below ground surface (bgs) near the river bank and at 60 to 80 feet bgs under the central portion of the site. The only potential contact route for groundwater is via contact with water pumped from production wells. Water pumped from production wells is used for two purposes: supplying drinking water and providing industrial process water. Well AM07-PW01 is the production well that provides the majority of the drinking water to the facility. The other wells that provide drinking water at various times are AO08PW01 and AQ09-PW01. Because AM07-PW01 provides drinking water, it was included in the groundwater monitoring plan for the facility. C-8 concentrations in groundwater from AM07-PW01 have ranged from 0.071 (J) to 1.9 (L) ug/1. These concentrations are significantly lower than the CATT-established C-8 SL of 150 ug/1 (WVDEP, 2002). In addition, average concentrations of C-8 in drinking water at point of use (which is a mixture of water from the three wells) will be lower than the maximum concentrations detected in any single well. Human receptors contact with impacted drinking/tap water is a complete exposure pathway. C-8 was detected in production wells providing industrial process water (K16-PW01, V05-PW01, and L04-PW01). The maximum concentration of C-8 measured in these wells was 51.2 ug/1, detected in well V05-PW01. Water from these wells is not used for drinking, but rather for industrial processes including non-contact and contact cooling water, fire water, process water, conversion to demineralized water to generate steam, and/or consumption in the manufacturing processes. There is a potential for limited contact. However, this contact is expected to be minimal due to the low duration and frequency of contact and because health and safety procedures in place are followed when working with or around process water. Average concentrations of C-8 in process water at the point of use (which is again a mixture of water from several production wells) will be lower than maximum concentrations detected in any single well. An ecological evaluation conducted as part of the RCRA Facility Investigation focused on identifying whether significant ecological resources may be exposed to site-related constituents released from the SWMUs (DuPont, 1999). This evaluation concluded that surface soil at the Riverbank Landfill/Digestion Ponds was the only potential ecological exposure medium within the RFI study area. However, topsoil and a vegetation cover WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 22 000043 C-8 Data Summary Report Washington Works Facility prevent human and ecological receptor contact with surface soils (i.e., 0 to 1 feet). Therefore, the contact with surface soil at the Riverbank Landfill/Digestion Ponds is an incomplete exposure pathway. Surface-water contact with C-8 impacted soils or groundwater is not likely because the Waste Incinerators and Burning Ground SWMUs are covered with gravel, asphalt, or buildings and do not provide ecological habitat. Subsurface soil (greater than 2 feet) and groundwater are not exposure media of concern for ecological receptors, and groundwater does not discharge to surface water at the site. Therefore, contact with surface water or groundwater or subsurface soil is considered an incomplete ecological exposure pathway. Off-Site Human Health and Ecological Exposure Pathways Off-site human receptors include residents using the water sources sampled during the groundwater well and water-use survey. Ecological receptors include livestock using the water sources sampled during the groundwater well and water-use survey. West Virginia One- and Two-Mile Radius Groundwater and Surface Water Direct exposure to C-8 impacted surface water and groundwater is considered to be an incomplete pathway in situations where the water source is not used. The pathway is considered to be a complete pathway in situations where the water source is used but the water is not used for drinking-water purposes, although the exposure is considered to be minimal. The highest C-8 concentration in a non-drinking-water sample was 5.07 ug/1, well below the C-8 SL of 150 ug/1. The pathway is considered to be complete if the well is used for drinking-water purposes. The highest C-8 concentration measured in drinking water was 2.8 ug/1, significantly lower than the CATT-established C-8 SL of 150 ug/1 (WVDEP, 2002). Therefore, even though the pathway is complete, it also is considered to be limited due to the low C-8 concentrations measured. An evaluation of ecological exposure to groundwater and surface water shows that there is a complete pathway for exposure to livestock if these water sources are used for these purposes. Within the West Virginia one- and two-mile radius, the highest concentration of C-8 measured in water that was specified as a non-drinking-water source used for livestock is 5.07 ug/1, well below the CATT-established C-8 SL. Exposure of C-8 to ecological receptors is limited due to the low C-8 concentrations measured. Ohio One- and Two-Mile Radius Groundwater and Surface Water As stated in the previous section, the exposure pathway for groundwater varies from incomplete to complete depending upon water use. Within the Ohio one- and two-mile radius, the highest drinking-water C-8 concentration measured was 8.59 ug/1. This concentration is significantly lower than the C-8 SL of 150 ug/1 (WVDEP, 2002). While the pathway is considered to be complete, exposure also is considered to be limited. The pathway is complete for surface water because one spring used for drinking water within the one-mile radius was sampled. However, the C-8 concentration is low, 1.29 ug/1, compared to the CATT-established C-8 SL. An evaluation of ecological exposure to groundwater and surface water shows that there is a complete pathway for exposure to livestock if these water sources are used for these purposes. Within the Ohio one- and two-mile radius, no water sources identified as a WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 23 000044 C-8 Data Summary Report Washington Works Facility drinking water or non-drinking water were used for livestock. However, the highest C-8 concentration measured in a non-drinking-water sample, which may be used for livestock, was 23.6 ug/1. Ohio River Water Direct exposure to Ohio River water is a complete pathway, although the exposure is considered to be limited because river water is not directly used for drinking water. River water is ultimately the recharge source for PWS along the Ohio River. However, the highest C-8 concentration in the Ohio River water, 1.09 ug/1, is well below the C-8 SL. Public Water Supplies The highest C-8 concentration measured in connection with sampling related to PWS along the Ohio River was measured in a test well at Little Hocking Water Association, Ohio. However, this concentration does not represent the concentration of C-8 in drinking water supplied to the public. The highest C-8 concentration measured in the drinking water from the Little Hocking well field was 4.29 ug/1. Compared to the CATTestablished C-8 SL of 150 ug/1, this concentration is significantly below that level (WVDEP, 2002). The human health exposure pathway for groundwater from the Little Hocking well field is complete because the water is used for drinking and non-drinkingwater purposes. 3.6 Washington Works Facility Summary Many different activities were conducted at and around the facility in order to determine whether there has been an impact on human health and the environment as a result of releases of C-8 to the environment from DuPont operations at the facility. The C-8 concentration in groundwater and surface water from many sources (on-site, off-site, monitoring wells, production wells, private wells, springs, cisterns, river water, and PWS) was measured. More than 670 samples were analyzed. Based on all of the data evaluated for the Washington Works facility, the following observations were made: The current exposure pathways are incomplete for human and ecological receptors contact with the following C-8 impacted media: On-site SWMUs On-site soil On-site surface water On-site groundwater In addition, the current exposure pathways are incomplete for ecological receptors contact with the following C-8 impacted media: On-site drinking water On-site process water Current on-site human receptors contact with C-8 impacted drinking water is a complete pathway. However, this pathway is considered to be minimal because the highest C-8 concentration measured in drinking water at the site was 1.9 WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 24 000045 C-8 Data Summary Report Washington Works Facility (L) ug/1, significantly lower than the CATT-established C-8 SL of 150 ug/1 (WVDEP, 2002). Current on-site human receptors contact with C-8 impacted process water is also a complete pathway. However, this pathway is considered to be minimal because health and safety procedures are in place and followed when working with or around process water. The highest C-8 concentration measured in process water at the site was 51.2 ug/1, which is lower than the CATT-established C-8 SL of 150 ug/1. Current off-site exposure pathways for human and ecological receptors that are complete but minimal, due to the very low C-8 concentration measured, include residential and public drinking-water sources, residential non-drinking-water sources, and Ohio River water. For the drinking-water sources, the highest C-8 concentration measured was 8.59 ug/1, well below the C-8 SL of 150 ug/1. For the non-drinking-water sources, the highest C-8 concentration measured was 23.6 ug/1, which is significantly lower than the C-8 SL of 150 ug/1. For Ohio River water, the highest C-8 concentration was 1.09 ug/1, again significantly lower than the C-8 SL of 150 ug/1. The current revised groundwater model supports DuPont's previous conclusions that no off-site migration of groundwater is known to be occurring and that no potential groundwater migration pathway exists beneath the Ohio River. The current groundwater modeling observations combined with the current C-8 concentrations observed in groundwater, surface-water, and PWS in Ohio indicate that air transport of C-8 is the primary migration pathway for C-8 from the facility to adjacent areas. C-8 transported in air emissions and deposited on surfaces is likely to be mobilized by precipitation and migrate via water transport to surface water and/or groundwater. Air transport of C-8 in air emissions and water transport of C-8 directly discharging through facility outfalls into the river are believed to be the sources of C-8 in the Ohio River. The highest C-8 concentration measured in Ohio River water was 1.09 ug/1. This C-8 concentration is significantly lower than the CATT established C-8 ALAC of 1,360 ug/1 (Menzie-Cura & Associates, 2002). C-8 in the Ohio River is likely to be the source of C-8 in PWS located downstream of the facility. O SWMUs on-site are believed to be the primary source of C-8 migration to groundwater. Air disposition of C-8 on the ground surface combined with surface water transport to groundwater also may have occurred. The current groundwater modeling observations combined with the current C-8 concentrations observed in groundwater at the facility also support potential migration of C-8 from C-8 containing materials in the SWMUs directly into groundwater via water transport. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 25 000046 C-8 Data Summary Report Local Landfill 4.0 LOCAL LANDFILL 4.1 Introduction The Local Landfill is located immediately south of the Washington Works facility and consists of three separate closed cells. The three cells operated from 1964 to the mid1980s under WV/NPDES Permit No. WV0076538 (see Figure 4.0). When the cells were closed, the cells were covered with approximately 2 feet of low permeability soil and vegetative cover. Consent Order required tasks to be conducted at or immediately adjacent to the Local Landfill included the following: Task A: Groundwater Well and Water-Use Survey and C-8 Sampling--conduct a distance-phased groundwater well and water-use survey identifying and sampling all groundwater wells, springs, and cisterns within a one-mile (and possibly twoand three- mile) radial distance of the facility and the Local Landfill. Task B: Assessment of Existing Groundwater and Surface Water Monitoring Data--conducting monthly sampling for C-8 at Local Landfill at certain outfalls identified in WV/NPDES No. WV0076538 as Outfalls 101, 004 (Old), 004 (New), 005 (01d)/SS-l, and 005 (New). C-8 samples were to be taken from all the wells at the Local Landfill monthly for the first four months and quarterly thereafter. Task C: Plume Identification/Groundwater Assessment -determine the vertical and horizontal extent of C-8 impacted groundwater at Local Landfill exceeding 1 ug/1 or as directed by the GIST. In Sections 4.2 through 4.4, discussions are presented of the specific activities conducted to meet the requirements of the Consent Order along with the results of the sampling activities. In Section 4.5, the revised site conceptual model that better represents the current environmental setting (geology, hydrology, hydrogeology, groundwater flow, and water quality) and current human health and ecological exposure pathways for the conditions at and surrounding Local Landfill is presented. 4.2 Task A: Groundwater Well and Water-Use Surveying and C-8 Sampling The Washington Works facility is located immediately north of the Local Landfill. Because of the proximity of the facility to the Local Landfill, groundwater wells located within the combined one-mile radius (of both sites) in West Virginia were sampled. The results for the groundwater well and water-use surveying and sampling for the facility and the Local Landfill are presented in Section 3.2.1 and 3.2.2. Briefly summarized, expansion of the one-mile radius was required by the GIST because the C-8 concentrations in five drinking-water samples within the one-mile radius were above the 1 ug/1 threshold level. Within the two-mile radius, only one drinking-water sample had a C-8 concentration above 1.0 ug/1. The results for the two-mile radius showed a trend toward lower concentrations than in the one-mile radius. Based on these results, and the WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 26 000047 C-8 Data Summary Report Local Landfill establishment of the human health protective screening criteria for water (C-8 SL) of 150 ug/1 by the CATT, the GIST determined that no further off-site surveying around the facility and the Local Landfill was needed. 4.3 Task B: Assessment of Existing Groundwater and Surface-water Monitoring Data 4.3.1 Monitoring of C-8 in Groundwater and Surface Water Groundwater Monitoring The Consent Order required that all monitoring wells at Local Landfill were to be sampled for C-8. The frequency of sampling was to be monthly for the first four months following the effective date of the Consent Order, then quarterly thereafter. Monthly C-8 sampling of groundwater began in December 2001 and quarterly sampling began in May 2002 (2Q02). Table 4.0 provides a list of the monitoring wells included in the groundwater monitoring program for Local Landfill. Well construction and groundwater elevation data also are provided in Table 4.0. At the time monitoring started, only four monitoring wells existed at Local Landfill, LLMW-4, LLMW-6, LLMW-9, and LLMW-10. Another five wells were installed during 3Q02 as part of the C-8 plume delineation work plan, and these wells were included in the monitoring program starting in 4Q02. Figure 4.1 shows the location of the monitoring wells. Table 4.1 presents the C-8 concentrations measured in these monitoring wells, including C-8 data acquired prior to the issuance of the Consent Order. The most recent data are listed first for each well. At the present time, only general observations can be made from the five wells recently included in the monitoring program because of the limited data set. Additional groundwater monitoring data will be obtained during the 1Q03 event. However, for the four wells with multiple C-8 measurements, some observations can be made, and the results for the new wells can be compared to the historical data available. LLMW-4, LLMW-6, and LLMW-13B show the highest C-8 concentrations ranging from 1.32 to 79.6 ug/1. Shallow, overburden well LLMW-11A, only sampled once, had a C-8 concentration of 2.22 ug/1. The other five wells at the landfill have lower concentrations, ranging from ND to 1.12 ug/1. The next groundwater-sampling event for the Local Landfill is scheduled for the first quarter 2003. Surface-water Monitoring The Consent Order also identified three outfalls at Local Landfill (regulated by WV/NPDES Permit No. WV0076538) where monthly C-8 sampling was to be performed, Outfalls 101, 004 and 005. Monthly sampling of these three outfalls began in December 2001. In March 2002, two additional outfalls were added to the monitoring program due to a modification of the WV/NPDES permit. [The names of the two of the outfalls already included in the monitoring program were modified. Outfall 004 was renamed Outfall 004 (Old), not to be confused with Outfall 004 (New) and Outfall 005 was changed to Outfall 005 (01d)/SS-l, not to be confused with Outfall 005 (New).] WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000048 27 C-8 Data Summary Report Local Landfill Figure 4.1 shows the locations of the five outfalls in the monitoring program. The two 004 outfalls monitor a stream on the north side of the property and the two 005 outfalls monitor a stream located on the western side of the property. Both of these streams discharge stormwater runoff from the landfill. Surface water in the two.004 outfalls ultimately discharge to Pages Run, which crosses the facility and enters the Ohio River. Surface water in the two 005 outfalls crosses through the facility in stormwater pipes and ultimately discharges through Outfall 003 to the Ohio River. Outfall 101, located along the northeast perimeter of the landfill property, is located in a plastic sewer pipe that conveys seep water and leachate from a series of three holding ponds located on the east side of the landfill cells in addition to stormwater runoff. Water passing through Outfall 101 is conveyed via the sewer pipe to the Washington Works facility and ultimately discharges through Outfall 001 into the Ohio River. LM1 (Leachate) is a surface-water point that monitors leachate entering Pond 2, one of the holding ponds that then discharge through Outfall 001. LM1 (Leachate) and is monitored bi-annually for C-8. Table 4.2 provides the C-8 concentration data for the outfalls, including C-8 data acquired prior to the issuing of the Consent Order. The most recent data are listed first for each outfall. Outfall 101 is the only outfall that has consistently had flow since the beginning of the C-8 monitoring program. The other four outfalls have had no-flow conditions for the past three months, most likely due to the drought. The concentrations of C-8 in both 004 outfalls have been in the 10-15 ug/1 range, while the concentration in the both 005 outfalls have been higher, in the 20 to 50 ug/1 range. Outfall 101 has shown a wider range of C-8, from 12 to 115 ug/1. LM1 (Leachate) has had the highest C-8 concentration at Local Landfill (120 ug/1). Outfall sampling for December 2002 has been completed, and the monitoring report will be issued to the GIST in February 2003. Outfall sampling for January 2003 has been completed, but the C-8 results have not yet been validated. The next monthly outfall sampling event is scheduled for February 2003. 4.4 Task C: Plume Identification/Groundwater Assessment Based on the data gaps identified in the Compilation of Historical C-8 Data report (DuPont, 2002b), the C-8 Plume Identification/Groundwater Assessment Work Plan was developed and submitted to the GIST (DuPont, 2002e). This work plan included specific activities recommended to fill the data gaps. In the following sections, each of the activities recommended in the C-8 plume delineation work plan is summarized. Details of the activity status and the data acquired are then presented. 4.4.1 C-8 Monitoring in Groundwater and Surface W ater at Local Landfill Continuing to monitor C-8 in groundwater in the overburden and in the underlying bedrock aquifer (utilizing the newly installed monitoring wells), and in surface water at existing locations identified in the Consent Order, was an activity recommended in the C-8 plume delineation work plan (DuPont, 2002e). The results of continued monitoring of groundwater and surface water are presented in Section 4.3.1. Monitoring of C-8 in groundwater continues on a quarterly basis, while surface-water monitoring of C-8 is conducted on a monthly basis. WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 28 000049 C-8 Data Summary Report Local Landfill 4.4.2 Surface-water Field Reconnaissance at the Washington Works Facility Conducting field reconnaissance to identify additional surface-water features located at the Local Landfill and sampling surface water from new locations identified during this effort was a C-8 plume delineation recommended activity. Field reconnaissance was performed, and no new surface-water features were identified. 4.4.3 Installation of New Wells at Local Landfill The installation of four additional well clusters (overburden and bedrock) was proposed in the C-8 plume delineation work plan to further characterize the bedrock stratigraphy under the site, to further delineate C-8 concentrations in groundwater, and to evaluate groundwater flow direction. One well cluster, LLMW-11 A and B, and three bedrock wells, LLMW-12B, LLMW-13B, and LLMW-14B were installed during 3Q02. The overburden wells were not installed at three of the proposed well cluster locations because very little overburden was encountered and the overburden was dry. Figure 4.1 shows the locations of all monitoring wells at the Local Landfill including the locations of the newly installed monitoring wells. Well construction diagrams for the new wells, are provided in Appendix B. The geological logs for the five wells installed in 3Q02 confirm previous interpretations of subsurface conditions at the site. In general, some thickness of clay and weathered bedrock (shale, sandstone, and/or siltstone) is underlain by unweathered bedrock, which consists of alternating layers of shale and layers of sandstone and/or siltstone. Where the data were available, it confirmed that the lithologic units dip slightly toward the north. The new geological data were used to refine the geologic interpretation used for the revised SCM, which is presented in detail in Section 4.5.1. 4.4.4 Local Landfill Site Conceptual Model Refinement The final recommended activity for the Local Landfill was the integration of all the new data gathered during completion of Tasks A, B, and C into a revised SCM. This activity has been completed, and the revised SCM is presented in the following section. 4.5 Revised Site Conceptual Model The revised SCM better represents the current environmental setting (geology, hydrology, hydrogeology, groundwater flow, and water quality) and current human health and ecological exposure pathways for the conditions at and surrounding the Local Landfill. The following sections present the revised SCM in detail. 4.5.1 Current Environmental Setting Geology In 1989, eight monitoring wells were installed at the Local Landfill by Tetra Tech Richardson (LLMW-1 through LLMW-8). However, five of these monitor wells (LLMW-1, LLMW-2, LLMW-3, LLMW-5, and LLMW-7) were closed in 1996 because the wells were screened in the discontinuous shallow clays and underlying weathered WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 29 ooooso C-8 Data Summary Report Local Landfill bedrock. LLMW-8, a bedrock well, was closed in 1997. Two additional bedrock wells, LLMW-9 and LLMW-10 were installed in 1995 and 1997, respectively. LLMW-9 was installed as a background well. These two wells are screened within a sandstone layer that was selected as the significant underlying aquifer for SW/NPDES permit monitoring. Table 4.0 summarizes the well construction data for the existing monitoring wells. Five additional wells, LLMW-11A, LLMW-1 IB, LLMW-12B, LLMW-13B, and LLMW-14B were installed at Local Landfill in 3Q02 as part of the C-8 plume delineation work plan (DuPont, 2002k). The locations of three cross-sections developed for the Local Landfill are shown in Figure 4.2. Two cross-sections, A-A' and B-B', were presented in the Compilation of Historical Data Report (DuPont, 2002b) and have been modified to include data not previously available for LLMW-9 and LLMW-10. In addition, LLMW-12B, a newly installed well, was projected onto B-B'. A-A' runs west to east through the central portion of Local Landfill. B-B' runs north to south. Cross-sections A-A' and B-B' are shown in Figures 4.3 and 4.4, respectively. Cross-section C-C', shown in Figure 4.5, is a new cross-section that starts in the south and runs north, and then runs to the east, showing the geological data obtained from many of the newly installed monitoring wells. The Local Landfill is situated in a hilly area with high relief, up to 100 feet in some valleys, and lower relief of approximately 10 to 25 feet at the landfill cells. The slopes appear to be a combination of natural topography with terraced outcrops of massive sandstone and siltstone underlying varying amounts of soil cover and man-made landfill plateaus. A shallow, tight, clay overburden layer lies at the surface and ranges from 3 to 25 feet thick. The clay can contains some minor sandy and silty zones, and some pebbles and fragments of sandstone in some locations. The clays are of low plasticity and appear to be well compacted, often displaying a laminar structure (DuPont, 1990). Underlying the shallow clay layer is weathered shale, weathered sandstone, and/or weathered siltstone zone ranging from 10 to 35 feet thick (see Figure 4.3). Below this weathered bedrock, at depths ranging from 21 to 40 feet bgs, competent bedrock is present (see Figures 4.3, 4.4, and 4.5). The bedrock at the Local Landfill consists of inter-bedded red and varicolored sandy or calcareous shale, and gray, green, and brown sandstone and siltstone of the Permian age Dunkard Group. Cross-section B-B' (see Figure 4.4) shows that the sandstone layers dip gently toward the north. Most of the sandstone layers located in the upper portion of the stratigraphic section are lenticular and laterally discontinuous. However, four laterally continuous sandstone and/or siltstone layers are located in the lower stratigraphic section (see Figures 4.3, 4.4, and 4.5). These water-bearing units are referred to as A-Zone (the "underlying significant aquifer"), B-Zone, C-Zone, and D-Zone. These four zones are labeled on the cross-sections and are discussed in detail in the hydrogeology section that follows. Hydrology, Hydrogeology and Groundwater Flow Hydrology In general, infiltration of precipitation is limited due to the very low hydraulic conductivity (5 x 10'7cm/sec) of the surficial clays (where these clays exist) and the WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000051 30 C-8 Data Summary Report Local Landfill weathered bedrock (DuPont, 1992). In addition, infiltration of precipitation into the cells is limited by a surface cover that includes approximately 2 feet of low permeability soil and vegetation. Storm runoff flows into two streams, one located on the northern side of the property and one located on the southern side of the property. Surface water in these two streams is monitored. Outfalls 005(01d)/SS-l and 005(New) monitor surface water in the northside stream and Outfalls 004(01d) and 004(New) monitor surface water in the south-side stream. For the past few months, no-flow conditions have been observed at Outfalls 004 and 005, indicating that these streams have no base flow. Leachate from the southern cell and the eastern cell flows from the seeps in the steep valley walls to leachate collection ponds, Pond 1, 2, and 3 (see Figure 4.1). However, during the recent drought conditions of 2002, many seeps, which normally do flow, were not observed flowing. The lack of observed flow may be a result of the drought conditions. Leachate from these ponds is discharged into a pipeline. Monitoring of combined pond effluent conveyed in the pipeline is conducted at Outfall 101. Pond effluent is conveyed through Outfall 101 to the facility where it passes through stormwater Outfall 001 into the Ohio River. Hydrogeology Groundwater underlying the Local Landfill occurs in multiple stratigraphic units. A discontinuous upper layer consists of the clays and underlying weathered bedrock and has a very low hydraulic conductivity (DuPont, 1992). The lower layers consist of the continuous and discontinuous sandstone units having low permeability of 1 x 10`5cm/sec. The lower sandstone and/or siltstone layers are now identified as the A-Zone, B-Zone, C-Zone, and D-Zone based on re-evaluating the old geologic and hydrogeologic data and the new data obtained while installing and monitoring the new wells at Local Landfill. These four zones are indicated on the cross-sections wherever possible (see Figures 4.3, 4.4, and 4.5). The A-Zone through D-Zone are separated by laterally continuous shale layers. Well yields from the sandstone and siltstone layers are very low, ranging from <0.5 gpm to 1.5 gpm (DuPont, 1992). The highest laterally continuous sandstone layer is located at elevations between 710-740 feet above MSL (see Figures 4.3, 4.4, and 4.5) and is designated as the "underlying significant aquifer." This unit is currently monitored semiannually as required by the permit at monitoring wells LLMW-4, LLMW-6, LLMW-9, and LLMW-10. Based on the new geological data obtained, this unit also will be referred to as the A-Zone. The A-Zone outcrops in the western, northern, and eastern valley walls of the property. The next lower sandstone unit is designated as the B-Zone and is monitored via LLMW-12B. The B-Zone is located at elevations between approximately 665 and 694 feet above MSL. The B-Zone also should outcrop in the western, northern, and eastern valley walls of the property. The C-Zone is the next lower sandstone/siltstone unit and is monitored through wells LLMW-13B and LLMW-14B. The C-Zone is located at elevations between approximately 612 and 640 feet MSL. LLMW-11A, located to the south of one of the landfill cells, may be screened in a weathered portion of C-Zone. The screen is located at the correct elevation for C-Zone, and the lithology there is described as clay overlying silt WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 31 000052 C-8 Data Summary Report Local Landfill and sand. However, because it is located in a valley, the clay, silt and sand could be recent deposits instead of weathered bedrock. In addition, because there is stream nearby, there is likely to be a component of surface-water interaction involved at this location when the stream flows. The Outlets 004(01d) and 004(New), which monitor this stream, were dry during August, September, and October 2002. Based on the data available, LLMW-11A is considered to be part of the C-Zone monitoring wells. The lowest elevation on the north edge of the Local Landfill and the southern edge of the Washington Works facility is approximately 650 feet MLS. The highest elevation of C-Zone, approximately 640 feet MLS, is about 10 feet lower than the surface elevation indicating that this zone is not exposed at the surface but more likely, the edge of this zone contacts the alluvial material directly. The D-Zone is the lowest hydrogeologic unit encountered, 545 to 562 feet MSL, and is made up of siltstone and sandstone. LLMW-1 IB is the only well that was drilled deep enough to encounter the D-Zone; therefore, little information about the lateral continuity of this unit is available. This unit may have been encountered at LLMW-1; however, the distance between these two wells is too far to extrapolate the data. The D-Zone also does not outcrop on the surface and most likely contacts the Pleistocene alluvium directly in the subsurface. Groundwater Flow Groundwater elevations have been measured semiannually since 1994. Groundwater elevation contour maps for the significant underlying aquifer (A-Zone) have been prepared from these data as required by the WV/NPDES Permit No. WV0076538. Figure 4.6 presents the groundwater elevation map for 4Q02 for the A-Zone. A groundwater elevation map for 4Q02 for the C-Zone is presented in Figure 4.7. Note that data from LLMW-11A was used to make this map because the outfalls monitoring the stream next to these wells showed no-flow conditions. It was assumed that water elevations in this well were not highly influenced by surface water. Comparing Figures 4.6 and 4.7 shows that in general, groundwater in these two zones basically flows the same direction, toward the northwest. The direction of groundwater flow in the B-Zone and the D-Zone cannot be determined with the limited data available; however, groundwater flow in these two zones is likely to be similar to that observed in A-Zone and C-Zone. From a regional perspective, all bedrock groundwater is expected to generally flow north toward the Ohio River alluvial valley. Evaluation of limited groundwater elevation data for the closed wells (based on well installation information) indicates a downward vertical gradient between the upper discontinuous water bearing zone and the lower sandstone layers containing the underlying significant aquifer (A-Zone). Evaluation of groundwater data for the A-Zone and the C-Zone and of limited groundwater elevation data for the monitoring wells in the B-Zone and the D-Zone also indicates a downward vertical gradient between the zones. The sandstone/siltstones of the A-Zone (the underlying significant aquifer) and the B-Zone outcrop in the valley walls adjacent to the facility where groundwater discharge may flow downslope within the fractured rocks of the valley walls and ultimately enter the Quaternary alluvial terrace deposit underlying the Washington Works facility. Alternatively, groundwater also may discharge as seeps in the valley walls. Groundwater WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 32 000053 C-8 Data Summary Report Local Landfill from the A-Zone and B-Zone that discharges to seeps ultimately migrates to the facility through a number of pathways. It can discharge downward to leachate collection ponds and pipes (Outfall 101) and flow to the facility where it enters storm sewers and discharges to the Ohio River. Groundwater also can seep to small streams draining the property to the north [monitoring points Outfall 005(01d)/SS-l and 005(New)] and flow to the Quaternary alluvial terrace unconfined aquifer where pumping of on-site active well fields controls groundwater flow. Groundwater seeps in the southern valley wall can seep to the small stream that drains the southern part of the property and ultimately flows toward the north back on to the facility [Outfalls 004(01d) and 004(New)]. Groundwater from C-Zone and D-Zone, which are located in the bedrock at elevations lower than the alluvium surface, likely discharges to the alluvium in the subsurface. Groundwater flow in the alluvial aquifer, adjacent to the valley walls of the Local Landfill, is toward the pumping wells located near and parallel to the Ohio River. The pumping of these well fields lowers the groundwater level in the alluvium to below river stage, inducing surface water from the river to flow into the alluvium and toward the pumping wells. Water Quality Groundwater Quality Table 4.1 presents the data available for C-8 in Local Landfill monitoring wells. C-8 concentrations in the A-Zone, the underlying significant aquifer, are highest at LLMW-4 (maximum of 79.6 ug/1) and at LLMW-6 (maximum of 19.9 ug/1). These two wells are positioned adjacent to landfill cells and are the downgradient wells within the A-Zone. Monitoring well LLMW-10, located under a landfill cell and upgradient of LLMW-4, has shown a range in C-8 concentration of 0.15 to 1.12 ug/1. Monitoring well LLMW-9, an upgradient well located to the southwest of one of the landfill cells has shown C-8 concentrations ranging from non-detectable to 0.14 ug/1. These data indicate that C-8 from the landfill cells (and/or from air deposition) is migrating downward and reaching groundwater within the A-Zone. Water levels in the A-Zone show groundwater flowing from the southeast to the northwest within this zone. The C-8 concentration measured from the one well screened in the B-Zone (LLMW-12B) is very low, 0.0658 ug/1. Groundwater flow gradients indicate a downward gradient from the A-Zone to the B-Zone, which could be the migration pathway for C-8 to reach the B-Zone. However, groundwater flow with the B-Zone is toward the facility in the northwest and away from the one- and two-mile sampling area. C-8 concentrations for the one round of data for wells in the C-Zone, LLMW-11A, LLMW-13B, and LLMW-14B, are higher, 2.22, 6.61, and 0.488 ug/1, respectively, supporting a downward vertical gradient for groundwater from the A-Zone to the B-Zone to the C-Zone as indicated by groundwater elevations. Groundwater flow in the C-Zone is likely to be in the same direction as in the A-Zone and the B-Zone, to the northwest. The one C-8 value from the D-Zone is NQ (LLMW-1 IB). This may indicate that downward migration of C-8 to the D-Zone has not taken place. However, the location of this well is upgradient of the landfill cells WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 33 000054 C-8 Data Summary Report Local Landfill Groundwater flow in all zones monitored at the Local Landfill is toward the Washington Works facility (northwest). It is unlikely that C-8 impacted groundwater from any of the zones at Local Landfill would have migrated off-site into the one- and two-mile radius sampling area because of this northwest flow direction. Surface-water Quality C-8 concentrations in surface water are presented in Table 4.2. Outfall 101 monitors stormwater runoff and effluent from the leachate ponds and seeps that drain into the ponds. Outfall 101, which has never had no-flow conditions while it has been monitored, has had the highest C-8 concentration measured in surface water at Local Landfill, ranging from 12 to 115 ug/1. The C-8 concentration measured in a sample from Inlet 002 [LM1 (Leachate)], which collects seep water flowing to Pond 2, was 120 ug/1, in November 2002. Outfalls 004(Old), 004(New), and 005(Old)/SS-l and 005(New) are monitoring points . located along two streams on the southern and northern sides of the property, respectively. These outfalls collect stormwater runoff from the landfill cells. These four outfalls have all had no-flow conditions for the past several months. However, Outfall 005(Old)/SS-l historically has shown the highest C-8 concentrations of these four outfalls, ranging from 6.8 to 51.4 ug/1. 4.5.2 Current Human Health and Ecological Exposure Pathways The main objective of the Consent Order was to determine whether there has been an impact on human health and the environment as a result of releases of C-8 to the environment from DuPont operations at the Washington Works facility and the associated landfills (Local, Letart, and Dry Run). Therefore, human health and ecological exposure pathways both on-site (at the Local Landfill) and off-site (adjacent to the facility and the Local Landfill) must be considered. The human health and ecological exposure pathway sections below describe the potential exposure routes for human and ecological receptors on- and off-site. Potential exposure routes were evaluated and classified as complete or incomplete. On-Site Human Health and Ecological Exposure Pathways Current Environmental Setting This section describes the potential exposure routes for human and ecological receptors that are found at the Local Landfill. On-site human receptors include authorized facility workers and facility visitors. Ecological receptors include animals living within the landfill boundaries. Potential exposure routes were evaluated and classified as complete or incomplete and are summarized in Table 4.3. Table 4.3 summarizes the human health and ecological exposure pathway evaluation for the Local Landfill. To be conservative, for each complete exposure pathway, the maximum C-8 concentration measured in the C-8 impacted media is compared to the C-8 SL, regardless of media type. Access to the Local Landfill is restricted by electronic and locked gates at the road entrances. However, a posted nature trail has been established on the east side of the landfill property. The trail loops around the eastern part of the landfill starting and WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000055 34 C-8 Data Summary Report Local Landfill ending near the landfill's electrically operated gate. The nature trail is a marked trail and does not come near the cells. Access to the site from surrounding roads is possible but is discouraged due to the heavily wooded nature of the property and the hilly terrain. The three cells at the Local Landfill are covered with a low permeability soil and vegetative cover. This cover prevents human and ecological receptors' exposure to the landfilled materials. Permit WV0076538 requires that the landfill surface will be inspected quarterly for evidence of cracking or erosion (which could allow surface water to enter the solid waste deposit) and evidence of settling of solid waste (causing ponding of surface water). Per Condition G-16 of the permit, a stormwater erosion inspection is conducted annually. Therefore, human and ecological receptors' exposure to C-8 containing landfilled materials is an incomplete pathway. At the landfill, precipitation is expected to take one of two paths. It may infiltrate downward through the vegetated soil cover and into the cells, although, the low permeability of the soil cover reduces the amount of infiltration. If the precipitation does infiltrate the soil cover, it will possibly encounter the landfill materials and will continue migrating downwards. It may be prevented from further downward migration by the low permeability clays and weathered bedrock. However, if this water does migrate further downward, it should encounter the sandstones and shale layers. Groundwater flowing through the sandstone layers that outcrop in the valley walls located above the facility's southern edge would be exposed at the surface in seeps, if seeps exist. No seeps were identified in the valley walls during field reconnaissance. Seeps near the leachate collection ponds flow almost continuously although the amount of flow is variable. Contact with leachate from the landfill cells that has reached the ponds and surface water via these seeps is possible and therefore, is a complete exposure pathway for human and ecological receptors. However, contact would be very rare since only facility representatives enter this area on an infrequent basis. The highest C-8 concentration measured in leachate from Local Landfill 120 ug/1, which is lower than the CATTestablished C-8 SL of 150 ug/1 (WVDEP, 2002). Depths to groundwater at the Local Landfill ranges from around 20 feet to 130 feet bgs (see Figures 4.3, 4.4, and 4.5). In addition, groundwater has not been observed seeping in the valley walls indicating that ground water is not exposed at ground surface on valley walls, but most likely flows in the subsurface of the valley walls. Therefore, contact with C-8 impacted groundwater as an exposure pathway to human or ecological receptors is considered to be incomplete. Off-site Human Health and Ecological Exposure Pathways Off-site human receptors include residents using the water sources sampled during the groundwater well and water-use survey. Ecological receptors include livestock using the water sources sampled during the groundwater well and water-use survey. West Virginia One- and Two-Mile Radius Groundwater and Surface Water Results for the West Virginia one- and two-mile radius groundwater and surface water was presented in Sections 3.2.1 and 3.2.2. The exposure pathway is incomplete if the water source is not used. The exposure pathway for human and ecological receptors is complete if the water source is used for drinking water. The exposure pathway is WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 35 000056 C-8 Data Summary Report Local Landfill complete if the water source is used for non-drinking-water purposes, although, the exposure is considered to be minimal because the water is not ingested. The highest C-8 concentrations for non-drinking-water and drinking-water sources was 14.3ug/l and 2.8 ug/1, respectively, which are significantly below the CATT C-8 SL of 150 ug/1. The pathway is complete but exposure is limited due to the low C-8 concentrations. 4.6 Local Landfill Summary Many different activities have been conducted at and around the Local Landfill in order to determine whether there has been an impact on human health and the environment as a result of releases of C-8 to the environment from the landfill cells at the Local Landfill. The C-8 concentration in groundwater and surface water from many sources (on-site, off site, monitoring wells, production wells, private wells, springs, and cisterns) was measured. Based on all of the data evaluated for the Local Landfill, the following observations were made: The current exposure pathways are incomplete for human and ecological receptors contact with the following C-8 impacted media: On-site landfilled materials On-site soil On-site groundwater Human and ecological receptors contact with on-site leachate and C-8 impacted surface water are currently complete pathways. However, these pathways are considered to be limited because of health and safety practices followed when managing the leachate and because of institutional controls in place to limit access to the site. The highest C-8 concentrations measured in leachate and surface water at the site were 120 and 115 ug/1, respectively, which are lower than the CATT-established C-8 SL of 150 ug/1 and the Aquatic Life Advisory Concentration for C-8 (C-8 ALAC) of 1,360 ug/1 (WVDEP, 2002; Menzie-Cura & Associates, 2002). Current off-site exposure pathways for human and ecological receptors that are complete but limited, due to the very low C-8 concentrations measured, include residential drinking and non-drinking-water sources. For the drinking and nondrinking-water sources, the highest C-8 concentrations measured were 2.8 and 5.07 ug/1, respectively. These concentrations are well below the C-8 SL of 150 ug/1. Evaluation of the C-8 results measured at Local Landfill and the groundwater flow directions indicates C-8 migration via water transport from Local Landfill does not occur in any direction other than toward the Washington Works facility in the northwest but outside the boundary of the facility and the Local Landfill. C-8 detected at locations within the one- and two-mile radius is believed to have been transported from the Washington Works facility via air emissions. C-8 transported in air emissions and deposited on surfaces is likely to be mobilized by precipitation and migrate via water transport to surface water and/or groundwater. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000057 36 C-8 Data Summary Report Letart Landfill 5.0 LETART LANDFILL 5.1 Introduction The Letart Landfill is located about 46 river miles downstream of the Washington Works facility, north of the town of Letart in Mason County, West Virginia (see Figure 5.0). The landfill was operated and closed under WV/NPDES Permit No. WV0076066. The Letart Landfill was permanently closed by installing an engineered multi-layer geosynthetic and soil cap (DuPont, 2001). Included in the closure activities were the installation of a leachate collection system, erosion and drainage control measures, and chain-link fencing. The cap construction was completed in April 2001. The permit requires quarterly groundwater monitoring, surface-water monitoring, and engineered cap maintenance. Consent Order required tasks that were to be conducted at or immediately adjacent to the Letart Landfill included the following: Task A: Groundwater Well and Water-Use Surveying and C-8 Sampling--conduct a distance-phased groundwater well and water-use survey identifying and sampling all groundwater wells, springs, and cisterns within a one-mile (and possibly two- and three- mile) radial distance of the Letart Landfill. Task B: Assessment of Existing Groundwater and Surface Water Monitoring Data--conduct monthly sampling for C-8 at Letart Landfill at certain outfalls identified in WV/NPDES Permit No. WV0076066 as Outfalls 002 and 003. C-8 samples were taken from all the wells at the Letart Landfill monthly for the first four months and quarterly thereafter. Task C: Plume Identification/Groundwater Assessment--determine the vertical and horizontal extent of C-8 impacted groundwater exceeding 1 ug/1 or as directed by the GIST at Letart Landfill. This task included an assessment of the C-8 concentration in Ohio River Water in the vicinity of the Letart Landfill. In Sections 5.2 through 5.4, discussions are presented of the specific activities that were conducted to meet the requirements of the Consent Order, along with the results of the sampling events. In Section 5.5, the revised site conceptual model is presented that more accurately represents the current environmental setting (geology, hydrology, hydrogeology, groundwater flow and water quality) and current human health and ecological exposure pathways for the conditions at and surrounding the Letart Landfill. 5.2 Task A: Groundwater Well and Water-Use Surveying and C-8 Sampling The groundwater well and water-use survey and sampling activities conducted within the one-mile radius of the Letart Landfill were completed on February 24, 2002. DuPont submitted the results of the one-mile radius survey to the GIST in April, 2002 (DuPont, 2002a). WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000058 37 C-8 Data Summary Report Letali Landfill Table 5.0 summarizes the off-site surveying and sampling program for the one-mile radius. A total of 46 homes were surveyed, and a total of 30 wells were sampled. Eleven of the wells were used as drinking-water sources. Table 5.1 provides details for each sample collected including the C-8 concentration measured (ug/1). Eight other wells sampled were used for non-drinking water and the other 11 wells were unused. No cisterns or springs were sampled. Figure 5.1 shows the locations sampled, regardless of water use. Each colored circle represents a sampling location, and the color and size of the circle indicate the magnitude of the C-8 concentration measured. Small blue circles represent samples having C-8 concentrations less than 0.05 ug/1. Small green circles represent samples having C-8 concentrations ranging from to 0.05 to 1.0 ug/1. The C-8 concentrations measured in all Letart one-mile radius samples were ND or NQ, except for one sample collected from a well used for drinking water that had a C-8 concentration of 0.139 ug/1 and one sample collected from an unused well that had a concentration of 0.636 ug/1. The GIST required that the drinking-water well sample with a C-8 concentration of 0.139 ug/1 be re-sampled. However, the resident declined to have the well re-sampled. Based on the very low C-8 concentrations measured when compared to the human health protective screening criteria for water (C-8 SL) of 150 ug/1, the GIST determined that no further surveying and sampling was needed. 5.3 Task B: Assessment of Existing Groundwater and Surface-water Monitoring Data 5.3.1 Monitoring of C-8 in Groundwater and Surface Water at Letart Landfill Groundwater Monitoring The Consent Order required that all monitoring wells at Letart Landfill be sampled for C-8. Monthly C-8 sampling of groundwater began in December 2001 and quarterly sampling began in May 2002. Table 5.2 provides a list of the monitoring wells included in the groundwater monitoring program for Letart Landfill. Well construction data and groundwater elevation data also are provided in this table. At the time monitoring started, 13 monitoring wells existed at Letart Landfill. Another five wells were installed during 3Q02 as part of the C-8 plume delineation work. These wells were included in the monitoring program that began in 4Q02. Figure 5.2 shows the location of the monitoring wells. Table 5.3 presents the C-8 concentrations measured in these monitoring wells, including C-8 data generated prior to the issuing of the Consent Order. The most recent data are listed first for each well. The water-bearing units at the Letart Landfill are named from ground surface to depth as the A-Zone through the F-Zone, with the A-Zone being the shallowest and F-Zone being the deepest. Groundwater in the A-Zone, the uppermost water-bearing unit, is monitored through three wells, LMW-1, LMW-7, and LMW-8. These three wells are located along the northwestern edge of the landfill cell. C-8 concentrations in LLMW-1, LMW-7, and LMW-8 have ranged from 0.1 to 30,500 ug/1. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000059 38 C-8 Data Summary Report Letart Landfill Groundwater in the next lower water-bearing unit, the B-Zone, is not monitored because this zone is not laterally continuous at the site. Groundwater for the next lower water-bearing unit, the C-Zone, is monitored through LMW-3 and LMW-5A. C-8 concentrations in LMW-3 and LMW-5A ranged from NQ to 2,270 ug/1 and from 0.8 to 112 ug/1, respectively. Note that in the groundwater elevations measured for LMW-5A (see Table 5.2) have always been at depths lower than the bottom of the screen indicating that this well has been essentially dry throughout the period it has been monitored. Groundwater sampled from this well and analyzed for C-8 may not be representative of the C-8 concentrations in the C-Zone. Groundwater in the D/E-Zone, the next lower water-bearing unit, is monitored through LMW-3A, -4, -5B, -12, -13A, and -14A. C-8 concentrations in LMW-3A and 13A ranged from 60.3 to 510 ug/1. C-8 concentrations measured in LMW-4, -5B and -14A ranged from 172 to 3,060 ug/1. LMW-12 was dry during the 4Q02 sampling event. Groundwater in the F-Zone, the underlying significant aquifer, is monitored by LMW-2A, LMW-6, LMW-10, LMW-11, LMW-13B, and LMW-14B. C-8 concentrations measured in LMW-10, LMW-11, and LMW-13B have always been less than 1 ug/1. Concentrations of C-8 in LMW-6 ranged from 9.4 to 30 ug/1. C-8 concentrations in LMW-2A and -14B ranged from 50 to 990 ug/1. An additional sandstone and siltstone zone, located under the F-Zone is monitored by LMW-9. The C-8 concentrations measured in LMW-9 ranged from 0.2 to 0.907 ug/1. Table 5.2 shows that groundwater elevations in this well have consistently been below the bottom of the screen, indicating that this well has essentially been dry during the period that is has been monitored. In addition, LMW-9 typically runs dry during sampling and takes days to recharge. Therefore, C-8 concentrations measured in this well (0.2 to 0.907 ug/1) may not be representative of groundwater quality in this zone. The next groundwater sampling event at the Letart Landfill is scheduled for the first quarter 2003. Surface-water Monitoring The Consent Order identified two outfalls at Letart Landfill (regulated by WV/NPDES Permit No. WV0076066) that required monthly C-8 sampling to be performed, Outfalls 002 and 003. Outfall 002 collects leachate and stormwater runoff from the landfill. Outfall 002 then discharges to a small wet-weather stream at the toe of the landfill. Outfall 003 collects stormwater runoff. Monthly sampling of these two outfalls began in December 2001. DuPont also is sampling surface-water samples at selected other locations, including Stormwater Runoff, Rt. 33 Stream, Brinkers Run and Cap Runoff. Figures 5.2 and 5.3 show the locations of the six surface-water sampling points. Table 5.4 summarizes the C-8 concentrations measured in the outfalls, including C-8 data generated prior to the issuing of the Consent Order. The most recent data are listed first for each outfall. Outfall 002 collects landfill leachate. C-8 concentrations at this outfall have ranged from 4.52 to 3,240 ug/1. Using the 14 (see Table 5.4) C-8 results for samples collected after the landfill cap was installed in April 2001, the range is smaller, from 4.52 to 2,050 ug/1. The C-8 concentrations in this leachate have been highly variable since the landfill cap WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 39 000060 C-8 Data Summary Report Letart Landfill was installed. Cap Runoff C-8 concentrations ranged from 65.1 to 371 ug/1. The Stormwater Runoff sample had a concentration of 50.9 ug/1. The Rt. 33 Stream, Outfall 003, and Brinker's Run samples' C-8 concentrations ranged from 0.0612 to 3.92 ug/1. Outfall sampling for December 2002 has been completed and the monitoring report will be issued to the GIST in February 2003. Outfall sampling for January 2003 has been completed, but the C-8 results have not yet been validated. The next monthly outfall sampling event is scheduled for February 2003. 5.4 Task C: Plume Identification/Groundwater Assessment Based on the data gaps identified in the Compilation of Historical C-8 Data Report (DuPont, 2002b), the C-8 Plume Identification/Groundwater Assessment Work Plan was developed and submitted to the GIST (DuPont, 2002e). This work plan identified specific activities recommended to fill the data gaps. In the following sections, each of the activities recommended in the C-8 plume delineation work plan are summarized. Details of the activity status and the data acquired are then presented. In addition, Task C included an assessment of the C-8 concentrations in Ohio River Water in the vicinity of the Letart Landfill, and these results also are presented. 5.4.1 C-8 Monitoring in Groundwater and Surface W ater at Letart Landfill The delineation work plan recommended continuing to monitor C-8 in groundwater in the overburden and in the underlying bedrock aquifer (utilizing the newly installed monitoring wells), and in surface water at existing locations identified in the Consent Order. The results of continued monitoring of groundwater and surface water are presented in Section 5.3.1. Monitoring of C-8 in groundwater continues on a quarterly basis, while surface-water monitoring of C-8 is conducted on a monthly basis. 5.4.2 Surface-water Field Reconnaissance at the Letart Landfill Conducting field reconnaissance to identify additional surface-water features located at the Letart Landfill and sampling surface water from new locations identified during this effort was a C-8 plume delineation recommended activity. Field reconnaissance was performed, and no new surface-water features were identified. 5.4.3 Installation of New Wells at Letart Landfill The installation of three additional well clusters (overburden and bedrock) was proposed in the C-8 plume delineation work plan to characterize the bedrock under the Letart Landfill, to further delineate C-8 concentrations in groundwater and to evaluate groundwater flow direction. One bedrock well, LMW-12, and two well clusters, LMW-13A and LMW-13B and LMW-14A and LMW-14B, and were installed during 3Q02. At LMW-12, no overburden was encountered. Figure 5.2 shows the locations of all monitoring wells at the Letart Landfill including the locations of the newly installed monitoring wells. Well construction diagrams for the new wells, are provided in Appendix C. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 40 000061 C-8 Data Summary Report Letart Landfill Data from the geological logs for the five wells installed in 3Q02 support the previous interpretation of subsurface conditions at the site. Clay and weathered bedrock (shale, sandstone and/or siltstone) is underlain by bedrock, consisting of alternating layers of shale and sandstone, or siltstone or both. The A-Zone through the F-Zone and one additional water-bearing zone, under the F-Zone, were identified. The B-Zone, which exists in the northern areas, thins out toward the south while D/E-Zone exists in the south and thins out to the north. Overall, the new geologic data confirmed that the lithologic units dip slightly toward the south. The new geological data were used to refine the geologic interpretation used for the revised SCM, which is presented in detail in Section 5.5.1. 5.4.4 Letart Landfill Site Conceptual Model Refinement The final recommended activity for the Letart Landfill was the integration of all the new data gathered during completion of Tasks A, B, and C into a revised SCM. This activity was completed, and the revised SCM is presented in Section 5.5. 5.4.5 Ohio River W ater Sampling Near Letart Landfill Adjacent to the Letart Landfill, Ohio River water also was sampled to measure the C-8 concentrations. Two locations were sampled. These sampling locations are shown in Figure 5.4. One sampling location was positioned in the river near the point where the ravine originating at the landfill discharges surface water into the river. The other sampling point was located approximately 1,000 feet downstream of the first location. All samples were collected near the shoreline (approximately 100 feet east of the shoreline). Dip and mid-column samples were collected at both locations. In total, five river-water samples were collected, including one duplicate sample. The Ohio River water C-8 results for samples collected near the Letart Landfill are presented at the bottom of Table 3.11 and are shown in Figure 5.4. C-8 concentrations in these five samples ranged from 0.0971 to 0.128 ug/1. 5.5 Revised Site Conceptual Model The revised SCM better represents the current environmental setting (geology, hydrology, hydrogeology, groundwater flow, and water quality) and current human health and ecological exposure pathways for the conditions at and surrounding the Letart Landfill. The following sections present the revised SCM in detail. 5.5.1 Current Environmental Setting Geology At the time Consent Order was issued, 13 monitoring wells existed at Letart Landfill and monitored the water-bearing zones identified at the Letart Landfill, that are labeled as the A-Zone through F-Zone. Another five wells were installed during 3Q02 as part of the C-8 plume delineation work to better characterize the bedrock under the Letart Landfill, 1 WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 41 000062 C-8 Data Summary Report Letart Landfill to further delineate C-8 concentrations in groundwater, and to evaluate groundwater flow direction. The locations of four cross-sections developed for the Letart Landfill are shown in Figure 5.5. Two cross-sections, A-A' and B-B', were presented in the Compilation of Historical Data Report (DuPont, 2002b) and are shown in Figures 5.6 and 5.7, respectively. Figure 5.8 and 5.9, are new cross-sections, which starts in the north and runs south, showing the geological data obtained from the newly installed monitoring wells. The Letart Landfill is situated on a heavily dissected plateau consisting of several steep V-shaped valleys. Residual soil covers most landfill areas. In general, the soil at the site has been described as residual in nature, consisting primarily of heavy clays derived from the weathering of bedrock. At most landfill areas, the clay is less than 10 feet thick, with a maximum thickness of 20.5 feet. The underlying bedrock at the Letart Landfill consists of interbedded red and varicolored sandy or calcareous shale, and gray, green, and brown sandstone and/or siltstone of the Permian age Dunkard Group. Six stratigraphic water-bearing zones that were designated as the A-Zone through F-Zone, with the A-Zone being the shallowest zone and the F-Zone the deepest. These zones are identified on the cross-sections. These zones consist of massive, very fine to fine grained crystalline sandstone and/or siltstone with occasional shale lenses. The A-Zone through the F-Zone are separated by locally continuous shale units that are generally 10 feet or greater in thickness. The B-Zone through the D/E-Zone are laterally discontinuous. The B-Zone and the C-Zone are a single zone in the far north and separate into two distinct zones in the central area. The B-Zone thins out and is missing from logs from the southern area. D-Zone is an isolated unit in the northern area. This unit joins up with E-Zone in the central area. In the southern area, the D-Zone and the E-Zone are a single zone. The A-Zone and the F-Zone are laterally continuous. The A-Zone and the C-Zone outcrop in the valley walls, while the D/E-Zone outcrops along the Ohio River near the southern end of the landfill. The F-Zone likely outcrops in the riverbank of the Ohio River. The logs for LMW-9, LMW-5A, and LMW-5B were re-examined during construction of new cross-sections and are now believed to be screening other zones. LMW-9 is now interpreted to be screened in a sandstone zone lower than the F-Zone. Because there is only one well in this newly identified zone, it is not clear if this zone is laterally continuous. LMW-5B previously thought to be monitoring the F-Zone, is now believed to be screened in the D/E-Zone. Well LMW-5A, previously interpreted as monitoring the D/E-Zone, is now interpreted to be monitoring the C-Zone. Hydrology, Hydrogeology and Groundwater Flow Hydrology The Letart Landfill engineered cap system prevents surface water from contacting landfilled materials. Precipitation falling on the engineered cap system takes one of two paths. It may infiltrate downward through the vegetated soil and encounter the impermeable geomembrane and then flow laterally downslope on top of the geomembrane. Alternatively, precipitation may flow via overland flow on top of the vegetative layer downslope. In either situation, this surface water does not contact the WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 000063 42 C-8 Data Summary Report Letart Landfill landfilled materials and migrates downslope toward drainage ditches constructed in or adjacent to the cap system. Precipitation falling on the northwest side of the upper part of the cap flows downslope toward the southwest, away from the landfill, into a drainage ditch that flows to a sediment trap near LMW-6. Precipitation falling on the remaining portions of the cap flows downslope and toward the south in drainage ditches. Hydrogeology Hydraulic conductivity testing [i.e., slug tests (A-Zone) and borehole packer tests (C-Zone, D/E-Zone, and F-Zone)] of the bedrock zones indicates that these zones display low hydraulic conductivity (Tetra Tech Richardson, 1990). The A-Zone hydraulic conductivity is low, ranging from 10"4 cm/sec to less than 10'5cm/sec. (There are no wells monitoring the B-Zone; therefore, it was not tested.) The C-Zone and the F-Zone have very low hydraulic conductivities ranging from 10'6cm/sec to less than 1O'8cm/sec. The D/E-Zone hydraulic conductivities also are very low and range from 10'5cm/sec to 10'8cm/sec. The low hydraulic conductivities can be attributed to the very fine-grained nature of the water-bearing units. In addition, many sandstone units in the region typically display effective porosity as low as 1 percent. This low porosity results from pore space being filled in by authigenic minerals (e.g., kaolinite) sometime after original sediment deposition. The F-Zone has been designated the "underlying significant aquifer" as defined by the West Virginia Solid Waste Management Regulations because it is laterally continuous under the landfill and is thought to be hydraulically connected to the Ohio River south of the landfill. The F-Zone groundwater average linear velocities were calculated for flow from the north to the southwest and from the north to the southeast (DuPont, 2000). These values are relatively low, 0.01 and 0.003 ft/day, respectively. The low velocities calculated in the F-Zone indicate that groundwater flow beneath the landfill is very slow, attributable to the low hydraulic conductivity present in the F-Zone and all the overlying units as well. Low vertical hydraulic conductivities in the overlying shallow zones limit infiltration and recharge down to the F-Zone. The saturated thickness of F-Zone is higher in the upgradient wells (LMW-2A and LMW-11) and is lower in the downgradient wells (LMW-6, LMW-13B, LMW-14B, and LMW-10). In many instances, the monitoring wells at the landfill cannot be sampled until 48 hours (or longer) after purging, when a sufficient quantity of groundwater has recovered in the well screen interval. LMW-10 appears to essentially be dry (see Table 5.2). Groundwater Flow Groundwater elevation contour maps for the significant underlying aquifer (F-Zone) were prepared as required by the WV/NPDES Permit No. WV0076538. Table 5.2 provides groundwater elevation data for wells in the monitoring program. Figure 5.10 presents a groundwater elevation map for 4Q02 data from the D/E-Zone. Figure 5.11 presents groundwater elevation map for 4Q02 data from F-Zone. Note that Figure 5.11 has been revised compared to the groundwater elevation map for 4Q02 that was provided in the 4Q02 groundwater and surface-water monitoring report. Figure 5.11 now includes the WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000064 43 C-8 Data Summary Report Letart Landfill new wells that monitor the F-Zone. LMW-9, which is screened below the F-Zone, has been removed. Groundwater flow in both the D/E-Zone and the F-Zone is basically from the north toward the south. For Figure 5.10, the 4Q02 groundwater elevation contour map for the D/E-Zone, two wells that monitor this zone were not used. The D/E-Zone becomes quite complicated in the southern portion of the landfill area. In the very northern areas, the D/E-Zone does not exist. In the north-central portion of the landfill area, the D/E-Zone appears as a single lithological unit. In the south-central part, the D/E-Zone splits into a thinner upper unit and a thicker lower unit. At the toe of the landfill are three wells that monitor the D/E Zone, two are screened in the upper unit (LMW-3A and LMW-4) and one (LMW-5B) is screened in the lower unit. Although these wells are relatively close together, the groundwater elevations measured in these three wells differ significantly. Therefore, LMW-3A and LMW-4 were not used in constructing the groundwater elevation map because the elevations that were observed in these wells were not thought to be representative of overall groundwater flow within this zone. In general, ground water flow in this zone is from the north toward the south. Figure 5.11 presents the 4Q02 groundwater elevation map for the F-Zone. In this zone, groundwater also flows from the north. However, in the southern portion of the landfill, groundwater flow starts to be perpendicular the Ohio River and flows toward the southeast. For this groundwater elevation map, the water level measured for LMW-10 was not used. Table 5.2 shows that water levels in this well have consistently been within 1 foot of the bottom of the screen, and sampling this well has been difficult because the well frequently goes dry during purging and is very slow to recharge. In addition, water levels in this well are much lower than expected compared to adjacent wells. The location and limited number of monitoring wells within the A-Zone and the C-Zone prevents determination of groundwater flow directions within these zones. However, elevations measured in the monitoring wells indicate a downward vertical gradient within the site groundwater system. Rapid decreases in the observed volume of water discharging from the leachate collection system in 2001 indicate that groundwater flow under the landfill is being greatly reduced in response to the installation of the engineered cap system. Water Quality Groundwater Quality Table 5.3 presents all historical analysis available for C-8 from monitoring wells at the Letart Landfill. Data in this table are presented and discussed by zone. Figure 5.7 shows a cross-section through the southern end of the Letart Landfill. Prior to the filling of the valley, this cross-section shows that the A-Zone, the B-Zone, and the C-Zone most likely outcropped in the western valley wall, the C-Zone outcropped in the eastern valley wall, and the D/E-Zone likely outcropped in the valley floor. Further up the valley toward the north, it is likely that the A-Zone, the B-Zone, and the C-Zone outcrop on both the western and eastern sides of the valley. The landfill is an unlined WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 44 000065 C-8 Data Summary Report Letart Landfill landfill. This means that C-8 impacted water migrating through the landfilled material prior to the installation of the engineered cap may have been able to migrate directly into the C-Zone, then the B-Zone, then the A-Zone as the landfill was filled. The groundwater elevations also indicate that there is an overall downward gradient from the A-Zone to the F-Zone. This downward gradient also would help transport C-8 downward from one zone to the next lower zone. Groundwater flow within the zones also would move C-8 around within the individual zone. However, the installation of the engineered cap will minimize the amount of precipitation able to infiltrate into the landfilled material. The concentration of C-8 in the various wells in the different zones indicated that the C-8 impact is the greatest at differing locations within the zones, which is expected given that the C-8 concentration in the landfilled materials was most likely highly variable. In the A-Zone, LMW-1 shows the highest concentrations; and, in general, the C-8 concentrations appear to be increasing over time for all three wells. In the C-Zone, C-8 concentrations have been higher in LMW-3 than in LMW-5A. In the D/E-Zone, the highest C-8 concentrations are found in LMW-4 and LMW-5B, both located at the toe of the landfill. In the F-Zone, LMW-2A, which is located near the northern edge of the landfill, has the highest C-8 concentrations. In LMW-9, which monitors a zone lower than the F-Zone, C-8 concentrations have always been less than 1 ug/1. C-8 concentrations in groundwater from 28 residential wells located within a one-mile radius of the Letart Landfill have concentrations that are ND or NQ (DuPont, 2002a). Two groundwater samples had higher values, 0.139 and 0.636 ug/1. These data indicate that although the groundwater in the zones under and near the landfill cell has higher levels of C-8, the C-8 impacted groundwater has not migrated far. The 0.139 ug/1 sample is located amongst many other samples that had C-8 concentration of ND or NQ. The location of the 0.636 ug/1 sample is almost the same location as where the Rt. 33 Stream sample is collected. C-8 concentrations in the Rt. 33 Stream sample have ranged from 0.573 to 3.92 ug/1. It is possible that this well is in communication with C-8 impacted surface water at this location. The stream that is being sampled does receive surfacewater runoff from the landfill. The C-8 concentration measured within the One-mile radius are significantly lower that the CATT-established C-8 SL a of 150 ug/1. In the Compilation of Historical Data Report (DuPont, 2002b), the annual loading of C-8 to the Ohio River from C-8 impacted groundwater at Letart Landfill was calculated. The estimation was based on the assumption that impacted groundwater flows from the A-Zone downward to the F-Zone and ultimately migrates to the Ohio River. The C-8 historical mean for LMW-5B can be used along with the estimated groundwater flux to calculate the C-8 loading to the river. The estimated annual loading was 1x10-3 lb/yr. This calculated mass is reasonable given the low hydraulic conductivities and low average linear velocities observed in the F-zone. This annual loading should result in a very low C-8 concentration in the Ohio River. The annual loading estimation was recalculated using a new historical mean value for the C-8 concentration in LMW-5B now that more C-8 monitoring data are available. The new mean value is 1,149 ug/1, higher than the previous mean used. Therefore, the revised annual loading estimate is 0.017 lb/yr, also higher than previously estimated. The revised annual loading also should result in a very low concentration in the Ohio River. The WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 45 000066 C-8 Data Summary Report Letart Landfill measured C-8 concentrations in the Ohio River near the Letart Landfill are indeed low, with the maximum concentration measured being 0.128 ug/1. These concentrations are orders of magnitude lower than the C-8 SL of 150 ug/1 and the Aquatic Life Advisory Concentration for C-8 (C-8 ALAC) of 1,360 ug/1. Surface-water Quality Table 5.4 presents the C-8 results for surface-water locations monitored at the Letart Landfill. Sampling locations, Outfall 002, Cap Runoff, and Stormwater Runoff are associated with leachate from the landfill and have had the highest C-8 concentrations measured in surface water at the Letart Landfill. Cap Runoff and stormwater runoff have had C-8 concentrations ranging from 50.9 to 317 ug/1. Outfall 002, which discharges leachate and stormwater runoff, has had highly variable C-8 concentrations that have ranged from 4.52 to 2,050 ug/1 since the installation of the landfill cap. Outfall 003, which discharges stormwater runoff, has been dry or has had C-8 concentration lower than 0.4 ug/1. The Brinker Run sample, which was collected from a stormwater drainage ditch, had a very low C-8 concentation, 0.0612 ug/1. Stormwater runoff from the northern part of the landfill flows down the stormwater drainage ditch, off the property and into Blinker's Run. Brinker's Run discharges into a pond that is located off the north side of the landfill property. The Rt. 33 Stream sample is collected at the point where Blinker's Run enters the pond. The C-8 concentrations for the Rt. 33 Stream samples have ranged from 0.573 to 3.92 ug/1. The pond then discharges to the Ohio River. Other than Outfall 002 and Cap Runoff samples, all the surface-water samples for the Letart Landfill are less than the drinking water and the C-8 ALAC (WVDEP, 2002; MenzieCura & Associates, 2002). 5.5.2 Current Human Health and Ecological Exposure Pathways The main objective of the Consent Order was to determine whether there has been an impact on human health and the environment as a result of releases of C-8 to the environment from DuPont operations at the Washington Works facility and the associated landfills (Local, Letart, and Dry Run). Therefore, human health and ecological exposure pathways both on-site (at the Letart Landfill) and off-site (adjacent to the Letart Landfill) must be considered. The human health and ecological exposure pathway sections below describe the potential exposure routes for human and ecological receptors on- and off-site. Potential exposure routes were evaluated and classified as complete or incomplete. Table 5.5 summarizes the human health and ecological exposure pathway evaluation for the Letart Landfill. To be conservative, for each complete exposure pathway, the maximum C-8 concentration measured in the C-8 impacted media is compared to the C-8 SL, regardless of media type. On-Site Human Health and Ecological Exposure Pathways Current Environmental Setting This section describes the potential exposure routes for human and ecological receptors that are found at the Letart Landfill. On-site human receptors include authorized facility workers and facility contractors. Ecological receptors include animals living within the WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 46 000067 C-8 Data Summary Report Letart Landfill landfill boundaries. Potential exposure routes were evaluated and classified as complete or incomplete. The Letart Landfill closure was completed in April 2001 with the installation of an engineered cap system. The cap system drainage controls were designed to convey the runoff from the landfill cap to a designated discharge point and to eliminate the potential for runoff-related erosion of the cap. In addition, the landfill cap is required to be inspected at least quarterly (permit requirement C.12.A) for evidence of erosion as part of the landfill's Stormwater Pollution Prevention Plan. The engineered cap system prevents human and ecological contact with the landfilled materials and soils that may have been impacted by C-8. Contact with C-8 containing landfilled materials and soils is considered an incomplete exposure pathway to human and ecological receptors. The Letart Landfill engineered cap system also prevents surface water from contacting landfilled materials. Surface water flows toward drainage ditches constructed in the cap system and is discharged at the southern edge of the landfill. Because this surface water does not contact the landfilled materials, it is not impacted by C-8. However, leachate discharging from the leachate collection system is piped to Outfall 002 (leachate basin), where it mixes with stormwater runoff. Outfall 002 enters a small, wet-weather stream that flows approximately 400 feet before it discharges to the Ohio River. However, exposure is limited because of the remote location of the landfill, the very steep terrain, and the wet-weather nature of the stream. In addition, fencing limits access to the area. Further, the use of health and safety plans, standard operating procedures, and personal protective equipment also limit exposure. The highest C-8 concentration measured in leachate since the installation of the landfill cap was 2,050 ug/1. The highest C-8 concentration measured in the Ohio River adjacent to where this wet-weather stream enters the river was 0.128 ug/1. The D/E-Zone and the F-Zone exist at elevations lower than the leachate collection system. Groundwater flowing from these zones to the south discharges to the Ohio River. Contact with this water is limited to the areas where these zones may outcrop on the valley walls. However, in general, groundwater flows downslope within the shallow soil, colluvium, and fractured rocks of the valley walls and would only be exposed at the surface if seeps exist. Field reconnaissance did not identify any seeps in the valley walls; therefore, this exposure pathway for human and ecological receptors is incomplete. Off-site Human Health and Ecological Exposure Pathways Off-site human receptors include residents using the water sources sampled during the groundwater well and water-use survey. Ecological receptors include livestock using the water sources sampled during the groundwater well and water-use survey. West Virginia One-Mile Radius Groundwater and Surface Water Direct exposure to C-8 impacted surface water and groundwater is an incomplete pathway in situations where the water source is not used. The pathway is considered to be a complete pathway in situations where the water source is used, but not for drinkingwater purposes, although the exposure is considered to be minimal because the water is not ingested. The highest C-8 concentration in a non-drinking-water sample was NQ, well below the C-8 SL of 150 ug/1. The pathway is considered to be complete if the well WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 47 000068 C-8 Data Summary Report Letart Landfill is used for drinking-water purposes. The highest C-8 concentration measured in drinking water was 0.139 ug/1, significantly lower than the CATT-established C-8 SL of 150 ug/1 (WVDEP, 2002). Therefore, even though the pathway is complete, it also is limited due to the low C-8 concentrations measured. 5.6 Letart Landfill Summary Many different activities have been conducted at and around the Letart Landfill in order to determine whether there has been an impact on human health and the environment as a result of releases of C-8 to the environment from the landfill. The C-8 concentration in groundwater and surface water from many sources (on-site, off-site, monitoring wells, production wells, private wells, and Ohio River water) was measured. Based on all of the data evaluated for the Letart Landfill, the following observation were made: The current exposure pathways are incomplete for human and ecological receptors contact with the following C-8 impacted media: On-site landfilled materials On-site soil On-site groundwater Human and ecological receptors contact with C-8 impacted surface water and leachate (Cap Runoff and Outlet 002) discharging to the wet-weather stream at the toe of the landfill are currently complete exposure pathways. The highest C-8 concentrations measured at these locations are 371 and 2,050 ug/1, respectively. However, exposure is limited because of the remote location of the landfill, the very steep terrain, and the wet-weather nature of the stream. In addition, fencing limits access to the area. Further, the use of health and safety plans, standard operating procedures, and personal protective equipment also limit exposure. Current off-site exposure pathways for human and ecological receptors that are complete but limited, due to the very low C-8 concentration measured, include residential drinking and non-drinking-water sources and river water. For the drinking and non-drinking-water sources, the highest C-8 concentrations measured were 0.139 and NQ, respectively, which are well below the C-8 SL of 150 ug/1 (WVDEP, 2002). The highest C-8 concentration measured in Ohio River water is 0.128 ug/1, well below the C-8 SL of 150 ug/1 and the 1,360 ug/1 C-8 ALAC developed by the CATT (Menzie-Cura & Associates, 2002). O Groundwater flow in the site significant aquifer under the landfill is toward the southwest and the Ohio River. C-8 impacted groundwater from the water-bearing zones at Letart Landfill ultimately flows into the Ohio River. O Evaluation of the groundwater flow directions at the landfill and of the Letart onemile radius C-8 results shows that C-8 impacted groundwater is not migrating toward off-site residences. The revised C-8 annual loading estimate from groundwater indicates a very low C-8 concentration in the Ohio River from the Letart Landfill. This low estimated concentration is supported by C-8 concentrations measured in the Ohio River WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 000069 48 C-8 Data Summary Report Letart Landfill (0.128 ug/1) that are well below the C-8 SL and the C-8 ALAC that were determined by the CATT (WVDEP, 2002; Menzie-Cura & Associates, 2002). The transport pathway of C-8 at the Letart Landfill is believed to be via water transport from C-8 containing landfill materials. Air emission of C-8 as a migration pathway is not possible because there are no air emissions at the Letart Landfill. In addition, the Letart Landfill is too far away from the Washington Works facility to be impacted by C-8 containing air emissions emanating from the facility. WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 000070 49 C-8 Data Summary Report Dry Run Landfill 6.0 DRY RUN LANDFILL 6.1 Introduction The Dry Run Landfill is located west of the town of Lubeck, in Wood County, West Virginia, about eight miles southwest of the Washington Works facility and the Local Landfill (see Figure 6.0). The landfill covers approximately 17 acres of a 535-acre parcel of land owned by DuPont. The landfill was constructed within the drainage basin of Dry Run, a tributary of the North Fork of Lee Creek, which is a tributary of the Ohio River. The landfill began operation in 1986 and the central portion is still active and operates under WV/NPDES Permit No. WV 0076244. The upper portion of the landfill is closed and is covered with a soil and vegetative cover. The lower portion of the landfill also is closed and is covered by a engineered landfill cap. Consent Order required tasks to be conducted at or immediately adjacent to the Dry Run Landfill included the following: Task A: Groundwater Well and Water-Use Surveying and C-8 Sampling-- conduct a distance-phased groundwater well and water-use survey identifying and sampling all groundwater wells, springs, and cisterns within a one-mile (and possibly two- and three- mile) radial distance of the facility and the Dry Run Landfill. Task B: Assessment of Existing Groundwater and Surface Water Monitoring Data--conduct monthly sampling for C-8 will be performed at Dry Run Landfill at outfalls identified in WV/NPDES Permit No. WV0076244 as Outfalls 001, 003, and 004. C-8 samples were to be taken from all the wells at the Dry Run Landfill monthly for the first four months and quarterly thereafter. Task C: Plume Identification/Groundwater Assessment--determine the vertical and horizontal extent of C-8 impacted groundwater exceeding 1 ug/1 or as directed by the GIST at Dry Run Landfill. In Sections 6.2 through 6.4, discussions of the specific activities conducted to meet the requirements of the Consent Order are discussed along with the new data generated during these activities. In Section 6.5, the revised site conceptual model that better represents the current environmental setting (geology, hydrology, hydrogeology, groundwater flow, and water quality) and current human health and ecological exposure pathways for the conditions at and surrounding the Dry Run Landfill is presented. 6.2 Task A: Groundwater Well and Water-Use Surveying and C-8 Sampling The groundwater well and water-use survey and sampling within the one-mile radius of the Dry Run Landfill were completed on February 28, 2002. DuPont submitted the results of the one-mile radius survey to the GIST in April, 2002 (DuPont, 2002a). WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE UOOO'/l 50 C-8 Data Summary Report Dry Run Landfill Table 6.0 summarizes the off-site surveying and sampling program for the one-mile radius. A total of 64 homes were surveyed, and a total of 53 water sources (wells, cisterns and springs) were sampled. Thirteen wells, one cistern, and one spring sampled were used as drinking-water sources. Table 6.1 provides details for each sample collected including the C-8 concentration measured (ug/1). Figure 6.1 shows the locations of all samples collected, regardless of water use. Each colored circle represents a sampling location, and the color and size of the circle indicate the magnitude of the C-8 concentration measured. Small blue circles represent samples having C-8 concentrations less than 0.05 ug/1. Small green circles represent samples having C-8 concentrations ranging from to 0.05 to 1.0 ug/1. The C-8 concentrations measured in all the Dry Run Landfill one-mile radius samples were less than 1.0 ug/1. The highest C-8 concentrations measured for unused and non drinking-water sources were 0.974 and 0.54 ug/1. Seven of the 15 drinking-water samples were ND or NQ, and the range of C-8 concentrations in the other eight drinkingwater samples was between 0.0505 and 0.339 ug/1. Based on the very low C-8 concentrations measured when compared to the human health protective screening criteria for water (C-8 SL) of 150 ug/1, the GIST determined that no further surveying and sampling was needed. However, the GIST did require resampling of the eight drinkingwater sources with measurable concentrations of C-8. Residents of five of the eight drinking-water sources declined to have their water sources resampled. Resampling of the three drinking-water sources was completed in April 2002. C-8 concentrations ranged from NQ to 0.422 ug/1 in these samples (DuPont, 2002h). In addition, a surface-water sample was taken from the Lee Creek near the Graham residence, which is located a few miles west-northwest outside of the Dry Run one-mile radius. This sample was taken to evaluate C-8 quality in the Lee Creek before it discharges to the Ohio River. The Dry Run creek, which begins at the toe of the landfill, discharges surface water to the Lee Creek. The C-8 concentration measured was 0.28 ug/1 (DuPont, 2002h). At this same residence, a drinking-water well and a spring used for non-drinking-water purposes also were sampled and analyzed for C-8. The C-8 concentrations measured in these water sources were ND and 0.331 ug/1, respectively. 6.3 Task B: Assessment of Existing Groundwater and Surface-water Monitoring Data 6.3.1 Monitoring of C-8 in Groundwater and Surface Water at Dry Run Landfill Groundwater Monitoring The Consent Order required that all monitoring wells at Dry Run Landfill be sampled for C-8. Monthly C-8 sampling of groundwater began in December 2001, and quarterly sampling began in May 2002. Table 6.2 provides a list of the monitoring wells included in the groundwater monitoring program for Dry Run Landfill. Well construction data and groundwater elevation data also are provided in this table. At the time monitoring started, eight monitoring wells were installed at the Dry Run Landfill. Another seven wells were installed during 3Q02 as part of the C-8 plume delineation work plan, and these new wells were included in the monitoring program starting in 4Q02 (DuPont, 2002k). WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 51 000072 C-8 Data Summary Report Dry Run Landfill Figure 6.2 shows the location of the monitoring wells. Table 6.3 presents the C-8 concentrations measured in these monitoring wells, including C-8 data acquired prior to the issuing of the Consent Order. The most recent data are listed first for each well. The water-bearing units at Dry Run are named from ground surface to depth as the Overburden, and the A-Zone, the B-Zone, and the C-Zone. Wells monitoring the overburden include DRMW-6A, DRMW-12A, DRMW-12B, DRMW-13A, and DRMW-21A. DRMW-13A has shown the highest C-8 concentrations in overburden, ranging from 0.07 to 15 ug/1. This well is located at the toe of the landfill. DRMW-6A has shown a C-8 concentration range of 0.096 to 1.24 ug/1. DRMW-12A, DRMW-12B, and DRMW-21A have had much lower C8 concentrations, ranging from ND to 5.4 ug/1. Wells monitoring the A-Zone include DRMW-16B, DRMW-17B, DRMW-18B, DRMW-19B, and DRMW-20B. DRWM-14 is a continuous open hole; therefore, effectively monitors all water-bearing sandstone and siltstone units above the A-Zone as well as the A-Zone. All of these wells are new wells, except DRMW-14, and have only been sampled one time. C-8 concentrations in these new wells has ranged from ND to 0.155 ug/1. C-8 concentration in DRMW -14 has ranged from <0.1 to 2.5 ug/1. Wells monitoring the B-Zone include DRMW-12, DRMW-13, and DRMW-15. DRMW-12 has shown the lowest C-8 concentrations, ranging from <0.1 to 0.16. DRMW-15 has had higher C-8 concentrations ranging from 0.263 to 5.0 ug/1. DRMW-13, which is located at the toe of the landfill, has had the highest concentration of C-8, ranging from 3.6 to 20.9 ug/1. Only one well monitors the C-Zone, DRMW-21B. This is a new well that has only been sampled once, and the C-8 concentration measured was NQ. The next groundwater sampling event for the facility is scheduled for the first quarter 2003. Surface-water and Leachate Monitoring The Consent Order identified three outfalls at the Dry Run Landfill (regulated by WV/NPDES Permit No. WV0076244) where monthly C-8 sampling was to be performed, Outfalls 001, 003, and 004. (Outfall 002 is a required outfall sampling location as stated in the WV/NPDES permit. However, it was a temporary relocation of Outfall 001 and no longer exists). Outfall 001 collects stormwater and leachate. Outfalls 003 and 004 collect stormwater only. Monthly sampling of these three outfalls began in December 2001. In addition, there are five other locations that are sampled quarterly for C-8. These include Stream Samples-1 (SS-1) and -2 (SS-2), Pond Underdrain, Property Boundary, and DR Leachate. The locations of the surface-water and leachate sampling points are shown in Figure 6.2. The Property Boundary sample location is located along the western property boundary where the Dry Run creek crosses over the property boundary (see Figure 6.0). Table 6.4 provides the C-8 concentrations measured in the outfalls and leachate, including C-8 data acquired prior to the issuing of the Consent Order. The most recent data are listed first for each outfall. WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 52 000073 C-8 Data Summary Report Dry Run Landfill Outlet 004 is upgradient and flows into SS-1. SS-1, Outlet 001, Outlet 003, and Pond Underdrain flow into SS-2, which flows ultimately into the Property Boundary sampling point. Outlet 004 has had no-flow conditions in 10 of 12 sampling events. In the two events in which samples could be taken, the C-8 concentrations were 0.7 and 158 ug/1, making it difficult to determine a representative C-8 concentration for this location. SS-1 has shown the lowest C-8 concentrations, ranging from 0.54 to 1.63 ug/1. The C-8 concentrations in Outlet 003 and Property Boundary have been higher, ranging from 0.88 to 39 ug/1, although, Outlet 003 has had no-flow conditions in nine of the 12 sampling events. The Outlet 001, SS-2 and Pond Underdrain sampling locations have shown C-8 concentrations ranging from 4.6 to 87 ug/1. The DR Leachate sampling point, from which leachate is sampled, has shown the highest C-8 concentrations in surface water, ranging from 27.4 to 704 ug/1. The inactive lower half of the landfill is covered by geotextiles and geomembranes of the leachate collection system. Leachate at the Dry Run Landfill does not discharge to surface water. Leachate is captured by the leachate collection system at Dry Run and is transported to the Washington Works facility where it is treated. Outfall sampling for December 2002 has been completed, and the monitoring report will be issued to the GIST in February 2003. Outfall sampling for January 2003 has been completed, but the C-8 results have not yet been validated. The next monthly outfall sampling event is scheduled for February 2003. 6.4 Task C: Plume Identlfication/Groundwater Assessment Based on the data gaps identified in the Compilation of Historical C-8 Data Report (DuPont, 2002b), the C-8 Plume Identification/Groundwater Assessment Work Plan was developed and submitted to the GIST (DuPont, 2002e). Included in this work plan were specific activities recommended to fill the data gaps. In the following sections, each of the activities recommended in the C-8 plume delineation work plan is summarized briefly. Details of the activity status and the data acquired are then presented. 6.4.1 C-8 Monitoring in Groundwater and Surface Water at Dry Run Landfill Continuing to monitor C-8 in groundwater in the overburden and in the underlying bedrock aquifer (utilizing the newly installed monitoring wells), and in surface water at existing locations identified in the Consent Order, was an activity recommended in the C-8 plume delineation work plan. The results of continued monitoring of groundwater and surface water are presented in Section 6.3.1. Monitoring of C-8 in groundwater continues on a quarterly basis, while surface-water monitoring of C-8 is conducted on a monthly basis. In addition, sampling of Lee Creek, which crosses the site boundary, also was recommended in the C-8 plume delineation work plan. This sample was recommended to evaluate C-8 concentrations further downstream from the landfill than pre-existing surface-water monitoring points. The Dry Run creek begins at the toe of the landfill and then discharges to Lee Creek, which discharges to the Ohio River. This sample was collected, and the C-8 results are presented in Section 6.3.1. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 53 000074 C-8 Data Summary Report Dry Run Landfill 6.4.2 Surface-water Field Reconnaissance at the Dry Run Landfill Conducting field reconnaissance to identify additional surface-water features located at the Dry Run Landfill and sampling surface water from new locations identified during this effort was a C-8 plume delineation recommended activity. Field reconnaissance was performed (during drought conditions) and no new surface-water features were identified beyond those locations that are currently sampled. 6.4.3 Installation of New Wells at Dry Run Landfill Six additional well clusters (overburden and bedrock) were installed as proposed in the C-8 plume delineation work plan to better characterize the bedrock at the Dry Run Landfill, to further delineate C-8 concentrations in groundwater and to re-evaluate groundwater flow direction. During implementation of field activities, overburden was minimal or was dry at most locations; therefore, five bedrock wells and one well cluster were installed. Figure 6.2 shows the locations of all monitoring well at the Dry Run Landfill including the locations of the newly installed monitoring wells. Well construction diagrams for the new wells, are provided in Appendix D. The geological logs for the five bedrock wells and the one well cluster installed in 3Q02 confirm previous interpretations of subsurface conditions at the Dry Run Landfill. Clay, silty clay, or fill material is underlain by bedrock, consisting of alternating layers of sandstone and siltstone separated by layers of shale. Further, the new geologic logs also confirm that the lithologic units are essentially horizontal. New to our geological interpretation is the identification of three individual water-bearing bedrock zones labeled as A-Zone, B-Zone, and C-Zone. These zones are discussed in detail in Section 6.5.1. 6.4.4 Dry Run Site Conceptual Model Refinement The final recommended activity for the Dry Run Landfill was the integration of all the new data gathered during completion of Tasks A, B, and C into a revised SCM. This activity has been completed, and the revised SCM is presented in the following section. 6.5 Revised Site Conceptual Model The revised SCM ideally should accurately represent the current environmental setting (geology, hydrology, hydrogeology, groundwater flow, and water quality) and current human health and ecological exposure pathways for the conditions at and surrounding the Dry Run Landfill. The following sections present the revised SCM in detail. 6.5.1 Current Environmental Setting Geology The locations of four cross-sections developed for the Dry Run Landfill are shown in Figure 6.3. Two cross-sections, A-A' and B-B', were presented in the Compilation of Historical Data Report (DuPont, 2002b). Cross-section A-A' was based on minimal data. This original cross-section has been abandoned, and a new cross-section A-A', which includes many of the new wells installed in 3Q02, was generated. This new cross-section WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 54 000075 C-8 Data Summary Report Dry Run Landfill A-A', which runs northwest to south east along the northeast side of the landfill, is presented in Figure 6.4. Cross-section B-B', running north to south across the toe of the landfill, has been modified slightly but the basic information in the cross-section remain. The modified cross-section B-B' is presented in Figure 6.5. In addition, cross-sections A-C' and D-B' (see Figures 6.6 and 6.7), which include the new wells, were developed. Cross-section A-C runs from the northwest to the southeast on the southwest side of the landfill. Cross-section D-B' runs across the center of the landfill crossing from the northeast to the southwest. The Dry Run Landfill is situated on a heavily dissected plateau consisting of several steep V-shaped valleys. Residual soil covers most landfill areas. In general, the soil at the site has been described as residual in nature, consisting primarily of heavy clays derived from the weathering of shale. A geotechnical investigation of the overburden underlying the Dry Run Landfill was completed by DuPont (1996). The investigation consisted of advancing soil test borings, test pits, laboratory testing of soil physical properties, stability analyses, and settlement analyses. DuPont (1996) determined that the natural residual soil underlying the landfilled materials consisted of stiff to very hard silty clay and clayey silt with occasional rock fragments and a trace of sand. The thickness of this natural soil ranged from 12 to 28 feet in the test borings within the landfilled area. In 1989, a monitoring well installation program, performed by Tetra Tech Richardson Inc., indicated similar silty clay and weathered shale overburden. Currently, there are five monitoring wells that monitor the water-bearing overburden (DRMW-6A, DRMW-12A, DRMW-12B, DRMW-13A, and DRMW-21A) at the Dry Run Landfill (see Figures 6.4 through 6.6). Completion depths for these wells range from approximately 12 to 20 feet bgs. The underlying bedrock at the Dry Run Landfill consists of inter-bedded red and varicolored sandy or calcareous shales, and gray, green, and brown sandstones and/or siltstones of the Permian age Dunkard Group. Based on the new geological data, three separate water-bearing siltstones and/or sandstone units have been identified within the bedrock at Dry Run. These zones are shown on the cross-sections when possible. These are labeled the A-Zone, the B-Zone, and the C-Zone, with the A-Zone being the uppermost unit and the C-Zone being the lowest unit bgs. The A-Zone is laterally continuous under most of the landfill area, while the B-Zone is known to be laterally continuous under the toe of the landfill in the northwest. None of the new wells were drilled deep enough to encounter the C-Zone. The B-Zone was not observed in DRMW-14, the well located furthest to the southeast. However, no additional sandstone or siltstone units were encountered under the A-Zone at the projected elevation of the B-Zone. The C-Zone was only encountered at the furthest northwest location, DRMW-21B. Hydrology, Hydrogeology and Groundwater Flow Hydrology The Dry Run Landfill is situated on a heavily dissected plateau consisting of several steep V-shaped valleys. The Dry Run creek drains the valley in which the landfill is located. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000076 55 C-8 Data Summary Report Dry Run Landfill Many small tributaries discharge from the nearby valleys into the Dry Run creek before it joins up with the North Fork of Lee Creek. The installation of landfill cap and a leachate collection system at the Dry Run Landfill encompassing the inactive lower half of the landfill was completed by Potesta & Associates, Inc. in 1999. Leachate from the landfill discharges into a leachate collection sump located northwest of the landfill (see Figure 6.2) through perforated pipes buried at the low edge of the fill area. The leachate is pumped from the collection sump to a 50,000-gallon collection tank located at the top of the hill. Leachate is pumped from the collection tank to a tanker truck, which is then hauled to the facility for treatment in the wastewater treatment plant. Six surface-water sampling points are located near the toe of the landfill (see Figure 6.2). Four of these six points are man-made monitoring points associated with the leachate collection system and the lower landfill cap. Two points, SS-1 and SS-2, monitor surface water in streams located near the toe of the landfill. Ultimately, all of these surface-water monitoring points discharge into Dry Run creek. Dry Run creek ultimately discharges into Lee Creek. Lee Creek discharges into the Ohio River. Hydrogeology Groundwater occurs in the overburden and the underlying bedrock aquifers. A total of 22 monitoring wells were installed at the Dry Run Landfill to monitor the overburden and bedrock aquifers. Currently, five overburden wells and 10 bedrock wells still exist. The other seven wells were abandoned in 1999 by Potesta & Associates, Inc. as required by the permit because these wells were not being utilized for quarterly monitoring (Potesta & Associates, 1999). Groundwater Flow In the 4Q02 Surface Water and Groundwater report (DuPont, 2002k), revised groundwater elevation maps for 2Q02, 3Q02 and 4Q02 were generated. These maps did not include data from the new wells because the site conceptual model had not yet been revised. Using the new geological interpretation of three distinct water-bearing zones and using groundwater elevation data from the new wells, new groundwater elevation contour maps were constructed for the A-Zone and the B-Zone using 4Q02 data. These maps are presented in Figures 6.8 and 6.9. The groundwater elevation map for the A-Zone (see Figure 6.8) shows that overall the direction of groundwater flow is toward the west. DRMW-14 was not used in the construction of this map because it is an open hole well and water levels measured in this well may be influenced by shallow water bearing zones that are higher in elevation than the A-Zone. Figure 6.9 shows the direction of groundwater flow in the B-Zone. The groundwater contour lines on this map are dashed because there are very limited data for the zone. However, groundwater flow direction in this zone also is generally toward the west. Groundwater flow directions in the underlying the C-Zone cannot be determined because there is only one well in the zone. However, a downward vertical gradient is indicated from the A-Zone to the B-Zone and to the C-Zone based on groundwater elevations observed in the three zones. WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 000077 56 C-8 Data Summary Report Dry Run Landfill Water Quality Groundwater Quality Groundwater quality data for the Dry Run Landfill were presented in detail in Section 6.3.1. Fifteen wells monitor the overburden and the three underlying water-bearing zones (A-Zone, B-Zone, and C-Zone) at the Dry Run Landfill. The highest concentrations of C-8 measured in the overburden and underlying zones are found in the wells that are the closest to the toe of the landfill. The highest C-8 concentration measured in groundwater at the Dry Run Landfill is 20.9 ug/1, significantly lower that the CATT-established C-8 SL of 150 ug/1. The highest concentration of C-8 in groundwater used as drinking-water source by residences located within a one-mile radius of the landfill was 0.422 ug/1. The highest concentrations of C-8 in groundwater used as non-drinking-water and unused sources by residences located within a one-mile radius of the landfill was 0.54 and 0.974 ug/1, respectively. These values are also significantly lower that the C-8 SL of 150 ug/1. Surface-water and Leachate Quality Surface-water and leachate quality was discussed in detail in Section 6.3.1. Surfacewater and leachate sampling points have been monitored at the Dry Run Landfill. The leachate samples have shown the highest C-8 concentrations with a maximum concentration of 704 ug/1. It is expected that leachate from the landfill would have the highest concentration of C-8 because the source for the C-8 is likely the landfilled materials. Leachate at the Dry Run Landfill does not discharge to surface water. It is collected at the landfill and is treated at the facility. Six of the surface-water sampling points are located in the vicinity of the toe of the landfill, and four of these are associated with the landfill cap. The four sampling points associated with the landfill cap flow into the other two sampling points located on streams that discharge stormwater from the area. The maximum concentration measured for these six sampling points has been 87 ug/1. The other sampling point is located at the western property boundary. The highest concentration of C-8 observed at this location has been 39 ug/1, although, seven of the 11 samples collected from this point have had C-8 concentration less than 10 ug/1. With the exception of the leachate samples, the C-8 concentration of all surface-water samples have been less than the CATT-established C-8 SL of 150 ug/1. Further, these concentrations are significantly less than the Aquatic Life Advisory Concentration for C-8 (C-8 ALAC) of 1,360 ug/1. 6.5.2 Current Human Health and Ecological Exposure Pathways The main objective of the Consent Order was to determine whether there has been an impact on human health and the environment as a result of releases of C-8 to the environment from DuPont operations at the Washington Works facility and the associated landfills (Local, Letart, and Dry Run). To meet this objective, human health and ecological exposure pathways both on-site (at the Dry Run Landfill) and off-site (adjacent to the Dry Run Landfill property) must be evaluated. The human health and ecological exposure pathway sections below describe the potential exposure routes for human and ecological receptors on- and off-site. Potential exposure routes were WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000078 57 C-8 Data Summary Report Dry Run Landfill evaluated and classified as complete or incomplete. Table 6.5 summarizes the human health and ecological exposure pathway evaluation for the Dry Run Landfill. To be conservative, for each complete exposure pathway, the maximum C-8 concentration measured in the C-8 impacted media is compared to the C-8 SL, regardless of media type. On-Site Human Health and Ecological Exposure Pathways Current Environmental Setting The on-site current human health and ecological exposure pathways section describes the potential exposure routes for human and ecological receptors that are found at the Dry Run Landfill. On-site human receptors include authorized facility workers and facility visitors. Ecological receptors include animals living within the landfill boundaries. Potential exposure routes were evaluated and classified as complete or incomplete. Access to the Dry Run Landfill by is controlled by electronic gates on the major roads and locked gates on smaller roads. In addition, because the landfill is active, there is a crew of workers in the central portion of the landfill area during normal working hours. The institutional controls and the daily activity discourages trespassers on the site. Direct contact with landfill materials or soils impacted by the materials in the inactive, lower half of the landfill is incomplete due to the leachate collection system's geotextile and geomembrane cover. However, direct contact with landfilled materials or soils impacted by the materials at the active, upper half of the landfill is a complete pathway and is limited to the workers in active portions of the landfill. Precipitation falling in the upper half of the landfill may infiltrate the soil and vegetative cover and contact the landfilled materials as it migrates downward. However, this impacted surface water flowing within the landfill will be collected by the leachate collection system. Contact with leachate captured at the landfill is an incomplete pathway. If this impacted surface water migrates downward through the landfilled materials, it may eventually contact the underlying shales and sandstone of the bedrock and migrate downward as groundwater into the bedrock aquifer. Contact with groundwater is considered to be an incomplete exposure route. The water-bearing zones that are monitored at the landfill are located at several hundreds of feet bgs at the upper end of the landfill. In the lower end of the landfill, the A-Zone is exposed at the surface. However, no seeps were observed in the areas where this zone is exposed. In addition, in the lower end of the landfill, the depth to groundwater in the overburden is 5 to 8 feet bgs; therefore, contact with this groundwater as an exposure pathway is also incomplete. Contact with C-8 impacted surface water near the toe of the landfill is considered a complete exposure pathway. However, this exposure pathway is limited because site workers follow health and safety procedures (i.e., personal protective equipment) when managing surface water at the site. The C-8 concentration measured in surface water in this area has ranged from 0.54 to 87 ug/1, less than the C-8 SL established by the CATT and significantly less that the C-8 ALAC of 1,360 ug/1. Contact with C-8 impacted surface water at the property boundary is also a complete exposure pathway for human and ecological receptors. C-8 concentrations at this location have ranged from 0.88 to 39 ug/1, which are below the C-8 SL and are significantly lower than the C-8 ALAC. In WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 58 000079 C-8 Data Summary Report Dry Run Landfill addition, C-8 concentrations measured in the seven of the 11 samples from this location were less than 10 ug/1. Therefore, although this exposure pathway is complete, it is limited due to the low C-8 concentrations measured. Off-site Human Health and Ecological Exposure Pathways Off-site human receptors include residents using the water sources sampled during the groundwater well and water-use survey. Ecological receptors include livestock using the water sources sampled during the groundwater well and water-use survey. West Virginia One-Mile Radius Groundwater and Surface W ater Direct exposure to C-8 impacted surface water and groundwater is considered to be an incomplete pathway in situations where the water source is not used. The pathway is considered to be a complete pathway when the water source is used but not for drinkingwater purposes although the exposure is considered to be minimal because the water is not ingested. The highest C-8 concentration in a non-drinking-water sample was 0.54 ug/1, well below the C-8 SL of 150 ug/1 (WVDEP, 2002). The pathway is considered to be complete if the well is used for drinking water. The highest C-8 concentration measured in drinking water was 0.422 ug/1, significantly lower than the CATT-established C-8 SL of 150 ug/1. Therefore, the pathway is complete, and exposure is considered to be limited due to the low C-8 concentrations measured. Outside of the one-mile radius, a surface-water sample was taken from the Lee Creek near a private residence. The C-8 concentration measured in the Lee Creek was 0.28 ug/1 (DuPont, 2002g). At this same residence, a drinking-water well and a spring used for non-drinking-water purposes also were sampled and analyzed for C-8. The C-8 concentrations measured in these water sources were ND and 0.331 ug/1, respectively. The exposure pathways for these water sources are complete. However, all three of these concentrations measured are significantly lower than the C-8 SL. 6.6 Dry Run Landfill Summary Many different activities have been conducted at and around the Dry Run Landfill in order to determine whether there has been an impact on human health and the environment as a result of releases of C-8 to the environment from the landfill. The C-8 concentration in groundwater and surface water from many sources (on-site, off-site, monitoring wells, production wells, private wells, springs, and cisterns) was measured. Based on all of the data evaluated for the Dry Run Landfill, the following observation were made: The current exposure pathways are incomplete for human and ecological receptors contact with on-site leachate and groundwater. Human and ecological receptor contact with C-8 impacted landfill materials, soils, and surface water are currently complete exposure pathways. However, these pathways are considered to be minimal because of institutional controls on the property, personal protective equipment worn, and health and safety procedures that are in place and followed when working with or around the active landfill and when managing the leachate collected at the Dry Run Landfill and surface water. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 59 000030 C-8 Data Summary Report Dry Run Landfill Contact with surface water exiting the site that has been impacted by C-8 is also currently a complete exposure pathway for human and ecological receptors. The highest C-8 concentration measured in surface water exiting the site was 39 ug/1, which is lower than the CATT-established C-8 SL of 150 ug/1 and lower than the C-8 ALAC of 1,360 ug/1 (Menzie-Cura & Associates, 2002). C-8 concentrations measured in seven of the samples taken at the property boundary were less than 10 ug/1, indicating that while this exposure pathway is complete, exposure is limited because of the low concentrations of C-8 detected. Current off-site exposure pathways for human and ecological receptors that are complete but limited, due to the very low C-8 concentration measured, include residential drinking and non-drinking-water sources. For the drinking and non drinking-water sources, the highest C-8 concentration measured were 0.422 and 0.54 ug/1 respectively, which are well below the C-8 SL of 150 ug/1 and the C-8 ALAC of 1,360 ug/1 (WV DEP, 2002; Menzie-Cura & Associates, 2002). Evaluation of the C-8 results measured at the Dry Run Landfill, of the groundwater flow direction at the landfill, and of the one-mile radius C-8 results shows that C-8 impacted groundwater is not migrating off-site. The on-site C-8 results for groundwater and surface-water support water transport as the migration pathway for C-8 from C-8 containing landfilled materials to surface water and groundwater. However, the Dry Run Landfill is located within eight miles southwest of the facility. Therefore, air transport of C-8 by air emissions from the facility cannot completely be ruled out, and may be the source of C-8 for the very low concentrations measured within the Dry Run one-mile sampling area. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE o m o si 60 C-8 Data Summary Report References 7.0 REFERENCES DuPont 1990. Washington Works 1990 Preliminary Hydrogeologic Assessment. Solid Waste & Geological Engineering Department. _ _ _ _ _ 1992. Verification Investigation E.I. DuPont de Nemours Co. Washington Works April 1992. (Vol. 1). _____ 1996. Report o f Geotechnical Investigation Dry Run Landfill, Washington Works Main Plant, Parkersburg, WV. Geotechnical Group, Civil Engineering Systems, DuPont Engineering. ______ 1999. RCRA Facility Investigation Report, DuPont Washington Works, June 30, 1999. DuPont Corporate Remediation Group and URS Diamond. ______2000. Letart Landfill Groundwater Protection Plan SW/NPDES Permit No. WV0076066, January 7, 2000. DuPont Corporate Remediation Group and URS Diamond. ______2001. Certification Report Letart Landfill Cap Construction, June 2001. Corporate Remediation Group. ______2002a. One-Mile Radius Survey and C-8 Sampling Report and Ohio River Public Water Supply Sampling, DuPont Washington Works (December 2001-February 2002) January 2002. DuPont Corporate Remediation Group and URS Diamond. ______2002b. Compilation o f Historical C-8 Data, DuPont Washington Works Main Plant and Landfills January 2002. DuPont Corporate Remediation Group and URS Diamond. ______2002c. Proposed Groundwater Monitoring Planfor Washington Works Facility Plant and Landfills January 2002. DuPont Corporate Remediation Group and URS Diamond. ______2002d. Email with attached map from Andrew Hartten of DuPont to the Groundwater Investigation Steering Team 2/25/02. _____ 2002e. C-8 Plume Identification/Groundwater Assessment Work Plan, DuPont Washington Works Facility and Local, Letart and Dry Run Landfills May 2002. DuPont Corporate Remediation Group and URS Diamond. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 0000S2 61 C-8 Data Summary Report References 2002f. January 2002 Groundwater Investigation Quality Assurance Project Plan for Washington Works Plant Washington, WV, January 2002. DuPont Corporate Remediation Group and URS Diamond. 2002g. May 2002 Groundwater Investigation Quality Assurance Project Plan Addendumfor Washington Works Plant Washington, WV, January 2002. DuPont Corporate Remediation Group and URS Diamond. _2002h. Two-Mile Radius Survey and C-8 Sampling, DuPont Washington Works Facility/Local Landfill, West Virginia (March-May 2002) August 2002. DuPont Corporate Remediation Group and URS Diamond. _2002i. One-Mile Radius Survey and C-8 Sampling Report, Washington County, Ohio (March - June 2002) August 2002. DuPont Corporate Remediation Group and URS Diamond. _2002j. Two-Mile Radius Survey and C-8 Sampling Report, Washington County, Ohio (June - September 2002) December 2002. DuPont Corporate Remediation Group and URS Diamond. _2002k. Fourth Quarter 2002 C-8 Surface Water and Groundwater Monitoring Report For Washington Works Facility and Local, Letart and Dry Run Landfills Washington, WV December 2002. DuPont Corporate Remediation Group and URS Diamond. ______20021. Ohio River Water Sampling Results, Washington Works Facility and the Letart Landfill November 2002. DuPont Corporate Remediation Group and URS Diamond. ______2002m. 3Q02 and 4Q02 Public Water Supply Results, West Virginia and Ohio, DuPont Washington Works, Washington WV November 2002. DuPont Corporate Remediation Group and URS Diamond. ______2003a. Revised Groundwater Flow Model, DuPont Washington Works, Washington, WV January 2003. DuPont Corporate Remediation Group and URS Diamond. ______ 2003b. November 2002 Surface Water Monitoring Report For Washington Works Facility and Local, Letart and Dry Run Landfills Washington, WV January 2003. DuPont Corporate Remediation Group and URS Diamond. Exygen. 2002. Personal Communication between John Flaherty, Operations Manager, Exygen Research, Inc. and Michael D. Aucoin, Project Chemist, URS Diamond. WWK-C-8 Data Summary - text final Feb. 5, 03 Wilmington, DE 000083 62 C-8 Data Summary Report References Menzie-Cura & Associates, Inc. 2002. Final Report, C8 Assessment o f Toxicity team (CATT) Report Addendum Aquatic Life Advisory Concentration for C8. Potesta & Associates, Inc. 1999. Monitoring Wells MW-1, MW-1A, MW-4, MW-4A, MW-6, MW-10, MW-10 Abandonment Report, Dry Run Landfill, DuPont Washington Works. March 1999. Simard, C. M. 1989. Geological History of the Lower Terraces and Floodplains o f the Upper Ohio River Valley, Open File Report, West Virginia Geological Survey, 160 p. Schultz, R.A. 1984. Groundwater Hydrology of the Minor Tributary Basins o f the Ohio River, West Virginia. Tetra Tech Richardson. 1990. Monitoring Well Installation Program at Letart Landfill Summary Report, August 1990. USEPA. 1994. Region III Modifications to National Functional Guidelinesfor Organic Data Review. WVDEP. 2002. Final Ammonium Perfuorooctanonate (C8) Assessment of Toxicity Team (CATT) Report. August 2002. West Virginia Department of Environmental Protection WWK-C-8 Data Summary -- text final Feb. 5, 03 Wilmington, DE 000034 63 TABLES ssoooo Table 3.0 Summary of Off-site Sampling Program (C-8 Sampling) DuPont Washington Works Facility and Local Landfill Washington, WV RESIDENTIAL SAMPLING FOR 1-MILE RADIUS . > . / (A (1) E Number of homes contacted (1) 311 0 1 Number of homes surveyed (1) 269 Number of wells identified (2> 51 tn US Number of wells sampled <2) 34 5 Number of wells sampled that are used for drinking water 6 to Number of cisterns identified (2) 17 L_ *<-D* Number of cisterns sampled (2) 6 Number of cisterns sampled that are used for drinking water 0 tn Number of springs identified (2) 6 O) c `C Number of springs sampled (2) 4 Q. CO Number of springs sampled that are used for drinking water 0 tn _g> o Total number of samples 44 E (0 CO Total number of collected samples used for drinking water 6 Note: Field duplicates not considered in sample count. (1) During this investigation, homeowners/residents identified within the sampling radius were contacted to determine residential water usage. Up to two contacts were attempted at each residence. After the second contact attempt, a voluntary survey was left at the residence. Because not all homeowners/residences responded to the survey, the number of residences surveyed is less than the number of homes contacted. (2) Some water sources (e.g. wells, cisterns, springs) Identified during the survey were not sampled. In many cases, sampling of these water sources was refused by the homeowners/residents. In other cases, the water sources were either not accessible or damaged. As a consequence, the number of water sources sampled was less than the number of water sources identified. 0000S6 2/4/2003 1 of 1 Tab 3.0 Consent Order T&F.xIs Table 3.1 Summary of C-8 Analytical Results In Groundwater and Surface Water (ug/l) Washington Works Facility and Local Landfill (Off-site Wells, Springs, and Cisterns - One Mile Radius) Washington, WV Sample ID -AHHTft OS-BALSEYAR OS-BALSEYAR OS-CHRISTMANS OS-CHRISTM ANS OS-SMITHMT OS-VINCENTS OS-VINCENTS OS-WILCOXA OS-WILCOXA OS-AINSLEYB OS-BEEBEED OS-BLANKENSHIPR OS-BURCHARDA OS-BURDE7TEP OS-CAINM OS-CAYTONW OS-COCHRANG OS-CORBITTG OS-COWANJW OS-CREELK1 OS-CREELK2 OS-DAVISJ OS-EAKINE OS-FIKER OS-FURBEEC OS-HENDRICKSR OS-LAKEWASHC1 OS-LAKEWASHC2 OS-LAWSONDH OS-MILLERJ OS-MILLSS OS-NEWHOUSES OS-PARSONS D OS-RICHARDSV OS-RIDDLED1 OS-WAYBRIGHTO OS-WHITAKERK Sample Date 12/19/2001 12/21/2001 4/11/2002 12/21/2001 4/11/2002 2/5/2002 12/17/2001 4/11/2002 1/28/2002 4/14/2002 1/28/2002 1/15/2002 2/21/2002 1/9/2002 1/10/2002 1/27/2002 1/25/2002 1/25/2002 1/23/2002 3/27/2002 1/27/2002 1/27/2002 1/9/2002 1/9/2002 1/23/2002 1/23/2002 1/25/2002 1/14/2002 1/15/2002 1/8/2002 1/14/2002 12/17/2001 1/27/2002 2/5/2002 12/17/2001 2/12/2002 1/15/2002 1/10/2002 OS-LAWSONDH2 OS-RIDDLED2 OS-SHOCKEY G OS-TALLHAMER 1/10/2002 2/12/2002 1/27/2002 1/28/2002 C-8 ug/l 2.8 1.74 2.48 0.328 0.526 1.33 1.1 1.36 1.72 1.74 1.83 3.2 0.715 0.416 1.7 2.93 3.63 1.3 0.945 14.3 2.7 7.47 3.36 0.569 0.32 5.07 1.72 0.347 0.867 9.56 3.94 0.932 0.304 3.44 2.37 3.24 0.252 2.3 10.9 2.8 1.33 T63 Water Use * Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Misc. Unused Water Cattle Unused Unused Misc. Unused Unused Misc. Unused Unused Misc. Unused Unused Unused Unused Unused Unused Water Cattle Sample Type Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Spring Spring Spring Spring 1/29/2003 4:25 PM 1 012 Tab 3.1 Consent Order T&F.xIs 000087 Table 3.1 Summary of C-8 Analytical Results In Groundwater and Surface Water (ug/l) Washington Works Facility and Local Landfill (Off-site Wells, Springs, and Cisterns - One Mile Radius) Washington, WV Sample ID Sample Date OS-ALKIREF OS-COLLINSC OS-PORTEREL OS-SMITHMM OS-THOMPSONB OS-WATKINSCL 1/27/2002 12/18/2001 12/19/2001 12/17/2001 12/17/2001 12717/2001 C-8 uo/l 3.15 1.56 0.561 2.48 3.52 T3S Water Use * Unused Misc. Misc. Misc. Water Cattle Misc. Sample Type Cistern Cistern Cistern Cistern Cistern Cistern * Drinking Water (highlighted in bold blue) indicates human consumption. Non-drinking Water uses include livestock watering, gardening and any other non-human consumption water uses. Misc. = Miscellaneous water use is not used for drinking. Data highlighted in yellow are results for water sources located within the one-mile radius that were resampled during the two-mile radius sampling event. 1/29/2003 4:25 PM 2 of 2 Tab 3.1 Consent Order T&F.xIs ooooss Table 3.2 Summary of Off-site Sampling Program (C-8 Sampling) Washington Works Facility and Local Landfill Two-mile Radius DuPont Washington Works Wells Homes RESIDENTIAL SAMPLING FOR THE 2-MILE RADIUS '- 'V Number of homes contacted (1> Number of homes surveyed (1) Number of wells identified (2) Number of wells in sampled (2) 667 109 98 52 Number of wells sampled that are used for drinking water Number of cisterns identified (2) Number of cisterns sampled (2) 17 17 8 Number of cisterns sampled that are used for drinking water Number of springs identified (2) Number of springs sampled (2) 0 7 5 Cisterns Samples Springs Number of springs sampled that are used for drinking water Total number of samples 1 65 Total number of collected samples used for drinking water 18 Note: Field duplicates not considered in sample count. (1) During this investigation, homeowners/residents identified within the sampling radius were contacted to determine residential water usage. Up to two contacts were attempted at each residence. After the second contact attempt, a voluntary survey was left at the residence. Because not all homeownecs/residences to the survey, the number of residences surveyed is less than the number of homes contacted. <2)Some water sources (e.g. wells, cisterns, springs) identified during the survey were not sampled. In many cases, sampling of these water sources was refused by the homeowners/residents. In other cases, the water sources were either not accessible or damaged. As a consequence, the number of water sources sampled was less than the number of water sources identified. 0000S9 2/4/2003 1 of 1 Tab 3.2 Consent Order T&F.xis Table 3.3 Summary of C-8 Analytical Results in Groundwater and Surface Water (Off-site Weils, Springs, and Cisterns) Washington Works Facility and Local Landfill Two-mile Radius Washington, WV 2-Mile Sample ID OS-HAMILTONF OS-LINGERAC1 OS-STEPHENSDS OS-STEPHENSEE OS-MCMAHANGE OS-BAKERER OS-JAMESONRD OS-COLVINRL OS-FOUTTBL OS-NAYJL OS-BOSOEC OS-HESSOK OS-NEWBERRYPC OS-MILLSLE OS-SMITHPL OS-PHILIPSAE OS-COLEMANC1 OS-JOHNSONL1 OS-WEATHERHOLTLJ OS-GARNESAL OS-RHOADESRW OS-WIGALJ OS-YOSTJ OS-GOLDSMITHML OS-SAMSCW OS-SACCHID OS-JOHNSONL2 OS-LINGERAC2 OS-ARNOLDWC OS-BARKERC OS-WOLFEDJ OS-WYATTVE OS-DOTSONH OS-EATONJD OS-HAMMONDE OS-CAMPBELLG OS-SARTORL OS-GLASSC OS-MATHEWSJR OS-REEDERHJ OS-MILLSS OS-TUCKERCM OS-TALLMANE OS-LlFEM OS-MOREHEADV OS-NORMANE Date 3/14/2002 3/14/2002 3/14/2002 3/14/2002 3/15/2002 3/18/2002 3/18/2002 3/19/2002 3/19/2002 3/19/2002 3/28/2002 3/28/2002 4/5/2002 4/18/2002 4/24/2002 4/25/2002 6/4/2002 3/14/2002 3/20/2002 4/3/2002 4/29/2002 5/8/2002 5/14/2002 5/20/2002 5/20/2002 5/31/2002 3/14/2002 3/14/2002 4/8/2002 4/8/2002 4/8/2002 4/12/2002 5/8/2002 5/8/2002 5/10/2002 5/13/2002 5/13/2002 5/14/2002 5/14/2002 5/14/2002 5/21/2002 5/21/2002 5/22/2002 5/23/2002 5/29/2002 5/29/2002 C-8 ug/L 0.737 ND (<0.010) 0.625 0.229 ND (<0.010) NQ (<0.050) ND (<0.010) 0.242 0.899 0.465 NQ (<0.050) NQ (<0.050) 0.386 ND (<0.010) ND (<0.010) 0.73 ND (<0.010) ND (<0.010) 0.078 1.3 1.56 0.625 0.081 0.874 1.2 ND (<0.010) 1.08 1.36 2 0.706 0.17 1.19 0.164 ND (<0.010) 0.074 0.091 0.927 0.425 0.781 1.17 1.57 0.095 0.325 0.257 1.19 0.592 Water Use* Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Sample Type Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well 1/30/2003 1 of 2 Tab 3.3 Consent Order T&F.xIs 000090 Table 3.3 Summary of C-8 Analytical Results in Groundwater and Surface Water (Off-site Wells, Springs, and Cisterns) Washington Works Facility and Local Landfill Two-mile Radius Washington, WV 2-Mile Sample ID OS-BIRAMB OS-VAUGHNDE OS-MITCHELLL OS-SMITHLK OS-WRIGHTW OS-RICHARDSC OS-STUTTLERLR OS-BLOOMERCG OS-BURTONDE OS-RITTENHOUSE OS-ARTHURRS OS-WALTERSMM OS-WILLISJL OS-HERTZTL OS-BLUERE OS-EDDYMM1 OS-EDDYMM2 OS-PUGHJA OS-NUTTERK Date 5/29/2002 5/30/2002 5/30/2002 5/31/2002 6/3/2002 6/3/2002 3/27/2002 3/21/2002 4/16/2002 4/16/2002 3/20/2002 3/22/2002 4/24/2002 4/25/2002 4/18/2002 4/24/2002 4/24/2002 5/14/2002 5/22/2002 C-8 ug/L 0.268 ND (<0.010) 1.26 0.092 1.07 1.52 1.8 0.857 0.823 0.898 2.32 1.39 0.772 1.67 0.447 2.27 1.84 NQ (<0.050) 0.174 Water Use* Unused Unused Unused Unused Unused Unused Drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Unused Non-drinking Water Non-drinking Water Non-drinking Water Unused Unused Unused Unused Unused Sample Type Well Well Well Well Well Well Spring Spring Spring Spring Spring Cistern Cistern Cistern Cistern Cistern Cistern Cistern Cistern * Drinking W ater (highlighted in bold blue) indicates human consumption. Non-drinking Water uses include livestock watering, gardening and any other non-human consumption water uses. ND = Not Detected at or above the limit of detection (LOD). The listed LOD is approximate and varies by instrument and over time. NQ = Not Quantifiable. Detected at a concentration above the LOD and below the limit of quantification (LOQ). 1/30/2003 2 of 2 Tab 3.3 Consent Order T&F.xIs 0000S1 jj- W x u jTW v/ ^ j i/ifo W -}0 J o r ^ o m A II 000032 Table 3.4 Summary of Off-site Sampling Program (C-8 Sampling) Ohio One-mile Radius Residential Sampling DuPont Washington Works Wells Homes RESIDENTIAL SAMPLING FOR OHIO 1-MILE RADIUS Number of homes contacted (1) Number of homes surveyed (1) Number of wells identified (2) Number of wells sampled (2) Number of wells sampled that are used for drinking water Number of cisterns identified (2) Number of cisterns sampled that are used for drinking w a te r(2) Number of cisterns sampled that are used for drinking water Number of springs identified (2) Number of springs sampled <2) Number of springs sampled that are used for drinking water 361 150 78 47 17 16 5 0 15 15 1 Cisterns Samples Other Springs Pool Total number of samples 1 68 Total number of collected samples used for drinking water 18 Note: Field duplicates not considered in sample count. (1) During this investigation, homeowners/residents identified within the sampling radius were contacted to determine residential water usage. Up to two contacts were attempted at each residence. After the second contact attempt, a voluntary survey was left at the residence. Because not all homeowners/residences to the survey, the number of residences surveyed is less than the number of homes contacted (2)Some water sources (e.g. wells, cisterns, springs) identified during the survey were not sampled. In many cases, sampling of these water sources was refused by the homeowners/residents. In other cases, the water sources were either not accessible or damaged. As a consequence, the number of water sources samplec was less than the number of water sources identified. 000093 2/4/2003 1 of 1 Tab 3.4 Consent Order T&F.xIs Table 3.5 Summary of C-8 Analytical Results in Groundwater and Surface Water Ohio One-mile Radius Residential Sampling 1-Mile Sample ID OS-MARCUMLL OS-KANITZKP OS-KANITZKP (dup) OS-RUMERJH OS-RYANSP OS-SWAINPH OS-WILCOXENWT OS-COLLINSRL OS-FARLEYFL OS-PRICEFL OS-HORNBECKLK OS-LEGLEITNERJK OS-MATHENYBL OS-MATHENYTL OS-EDDYEE OS-PARSONSCF OS-GERBERDA OS-GIVENSDL OS-SMITHPW1 OS-WICKHAMYD OS-RYANSP1A OS-ARMORBS OS-BAILESMD OS-PIERCELR OS-SHEPPARDRO OS-FUCHSSL OS-SICKLESTS OS-LEFEBVRESA OS-RIPPETOK OS-WATSON MP1 OS-PARSONSDOH OS-COLLINSRL2 OS-DAUGHERTYD OS-MCGEET OS-MAYLEVJ OS-WINDLANDB OS-HUMEJD OS-SHETLERF OS-CURREYLM OS-FRANSICCM OS-WILLIAMSG OS-STAHLPR4 OS-STAHLPR4-2 OS-STAHLPR3 OS-MATH ENYB Sample Date 3/20/2002 3/21/2002 3/21/2002 3/21/2002 3/21/2002 3/21/2002 3/21/2002 3/22/2002 3/22/2002 3/22/2002 4/1/2002 4/1/2002 4/1/2002 4/1/2002 4/3/2002 4/8/2002 4/17/2002 5/22/2002 3/20/2002 3/20/2002 3/21/2002 3/22/2002 4/15/2002 4/15/2002 4/17/2002 5/22/2002 4/9/2002 4/11/2002 4/16/2002 4/18/2002 4/23/2002 5/1/2002 5/1/2002 5/1/2002 5/2/2002 5/2/2002 5/3/2002 5/3/2002 5/6/2002 5/6/2002 5/6/2002 5/15/2002 5/15/2002 5/15/2002 5/15/2002 C-8 ug/L ND (<0.010) 0.303 0.286 3.91 0.0962 0.203 NQ (<0.050) 0.224 0.239 0.802 0.237 ND (<0.010) 0.0805 0.195 6.4 8.59 0.102 0.416 1.35 0.0842 0.278 0.875 1.24 3.8 ND (<0.010) 0.955 12.1 12.9 4.49 17.2 2.09 0.104 16.9 0.0761 1.11 11.5 2.35 0.161 ND (<0.010) 16.7 1.35 6.35 6.36 11.1 0.582 Water Use* Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Sample Type Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well 1/30/2003 1 of 2 Tab 3.5 Consent Order T&F.xIs 000094 60000 Vs*o 'v i ; (V) < yo\J G W ipf -f -L<3cv Table 3.5 Summary of C-8 Analytical Results in Groundwater and Surface Water Ohio One-mile Radius Residential Sampling 1-Mile Sample ID OS-THOMPSONAM OS-ARBAUGHJ OS-YATESL OS-SPICERRF OS-STAHLPR2 OS-STEPHANML2 OS-RAUCH SPG1 RAUCH SPG2 OS-RAUCH SPG3 OS-RAUCH SPG4 OS-RAUCH SPG5 OS-WATSON MP2 OS-WATSON MP3 OS-SWEARINGENW OS-STAHLPR1 OS-CASTOB1 OS-CASTOB1-2 OS-CASTOB2 (dup) OS-CASTOB3 OS-STEPHANML OS-FARLEYED OS-WATSON MP4 OS-BEECHJB OS-BARICKMANCH OS-STEPHANML3 Sample Dale 5/16/2002 5/23/2002 5/24/2002 4/15/2002 4/8/2002 4/9/2002 4/11/2002 4/11/2002 4/11/2002 4/11/2002 4/11/2002 4/18/2002 4/18/2002 4/22/2002 4/8/2002 6/7/2002 6/7/2002 6/7/2002 6/7/2002 4/9/2002 4/15/2002 4/18/2002 5/29/2002 6/4/2002 4/9/2002 C-8 ug/L 4.22 1.02 3.28 1.29 5.72 8.88 3.58 4.67 4.4 4.97 5.76 18.1 23.6 8.55 4.97 3.81 4.3 2.96 5.83 5.41 1.26 7.33 2.85 0.748 2.52 Water Use* Unused Unused Unused Drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Non-drinking Water Unused Non-drinking Water Non-drinking Water Sample Type Well Well Well Spring Spring Spring Spring Spring Spring Spring Spring Spring Spring Spring Spring Spring Spring Spring Spring Cistern Cistern Cistern Cistern Cistern POOL * Drinking Water (highlighted in bold blue) indicates human consumption. Non-drinking Water uses include livestock watering, gardening and any other non-human consumption water uses. ND = Not Detected at or above the limit of detection (LOD). The listed LOD is approximate and varies by instrument and over time. NQ = Not Quantifiable. Detected at a concentration above the LOD and below the limit of quantification (LOQ). 1/30/2003 2 of 2 Tab 3.5 Consent Order T&F.xIs 000096 y 'o o u lo-OA-S 000097 Table 3.6 Summary of Off-site Sampling Program (C-8 Sampling) Ohio Two-mile Radius Residential Sampling DuPont Washington Works RESIDENTIAL SAMPLING FOR OHIO 2-MILE RADIUS (</D) E Number of homes contacted (1) 1131 o X Number of homes surveyed (1) 733 Number of wells identified (2) 123 JS "o Number of wells in survey sampled (2) 58 $ Number of wells sampled that are used for drinking water 49 ioVcmm) <0 Number of cisterns identified (2) Number of cisterns sampled (2> Number of cisterns sampled that are used for drinking water 7 3 0 Ocn) Number of springs identified <2) 3 c Number of springs sampled <2) 1 Q. CO Number of springs sampled that are used for drinking water 0 <o/) Total number of samples 62 E(0 CO Total number of collected samples used for drinking water 49 Note: Field duplicates not considered in sample count. <1) During this investigation, homeowners/residents identified within the sampling radius were contacted to determine residential water usage. Up to two contacts were attempted at each residence. After the second contact attempt, a voluntary survey was left at the residence. Because not all homeowners/residences to the survey, the number of residences surveyed is less than the number of homes contacted. (2)Some water sources (e.g. wells, cisterns, springs) identified during the survey were not sampied. In many cases, sampling of these water sources was refused by the homeowners/residents. In other cases, the water sources were either not accessible or damaged. As a consequence, the number of water sources sampled was less than the number of water sources identified. 2/4/2003 1 of 1 Tab 3.6 Consent Order T&F.xIs 000038 Zone A B C 1/30/2003 Table 3.7 Summary of C-8 Analytical Results Zones A, B and C Ohio Two-Mile Radius C-8 Residential Sampling Sample ID OS-AnkromCA OS-BedilionWW OS-BoringAE OS-CantleyWA OS-CollinsNJ OS-HarrahGC OS-HolcombB OS-KnottsC OS-LittleJM OS-McLaughlinJL OS-PhillipsPJ OS-WaltonDM OS'-WhiteAL OS-BoardJG OS-BosoFE OS-BuchananAF OS-FlemingWV OS-GrimRR OS-KidderEM OS-McKownFL OS-MercerVE OS-MerinarJL OS-SmithDD OS-SmithWW OS-SordenD OS-StarkeyRR OS-ThomasJB OS-WelchJD OS-WellsB OS-WilliamsH OS-WilsonRM1 OS-WilsonRM2 OS-FrameRD OS-SamsJR OS-SpiresRA O S -turiczekJM OS-AdamsGL OS-BowersockVK OS-CastoHE OS-CookJM OS-DavisJH OS-FosterTV OS-HigginsJL OS-JacobsDK OS-KautzCR OS-KempN OS-KetelsonD Sample Date 7/9/2002 7/1/2002 6/26/2002 7/19/2002 7/9/2002 6/26/2002 7/25/2002 9/10/2002 7/9/2002 7/24/2002 7/2/2002 6/26/2002 7/8/2002 8/6/2002 7/25/2002 7/25/2002 8/22/2002 7/30/2002 9/17/2002 7/24/2002 7/24/2002 9/23/2002 7/31/2002 9/12/2002 9/10/2002 7/25/2002 9/19/2002 9/10/2002 9/17/2002 9/30/2002 7/31/2002 7/31/2002 7/24/2002 8/8/2002 8/8/2002 9/5/2002 8/22/2002 8/14/2002 8/16/2002 8/14/2002 9/11/2002 8/14/2002 8/15/2002 8/16/2002 8/22/2002 9/11/2002 9/11/2002 C-8 ug/L Water Use* 0.059 Drinking Water 1.710 Drinking Water 1.150 Drinking Water 1.490 Drinking Water 0.281 Drinking Water 0.844 Drinking Water NQ (<0.05) Drinking Water 2.590 Drinking Water 2.130 Drinking Water 0.064 Drinking Water 2.240 Drinking Water 0.413 Drinking Water , 3.960 Drinking Water 6.500 Drinking Water 0.290 Drinking Water 0.755 Drinking Water NQ (<0.05) Drinking Water 0.501 Drinking Water 4.150 Non-drinking Water 0.973 Non-drinking Water 0.784 Drinking Water 0.943 Drinking Water 1.810 Drinking Water 3.030 Unused 0.289 Drinking Water 0.164 Non-drinking Water 6.380 Non-drinking Water 6.850 Non-drinking Water 7.290 Unused 8.680 Unused 2.040 Drinking Water 4.750 Non-drinking Water 3.020 Non-drinking Water 0.592 Non-drinking Water 0.217 Non-drinking Water 0.374 Non-drinking Water 0.205 Drinking Water 0.083 Drinking Water 0.092 Drinking Water ND (<0.01) Drinking Water ND (<0.01) Drinking Water 0.812 Drinking Water ND (<0.01) Drinking Water ND (<0.01) Drinking Water ND (<0.01) Drinking Water 0.091 Drinking Water 0.092 Drinking Water Sample Type Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Spring Cistern Cistern Cistern Well Well Well Well Well Well Well Well Well Well Well 1 of 2 Tab 3.7 Consent Order T&F.xIs 000039 Table 3.7 Summary of C-8 Analytical Results Zones A, B and C Ohio Two-Mile Radius C-8 Residential Sampling Zone C (cont.) Sample ID OS-KingCD OS-KingCD-2 (DUP) OS-KirkWE OS-KnoxGT OS-MillironMP OS-MoodyDA OS-ShivelyJH OS-SouthallSA OS-SpaderJD OS-St. Clair OS-StimpertFE OS-TaittWJ OS-Transport OS-WebbD OS-WheatonCA OS-WheatonDL Sample Date 8/16/2002 8/16/2002 8/14/2002 8/16/2002 8/21/2002 8/20/2002 8/22/2002 8/22/2002 8/16/2002 9/25/2002 8/21/2002 9/9/2002 8/16/2002 9/25/2002 8/24/2002 8/21/2002 C-8 ug/L ND (<0.01 ) ND (<0.01 ) ND (<0.01 ) ND (<0.01 ) ND (<0.01 ) ND (<0.01 ) NQ (<0.05) 0.085 ND (<0.01 ) NQ (<0.05) ND (<0.01 ) 5.610 ND (<0.01 ) 0.128 NQ (<0.05) 0.087 Water Use* Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking W ater Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Sample Type Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well * Drinking W ater (highlighted in bold blue) indicates human consumption. Non-drinking Water uses include livestock watering, gardening and any other non-human consumption water uses. ND = Not Detected at or above the limit of detection (LOD). The listed LOD is approximate and varies by instrument and over time. NQ = Not Quantifiable. Detected at a concentration above the LOD and below the limit of quantification (LOQ). 1/30/2003 2 of 2 Tab 3.7 Consent Order T&F.xIs O O O IO O Table 3.8 Monitoring Wei) Construction and Groundwater Elevation Data DuPont Washington Works Facility Washington, WV New Well ID Old Well ID Measuring Point Elevation (ft) Total Depth (ft) Well Diameter (inches) Slot Size (inches) Monitoring Wells AE11-MW01 AJ06-MW02 AM07-PW01 AO08-PW01 AX13-PW01 D08-MW01 E13-MW01 TW-74 336 331 335 TW-M5 TW-76 628.94 69.29 2 0.010 635.55 128 2 0.010 634.26 96 18 632.91 95 18 630.69 90 18 600.67 4 625.47 76.8 2 0.010 ' *- -, K16-PW01 L04-PW01 L4(354) GALLERY 623.24 589.75 18 Screen Length (ft) Elevation o f Screen Interval (ft) 10 569.65 559.65 15 522.55 507.55 20 20 13 558.26 538.26 557.91 537.91 553.69 540.69 Groundwater Elevation (feet) January-02 567.02 -- * February-02 March-02 April-02 May-02 August-02 566.02 564.20 565.93 566.54 567.61 -- -- -- -- -- * * * * * October-02 568.52 569.55 * ` Groundwater elevations not measured in production wells. " Well was dry * * * * * -- * * * * * * 562.73 562.69 562.09 562.51 562.71 564.55 564.24 10 558.67 548.67 561.29 561.12 562.04 560.59 560.76 562.23 561.91 * * * * * * * NA * * * * * TOTOOO 1/30/2003 1 of 2 T-*u o o r*. .Af~\__ Table 3.8 Monitoring Weil Construction and Groundwater Elevation Data DuPont Washington Works Facility Washington, WV New Well ID Old Well ID Measuring Point Elevation (ft) Total Depth (ft) Well Diameter (inches) Slot Size (inches) Monitoring Wells N04-MW03 N13-MW01 P04-MW02 P08-MW01 Q04-MW02 R04-MW02 V05-PW01 Y14-MW01 Y14-MW02 Ron's MW-5 TW-83 Ron's MW-4 Ron's MW-1 TW-85 RANNEY TW-90 595.44 88.5 2 10 625.87 59.95 2 0.010 592.39 27.81 2 0.010 629.29 68.3 2 598.76 39.64 2 594.92 27.64 2 0.010 632.00 92 NA 642.25 90 2 0.010 643.12 131.59 2 0.010 Screen Length (ft) Elevation of Screen Interval (ft) 15 521.94506.94 5 570.92 565.92 10 574.58 564.58 January-02 -- -- 572.35 February-02 March-02 -- 559.92 571.91 -- ** 573.35 April-02 -- * * 573.13 May-02 -- ** 574.32 August-02 -- ** 572.69 October-02 567.82 ** 572.11 ` Groundwater elevations not measured in production wells. "W e ll was dry 5 10 10 565.99 560.99 569.12559.12 577.28 567.28 Groundwater Elevation -- 560.10 ** ** ** 562.09 560.88 560.05 559.45 560.40 559.77 563.77 563.06 576.61 576.39 577.36 576.97 577.10 575.28 574.98 1 542.00 541.00 * * * * * * * 10 562.25 552.25 562.78 562.15 561.39 561.34 561.67 563.05 562.89 15 526.53 511.53 -- -- -- -- -- -- 561.75 00102 1/30/2003 2 of 2 T#-.k 1 O t o r- 1/29/2003 Table 3.9 Summary of Analytical Results: C-8 in Groundwater DuPont Washington Works Facility Washington, WV Sample AE11-MW01 AJ06-MW02 AM07-PW01 A008-PW01 AX13-PW01 Date 10/16/2002 9/4/2002 5/23/2002 4/29/2002 3/26/2002 2/22/2002 1/28/2002 2/2/1999 11/10/1998 10/16/2002 10/22/2002 8/26/2002 5/17/2002 4/16/2002 3/21/2002 2/14/2002 1/22/2002 11/20/2000 8/16/2000 5/12/1999 2/3/1999 11/18/1998 6/19/1998 6/2/1997 4/2/1996 10/22/2002 8/26/2002 5/17/2002 4/16/2002 3/21/2002 2/14/2002 1/22/2002 11/20/2000 11/20/00 (dup) 8/15/2000 5/12/1999 6/19/1998 6/2/1997 4/2/1996 10/22/2002 8/26/2002 5/17/2002 4/16/2002 3/21/2002 2/14/2002 C-8 (ug/l) 1.74 1.92 1.25 1.22 2.82 1.45 1.20 0.69 L 0.41 0.133 0.269 0.335 0.247 0.159 0.171 0.129 0.131 0.24 0.071 J 0.578 0.082 B 1.9 L 0.4 0.79 0.48 0.415 0.42 0.499 0.497 0.568 0.439 0.355 0.4 0.26 0.167 0.307 1 0.55 0.52 0.721 0.834 0.911 1.42 1.22 1.03 000103 1 of 4 Tab 3.9 Consent Order T&F.xIs 1/29/2003 Table 3.9 Summary of Analytical Results: C-8 in Groundwater DuPont Washington Works Facility Washington, WV Sample D08-MW01 E13-MW01 K16-PW01 L04-PW01 N04-MW01 N04-MW03 Date 10/16/2002 9/4/2002 5/23/2002 4/29/2002 3/26/2002 2/22/2002 1/28/2002 10/16/2002 9/4/2002 5/23/2002 4/29/2002 3/28/2002 2/22/2002 1/28/2002 5/12/1999 2/2/1999 11/11/1998 10/22/2002 8/26/2002 5/17/2002 4/16/2002 3/21/2002 2/14/2002 1/22/2002 11/20/2000 2/9/1999 11/18/1998 10/25/2002 8/13/2002 5/21/2002 4/18/2002 3/21/2002 2/7/2002 1/15/2002 7/11/2001 4/11/2001 11/20/2000 2/7/1999 11/18/1998 11/18/98 (dup) 1/28/2002 10/16/2002 C-8(ug/l) 0.126 0.117 0.551 0.424 0.262 1.27 0.582 3.43 2.39 2.47 2.44 1.62 2.32 2.11 0.882 0.59 L 2 16.2 9.71 12.4 13.2 17.2 12 10.5 7.5 16.2 0.46 L 14.3 3.06 15.1 16.1 40.9 23.5 30.9 0.202 3.99 13.8 5.89 7.9 J 3.9 J 689 21.2 2 of 4 00104 Tab 3.9 Consent Order T&F.xIs 1/29/2003 Table 3.9 Summary of Analytical Results: C-8 in Groundwater DuPont Washington Works Facility Washington, WV Sample N13-MW01 P04-MW02 P08-MW01 Q04-MW02 R04-MW02 Date 10/16/2002 9/4/2002 5/23/2002 4/29/2002 3/28/2002 2/25/2002 2/2/1999 11/11/1998 10/16/2002 10/16/02 (dup) 9/4/2002 5/23/2002 4/29/2002 3/26/2002 2/25/2002 1/28/2002 1/25/2001 2/6/1999 11/12/1998 10/16/2002 9/4/2002 5/23/2002 4/29/2002 3/28/2002 2/25/2002 2/4/1999 11/13/1998 10/16/2002 9/4/2002 5/23/2002 4/29/2002 3/26/2002 2/25/2002 1/28/2002 2/4/1999 11/13/1998 10/16/2002 9/4/2002 5/23/2002 4/29/2002 3/26/2002 2/25/2002 1/28/2002 1/25/2001 2/6/1999 11/12/1998 C-8 (ug/i) Dry-no sample Dry-no sample Dry-no sample Dry-no sample Dry-no sample 57.8 29.6L <0.1 46600 48300 34400 42400 36500 32300 26800 23600 12600 13600 8300 120 Dry-no sample Dry-no sample Dry-no sample Pump problems-no sample 20.7 43.4 36 7720 32.2 1480 1210 2070 1590 1480 994 660 84100 66500 68100 56300 54400 43600 47500 13800 9420 1300 3 of 4 Tab 3.9 Consent Order T&F.xIs 000105 Table 3.9 Summary of Analytical Results: C-8 in Groundwater DuPont Washington Works Facility Washington, WV Sample V05-PW01 Y14-MW01 Y14-MW02 West Well Field (1) Date 10/25/2002 8/13/2002 5/21/2002 4/18/2002 3/21/2002 2/7/2002 1/15/2002 7/11/2001 4/11/2001 11/20/2000 2/7/1999 2/7/99 (dup) 11/18/1998 10/16/2002 9/4/2002 5/23/2002 4/29/2002 3/28/2002 2/22/2002 1/28/2002 2/2/1999 11/10/1998 10/16/2002 10/25/2002 8/13/2002 5/21/2002 4/16/2002 3/21/2002 2/7/2002 1/15/2002 7/11/2001 4/11/2001 C-8(uq/I) 51.2 34.8 35.8 37.6 40.9 25.1 29 11.4 5.48 13.7 12.4 3.95 0.66 L 18.2 18.4 15.3 13.9 15.5 10.9 12.7 4.95 L 12 NQ (< 0.05) 10.3 6.41 7.09 6.69 7.72 5.77 6.52 2.31 1.58 J = estimated value (below laboratory quantification limit) L = possible low bias result (relative to QA/QC) B= compound detected in QC blank Note: Analytical method changed as of November 2001 (see Section 2.0 of DuPont (2003b) for details). 1/29/2003 4 of 4 Tab 3.9 Consent Order T&F.xIs 001Q6 ,,J 1/29/2003 Table 3.10 Summary of Analytical Results: C-8 in Surface Water DuPont Washington Works Facility Washington, WV Sample OUTLET 001 OUTFALL 002 OUTLET 003 Date 11/13/2002 10/18/2002 9/24/2002 8/27/2002 7/23/2002 6/25/2002 5/20/2002 4/16/2002 3/19/2002 2/5/2002 1/17/2002 12/20/2001 11/13/2002 11/13/02 (dup) 10/18/2002 9/24/2002 8/27/2002 8/27/02 (dup) 7/23/2002 6/25/2002 6/25/02 (dup) 5/20/2002 4/16/2002 3/19/2002 2/5/2002 1/17/2002 12/20/2001 11/26/01* 10/25/2001 9/19/2001 7/11/2001 6/14/2001 5/31/2001 4/11/2001 3/21/2001 2/14/2001 11/13/2002 10/18/2002 9/24/2002 8/27/2002 7/23/2002 6/25/2002 5/20/2002 4/16/2002 3/19/2002 3/19/02 (dup) 2/5/2002 c-8(ua/i> 17.0 10.5 2.15 2.94 8.63 17.9 22.4 19.7 21.4 9.43 10.9 3.72 4.75 5.28 3.49 2.14 2.56 2.51 2.29 3.86 3.81 4.13 2.45 5.85 4.66 4.23 1.98 4.84 2.8 0.118 0.558 0.594 0.436 1.5 8.54 1.74 1.24 0.87 0.317 0.268 0.291 0.175 0.503 2.76 2.91 2.81 1.33 1 of 3 000107 Tab 3.10 Consent Order T&F.xIs 1/29/2003 Table 3.10 Summary of Analytical Results: C-8 in Surface Water DuPont Washington Works Facility Washington, WV Sample OUTLET 003 (Cont.) OUTFALL 005 OUTLET 007 OUTLET 105 Date 1/17/2002 1/17/02 (dup) 12/20/2001 11/13/2002 10/18/2002 9/24/2002 9/24/02 (dup) 8/27/2002 7/23/2002 6/25/2002 5/20/2002 5/17/2002 4/16/2002 3/19/2002 2/5/2002 1/17/2002 12/20/2001 12/20/01 (dup) 11/26/2001 10/25/2001 9/19/2001 8/30/2001 7/11/2001 6/14/2001 5/31/2001 4/11/2001 3/21/2001 2/14/2001 11/13/2002 10/18/2002 10/18/02 (dup) 9/24/2002 8/27/2002 7/23/2002 7/23/02 (dup) 6/25/2002 5/20/2002 4/16/2002 3/19/2002 2/5/2002 2/5/02(dup) 1/17/2002 12/20/2001 11/13/2002 10/18/2002 9/24/2002 8/27/2002 7/23/2002 CJXugfl) 0.956 3.99 0.713 18.1 12.1 4.64 5.02 12.4 19.2 17.9 98.6 65.7 3.8 9.26 141 137 31.4 35.2 915 65.7 2.86 2.16 120 7.4 1.43 4.31 199 153 8.56 0.251 0.209 NQ (<0.05) 0.207 0.597 0.544 0.284 0.49 0.567 0.483 0.32 0.339 0.871 1.99 10.5 54.6 3.69 6.73 34.7 I 000108 2 of 3 Tab 3.10 Consent Order T&F.xIs Table 3.10 Summary of Analytical Results: C-8 in Surface Water DuPont Washington Works Facility Washington, WV Sample Date C-8<ug/l) OUTLET 105 (Cont.) 6/25/2002 5/20/2002 5/20/02 (dup) 4/16/2002 3/19/2002 2/5/2002 1/17/2002 12/20/2001 3.86 6.27 5.16 15.9 13.2 14.6 7.53 9.78 Note: Analytical method changed as of November 2001 (see Section 2.0 o f DuPont (2003b) for details). 1/29/2003 3 of 3 00103 Tab 3.10 Consent Order T&F.xIs OTTOOO R iv e r W a te r in v e s tig a tio n * Washington Works Facility 1/29/2003 Table 3.11 Ohio River Water Sampling C-8 Results DuPont Washington Works Facility and Letart Landfill Upstream Near Facility Downstream T ra n s e c t L o c a tio n D e s c rip tio n 26 Miles Upstream of the Washington Works Facility 10 Miles Upstream of the Washington Works Facility Upstream of the Washington Works Facility - eastern end of Blennerhassett Island Along Washington Works Facility - North of Outfall 001 Along Washington Works Facility - East of Outfall 007 Along Washington Works Facility Downstream of Outfall 005 1.5 Miles Downstream of the Washington Works Facility 3 Miles Downstream of the Washington Works Facility 10 Miles Downstream of the Washington Works Facility 18 Miles Downstream of the Washington Works Facility N um ber o f S a m p lin g P o in ts 3 3 3 2 1 1 1 T o ta l S a m p le N um ber of D e p th s S a m p le s Dip and Mid column 2 T ra n se ct N um ber Dip and Mid column Dip, Mid column and Bottom Dip, Mid column and Bottom 2 3 9 Dip, Mid column and Bottom 9 +1 (Dup) 2 2 3 3 3 4 4 4 4 4 4 4 4 4 5 5 5 5 Dip, Mid column and Bottom 9 5 5 5 5 5 5 6 6 6 6 6 6 6 Dip, Mid 6 +1 (Dup) column and Bottom Dip and Mid column Dip and Midcolumn Dip and Mid column 2 2 2 6 6 7 7 7 7 7 7 7 8 8 9 9 10 10 L o c a tio n on T ra n sa ct S a m p le Type center center center mid-column dip mid-column center center dip bottom center mid-column center WV-side WV-side WV-side center center center OH-side dip bottom mid-column dip bottom mid-column dip bottom OH-side OH-side WV-side mid-column dip bottom WV-side WV-side center mid-column dip bottom center center OH-side OH-side OH-side OH-side WV-side mid-column dip bottom mid-column dip dip bottom WV-side WV-side center center center OH-side mid-column dip bottom mid-column dip bottom OH-side OH-side WV-side WV-side WV-side WV-side center center center center center center center center center mid-column dip bottom mid-column dip dip bottom mid-column dip mid-column dip mid-column dip mid-column dip 1 of 2 S a m p le ID WWK-R-TS 1-2M WWK-R-TS 1-2S WWK-R-TS 2-2M WWK-R-TS 2-2S WWK-R-TS 3-2B WWK-R-TS 3-2M WWK-R-TS 3-2S WWK-R-TS 4-1B WWK-R-TS 4-1M WWK-R-TS 4-1S WWK-R-TS 4-2B WWK-R-TS 4-2M WWK-R-TS 4-2S WWK-R-TS 4-3B WWK-R-TS 4-3M WWK-R-TS 4-3S WWK-R-TS 5-1B WWK-R-TS 5-1M WWK-R-TS 5-1S WWK-R-TS 5-2B WWK-R-TS 5-2M WWK-R-TS 5-2S WWK-R-TS 5-3B WWK-R-TS 5-3M WWK-R-TS 5-3S WWK-R-TS 5-3S-2 (DUP) WWK-R-TS 6-1B WWK-R-TS 6-1M WWK-R-TS 6-1S WWK-R-TS 6-2B WWK-R-TS 6-2M WWK-R-TS 6-2S WWK-R-TS 6-3B WWK-R-TS 6-3M WWK-R-TS 6-3S WWK-R-TS 7-1B WWK-R-TS 7-1M WWK-R-TS 7-1S WWK-R-TS 7-1S-2 (DUP) WWK-R-TS 7-2B WWK-R-TS 7-2M* WWK-R-TS 7-2S* WWK-R-TS 8-2M WWK-R-TS 8-2S WWK-R-TS 9-2M WWK-R-TS 9-2S WWK-R-TS 10-2M WWK-R-TS 10-2S o' O oo o' d O ZZ C -8 u g fL ND (<0.010) ND (<0.010) ND (<0.010) NQ (<0.050) ND (<0.010) ND (<0.010) ND (<0.010) ND {<0.010) ND (<0.010) ND (<0.010) ND (<0.010) ND (<0.010) ND (<0.010) ND (<0.010) ND (<0.010) ND (<0.010) ND (<0.010) NQ (0 .0 5 0 ) ND (0 .010 ) ND (0 .0 1 0 ) ND (0.010 ) ND (0.010) ND (0 .0 1 0 ) ND (0 ,0 1 0 ) ND (0 .0 1 0 ) ND (0 .0 1 0 ) ND (0 .0 1 0 ) ND (0 .010 ) ND (0 .010 ) ND (0 .010 ) NQ (0 .0 5 0 ) ND (0 .010 ) ND (0 .010 ) 0.113 0.131 0.113 0.138 0.123 0.0949 0.104 0.999 1.09 0.292 0.298 0.236 0.239 - D ate 6/25/2002 6/25/2002 6/26/2002 6/26/2002 10/17/2002 6/26/2002I 6/26/2002 6/28/2002 6/28/2002 6/28/2002 6/28/2002 6/28/2002 6/26/2002 6/28/2002 6/28/2002 6/28/2002 6/27/2002 6/27/2002 6/27/2002 6/27/2002 6/27/2002 6/27/2003 6/27/2002 6/27/2002 6/27/2003 6/27/2003 6/27/2002 6/27/2002 6/27/2002 6/27/2002 6/27/2002 6/27/2002 6/27/2002 6/27/2002 6/27/2002 10/17/3)02 10/17/2002 10/17/2002 10/17/2002 10/17/2002 10/17/2002 10/17/2002 7/10/2002 7/10/2002 7/10/2002 7/ 10/2002 7/ 10/2002 7/ 10/2002 Tab 3.11 Consent Order T&F.xis Table 3.11 Ohio River Water Sampling C-8 Results DuPont Washington Works Facility and Letart Landfill R iv e r W a te r In v e s tlg a tio n a Letart Landfill Near Landfill Downstream i 1 2 Adjacent to the Letart Landfill Downstream of the Letart Landfill dum berof S a m p lin g P o in ts 1 1 "T o ta l S a m p le N um ber of D e p th s S a m p le s Dip and Mid 2 column Dip and Mid 2 +1 (Dup) column * C-8 WWK-R-TS7-2M and WWK-R-TS7-2S were also sampled on 7/10/02. C-8 concentrations were 0.134 and 0.0984, respectively. T ra n sect N um ber 11 11 12 12 12 L o c a tio n on T ra n se ct WV-side WV-slde WV-slde WV-side WV-side S a m p le Type mid-column dip mid-column dip dip S a m o le ID WWK-R-TS 11-1M WWK-R-TS 11-1S 12WWK-R-TS -1M 12WWK-R-TS -1S WWK-R-TS 12-1S-2 (DUP C - 4 u o / L : * ' " D a t e # * 0.109 7/11/2002 0.101 7/11/2002 0.0971 0.118 0.128 7/11/2002 7/11/2002 7/11/2002 TTTOOO 1/29/2003 2of 2 Tab 3.11 Consent Order T&F.xIs Table 3.12 Outfall 005 C-8 concentration (ug/l) DuPont Washington Works Sample ID WWK-Z- OUTFALL 005 WWK-Z- OUTFALL 005 WWK-Z- OUTFALL 005 VWVK-Z- OUTFALL 005 WWK-Z- OUTFALL 005 WWK-Z- OUTFALL 005 WWK-Z- OUTFALL 005 WWK-Z- OUTFALL 005 WWK-Z- OUTFALL 005 WWK-Z- OUTFALL 005 Date 6/24/2002 6/25/2002 6/26/2002 6/27/2002 7/1/2002 7/10/2002 7/11/2002 7/12/2002 10/16/2002 10/17/2002 C-8 ug/L 26.7 17.9 47.7 79.3 13.6 37.8 239.0 12.5 141.0 18.0 1/29/2003 1 of 1 Tab 3.12 Consent Order T&F.xIs 000112 Table 3.13 Summary of C-8 in Groundwater Public Water Supplies, West Virginia and Ohio Dupont Washington Works Facility, Washington WV L o c a tio n Parkersburg, WV Belpre, OH Blennerhassett Island, WV Little Hocking, OH 1/29/2003 S a m p le ID PPSDPT PPSDAT PPSDAT PPSDRANY1 PPSDRANY1 PPSDRANY1 PPSDRANY2 PPSDRANY3 PPSDRANY4 PPSDRANY5 BELPSDAT BELPSDAT BELPSDAT BELPSDPW1 BELPSDPW1 BELPSDPW2 BELPSDPW2 BELPS0PW2 BELPSDPW3 BELPSDPW3 BELPSDPW4 BELPSDPW4 BELPSDPW4 BELPSDPW5 BELPSDPW5 BELPSDPW5 BELPSDPW5 BLENI TWO BLENI TW7 BLENI W19A BLENISLEPS1 LHPSD1 LHPSD1 LHPSD1 LHPSD1 LHPSD1 LHPSD1 LHPSD1 LHPSD2 LHPSD2 LHPSD2 LHPSD2 LHPSD2 LHPSD2 LHPSD2 LHPSD2 LHPSD2 LHPSD3 LHPSD3 S a m p la D a ta 3/6/2002 3/6/2002 4/25/2002 3/6/2002 3/6/2002 4/25/2002 3/6/2002 3/6/2002 3/6/2002 3/6/2002 2/7/2002 3/25/2002 4/23/2002 2/7/2002 3/25/2002 2/7/2002 2/7/2002 3/25/2002 3/25/2002 4/23/2002 2/7/2002 3/25/2002 4/23/2002 2/7/2002 3/25/2002 4/23/2002 4/23/2002 2/21/2002 2/21/2002 2/21/2002 1/30/2002 12/20/2001 1/21/2002 2/22/2002 3/26/2002 4/23/2002 8/21/2002 10/16/2002 12/20/2001 12/20/2001 1/21/2002 2/22/2002 2/22/2002 3/26/2002 4/23/2002 8/21/2002 10/16/2002 12/20/2001 1/21/2002 1 of 5 C -8 tig li NQ (cO.050) NQ (<0.050) NQ (<0.050) 0.0693 0.0686 0.0746 ND (<0.010) ND (<0.010) ND (<0.010) ND {<0.010) 0.0818 0.113 0.12 0.0995 0.13 NQ (<0.050) NQ {<0.050) NQ {<0.050) 0.141 0.12 0.101 0.133 0.114 0.107 0.103 0.107 0.111 ND (<0.010) NQ (<0.050) 0.316 0.165 1.82 1.72 2.37 2.99 2.02 3.65 3.41 3.72 3.52 2.97 2.03 2.07 3.31 3.4 4.26 3.98 0.844 0.744 C o m m e n ts Before Treatment Sample After Treatment Sample After Treatment Sample Production Well duplicate Production Well Production Well Production Well Production Well Production Well After Treatment Sample After Treatment Sample After Treatment Sample Production Well Production Well Production Well duplicate Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well duplicate Test well Test well Test well Drinking Supply Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well duplicate Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well 000113 Tab 3.13 Consent Order T&F.xIs Table 3.13 Summary of C-8 in Groundwater Public Water Supplies, West Virginia and Ohio Dupont Washington Works Facility, Washington WV L o c a tio n Little Hocking, OH (cont.) General Electric, WV Lubeck, WV I S a m p le ID LHPSD3 LHPSD3 LHPSD3 LHPSD3 LHPSD3 LHPSD3 LHPSD5 LHPSD5 LHPSD5 LHPSD5 LHPSD5 LHPSD5 LHPSD5 LHPSD5 LHPSDEP001 LHPSDEP001 LHPSDEP001 LHPSDEP001 LHPSDTW1 LHPSDTW1 LHPSDTW10 LHPSDTW10 LHPSDTW11 LHPSDTW11 LHPSDTW12 LHPSDTW12 LHPSDTW2 LHPSDTW2 LHPSDTW3 LHPSDTW3 LHPSDTW4 LHPSDTW4 LHPSDTW4 LHPSDTW4 LHPSDTW4 LHPSDTW5 LHPSDTW6 LHPSDTW6 LHPSDTW6 LHPSDTW9 LHPSDTW9 LHTORCHBS BARTLETTCC 339B STA GE WELL 3 GE WELL 3 GE WELL 3 GE WELL 3 LPSDAT LPSDAT S a m p le D a te 2/22/2002 3/26/2002 4/23/2002 8/21/2002 10/16/2002 10/16/2002 12/20/2001 1/21/2002 1/21/2002 2/22/2002 3/26/2002 4/23/2002 8/21/2002 10/16/2002 1/22/2002 3/26/2002 4/23/2002 10/16/2002 1/22/2002 8/21/2002 1/21/2002 8/21/2002 1/21/2002 8/21/2002 1/21/2002 8/21/2002 1/22/2002 8/21/2002 1/22/2002 8/21/2002 1/22/2002 3/26/2002 4/23/2002 8/21/2002 10/16/2002 8/21/2002 1/22/2002 8/21/2002 8/21/2002 1/22/2002 8/21/2002 1/22/2002 1/22/2002 1/22/2002 1/3/2002 1/3/2002 2/21/2002 4/26/2002 3/28/2002 4/26/2002 1/29/2003 2 of 5 C -8 u g fl 0.42 0.827 0.783 0.952 0.495 0.434 7.66 6.22 6.14 5.69 6.57 6.11 8.09 8.58 1.69 2.62 1.93 4.29 2.16 0.81 1.9 1.1 1.41 1.73 0.758 0.824 0.103 0.081 4.48 4.17 37.1 33.3 28.7 12.3 14.5 6.26 1.79 1.15 1.23 0.364 0.812 1.85 1.94 1.81 1.78 1.87 1.75 1.84 0.69 0.652 C o m m e n ts | Production Well Production Well Production Well Production Well Production Well duplicate Production Well Production Well duplicate Production Well Production Well Production Well Production Well Production Well Water System Point Water System Point Water System Point Water System Point Test well Test well Test well Test well Test well Test well Test well Test well Test well Test well Test well Test well Test well Test well Test well Test well Test well Test well Test well Test well duplicate Test well Test well Water System Point Water System Point Water System Point Production Well duplicate Production Well Production Well After Treatment Sample After Treatment Sample 000114 Tab 3.13 Consent Order T&F.xIs Table 3.13 Summary of C-8 in Groundwater Public Water Supplies, West Virginia and Ohio Dupont Washington Works Facility, Washington WV L o c a tio n Lubeck, WV (cont.) Belleville Hydra Plant, WV Tuppers Plains PSD, OH 'H ttr 1/29/2003 S a m p le ID LPSDAT LPSDAT LPSD WELL A LPSD WELL A LPSD WELL A LPSD WELL A LPSD WELL A LPSD WELL A LPSD WELL B LPSD WELL B LPSD WELL B LPSD WELL B LPSD WELL B LPSD WELL C LPSD WELL C LPSD WELL C LPSD WELL C LPSD WELL C LPSD WELL C LPSD WELL D LPSD WELL D LPSD WELL D LPSD WELL D LPSD WELL D LPSD WELL D LPSD WELL E LPSD WELL E LPSD WELL E LPSD WELL E LPSD WELL E LPSD WELL E LPSD WELL F LPSD WELL F LPSD WELL F LPSD WELL F LPSD WELL F LPSD WELL F LPSD WELL F LPSD WELL F BELLEVILLELD TPPSDPT TPPSDPT TPPSDPT TPPSDPT TPPSDAT TPPSDAT TPPSDAT TPPSDAT TPPSDAT TPPSDPW1 S a m p le D a te 6/24/2002 10/15/2002 1/3/2002 2/21/2002 3/28/2002 4/26/2002 7/24/2002 10/15/2002 2/21/2002 3/28/2002 4/26/2002 7/24/2002 10/15/2002 1/3/2002 2/21/2002 3/28/2002 4/26/2002 7/24/2002 10/15/2002 1/3/2002 2/21/2002 3/28/2002 4/26/2002 7/24/2002 10/15/2002 1/3/2002 2/21/2002 3/28/2002 4/26/2002 7/24/2002 10/15/2002 1/3/2002 2/21/2002 3/28/2002 3/28/2002 4/26/2002 7/24/2002 7/24/2002 10/15/2002 1/29/2002 2/6/2002 3/25/2002 7/23/2002 10/15/2002 2/6/2002 3/25/2002 4/24/2002 7/23/2002 10/15/2002 2/6/2002 3 of 5 C -8 u g /l 0.6 0.653 0.764 0.683 0.796 0.938 0.753 0.856 0.61 0.551 0.532 0.443 0.537 0.592 0.479 0.491 0.471 0.398 0.504 0.758 0.725 0.692 0.506 0.444 0.517 0.332 1 1.09 1.11 1.02 1.21 1.04 0.313 0.358 0.352 0.332 0.284 0.283 0.355 NQ (C0.050) 0.372 0.347 0.24 0.226 0.361 0.358 0.363 0.246 0.268 0.726 C o m m e n ta After Treatment Sample After Treatment Sample Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well duplicate Production Well Production Well duplicate Production Well Miscellaneous Use Before Treatment Sample Before Treatment Sample Before Treatment Sample Before Treatment Sample After Treatment Sample After Treatment Sample After Treatment Sample After Treatment Sample After Treatment Sample Production Well 00015 Tab 3.13 Consent Order T&F.xIs Table 3.13 Summary of C-8 in Groundwater Public Water Supplies, West Virginia and Ohio Dupont Washington Works Facility, Washington WV I L o c a tio n Tuppers Plains PSD, OH (cont.) Ravenswood Municipal, WV Mason County PSD, WV Racine Locks and Dam, WV Village of Racine, OH New Haven Water Dept., WV 1/29/2003 S a m p le ID TPPSDPW1 TPPSDPW1 TPPSDPW1 TPPSDPW1 TPPSDPW2 TPPSDPW2 TPPSDPW2 TPPSDPW2 TPPSDPW2 TPPSDPW3 TPPSDPW3 TPPSDPW3 TPPSDPW3 TPPSDPW4 TPPSDPW4 TPPSDPW4 TPPSDPW4 TPPSDPW5 TPPSDPW5 TPPSDPW5 TPPSDPW5 TPPSDPW6 TPPSDPW6 TPPSDPW6 TPPSDPW6 TPPSDPW6 COR ASIN COR ASOUT COR BLEND AT COR WELL 1 COR WELL 2 COR WELL3 COR WELL 4 COR WELL 5 MASONCPSD1 MASONCPSD1 MAS0NCPSD1 MASONCPSD2 MASONCPSD2 MASONCPSD2 MASONCPSD3 MASONCPSD3 MASONCPSD3 RACINELD VORAT VORRV3 VORWELL1 VORWELL2 NHPSDAT NHPSDPW1 S a m p le D a te 3/25/2002 4/24/2002 7/23/2002 10/15/2002 2/6/2002 3/25/2002 4/24/2002 7/23/2002 10/15/2002 2/6/2002 3/25/2002 7/23/2002 10/15/2002 2/6/2002 3/25/2002 7/23/2002 10/15/2002 2/6/2002 3/25/2002 7/23/2002 10/15/2002 2/6/2002 3/25/2002 4/24/2002 7/23/2002 10/15/2002 3/27/2002 3/27/2002 3/27/2002 3/27/2002 3/27/2002 3/27/2002 3/27/2002 3/27/2002 1/29/2002 3/27/2002 4/25/2002 1/29/2002 3/27/2002 4/25/2002 1/29/2002 3/27/2002 4/25/2002 1/4/2002 3/26/2002 3/26/2002 3/26/2002 3/26/2002 4/10/2002 4/10/2002 4 of 5 C -8 u g fl 0.705 0.702 0.588 0.486 0.417 0.327 0.371 0.235 0.255 NQ (<0.050) NQ (<Q.05Q) ND {<0.010) ND (<0.010) 0.0734 0.07 0.052 0.076 0.201 0.201 0.216 0.229 0.649 0.634 0.62 0.62 0.433 ND (<0.010) NQ (<0.050) ND (<0.010) ND (<0.010) ND (<0.010) ND (<0.010) ND (<0.010) ND (<0.010) NQ (<0.050) NQ (<0.050) NQ (<0.050) 0.0618 0.0838 0.0714 0.0707 0.102 0.063 0.518 ND (<0.010) ND (<0.010) ND (<0.010) ND (<0.010) ND (0.010) NQ (0.050) C o m m e n ts Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Air Stripper In Air Stripper Out Blend After Treatment Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Production Well Miscellaneous Use After Treatment Sample Production Well Production Well Production Well After Treatment Sample Production Well 000116 Tab 3.13 Consent Order T&F.xIs Table 3.13 Summary of C-8 in Groundwater Public Water Supplies, West Virginia and Ohio Dupont Washington Works Facility, Washington WV L o c a tio n ' New Haven Water Dept., WV Village of Syracuse, OH Village of Pomeroy, OH S a m p lo ID NHPSDPW1 VOSAT VOSAT VOS NORTH 2 VOS NORTH 2 VOS SOUTH R3 VOS SOUTH R3 VOPAT VOPAT VOPWELL1 VOPWELL2 VOPWELL2 VOPWELL4 VOPWELL4 S a m p le D a te 4/10/2002 3/29/2002 4/24/2002 3/29/2002 4/24/2002 3/26/2002 4/24/2002 3/26/2002 4/24/2002 4/24/2002 3/26/2002 4/24/2002 3/26/2002 4/24/2002 ND = Not Detected at or above the limit of detection (LOD). The listed LOD is approximate and varies by instrument and over time. NQ = Not Quantifiable. Detected at a level above the LOD and below the limit of quantification (LOQ). All C-8 results are reported in ug/l. Misc. = Miscellaneous water use is not used for drinking. C -8 u g fl NQ (<0.050) NQ (<0.050) ND (<0.010) NQ (<0.050) 0.491 0.208 ND (<0.010) 0.0659 0.0628 ND (0.010) 0.0689 ND (<0.010) 0.0851 0.0/12 C o m m e n ts duplicate After Treatment Sample After Treatment Sample Production Well Production Well Production Well Production Well After Treatment Sample After Treatment Sample Production Well Production Well Production Well Production Well Production Well ) 1/29/2003 5 of 5 000117 Tab 3.13 Consent Order T&F.xIs Table 3.14 Synoptic Groundwater Elevations February 2002 and Well Screen Locations DuPont Washington Works Facility Washington, West Virginia N e w ID M e a s u r in g P o in t E le v a tio n (fe e t)* O ld ID F e b ru a ry 2 0 0 2 D T W AC05-MW01 635.22 TW-E6 68.6 AL10-MW01 631.61 TW-M1 67.12 AOD8-MW01 636.02 TW-48 74.93 AO09-MW01 632.89 TW-26 70.32 AR09-MW01 635.27 TW-38 75.01 AX12-MW01 635.23 TW-39 73.81 D08-MW01 600.67 TW-M5 37.98 F06-MW01 601.14 TW-M6 38.9 I07-MW01 610.23 TW-M3 49.18 J08-MW01 630.21 TW-20 69.8 K14-MW01 627.34 TW-M4 68.25 L18-MW01 635.82 TW-27 78.87 M16-MW01 627.14 TW-55 68.9 N04-MW01 594.48 TW-32 16.46 N13-MW01 625.87 TW-54 65.95 P08-MW01 629.29 TW-53 69.19 Q04-MW02 598.76 TW-50 38.71 T13-MW01 632.69 TW-24 71.59 U05-MW02 631.17 TW-P12 79.02 U16-MW01 638.23 TW-25 76.5 V09-MW01 628.5 TW-3(pw-3) 67.38 V05-MW01 Z07-MW02 631.16 632.49 TW-E5 TW-22 67.48 67.9 AA04-MW01 599.95 TW-70 34.4 AA05-MW01 AB07-MW02 633.32 633.02 TW-71 TW-72 67.71 67.41 AE11-MW01 628.94 TW-74 62.92 E13-MW01 G17-MW01 625.47 632.81 TW-76 TW-77 64.35 73.35 M04-MW02 595.51 TW-79 13.42 M04-MW03 N04-MW02 N05-MW01 P04-MW02 P05-MW02 R04-MW02 S05-MW02 U04-MW01 V06-MW01 595.43 595.82 633.17 592.39 631.24 594.92 630.64 595.43 629.49 TW-80 TW-81 TW-82 TW-83 TW-84 TW-85 TW-86 TW-87 TW-88 13.93 13.78 73.18 20.48 71.14 18.53 71.66 11.97 70.53 W05-MW01 Y14-MW01 Z06-MW02 Z07-MW01 Z09-MW01 629.9 642.25 629.21 632.98 624.65 TW-89 TW-90 TW-91 TW-92 TW-93 70.42 80.1 65.2 68.97 60.95 * All Measuring Point Elevation data is from Vernon surveys in 1989 or 1998. F e b ru a ry 2 002 G ro u n d w a te r E le v a tio n (fe e t) 566.62 564.49 561.09 562.57 560.26 561.42 562.69 562.24 561.05 560.41 559.09 556.95 558.24 578.02 559.92 560.1 560.05 561.1 552.15 561.73 561.12 563.68 564.59 565.55 565.61 565.61 566.02 561.12 559.46 582.09 581.5 582.04 559.99 571.91 560.1 576.39 558.98 583.46 558.96 559.48 562.15 564.01 564.01 563.7 S c r e e n L o c a tio n s site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer perched water table site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer perched water table perched water table perched water table site primary aquifer perched water table site primary aquifer perched water table site primary aquifer perched water table site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer site primary aquifer 1/29/2003 lo fi Tab 3.14 Consent Order T&F.xIs noons Table 3.15 Summary of On-site and Off-site Exposure Pathways Evaluation DuPont Washington Works Facility On-Site C-8 Impacted Media SWMUs/Land filled Materials Soil Surface Water Groundwater Drinking water (from groundwater) Process water (from groundwater) Exposure Pathways Evaluation Exposure Pathways fo r Human Receptors Pathway Assessment [Complete (C) or Incomplete (1)] 1 1 1 1 C C Comparison to Screening C rite ria * -- -- 1.9(1) ug/l 150 ug/l 51.2 ug/i <150 ug/l Exposure Pathway/s fo r Ecological Receptors Pathway Assessment (Complete or Comparison to Screening Incom plete) I I I C riteria* -- .. -- I NA NA O ff-S ite C-8 Impacted Media Drinking Water (wells, springs and/or cisterns) - WV Non-drinking water (wells, springs and/or cisterns) - WV Unused water sources - WV Drinking Water (wells, springs and/or cisterns) - OH Non-drinking water (wells, springs and/or cisterns) - OH Exposure Pathways fo r Human and Ecological Receptors Pathway Assessment [Complete (C) or Comparison to Screening Incomplete (1)] C rite ria * C 2.8 ug/l 150 ug/l C 5.07 ug/l <150 ug/l I_ c 8.59 ug/l 150 ug/l c 23.6 ug/l < 150 ug/l Unused water sources - OH Ohio River water PWS (WV and OH) I c 1.09 ug/l 150 ug/l c 4.29 ug/l 150 ug/l * Highest value in category is compared to the screening criteria. Screening criteria was established by CATT of 240 mg/kg for soil, 1360 ug/l for aquatic life (surface water), 150 ug/l for drinking water. For complete exposure pathways, all water samples are compared to the drinking water screening criteria to be conservative. No comparison is made for incomplete exposure pathways. 6TT000 1/30/2003 1 of 1 Tab 3.15 Consent Order T&F.xIs Table 4.0 Monitoring Weil Construction and Groundwater Elevation Data Local Landfill Washington, WV Param eters M easuring P oint E levation (feet) LLM W -4 847.55 T otal D epth (feet) W ell D iam eter (in c h e s ) S lot Size (inches) 157.1 4 0.020 Screen Length (feet) Screen Interval (fe e t) 20 710.45690.45 Decem ber-01 January-02 F e b ru a ry -0 2 M arch-02 M ay-02 A u g u s t-0 2 O ctober-02 692.55 715.39 715.28 715.31 714.93 715.52 715.53 M o n ito rin g W ells A -Z o n e B -Z o n e C -Z o n e D -Z o n e LLM W -6 LLM W -9 LLMW -10 LLM W -12B LLM W -11A LLM W -13B LLM W -14B LLM W -11B 796.27 93.09 4 0.020 20 723.18703.18 719.69 720.41 719.76 722.00 721.52 719.77 719.56 788.54 805.94 764.28 81.39 87.75 94.94 442 0.020 0.020 0.010 20 727.15707.15 20 738.19718.19 20 689.34 669.34 G ro u n d w a te r E le va tio n (feet) 727.78 728.06 728.01 728.12 728.48 728.24 728.10 720.67 720.51 720.73 720.90 721.84 722.97 723.01 - - - - 681.93 663.83 42.37 2 0.010 20 641.46621.46 750.80 672.04 139.87 57.28 22 0.010 0.010 15 625.93 610.93 15 629.76 614.76 665.12 115.95 2 0.010 20 569.17549.17 - - - - - 640.42 - - - - - 648.29 - - - 627.74 - 563.60 000120 1/29/2003 1 of 1 Tab 4.0 Consent Order T&F.xIs Table 4.1 Summary of Analytical Results: C-8 in Groundwater Local Landfill Washington, WV Sample LLMW-4 LLMW-6 LLMW-9 | Date | A-Zone 10/15/2002 9/3/2002 5/20/2002 3/28/2002 2/25/2002 1/27/2002 12/13/2001 5/16/2001 5/11/2000 5/19/1999 5/27/1998 4/11/1996 10/15/2002 10/15/02 (dup) 9/3/2002 5/20/2002 3/28/2002 2/25/2002 1/27/2002 12/13/2001 5/16/2001 5/10/2000 5/19/1999 5/27/1998 4/11/1996 10/15/2002 9/3/2002 5/20/2002 3/28/2002 2/25/2002 1/27/2002 12/13/2001 5/16/2001 5/10/2000 5/20/1999 5/27/1998 4/11/1996 C-8 (ug/l) 79.6 63.5 55.7 47.2 50.2 58.4 54.6 1.40 10 16.2 26 39 19.9 17 13.7 18.6 11.5 10.1 12.2 11.9 3 1.42 1.32 9 15 0.0569 NQ NQ NQ NQ NQ ND 0.039 J <0.029 0.046 J <0.1 0.14 1/29/2003 1 of 2 Tab 4.1 Consent Order T&F.xIs 000121 Table 4.1 Summary of Analytical Results: C-8 in Groundwater Local Landfill Washington, WV Sample LLMW-10 LLMW-12B LLMW-11A LLMW-13B LLMW-14B LLMW-11B Date 10/15/2002 9/3/2002 5/20/2002 3/28/2002 2/25/2002 1/27/2002 12/13/2001 5/20/1999 5/28/1998 B-Zone ... 10/8/2002 C-Zone 10/8/2002 10/8/2002 10/9/2002 D-Zone 10/8/2002 C-8 (ug/l) 0.395 0.357 0.56 0.698 1.12 0.162 0.133 0.15 0.22 0.0658 2.22 6.61 0.488 NQ (<0.05) J= estimated value (below laboratory quantitation limit) ND= Not Detected at or above the limit of detection (LOD) NQ= Not Quantifiable. Detected at a concentration above the LOD and below the limit of quantification (LOQ). Note: Analytical method changed as of November 2001 (see Section 2.0 for details). 1/29/2003 2 of 2 Tab 4.1 Consent Order T&F.xIs 000122 Table 4.2 Summary of Analytical Results: C-8 in Surface Water Local Landfill Washington, WV Sample OUTFALL 004 (New) OUTFALL 004 (Old) OUTFALL 005 (New) Date 11/30/2002 10/31/2002 9/30/2002 8/26/2002 7/1/2002 6/13/2002 5/21/2002 4/29/2002 3/26/2002 11/30/2002 10/31/2002 9/30/2002 8/26/2002 7/1/2002 6/13/2002 5/21/2002 4/29/2002 3/26/2002 2/20/2002 1/24/2002 12/13/2001 9/27/2000 12/10/1999 6/3/1999 6/2/1998 5/29/1997 4/2/1996 2/16/1994 11/30/2002 10/31/2002 9/30/2002 8/26/2002 7/1/2002 6/13/2002 5/21/2002 4/29/2002 3/26/2002 C-8 (ug/l) No-flow conditions No-flow conditions No-flow conditions No-flow conditions 11.2 9.29 No-flow conditions 14.5 14.6 No-flow conditions No-flow conditions No-flow conditions No-flow conditions 11.6 10 No-flow conditions 15 1.54 10.9 11.4 No-flow conditions 4.73 7.1 3.06 12 13 13 11 No-flow conditions No-flow conditions No-flow conditions No-flow conditions No-flow conditions No-flow conditions No-flow conditions 34.3 16 1/29/2003 1 of 2 Tab 4.2 Consent Order T&F.xIs 000123 Table 4.2 Summary of Analytical Results: C-8 in Surface Water Local Landfill Washington, WV Sample | OUTFALL 005 (Old)/SS1 OUTLET 101 LM1 (Leachate)/lnlet 002 Date 11/30/2002 10/31/2002 9/30/2002 8/26/2002 7/1/2002 6/13/2002 5/21/2002 4/29/2002 3/26/2002 2/20/2002 1/11/2002 12/13/2001 9/27/2000 12/10/1999 6/3/1999 6/2/1998 5/29/1997 4/2/1996 2/16/1994 11/19/2002 10/31/2002 9/30/2002 8/26/2002 7/1/2002 6/13/2002 5/21/2002 4/29/2002 3/25/2002 2/20/2002 1/23/2002 12/13/2001 9/14/2000 6/3/1999 6/2/1998 11/21/2002 C-8 (ug/l) No-flow conditions No-flow conditions No-flow conditions No-flow conditions 32.1 27.3 No-flow conditions 40.9 39 46 51.4 No-flow conditions 13.3 34 6.8 39 41 39 35 76.7 78.6 115 70.3 63 38 40 48.2 36.4 63.1 81.4 82.4 12 15 54 120 Note: Analytical m ethod changed as of N ovem ber 2001 (see Section 2.0 of DuPont (2003b)for details). 1/29/2003 2 of 2 Tab 4.2 Consent Order T&F.xIs 000124 O Table 4.3 Summary of On-site and Off-site Exposure Pathways Evaluation Local Landfill !____________________ C-8 Im pacted M edia O n-SIte SWMUs/Landfilled Materials Soil Leachate Surface Water Groundwater C-8 Im pacted M edia O ff-S ite Drinking Water (wells, springs and/or cisterns) Local Non-drinking water (wells, springs and/or cisterns) Local E xp o su re P athw ays E valuatio n Hum an H ealth E xposure P athw ays E co lo g ica l E xposure P athw ays Pathw ay A ssessm ent !Pathw ay A ssessm ent (C om plete o r C om parison to S creening ;(C om plete o r |C om parison to S creening Incom plete) C rite ria * Incom plete) C rite ria * I j -- I I ; Ii - Ii c 120 ug/l < 1 5 0 ug/l ! C ; 115 ug/l < 150 ug/l c 115 ug/l < 150 ug/l C 115 ug/l < 1 5 0 ug/l I r" :I E xposure P athw ays fo r Hum an and E co lo g ica l | R eceptors Pathw ay A ssessm ent [C om plete (C ) o r C om parison to S creening Incom plete (1)] C rite ria * c 2.8 ug/l 1 5 0 ug/l i ! C 5.07 ug/l <150 ug/l j j Unused water sources I !! i * Highest value in category is compared to the screening criteria. Screening criteria was established by CATT of 240 mg/kg for soil, 1360 ug/l for aquatic life (surface water), 150 ug/l for drinking water. For complete, all water samples are compared to the drinking water screening criteria to be conservative. No comparison is made for incomplete exposure pathways. 000125 1/30/2003 1 of 1 Tab 4.3 Consent Order T&F.xIs Table 5.0 Summary of Off-site Sampling Program (C-8 Sampling) Letart Landfill Letart, WV Wells Homes RESIDENTIAL SAMPLING FOR 1-MILE RADIUS Number of homes contacted (1) Number of homes surveyed (1) Number of wells Identified (2) Number of wells sampled (2) Number of wells sampled that are used for drinking water Number of cisterns identified <2) Number of cisterns sampled (2> Number of cisterns sampled that are used for drinking water Number of springs identified (2) Number of springs sampled (2) 48 46 42 30 11 4 0 0 0 0 Cisterns Samples Springs Number of springs sampled that are used for drinking water Total number of samples 0 30 Total number of collected samples used for drinking water 11 Note: Field duplicates not considered in sample count. (1> During this investigation, homeowners/residents identified within the sampling radius were contacted to determine residential water usage. Up to two contacts were attempted at each residence. After the second contact attempt, a voluntary survey was left at the residence. Because not all homeowners/residences to the survey, the number of residences surveyed Is less than the number of homes contacted. (2)Some w ater sources (e.g. wells, cisterns, springs) identified during the survey were not sampled. In many cases, sampling of these water sources was refused by the homeowners/residents. In other cases, the water sources were either not accessible or damaged. As a consequence, the number of water sources sampled was less than the number of water sources identified. 2/4/2003 1 of 1 Tab 5.0 Consent Order T&F.xIs 000126 O Table 5.1 Summary of C-8 Analytical Results In Groundwater (ug/l) Letart Landfill (Off-site Wells - One Mile Radius) Letart, WV Sample ID Sample Date C-tt ug/l Well U u 1 Comments Sample ID ............ C-8 Sample Date ug/l OS-BRINKERA 12/11/2001 0.139 Drinking Water OS-GERLACHBA 1/16/2002 0.636 OS-DUTYKL 12/12/2001 ND (0.010) Drinking Water OS-GERLACHC 12/14/2001 ND (0.010) OS-GERLACHL OS-GRIMMG 12/11/2001 12/10/2001 ND (0.010) ND (0.010) Drinking Water Drinking Water OS-GRIMMR2 OS-JORDANS2 1/16/2002 1/17/2002 ND (0.010) ND (0.010) OS-GRIMMR OS-JORDANS1 12/11/2001 1/17/2002 ND (0.010) ND (0.010) Drinking Water Drinking Water OS-JORDANS3 OS-KEARNSMG 1/17/2002 12/10/2001 ND (0.010) ND (0.010) OS-JUDGET 12/10/2001 ND (0.010) Drinking Water OS-PAINTERJ 12/11/2001 ND (0.010) OS-PARSONSR 12/14/2001 ND (0.010) Drinking Water OS-PARSONSR2 2/27/2002 ND (0.010) OS-SAYRET 12/11/2001 NQ (<0.050) Drinking Water OS-RICHARDSOND 12/11/2001 ND (0.010) OS-SHIELDSD 12/10/2001 ND (0.010) Drinking Water OS-ROTTGENRD 1/16/2002 ND (0.010) OS-STEWARTA 12/13/2001 NQ (<0.050) Drinking Water OS-SLEETHTR 1/17/2002 ND (0.010) OS-STEWARTA 12/13/2001 NQ {<0.050) Drinking Water, duplicate OS-STEWARTA2 2/27/2002 ND (0.010) OS-BIGBENDBHC 1/24/2002 ND (0.010) Unused OS-THACKERC 12/12/2001 NQ (<0.050) DUPONT LET1 1/17/2002 NQ (<0.050) Unused OS-THOMASC 12/10/2001 ND (0.010) OS-FRIENDW OS-FRIENDW 1/16/2002 1/16/2002 ND (0.010) ND (0.010) Unused Unused, duplicate OS-THOMASU OS-VAUGHANJ 12/12/2001 12/13/2001 ND (0.010) ND (0.010) * Drinking Water (highlighted in bold blue) ind cates human consumption. Non-drinking Water uses include livestock watering, gardening and any other non-human consumption water uses. ND = Not Detected at or above the limit of detection (LOD). The listed LOD is approximate and varies by instrument and over time. NQ = Not Quantifiable. Detected at a concentration above the LOD and below the limit of quantification (LOQ). All C-8 results are reported in ug/l. Miscellaneous water use is not used for drinking. Well Use' Comments Unused Miscelaneous Unused Unused Unused Miscelaneous Miscelaneous Unused Miscelaneous Unused Unused Unused Miscelaneous Miscelaneous Miscelaneous Miscelaneous 000127 1/29/2003 10:11 AM 1 of 1 Tab 5.1 Consent Order T&F.xIs Table 5.2 Monitoring Well Construction and Groundwater Elevation Data Letart Landfill Letart, WV Zone Param eters M easuring P oint E levation (feet) Total Depth (feet) D-E Zone (con't) LM W -13A LM W -14A Monitoring Wells F-Zone f, r . LMW -2A LMW -6 LMW -10 LMW-11 LMW -13B Vr LMW -14B Under F-Zone LM W -9 766.25 152.35 766.91 158.72 780.87 182.17 755.99 176.43 734.37 191.55 776.21 166.54 765.86 192.27 767.10 202.00 777.85 230.87 W ell D iam eter (inches) S lo t Size (inches) 4 0.010 4 0.010 4 0.010 4 0.010 4 0.010 4 0.010 4 0.010 4 0.010 4 0.010 Screen Length (feet) E levation o f Screen Interval (fe e t) D ecem ber-01 January-02 February-02 M arch-02 M ay-02 A ugust-02 O ctober-02 20 20 30 30 20 25 20 20 20 655.10635.10 - - - 621.07 628.19608.19 - 627.04 628.70 598.70 NA 622.19 622.23 622.44 622.28 622.44 622.38 609.56 679.56 562.82 542.82 634.67 609.67 Groundwater Elevation (feet) NA 582.26 581.97 581.82 581.97 582.34 582.05 NA 543.37 543.36 543.39 543.39 543.26 543.35 NA 619.58 620.70 620.99 621.28 621.52 621.10 593.59 573.59 V- - 582.86 585.10565.10 566.98 - 546.98 - 569.31 NA 552.12 551.96 551.79 551.24 552.51 551.73 NA = Instrument limitations 1/29/2003 2 of 2 Tab 5.2 Consent Order T&F.xIs 00012 O Table 5.2 Monitoring Well Construction and Groundwater Elevation Data Letart Landfill Letart, WV Zone Parameters Measuring Point Elevation (feet) Total Depth (feet) LMW-1 A-Zone LMW-7 Monitoring Wells CZone LMW-8 LMW-3 LMW-5A isaS iS D/E-Zone LMW-3A LMW-4 LMW-5B LMW-12 768.93 31.50 770.24 36.73 777.06 40.60 676.47 30.61 647.22 30.67 674.79 59.59 651.58 28.66 646.22 71.56 742.62 107.52 Well Diameter (inches) 2 4 4 2 4 4 2 4 4 Slot Size (inches) 0.010 0.010 0.010 0.010 Screen Length (feet) Elevation of Screen Interval (feet) 5 742.43 737.43 December-01 January-02 F e b r u a r y -02 March-02 May-02 August-02 October-02 752.62 752.82 752.65 752.10 750.27 751.98 751.02 NA = Instrument limitations 1/29/2003 10 743.51 733.51 749.73 752.25 751.87 751.56 751.16 751.49 751.75 9 745.46 736.46 745.04 746.76 745.05 746.24 745.41 744.95 745.43 5 10 5 650.86 645.86 626.55 616.55 620.20 615.20 Groundwater Elevation (feet) 646.82 648.19 648.07 648.47 646.74 646.53 646.77 619.22 618.76 618.10 617.61 617.50 617.36 617.23 617.4 616.76 615.37 614.80 615.27 615.54 615.84 1 of 2 5 20 20 627.92 622.92 594.66 574.66 655.10635.10 628.08 642.79 639.99 643.30 643.08 636.02 632.47 596.31 596.64 596.34 596.86 596.66 596.25 596.86 635.47 Tab 5.2 Consent Order T&F.xIs 000129 1/29/2003 Table 5.3 Summary o f Analytical Results: C-8 in Groundwater Letart Landfill Letart, WV S a m p le LMW-1 LMW-7 LMW-8 A -Z o n e W e lls D a te 10/14/2002 8/29/2002 5/24/2002 3/29/2002 2/24/2002 1/26/2002 12/10/2001 7/19/2001 1/31/2001 10/4/2000 7/24/2000 4/3/2000 1/13/2000 10/21/1999 7/20/1999 5/28/1998 7/23/1997 4/17/1996 11/22/1991 3/22/1991 10/14/2002 8/27/2002 5/24/2002 3/29/2002 2/24/2002 1/26/2002 12/10/2001 7/20/2001 1/31/2001 10/4/2000 7/25/2000 4/3/2000 1/13/2000 10/20/1999 7/20/1999 5/28/1998 7/23/1997 4/17/1996 11/22/1991 10/14/2002 8/29/2002 5/24/2002 3/29/2002 2/23/2002 1/26/2002 12/10/2001 7/19/2001 1/30/2001 10/4/2000 7/24/2000 4/3/2000 1/13/2000 10/20/1999 7/20/1999 5/28/1998 7/23/1997 4/17/1996 11/22/1991 C - 8 ( u g / l) 25900 23000 30500 20600 18400 29400 24600 6100 9190 10600 8990 13600 17400 12600 6920 24000 5100 1700 68 60 300 197 567 324 180 496 334 242 249 231 158 211 219 339 78.3 260 53 15 0.1 3480 3100 4020 3520 2230 3930 3240 1120 2650 2300 2160 2180 2100 3260 1790 2700 2000 2200 280 1 of 4 000130 Table 5.3 Consent Order T&F.xIs 1/29/2003 Table 5.3 Summary o f Analytical Results: C-8 in Groundwater Letart Landfill Letart, WV I S a m p le LMW-3 LMW-5A S a m p le LMW-3A LMW-4 S a m p le LMW-5B C -Z o n e W e lls D a te 10/11/2002 8/26/2002 5/24/2002 3/27/2002 2/24/2002 1/29/2002 12/13/2001 11/22/1991 3/22/1991 10/11/2002 8/26/2002 5/21/2002 3/27/2002 2/23/2002 1/26/2002 12/11/2001 11/22/1991 3/22/1991 D /E -Z o n e W e lls D a te 10/11/2002 8/26/2002 5/24/2002 3/27/2002 2/23/2002 1/26/2002 12/11/2001 7/19/1999 11/22/1991 3/22/1991 10/11/2002 8/27/2002 5/21/2002 3/27/2002 2/23/2002 1/26/2002 12/13/2001 4/3/2000 1/14/2000 11/22/1991 3/28/1991 D /E -Z o n e W e lls D a te 10/11/2002 10/11/02 (dup) 8/27/2002 8/27/02 (dup) * 5/21/2002 5/21/02 (dup)* 3/27/2002 3/27/02 (dup) 2/23/2002 2/23/02(dup) 1/26/2002 1/26/02 (dup) 12/11/2001 7/20/2001 7/20/01 (dup) C - 8 ( u g / l) NQ (<0.05) Dry no sample 2270 1760 1920 1700 1520 1000 390 112 Dry no sample 87.6 93.6 82.2 99.3 94.4 0.8 1.6 C - S ( u l) 204 Dry-no sample 134 132 101 98.6 100 60.3 350 380 2840 1410 1690 2620 2250 3060 1580 272 172 830 690 C - 8 ( u g / l) 2230 2280 1480 1340 1720 1630 1810 1850 1460 1490 1780 1890 1880 483 592 I 000131 2 of 4 Table 5.3 Consent Order T&F.xIs 1/29/2003 Table 5.3 Summary o f Analytical Results: C-8 in Groundwater Letart Landfill Letart, WV S a m p le LMW-12 LMW-13A LMW-14A S a m p le LMW-2A S a m p le LMW-6 LMW-10 D /E -Z o n e W e lls ( C o n t ) D a le 1/31/2001 10/5/2000 10/5/00 (dup) 7/25/2000 4/3/2000 4/3/00 (dup) 1/14/2000 10/21/1999 10/21/99 (dup) 7/20/1999 7/23/1997 9/20/1994 3/15/1994 11/22/1991 3/22/1991 10/10/2002 10/10/2002 10/10/2002 C -8 (u g/Q 615 1190. J 780 900. J 1100 1020 1030 1750 1700 445 480 530 1200 380 340 Dry-no sample 510 974 F -Z o n e W e lls D a te 10/14/2002 8/27/2002 5/24/2002 3/29/2002 2/24/2002 1/26/2002 12/11/2001 7/19/2001 1/30/2001 10/5/2000 7/25/2000 4/3/2000 1/14/2000 10/21/1999 7/20/1999 5/28/1998 7/23/1997 4/17/1996 9/20/1994 3/15/1994 11/22/1991 3/22/1991 C - 8 ( u g / l) 931 676 922 717 714 740 830 242 423 248 275 306 453 370 350 990 460 460 270 260 63 50 F -Z o n e W e lls D a te 10/14/2002 8/27/2002 5/24/2002 3/29/2002 2/24/2002 1/26/2002 12/11/2001 1/13/2000 5/28/1998 11/22/1991 3/22/1991 10/17/2002 8/29/2002 5/21/2002 C - 8 ( u fl/ l) 15.1 10.5 20.7 14.8 14.9 18.1 15.8 9.4 30 24 25 Instrumentation problems-Not sampled Pump problems-Not sampled 0.298 3 of 4 Table 5.3 Consent Order T&F.xIs 000132 Table 5.3 Summary o f Analytical Results: C-8 in Groundwater Letart Landfill Letart, WV S a m p le LMW-10 (Cont.) LMW-11 LMW-13B LMW-14B S a m p le LMW-9 F -Z o n e W e lls D a te - w - 3/27/2002 2/23/2002 1/26/2002 12/13/2001 10/14/2002 8/27/2002 5/21/2002 3/29/2002 2/24/2002 1/26/2002 12/11/2001 10/10/2002 10/10/2002 Under F-Zone W e l l s D a te 10/17/2002 8/29/2002 5/24/2002 3/27/2002 2/23/2002 1/26/2002 12/10/2001 10/7/1992 M (u g fl) 0.136 0.126 0.133 0.134 0.121 0.058 0.069 0.119 0.112 0.159 0.128 0.0956 105 0.907 0.479 0.715 0.631 0.617 0.875 0.845 0.2 0 & c1 1 J = estimated value (below laboratory quantitation limit). Note: Analytical method changed as of November 2001 (see Section 2.0 of DuPont (2003b) fo details). ` Analytical duplicates' values were previously inadvertently omitted from the tables. 1/29/2003 4 of 4 000133 Table 5.3 Consent Order T&F.xIs 1/29/2003 Table 5.4 Summary of Analytical Results: C-8 in Surface Water Letart Landfill Letart, WV Sam ple 002(LEACHATE BASIN) 003 STORMWATER RUNOFF RT 33 STREAM BRINKER RUN D a te 11/25/2002 10/31/2002 9/27/2002 8/30/2002 7/30/2002 6/28/2002 5/30/2002 4/30/2002 3/28/2002 2/19/2002 1/25/2002 12/14/2001 11/27/2001 7/20/2001 7/25/2000 4/3/2000 1/14/2000 10/21/1999 11/30/2002 10/31/2002 9/27/2002 8/30/2002 7/30/2002 6/28/2002 5/30/2002 4/30/2002 3/28/2002 2/19/2002 1/25/2002 12/14/2001 9/27/2002 10/31/2002 9/27/2002 8/30/2002 5/30/2002 4/30/2002 3/28/2002 2/19/2002 1/25/2002 7/20/2001 7/31/2000 7/20/1999 7/23/1997 4/17/1996 10/14/2002 C-8 (ug/l) 939 645 4.52 2050 1410 Not Analyzed* 1630 443 131 355 50.1 36.1 53.2 159 1350 1900 920 3240 No-Flow Conditions No-Flow Conditions 0.17 No-Flow Conditions No-Flow Conditions Not Analyzed* 0.282 0.0653 0.198 No-Flow Conditions 0.148 0.39 50.9 2.83 2.24 No-Flow Conditions 1.57 0.845 1.26 3.92 1.9 2.01 0.573 2.23 2 1.8 0.0612 1 of 2 Table 5.4 Consent Order T&F.xIs 000134 Table 5.4 Summary of Analytical Results: C-8 in Surface Water Letart Landfill Letart, WV S am ple CAP RUNOFF Date 11/25/2002 10/31/2002 8/30/2002 6/28/2002 5/30/2002 4/30/2002 3/28/2002 2/19/2002 1/25/2002 C-8 (ug/l) 65.1 102 No-Flow Conditions Not Analyzed* 371 279 Not Sampled No-Flow Conditions 119 Note: Analytical method changed as of Novem ber 2001 (see Section 2.0 of DuPont (2003b) for details). * Samples were taken at the respective surface water locations. However, due to an error by the courier, the samples arrived at the lab warm and were not analyzed. 1/29/2003 2 of 2 Table 5.4 Consent Order T&F.xIs 000135 Table 5.5 Summary of On-site and Off-site Exposure Pathways Evaluation Letart Landfill Letart, WV _________ _________________________________ Exposure Pathways Evaluation Hum an H ealth E xposure Pathw ays E cologica l E xposure Pathw ays Pathw ay A ssessm ent Pathw ay A ssessm ent C-8 Im pacted M edia O n-Site SWMUs/Landfilled Materials Soil Leachate ** Surface Water Groundwater (C om plete o r Incom plete) I I C C I C om parison to S creening C rite ria * -- -- * 2050 ug/l > 150 ug/l 371 ug/l > 1 5 0 ug/l - (C om plete o r Incom plete) I I C C I C om parison to S creening C rite ria * -- * 2050 ug/l > 1 5 0 ug/l 371 ug/l > 1 5 0 ug/l -- E xposure Pathw ays fo r Hum an and E co lo g ica l R eceptors Pathw ay A ssessm ent [C om plete (C) o r C om parison to S creening C-8 Im pacted M edia Incom plete (I)] C rite ria * O ff-S ite Drinking Water Wells - Letart C 0.139 ug/l 1 5 0 ug/l Non-drinking Water Wells - Letart C NQ(<0.050) 1 5 0 ug/l Unused water sources - Letart Ohio River water I c 0.128 u g / l 150 ug/l -- -------- ----------------- * Highest value in category is compared to the screening criteria. Screening criteria was established by CATT of 240 mg/kg for soil, 1360 ug/l for aquatic life (surface water), 150 ug/l for drinking water. For complete exposure pathways, all water samples are compared to the drinking water screening criteria to be conservative. No comparison is made for incomplete exposure pathways. ** Highest C-8 concentration (since the landfill cap installation in April 2001 ) is shown. 000136 1/30/2003 1 of 1 Tab 5.5 Consent Order T&F.xIs Table 6.0 Summary of Off-site Sampling Program (C-8 Sampling) Dry Run Landfill Lubeck, WV Wells Homes RESIDENTIAL SAMPLING FOR 1-MILE RADIUS Number of homes contacted (1) Number of homes surveyed (1) Number of wells identified (2) Number of wells sampled (2) 75 64 41 37 Cisterns Number of wells sampled that are used for drinking water Number of cisterns identified (2) Number of cisterns sampled (2) 13 17 8 Number of cisterns sampled that are used for drinking water Number of springs identified (2) Number of springs sampled (2) 1 8 8 Samples Springs Number of springs sampled that are used for drinking water Total number of samples 1 53 Total number of collected samples used for drinking water 15 Note: Field duplicates not considered in sample count. (1) During this investigation, homeowners/residents identified within the sampling radius were contacted to determine residential water usage. Up to two contacts were attempted at each residence. After the second contact attempt, a voluntary survey was left at the residence. Because not all homeowners/residences to the survey, the number of residences surveyed is less than the number of homes contacted. (2) Some water sources (e.g. wells, cisterns, springs) identified during the survey were not sampled. In many cases, sampling of these water sources was refused by the homeowners/residents. In other cases, the water sources were either not accessible or damaged. As a consequence, the number of water sources sampled was less than the number of water sources identified. 000137 2/4/2003 1 of 1 Tab 6.0 Consent Order T&F.xis TABLE 6.1 Summary of C-8 Analytical Results In Groundwater and Surface Water (ug/l) Dry Run Landfill (Off-site Wells, Springs, and Cisterns - One Mile Radius) Lubeck, WV Sample ID OS-ABBOTTRL OS-ABBOTTRL OS-ABBOTTS OS-ABBOTTS OS-ANDERSONCD OS-ATKINSONJ2 OS-ATKINSONJ2 OS-ATKINSONM OS-BAKERH OS-HOPKINSKE OS-HORNBECKJW OS-MORRISONM OS-NICHOLSONDH OS-PARKERJL OS-SHEPHERDM OS-WESTBROOKLM OS-SEEBAUGHR OS-NICHOLSONDH2 Sample Date 12/11/2001 4/11/2002 12/12/2001 4/11/2002 12/13/2001 1/9/2002 4/12/2002 12/12/2001 12/14/2001 12/11/2001 12/13/2001 2/4/2002 12/11/2001 12/10/2001 2/4/2002 12/12/2001 2/26/2002 2/4/2002 C-H ug/l 0.0606 NQ (<0.050) 0.22 0.422 ND (0.010) 0.149 0.264 ND (0.010) 0.339 NQ (<0.050) ND (0.010) ND (0.010) 0.0505 0.177 NQ (<0.050) ND (0.010) 0.273 0.242 Water U s e" Comments Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water Drinking Water OS-ATKINSONJ1 1/9/2002 ND (0.010) Misc. OS-BAKERHK2 2/20/2002 NQ (<0.050) Unused OS-CHANEYG 2/14/2002 0.164 Unused OS-COBBAJ 12/11/2001 0.0639 Misc. OS-COBBAJ2 1/15/2002 ND (0.010) Unused OS-DAVISA2 OS-GRIENERD1 2/13/2002 2/5/2002 NQ (<0.050) NQ (<0.050) Unused Misc. OS-GROSED 2/15/2002 ND (0.010) Unused OS-HARRISRE OS-HOFMANNDE OS-HOPEWELL 2 12/12/2001 12/12/2001 1/26/2002 ND (0.010) 0.354 ND (0.010) Unused Unused Unused OS-JONESDR OS-KAUFMAND OS-LOBBINSJ OS-ROBERTSDR 12/13/2001 1/11/2002 2/12/2002 1/18/2002 0.0614 ND (0.010) 0.078 ND (0.010) Misc. Unused Unused Unused * Drinking Water (highlighted in bold blue) indicates human consumption. Non-drinking Water uses include livestock watering, gardening and any other non-human consumption water uses. ND = Not Detected at or above the limit of detection (LOD). The listed LOD is approximate and varies by instrument and over time. NQ = Not Quantifiable. Detected at a level above the LOD and below the limit of quantification (LOQ). All C-8 results are reported in ug/l. Misc. = Miscellaneous water use is not used for drinking. Data highlighted in yellow are results for water sources located in the one-mile radius that were resampled during the two-mile radius sampling event. sample Type Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well Spring Cistern Well Well Well Well Well Well Well Well Well Well Well Well Well Well Well 1/29/2003 4:18 PM 1 of 2 Tab 6.1 Consent Order T&F.xis] 000138 TABLE 6.1 Summary of C-8 Analytical Results In Groundwater and Surface Water (ug/l) Dry Run Landfill (Off-site Wells, Springs, and Cisterns - One Mile Radius) Lubeck, WV Sample ID OS-SHEPHERDP OS-VANDYNEHR OS-VANDYNEHR OS-VANDYNEHR1 OS-WHITEEE OS-WIGALR OS-WIGALR1A OS-WIGALCA OS-WINTERSJ OS-WRIGHTLE DUPONT DR2 DUPONT DR3 OS-ATKINSONJ3 OS-CAMPG3 OS-CAMPG2 OS-DOWLERE2 OS-DOWLERE2 OS-RHODESR OS-SEEBAUGHV OS-TENNANTJD OS-CAMPG1 OS-DALEL OS-DAVISA1 OS-DOWLERE1 DUPONT DR3A OS-GRIENERD2 OS-HOPEWELL 1 OS-MOYERSV Sample Date 12/14/2001 12/13/2001 12/13/2001 1/11/2002 2/20/2002 1/14/2002 1/26/2002 4/3/2002 12/11/2001 4/29/2002 1/2/2002 1/2/2002 4/12/2002 2/28/2002 2/28/2002 1/28/2002 1/28/2002 2/4/2002 2/26/2002 2/8/2002 2/28/2002 2/28/2002 2/8/2002 1/28/2002 1/28/2002 2/5/2002 1/11/2002 2/28/2002 C-8 ug/l NQ (<0.050) ND (0.010) ND (0.010) 0.694 NQ (<0.050) NQ (<0.050) 0.127 NQ (<0.05) 0.166 0.839 0.68 Water Use............ Comments Misc. Unused duplicate Unused Unused Unused Unused Unused Misc. Unused Unused Unused 0.625 0.0998 0.081 0.347 0.35 0.0748 0.278 0.107 Non-drinking water Water Cattle Water Cattle Water Cattle duplicate Misc., Water Cattle Unused Unused 0.338 0.54 0.446 0.307 0.175 0.409 0.743 0.974 Misc. Misc. Unused Misc. Unused Misc. Unused Unused sample Type Well Well Well Well Well Well Well Well Well Well Well Well Spring Spring Spring Spring Spring Spring Spring Spring Cistern Cistern Cistern Cistern Cistern Cistern Cistern Cistern * Drinking Water (highlighted in bold blue) indicates human consumption. Non-drinking Water uses include livestock watering, gardening and any other non-human consumption water uses. ND = Not Detected at or above the limit of detection (LOD). The listed LOD is approximate and varies by instrument and over time. NQ = Not Quantifiable. Detected at a level above the LOD and below the limit of quantification (LOQ). All C-8 results are reported in ug/l. Misc. = Miscellaneous water use is not used for drinking. 1/29/2003 4:18 PM 2 of 2 Tab 6.1 Consent Order T&F.xIs] 000139 T ab le 6.2 M o n ito rin g W e ll C o n s tru c tio n and G ro u n d w a te r E le v a tio n Data D ry Run L a n d fill Lubeck, WV Monitoring Wells Zone Overburden A-Zone Param eters Measuring Point Elevation (feet) Total Depth (feet) Well Diameter (inches) Slot Size (inches) Screen Length (feet) Screen Interval (feet) December-01 January-02 February-02 March-02 M ay-02 August-02 October-02 DRMW-6A DRMW-12A DRMW-12B DRMW-13A DRMW-21A DRMW-16B DRMW-17B DRMW-18B 744.46 11.89 2 0.010 737.81 738.29 738.26 738.75 738.25 735.61 736.92 732.41 17.17 4 0.010 5 720.24 715.24 727.30 728.50 727.99 728.89 728.97 725.51 725.91 732.85 20.24 722.57 13.33 707.62 19.79 44 2 0.010 0.010 0.010 10 722.61 712.61 5 714.24 709.24 10 697.83 687.83 Groundwater Elevation (feet) 728.11 729.14 728.70 729.58 729.67 726.24 726.64 714.35 716.97 714.16 716.68 716.70 713.62 713.97 - - - - 703.00 792.98 61.61 4 0.010 20 751.37731.57 - - - 736.49 853.56 127.09 4 0.010 20 746.47 726.47 - - - - - 737.19 925.87 202.05 4 0.010 20 743.82 723.82 - 757.47 Zone P aram eters Measuring Point Elevation (feet) Monitoring Wells A-Zone (cont) B-Zone DRMW-19B DRMW-20B DRMW-12 DRMW-13 881.99 868.79 733.1 722.68 C-Zone Above AZone DRMW-15 DRMW-21B DRMW-14 734.28 707.67 938.08 Total Depth (feet) Well Diameter (inches) Slot Size (inches) Screen Length (feet) Screen interval (feet) 151.76 4 0.010 20 750.23 730.23 December-01 January-02 February-02 March-02 May-02 August-02 October-02 - _ - 750.94 136.41 37.82 37.54 48.60 44 4 2 0.010 0.010 0.010 0.010 20 752.38 732.38 15 710.28695.28 15 700.14685.14 Groundwater Elevation (feet) - - 752.95 724.40 725.25 725.40 725.74 725.99 723.65 723.54 711.81 712.17 711.46 712.21 712.54 710.65 711.65 20 705.68 685.68 716.10 716.50 716.33 717.02 716.88 715.82 716.02 177.20 4 0.010 20 550.47 530.47 _ - _ - 613.01 239.91 10 NA NA NA 754.09 757.99 754.87 755.45 755.12 755.31 755.13 J014O 1/29/2003 1 of 1 Tab 6.2 Consent Order T&F.xIs Table 6.3 Summary of Analytical Results: C-8 in Groundwater Dry Run Landfill Lubeck, WV S am ple DRMW-6A DRMW-12A DRMW-12B | D ate | O verburden 10/9/2002 8/28/2002 5/22/2002 3/30/2002 2/20/2002 1/27/2002 12/12/2001 7/20/2000 7/21/1999 5/26/1998 7/22/1997 4/10/1996 10/9/2002 8/28/2002 5/22/2002 3/30/2002 2/20/2002 1/25/2002 12/12/2001 7/19/2000 7/21/1999 5/26/1998 7/22/1997 4/10/1996 10/9/2002 10/9/02 (dup) 8/28/2002 5/22/2002 3/30/2002 3/30/02 (dup) 2/20/2002 1/25/2002 1/25/02 (dup) 12/12/2001 7/20/2000 7/21/1999 6/16/1998 C -8 (u g /l) 1.13 0.785 1.24 0.843 0.822 0.824 1.04 0.212 0.096 0.27 0.36 0.19 0.181 0.088 0.0832 0.0785 0.125 0.168 0.158 0.128 0.081 J <0.10 <0.1 <0.1 0.258 0.242 NQ NQ NQ NQ NQ 0.073 0.085 0.215 ND (0.029) 5.4 <0.1 1/29/2003 1 of 3 000141 Tab 6.3 Consent Order T&F.xIs 1/29/2003 Table 6.3 Summary of Analytical Results: C-8 in Groundwater Dry Run Landfill Lubeck, WV S am ple DRMW-13A DRMW-21A DRMW-16B DRMW-17B DRMW-18B DRMW-19B DRMW-20B DRMW-14 DRMW-12 | D ate | O verburden 10/9/2002 8/28/2002 5/22/2002 3/30/2002 2/20/2002 1/25/2002 12/12/2001 7/20/2000 7/21/1999 5/26/1998 7/22/1997 4/10/1996 4/10/1996 (dup) 10/9/2002 A -Z one W e lls 10/8/2002 10/8/2002 10/7/2002 10/7/2002 10/8/2002 A b o ve A -Z one W e lls 10/15/2002 8/28/2002 5/22/2002 3/30/2002 2/20/2002 1/27/2002 12/12/2001 7/20/2000 7/21/1999 6/16/1998 7/21/1997 4/10/1996 B -Z one W e lls 10/9/2002 8/28/2002 5/22/2002 3/30/2002 2/20/2002 C-8 (u g /l) 6.66 5.14 2.31 4 3.73 5.97 6.4 9.9 0.070 J 8.7 15 8.2 11 0.27 NQ (<0.05) 0.155 ND (<0.01 ) NQ (<0.05) NQ (<0.05) NQ (<0.05) NQ NQ NQ NQ NQ NQ 0.115 2.5 <0.1 <0.1 <0.1 0.109 0.0626 0.0817 0.0929 0.11 000142 2 of 3 Tab 6.3 Consent Order T&F.xIs Table 6.3 Summary of Analytical Results: C-8 In Groundwater Dry Run Landfill Lubeck, WV S am ple D ate | C-8 (u g /l) B -Zone W e lls (C o n i) 1/25/2002 12/12/2001 0.116 0.086 7/19/2000 0.16 7/21/1999 0.134 5/26/1998 <0.10 7/22/1997 <0.1 4/10/1996 <0.1 DRMW-13 10/9/2002 20.9 8/28/2002 13.1 8/28/02 (dup) * 5/22/2002 14.6 16.9 DRMW-13 (Cont.) 3/30/2002 2/20/2002 1/25/2002 12.6 11.5 16.5 12/12/2001 9.86 7/20/2000 9.8 7/21/1999 3.6 5/26/1998 9.2 7/22/1997 7 B -Zone W e lls DRMW-15 10/15/2002 4.92 8/28/2002 5/22/2002 5/22/02 (dup) * 3.99 5 4.66 3/30/2002 4.91 2/20/2002 1/27/2002 12/12/2001 3.65 4.35 4.94 7/20/2000 7/21/1999 0.763 0.263 C -Zone W e lls DRMW-21B 10/9/2002 NQ (<0.05) ND = Not Detected at or above the limit of detection (LOD). The listed LOD is approximate and varies by instrument and over time. NQ = Not Quantifiable. Detected a quantification (LOQ). J = estimated value (below laboratory quantitation limit). Note: Analytical method changed as of November 2001 (see Section 2.0 of DuPont (2003b) for details). * Analytical duplicates' values were previously inadvertently omitted from the tables. 1/29/2003 3 of 3 00143 Tab 6.3 Consent Order T&F.xIs 1/29/2003 Table 6.4 Summary of Analytical Results: C-8 in Surface Water Dry Run Landfill Lubeck, WV Sam ple OUTLET 001 OUTLET 003 OUTLET 004 Date 11/21/2002 10/30/2002 9/30/2002 8/30/2002 7/31/2002 7/1/2002 6/28/2002 5/28/2002 4/24/2002 3/25/2002 2/25/2002 1/28/2002 12/12/2001 10/3/2000 12/29/1999 5/19/1998 4/9/1996 11/30/2002 10/30/2002 9/30/2002 8/30/2002 7/1/2002 6/28/2002 5/28/2002 4/29/2002 3/26/2002 2/25/2002 1/28/2002 12/12/2001 11/30/2002 10/30/2002 9/30/2002 8/30/2002 7/1/2002 6/28/2002 5/28/2002 4/27/2002 3/26/2002 2/25/2002 1/28/2002 12/12/2001 1 of 3 C-8 (ug/l) 64.6 81.7 No-flow conditions No-flow conditions No-flow conditions No-flow conditions No-flow conditions 30.9 41 71.6 43.9 41.6 No-flow conditions 31.5 66 17 86 No-flow conditions No-flow conditions No-flow conditions No-flow conditions 25.3 No-flow conditions No-flow conditions 20.1 6.77 No-flow conditions No-flow conditions No-flow conditions No-flow conditions No-flow conditions No-flow conditions No-flow conditions 0.7 No-flow conditions No-flow conditions No-flow conditions 158 No-flow conditions No-flow conditions No-flow conditions 00144 Tab 6.4 Consent Order T&F.xIs Table 6.4 Summary of Analytical Results: C-8 in Surface Water Dry Run Landfill Lubeck, WV - Sam ple PROPERTY BOUNDARY STREAM SAMPLING POINT#1 (SS-1) STREAM SAMPLING POINT#2 (SS-2) Date 10/30/2002 8/30/2002 5/28/2002 4/24/2002 3/25/2002 2/25/2002 1/28/2002 12/12/2001 10/3/2000 12/29/1999 7/14/1998 4/9/1996 10/30/2002 8/30/2002 5/28/2002 4/24/2002 3/25/2002 2/25/2002 1/28/2002 12/12/2001 10/3/2000 12/29/1999 5/19/1998 10/30/2002 8/20/2002 5/28/2002 4/24/2002 3/25/2002 2/25/2002 1/28/2002 12/12/2001 10/3/2000 12/29/1999 5/19/1998 C-8 (ug/l) 3.8 No-flow conditions 9.41 6.69 22.8 3.81 11.1 3.99 10.3 39 0.88 9.9 1.63 No-flow conditions 1.63 0.932 1.06 0.85 0.893 1.19 0.758 0.54 1 29.2 No-flow conditions 51 28.9 66.6 24.3 42.4 20.5 27.6 87 4.6 1/29/2003 2 of 3 00145 Tab 6.4 Consent Order T&F.xIs Table 6.4 Summary of Analytical Results: C-8 in Surface Water Dry Run Landfill Lubeck, WV Sam ple Date C-8 (ug/l) DR LEACHATE 10/30/2002 5/28/2002 4/24/2002 3/25/2002 2/25/2002 1/28/2002 12/12/2001 10/3/2000 704 150 237 334 256 398 109 27.4 12/29/1999 5/19/1998 7/22/1997 34 56 62 POND UNDERDRAIN 10/30/2002 5/28/2002 38.8 67.4 4/24/2002 3/25/2002 2/25/2002 33.4 66.7 37.1 1/28/2002 12/12/2001 29.3 35.4 Note: Analytical method changed as of November 2001 (see Section 2.0 of DuPont (2003b) for details). 1/29/2003 3 of 3 Tab 6.4 Consent Order T&F.xIs 00014G Table 6.5 Summary of On-site and Off-site Exposure Pathways Evaluation Dry Run Landfill Lubeck, WV E xposure P athw ay E valuatio n Hum an H ealth E xposure Pathw ays E co lo g ica l E xposure Pathw ays O n-Site C-8 Im pacted M edia SWMUs/Landfilled Materials Soil Leachate (captured & treated) Surface Water Groundwater Pathw ay A ssessm ent (C om plete o r Incom plete) C C I C I C om parison to S creening C rite ria * -- -- -- 87 ug/l < 150 ug/l -- Pathw ay A ssessm ent (C om plete o r Incom plete) C C I c I C om parison to S creening C rite ria * -- -- -- 87 ug/l < 150 ug/l -- E xposure P athw ays fo r Hum an and E co lo g ica l R eceptors O ff-S ite C-8 Im pacted M edia Drinking Water (wells, springs and/or cisterns) - Dry Run Non-drinking water (wells, springs and/or cisterns) - Dry Run Unused water sources - Dry Run P athw ay A ssessm ent [C om plete (C) o r Incom plete (1)] C C I C om parison to S creening C rite ria * 0.422 ug/l 1 5 0 ug/l 0.54 ug/l 1 5 0 ug/I * Highest value in category is compared to the screening criteria. Screening criteria was established by CATT of 240 mg/kg for soil, 1360 ug/l for aquatic life (surface water), 150 ug/l for drinking water. For complete exposure pathways, all water samples are compared to the drinking water screening criteria to be conservative. No comparison is made for incomDlete exposure pathways. 000147 2/4/2003 1 of 1 Tab 6.5 Consent Order T&F.xIs F IG U R E S 00 w? LETART LANDFILL WASHINGTON WORKS FACILITY/ LOCAL LANDFILL DRY RUN LANDFILL ip L S u p jf^ ro u e XZIS- .. . mct-gnri :isvme * #r" ^ \ v^stoclfiort ' Wa y n e N a tl. . ^. D elphi T ? ?cksonw 1/l ^ - - ^ J nu He - \ \ 9 ^ N cxr?jng\ _r--- V n t 'o n ^ i M o a m ,MCAt tmond Dale X" "^W atm o w \ CXbe_ Pl^ains7 + -- w- 1 .Vl Parke rsbjurq Ibany Coolyille^ 51^ .Wellston ^ ^ arrisonville Bellvi. 3 5 ^ j C__h_e__s_t_e_r _____ yer , , Rv. u_t_l_an_d_^__ ..jddleportX /rN : ^f Vi ninttoonl i ' cd a l e / . 1 V. pakH M I^C eo) ^ R a^nsw ood ~ C h e i h '- '- 3 J .4 G { ir\s-r-w >rd C ra n d e r^ C k ^ ,,. / oA lliporrs i Riole.yj jth W a y n e Ntfaatl.. v^---- ^' V E-vaos- LLeeoo.hji^^ X l.1 3 2 < isouthsid L u rn J ^ * ^ ~~ pa ydpa, e n G iti ^ sirte H u ilt'-c ! i_ ... '-> / 0Middlbour . - W i c k e d 111* Mar < a - 7 West u,ni'n\ ^pennsboro Harrisv.ille spulimi an w <Elizabeth " (i oSmithville-: ~V""*T" vCOXS M ...... \ ' Tanner / i ^deriv ili ACrantsville,^ f --i j \ i / vStumptown,- vV oldibur y \ jsan"djeeville umorfriasV\Ksedale;) i } plooneyuijl e /c assaway0 pf: ^W alton . """\ / \ n - ^ r S ^ ^7 A Corporate Remediation Group An Alliance between DuPont an d URS Diamond B a rley Mill Plozo, Building 27 W ilm ington, Delaware 19805 DuPont Washington Works Properties DuPont Washington Works Washington, West Virginia SCM N ot to S colo DATE 1 /1 3 /0 3 OCSIGNCO CHECKED KLD DRAWN DEL APPROVED cad m e NO. 7 4 23 *0 06 FIGURE 1 .0 Tm o 000150 000151 SCALE S B 5B ----------------- A tti mm, KLD mi Am m irano mMBteoHsnucnoN) nat> ^ Corporata Romoditlon Group in ttlKenc Bartn " Roib. BuMns 27 Mmlnftcn, D M m IftQOS ONE- AND TWO-MILE RADIUS SUMMARYOF C-8 RESULTS Washington County, Ohio s s ----------- H Sow 11/8/0* marni 3.2 LEGEND = MONITORING WELL , J17-PW 1 > = PRODUCTION WELL OUUET 005 RBLL1 = OUTFALL SAMPLING POINT = RIVERBANK LANDFILL SEEP AREAS SCALE 700 700' K. OAMS D Ji ENGLISH K. DAWS ppnm toanti MTMLS APMMDCCQHSTRUCnON) C orporate Remediation Group 47i Alliance betw een DuPont anel UHS Diam ond B a rle y Mill Ptaza, B u ild in g 27 W ilm ington, Delowore 19805 MONITORING WELL AND SURFACE WATER SAMPLE LOCATION MAP DuPont Washington Works Focility Washington. West Virginia * (howl j 04/11/^002 j 74230005 j 3.3 CSTOOO 008-MW01 0.126 L04-PW01 (GALLERY WELL) . 143 <*. .120 , r LEGEND , D08-UWD1 = MONITORING WELL J17-PW01 <3- = PRODUCTION WELL 10.3 = CONCENTRATION OF C - 8 ( u g / L ) IN GROUNDWATER 000154 SCALE 700 700' HMD SJO man DEL MIMS TOL WMOtSXKStttO ASH /frwioccCTtfwucnow) Corporate Remediation Group An A llia n c e between DwPont and URS Diamond B a rle y Mill P laza, B u ild in g 27 W ilm ington, D eloare 19805 C -8 IN GROUNDWATER - 4Q02 DuPont Washington Works Facility Washington, West Virginia AeMm 8/24/02 7423800* 000155 1RANSECT LOCATION SAMPLE NUWER X TRANSECT TYPE SAMPLE C-B ugA 10 center mkJ-coumn WW-R-TS-10-2M 0.236 10 center <*p KWK-R-TS-10-2S 0.239 DATE 7/10/02 7/10/02 <cnt> ^wRaUrn OHIO RIVER WATER SAMPLING LOCATIONS-DOWNSTREAM PCL CorporatenemadWtionGrp DuPont Washington Works Facility Washington, West Virginia 1Bo^ UWPio;a imo- oo:? 000156 |1 TRANSECT LOCATION SAMPLE NUMBER M TRANSEC1 TYPE Saille to C -8 ugA DATE 6 OH-side bottom WMK-R-TS-6-3B NO (0.050) 6/27/02 6 OH-side m id-coturno WK-H-1S-6-3M NO (<0.010) 6/27/02 6 OH-side dip WNK-R-TS-6-3S NO (<30.010) 6/27/02 TRANSECT LOCATION SAMPLE NUMBER 3N TRANSE TYPE Sample 0 6 center bottom H K -R -TS-6-2B 6 center mid-column WKK-R-T5-6-2M 6 center <p K-I-TS-6-2S C -8 u g A DATE NO (<O.OtO) 6/27/02 ND (<0.010) 6/27/02 NO {<30.010} 6/27/02 TRANSECT LOCATION SAMPLE NUMBER 3N WANSEC TYPE SAMPLE C -8 ugA DATE 6 WV-side bottom WMK-R-TS-6-1B NO (<0.OtO) 6/27/02 6 WV-side mid-- column WWK-R-TS-6-1M NO (0.010) 6/27/02 6 WV-side dip WMK-R-TS-6-1S ND (<0.010) 6/27/02 WASHINGTON WORKS v FACIUTY ! OHIO 000157 8ST000 NQ-0.102 2200 2200' 4400' W EST VIRGINIA LEGEND; LUBECK (0.313-111) PUBLIC WATER SUPPLY AM) C -8 CONCENTRATION (ug/L) RANGE RIVER TRANSECT 1 M) OHO RIVER WATER SAMPLING LOCATION AM) C -8 CONCENTRATIONS (ug/L) RANGE NOTE: ND = <0.01 ug/L NQ - >0.01 <0.05 ug/L 'a s s a i-------------------KLD MM EMCOUD ASH AHWCKPOICM) wwKW cowsraucnoH) <OEK> ^ C o rp o ra to R a m a d M to n & o u p Orarti amt fW *-C Dlantmt Croup G-6 CONCBmUDONS (ug/L) N TIE OHOnVBI AW PUBLICWAIBI SIPPLE DuPont Washington Works Facility Ohio - West Virginia 8aeiry MM Ploro. 17 tftmmtan, Dekiwxf 19880-00? ? *- / /a t JUBC091 3.7 SAMPLE TYPE SAMPLE 10 C -8 ug/L DATE bottom W *K -R -T S -5 -3 e d-colum n W W K -R -T S -5 -3 M NO ( < 0 .0 1 0 ) 6 / 2 8 / 0 2 ND ( < 0 .0 1 0 ) 6 / 2 8 /0 2 dip W W K - R - T S - 5 - 3 S NO ( < 0 0 1 0 ) 6 / 2 8 / 0 2 dip W I K - R - T S - 5 - 3 S - 2 * NO ( < 0 0 1 0 ) 6 / 2 8 / 0 2 DUPLICATE ^ SAMPLE TYPE SAMPLE ID C -8 ug/L DATE bottom W W K -R -T S -5 -2 8 d-colum n W W < -R -T S -5 -2 M ND (< 0 .0 1 0 ) 6 / 2 8 /0 2 NO (< 0 .0 1 0 ) dip W W K - R - T S - 5 - 2 S NO (< D .0 1 0 ) 6 / 2 8 / 0 2 SAMPLE TYPE SAMPLE ID C -8 ug/L DATE bottom W V fK -R -T S -5 -1 8 d -- colum n W W - R - T S - 5 - 1 U dip W W K - R - T S - 5 - 1 S ND (< 0 .0 1 0 ) 6 / 2 8 /0 2 NO ( < 0.0 10 ) 6 / 2 8 / 0 2 NQ ( < 0 .0 5 0 ) 6 / 2 8 /0 2 Ti TRANSECT LOCATION SAMPLE NUMBER ON 1RANSECT TYPE SAMPLE ID C- 4 O H -sid b ottom W Y H K -R -T S -4-3e ND 4 O H -s id e m id -c o lu m n Y W K -R -T S -4 -3 M ND 4 O H -side dip W W K -R -T S -4 -3 S NO 000160 ILLUSTRATIONS TAKEN FROM SIMARD, 1989. KM 0 MMN ML cxccras WPS pnexp(PC5aw) m tm s IDEALIZED OHIO RIVER VALLEY CROSS-SECTION AND BLOCK DIAGRAM C orporate Remedtatkm Group An AUianct b ttw ien DuPont and URS Diamond DuPont Washington Works Washington, West Virginia *PP(8>CKCOM5tKUCTWN) B a rley Mill P laza , B u ild in g 2 7 W ilm ington, Delaware 19805 Not to Sc* J ii/tfla | n**o * J 3.8 N o rth A PLEISTOCENE TERRACE HOLOCENE FLOODPLAIN LITTLE HOCKING WATER ASSOCIATION OHIO HOLOCENE FLOODPLAIN r S outh A' PLEISTOCENE TERRACE DUPONT WASHINGTON WORKS WEST VIRGINIA Y14-MW02 ELEVATION ( fM t MSL) 000161 -L-E--G-E--N-D-- , 006-MW01 = MONITORING WELL JI7-PW 1 i > = PRODUCTION WELL OUTFAU. 004 ( A = OUTFALL SAMPLING POINT A ____ A = CROSS SECTION LINE SCALE OCSONO SJO gum DEL QCCKED TDl #nm n(D aB 0 MTWLS jm ownKcotsnucnoto CSUPQHJ) ^ C orporate Remediation Group A n A llia n ce b e tw e en andD u P o n t U R S D iam ond B a rley Mill Plazo. Building 2 ? WilmiGQton, Qelow ore 19 80 5 700' CROSS-SECTION LOCATION MAP DuPont W ashington Works Moin P lant W a s h in g to n , W e s t Virginia * Moon J 11/10/01 J 74228000 | 3 .1 0 maam 000162 < <I s5tr g - OcOo0e0o: _c sO t S 11 nI5 I *a E g" sil ? o Q i i i i o CN 0 0 0 16 4 North South Topsoil - OL nu rrm1 1 Sand - SM.SC.SP sut - ml | A ' 1 Sand and Gravel - SW.GP.GW.GM LEGEND: 1 _/\ Z2 Peat - PT Bedrock a / - cl ^pT S ta tic Water Level, Dec. 1991 _______ A ppro xim ate Geologic C o nta ct ----------- S ta tic Water Level, Inferred ---------- G roundwater Flow Direction DCS OfWWN Of! HCKCD *PRCVCP(OCSO<) APPSOVEKCONSIRUCTIO) (SUM P C orporate Rem ediation Group An AUxance between DuPont and URS Diamond B crte y Mill P lozo, B u ild in g 21 W ilm ington, Delawore 19805 CROSS-SECTION C -C ' DuPont W oshington Works Main Plant W ashington, W est V irg in ia 0 0 0 16 5 North D R B LM W -9 B -2 9 B G M W -2 Z07-MW01 (TW-22) B -3 8 I M Topsoil - OL S Fill 1 Sand - SM,SC,SP u m Silt - ML fp .' ] Sand and Gravel - SW.GP.GW.GM LEGEND: EXSd Peat - PT 1 / 1 Bedrock IT 7! Cloy - CL ----- G roundwater Flow Direction KSHCO DEL CHCCXEO K DAVIS APMKNCDfDESIGN) N^RWEEKCONSIRUC'IWI CROSS-SECTION D -D ' C orporate Rem ediation Group An Alliance between DuPont and URS Diamond B a rle y Mill Ploza, B u ild in g 27 W ilmington, Delowore 19805 D uPont W ashington Works Main P lont W ashington, W est V irg in ia T7 0 0 0 16 6 North E 630-- 1 o'; P ..P ' , ' , o'', . , d '. I p . o ; 'o ' _ -0 | <\ . ; o \ ! . ;o",CL ; o '.: ,o .O o'.CF ;o,o: :o\o: ;o".! ;d,0! :o ;:r: ; o v ,o '. o ' QUATERNARY ALLUVIUM 0 540- . -, o - . . r . . o - . H ;.. , o . ~ o , o o u . , o ~ . o ^ , o , . , o . . 0 G . , . 0 ' , ; ' o ' . o ; ' o . o : ' o " , ; o p . o : ' 'o '`c l 'o ' . o ; o \ ; ' o ' . o : : ' 'r i :ci ' ' -'-s:'.-' 9 ' ' 9 '. - : - ' : ; 9 ' . - 'a 'J 9 ,o o o ' [ : 1 Q -: ' : q 1 ; - o o ' 'o :^ ' o ' ; " 530 120 FT Topsoil - 0L f = | Fill irrm -1 1 Sand - SM.SC.SP s u t ml I P : ) b a n d and Gravel -- SW,GP,GW,GM LEGEND: g g ] P e at - PT 1 / \ Bedrock \Z2 Clav - a yj _______ ------------ S ta tic W ater Level, Dec. 1991 A p pro xim ate Geologic C ontact S ta tic W ater Level, Inferred ------- G ro u n d w a te r Flow D ire c tio n 0CSIGNC0 " Of1 CKME0 K. D4VIS APHWMIXWSiCN) if>ORCJVED(CONSrBUCnoH) <SIQil> 4V C orporate Rem ediation Group An Alliance between DuPont and VRS Diamond B a rle y Mill Plaza, B u ild in g 27 W ilm ington, O elow are 19 80 5 CROSS-SECTION E -E ' DuPont Washington Works Main Plant Washington, West Virginia KMX IMI J&6 ni . JnMC Mhon ' 1/24/01 7*22*005 3.15 0 0 0 16 7 89T000 E A S T AJ06-M W 02 F' ELEVATION (feet MSL) SCA 400 0 VERTICAL SCALE: 400' =15' |T|T]Tj^ Topsoil -- 0L S3 Em f 1 Sand - SM.SC.SP ru n a i t - m l IP : 1 Sand and Gravel -- SW.GP.GW.GM LEGEND: Q Peat - PT f Z \ Bedrock \Z 2 c i" y - cl y j S tatic Water Level, Dec. 1991 _______Approximate Geologic C ontact ----------- Static Water Level, Inferred ---------- Groundwater Flow Direction APPOOVCDCDCSiCM) APPHOWEO(C0"StUCTlON) C orporate Rem eriatlon Group An AUianct to h v ttn DuPont and UBS D iamond 8 o rle y Mill ploza. B u ild in g 27 W ilm inqton Deloworc 19805 DuPont Washington Works Main Plant Washington, West Virginia F^MWT -F. G -Q04--SB3- R 04-M W 02 S04-^SB02 iD SCALE & S05-M W 02 200 200' CMCM OO OHIO RIVER (NORMAL POOL ELEVATI0N=582.0') _S. cinlS G1 630 614 598 582 566 -> LEGEND: HOLOCENE OVERBANK DEPOSITS SILT AND CLAY h PLEISTOCENE GLACIAL OUTWASH DEPOSITS COARSE SAND AND GRAVEL HORIZONTAL SCALE: 1" = 4 0 ' VERTICAL SCALE: 1" = 2 0 ' A iM A Corporato Romodation Group A n AUiUmo* betaw en D uPont and UHS D iam ond Barley MM Plaza, Building 27 Wilmington, Delaware 19805 SECTION G - G ' D uPont W ashington W orks W ashington, W est V irginia SCALE A * shown DATE 9 /4 /0 2 DESIGNED CHECKED KLO DRAWN DEL APPROVED 000169 CAD FILE NO. 36358001 FIGURE 3 .1 7 LEGEND , DOft-MWOI = MONITORING WELL J17-PW01 <J- = PRODUCTION WELL ----------- w- = APPROXIMATE GROUNDWATER FLOW DIRECTION ------------- = GROUNDWATER ELEVATION CONTOUR SCALE 700 0 700' te a o m u no CM* oa OCDOD IP S IM M lfC a M A94 iv*Mjwii<Lummui:now) mm Corporate Remediation Groip An Alliance between DuPont an d UPS D iamond B a rley Mill P laza, B u ild in g 27 W ilminQton, D elaw are 19 80 5 REVISED - FEBRUARY 2002 GROUNDWATER ELEVATION MAP DuPont Washington Works Main Plant Washington, West Virginia A* Mem j 12/11/02 j FEB2002 j 3 .1 ft 0 0 0 17 0  <<I Cem /7 1y ' / ^^ 0 e j v EB PROPERTY LINE ne S o urce: USGS L ittle M ocking, Ohio - W est V irginia Q uadrangle Ml Corporate Remediation Group An Alliance between DuPont and URS Diamond B a rle y Mill Plaza. B u ilding 27 W ilm ington, Delaware 19805 SITE LOCATION MAP Local Landfill W ashington, W est V irginia MLE Net to m ie MI 9/27/01 ""T o. cnuim U. HOUUMY " " oa mmmb fiM U Ift 7421 0 1 noue 4 .0 U CC171 cT ooa it 000175 B NORTH 850- 825- 800 -- 775 -- Ld Ld 750- < 7 2 5 --1 Ld 700- 675- 650- 625- LLM W -4 LEGEND SHALE SANDSTONE PROJECTED LOCATION OF LANDFILL LLM W -8 B' SOUTH 850 -- 825 -- 800 -- 775 -- 750 725 700 675 650 625 CLAY, WEATHERED SHALE AND WEATHERED SANDSTONE SCREENED INTERVAL SCALE STATIC WATER LEVEL OCTOBER 2002 200 0 200' 8 X VERTICAL EXAGGERATION ***** w rite- O X ENOUSH PJC IM S WCAtKCCWIWUCTPM) C o rpo rata R am adM Ion f t o i p in jlH w n M aw DttPtmi and O SS Dia m i Sortay MM Plaza, B u M n g 27 GEOLOGICAL CROSS-SECTION B -B ` Locol Landfill Washington, West Virginia to A j n/tv*Di JTM7431H03 1TM"* 4,4 C WEST 850-i 800 750 700 LLMW 6 600- 000176 500 J LEGEND SHALE SILT SANDSTONE AND SILTSTONE CLAY, WEATHERED SHALE AND WEATHERED m SANDSTONE SCREENED INTERVAL STATIC WATER LEVEL I OCTOBER 2002 LLMW 4 C' EAST 850 -8 0 0 750 700 i )O2- 650 ^ 600 -5 5 0 500 300 q C. A i T 0 -- a-- w mu GEOLOGICAL CROSS-SECTION C -C ' OB. KU> 3 0 0 ' HWWgBD C orporate Rem edation Group n Allianet h hM DuPont and URS Diamond Washington, West Virginia VERTICAL E X A G G E R A T IO N : 6 X B o rle y Mill Plaza. B u ild in g 2 7 W ilm ington. Delaware t9 8 0 5 ~ ~ r r= ^ r 2000 2000 J W. V A ( rj SPURGE' NEV HAVEN, VV-Q HIO QUADRANGLE 7.5' SERIES <o?> ^ Corporate Remediation Group An Alliance between DuPont and The W-C Diamond Croup B a rle y Mill Plaza, B u ilding 27 W ilm ington, Delaware 19880-- 0 02 7 SITE LOCATION MAP SCttJE M IC 1 2 /2 1 /9 _etart La nd fill Site Letart, WV TM n-- TDL CNCCKXD m uM 0EL C M F IX HO. 72SMX MUN ---- 5 .0 LEGEND: 0.05-1.0 ug/L <0.05 mg/L SCALE 000180 Mm---------- <*O D> Corporato RwiMMMlOfi Qnwp f>TM Ml n I M M M n ua Mm. >7 C - 8 IN GROUNDWATl Latori Landfll Uteri. Waal VlrqMo im m | t/n/ta | uhobi I J TgTOO i I ? *i i LEGEND: A SURFACE WATER SAMPLE LOCATION SCALE 650 0 650' SOURCE HAP TAKEN FROH TW USCS NEW HAVEN. WV 7.5* SERES QUADRANGLE <m s> 6 xz Corporate Remediation Group An Alliance between DuPont a nd URS Diamond B a rley Mill P la zo, B u ilding 27 W ilm ington, Delaware 19805 RT. 33 STREAM AND BRINKER'S RUN SURFACE WATER SAMPLING LOCATIONS L e ta rt Landfill Site L e ta rt, W est V irginia $CAL As shown OATE 11 /2 5/0 2 I DESIGNED CHECKED ORAWN DEL APPRCMD CAO n ix NO. 7420A019 neu 5.3 LEGEND: OHIO RIVER WATER SAMPLING LOCATION, (DIP AND MID-COLUMN SAMPLES) SCALE 650 0 650' aOUMt: KM TAKDt FROM THE UBO WEW HAW K WV 7 S 3PW 3 QUACEAHCtE Corporate Remediation Group An Alliance between DuPont and UPS Diamond B a rle y Mill Plozo, B u ilding 27 W ilm ington, Delaware 19805 OHIO RIVER WATER SAMPLING LOCATIONS L etart Landfill Site L etart, W est Virginia SCALE Aa shown DATE 1/ 3 0 / 0 2 OCSIGNCD DKAWM OEL CHECKED APPOvD TDL UOOJ.&3 CM) FILE NO. 7420A01& ncuoc 5 .4 frSTOOO 95T0OO North C 800780760- 740720700680660640620600580- 560540540- LEGEND: I SCREENED INTERVAL SANDSTONE AND SILTSTONE r~7 GROUNDWATER ELEVATION (OCTOBER, 2002) SHALE D /E AQUIFER ZONE NOTE: Surface soils are not shown as a separate geologic unit. SCALE 200 0 200' VERTICAL EXAGGERATION O f 5 X South C' - 800 - 780 - 760 - 740 - 720 - 700 - 680 - 660 - 640 - 620 - 600 - 580 - 560 - 540 - - 540 C orporate RemedtaBon Group A n A lliance b ttive en D uP ont a n d U PS D iam ond GEOLOGIC CROSS-SECTION C - C ` Leta rt Landfill Site Letort, West Virginia Barley Mill Plozo. B u ild in g 27 _________ W ilm ington, D eloo re 19 80 5__________ T%7 i . 1 J i 83T0OO LEGEND; LMW-8 A ZONE MONITOR WELL -$ LMW--3 C ZONE MONITOR WELL ^.LMW-4 D/E ZONE MONITOR WELL - luw-2 a F ZONE MONITOR WELL <$- LMW- 9 UNDER F ZONE MONITOR WELL ........... GROUND WATER CONTOUR UNE ........ 9m GENERALIZEDGROUND WATERFLOWQtRECHON H > C orporata Ram adlatlon Group <tn jtiltanc* batuaan D yiPont a n d UJS D iam ond florlay Mill Plazo, Building 27 D /E -- ZONE GROUNDWATER CONTOUR MAP - 4Q 02 Letort Landifll Site Letart, West Virginia T i e * ,I"r r " '" " T u "'' "ee. ""U S ati TM "mo 63T0OO Source: MAP TAKEN FROM THE LUBECK, W USGS QUADRANGLE 1200 SCALE 1200' 2400' K.EMMS NTM5 DO. aati tr nm tr rm ri i) mnofeowraucnotQ 4V SITE LOCATION MAP C orporate Rem ediation Group j4n 4 tance between Chipant and URS th am ond D ry Run L ondfill L ubeck, W est V irg in ia B o rley Mill Plo?o, B u ild in g 2 7 W ilm irqton, D elato re 19805 U |M MUM * MA j 11/V0I I 74XBBBS j 6.0 LEGEND: 0.05-1.0 ug/L <0.05 ug/L SCALE ooog --- -----------ittta---------m. Corporate R tm d M o n O M p M M m* S U I------- MWrwtovUUfS>>.MOo M M m * i 2? IMO C - 8 IN GROUNDWAT Dry Run LandM Lufcsrft, W**t Virginia M mmm1 i / M ( M M ) | O Z GXOQ C6TOOO WGTOOO 96T 000 000197 fiCTOOO APPENDIX A APPENDIX A BORING LOGS AND WELL CONSTRUCTION DIAGRAMS WASHINGTON WORKS FACILITY 000201 000202 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Main Plant Project# 18983635.40000 Date Started Date Completed Well Diameter Drilling Method Company AJ06-MW02 July 10, 2002 July 12, 2002 2" Rotosonic Bowser Momer (page 2 of 6) Sampling Method Northing (WV St PI) Easting Coord. Survey By Logged By Continous 464393.33 2238081.33 Vernon L. Tilton, G. Donahue a<u) Surf. Elev. aaa). 25- O X <CL O SAND- (cont). DESCRIPTION Well: AJ06-MW-02 Elev.: 635.55' 30- 3540- Tannish SAND with fine to coarse gravel, dry to moist. -PVC ' -- Grout ^Dark brown to blakc CHARCOAL layer. Tannish SAND with fine to coarse GRAVEL, dry to moist. 45- .Tannish SAND with layering of dark brown CHARCOAL beds, fine to \coarse gravel, dry to moist._______________________________________ j Tannish SAND with fine to coarse gravel, dry at top. Coarser in bottom 5 0 - 2.5', with random spaced charcoal, wet. 000203 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Main Plant Project# 18983635.40000 Date Started Date Completed Well Diameter Drilling Method Company AJ06-MW02 July 10. 2002 July 12, 2002 2" Rotosonic Bowser Momer (page 3 of 6) Sampling Method Northing (VW St PI) Easting Coord. Survey By Logged By Continous 464393.33 2238081.33 Vernon L. Tilton, G. Donahue <v Surf. . Elev. OD(U. 50- O X Q. Otl DESCRIPTION Well: AJ06-MW-02 Elev.: 635.55' Tannish loose SAND with little fine to coarse gravel, dry to moist. 55- 60- Tannish SAND with some fine to coarse gravel, grain size of sand varies from from fine to coarser. Moist at very top and wet with depth. -PVC -Grout 65- 70- 75- 000204 DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Main Plant Project U 18983635.40000 Date Started Date Completed Well Diameter Drilling Method Company July 10. 2002 July 12. 2002 2* Rotosonic ; Bowser Momer Surf Elev. -*Ts DESCRIPTION Fine tannish SAND with little fine to coarse gravel, wel. AJ06-MW02 Sampling Method Northing (W V St PI) Easting Coord Survey By Logged By (page 4 of 6) Continous 4 6 4 3 9 3 .3 3 2236081.33 Vernon L. Tilton. G. Donahue Well: AJ06-MW-02 Elev.: 635.55' SAA- SAND, but with little organics. Reddish-tan fine grained SAND with little fine to coarse gravel, wel Tannish fine lo medium SAND with trace fine to coarse gravel, wet. By 93', greyish tan medium to coarse SAND with trace fine to coarse gravel, wet Hit bedrock at -95' Light gray sandy SILTSTONE, dark gray micaceous, competent BX. Dry. - Grout 000205 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Main Plant Project # 18983635.40000 Date Started Date Completed Well Diameter Drilling Method Company AJ06-MW02 July 10, 2002 July 12, 2002 2' Rotosonic Bowser Momer (page 5 of 6) Sampling Method Northing (WV St PI) Easting Coord. Survey By Logged By : Continous : 464393.33 : 2238081.33 : Vernon : L. Tilton, G. Donahue Surf. . c Elev. oQ<U. 100- O X Q<ao.. DESCRIPTION Well: AJ06-MW-02 Elev.: 635.55' 105110- Light gray clayey fracture zone, dry, trace micaceous. Light gray medium to coarse silty SANDSTONE, micaceous, moist. Light gray clayey SANDSTONE, medium to coarse, micaceous, moist. Light to slightly darker gray clayey SILTSTONE, wet, fractured, micaceous. Light gray silty SANDSTONE, dry, very micaceous. Coarse gravelly light gray CLAY, micaceous. Light gray silty SANDSTONE, micaceous, fractured. - -- Grout 5-P V C Bentonite 115120125- Light gray SANDSTONE, medium to coarse, micaceous, dry to moist. Light gray sandy SILTSTONE, layered light and dark gray beds, micaceous, dry. Light gray medium grained SANDSTONE, dry. :FW" Light gray coarse-grained SANDSTONE, micaceous, dry to moist. Light gray, fine to medium grained SHALE, dry, some dark gray color, \micaceous.____________________________________________________ U U 0206 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Main Plant Project # 18983635.40000 Date Started Date Completed Well Diameter Drilling Method Company AJ06-MW02 July 10, 2002 July 12,2002 2" Rotosonic Bowser Momer (page 6 of 6) Sampling Method Northing (WV St PI) Easting Coord. Survey By Logged By Continous 464393.33 2238081.33 Vernon L. Tilton, G. Donahue a<>u cu_ Surf. Elev. Q. aCD 125- 130- O Well: AJ06-MW-02 X Elev.: 635.55' DESCRIPTION e> Lt gray, medium to coarse silty SANDSTONE, dry. Screen Lt gray fine to medium SILTSTONE, micaceous, dry. Lt gray fine grained SILTSTONE, micaceous, dry, some brownish gray s,color streaks. _________ ___________________________________ J Gray, clayey SHALE, fractured, wet. Light gray, red and green clayey SHALE, moist to wet, slickensides, some yellow found, mottling. CO CT) Sand Slump 135- TD hole at 134'. Next day, TD was 128.5' (slumpage?). 140- 145- s^ v 150- 1)00207 00020S 000209 000^10 m URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-12 August 12, 2002 August 13,2002 4" Air coring Continuous (page 1 of 5) Company Northing (WV St PI) Easting Coord Survey By Logged By Duncan Bros 696125.515' 1735234.766' Vernon Lucinda Tilton 0) Surf. Elev. Ooa). 740.12 - 740 O X Q. DESCRIPTION 2o Casing set at 14'. Reddish brown clayey SHALE at - 1' Well: LMW-12 Elev.: 742.62' 5 - , 735 10- , 730 1 5 -, 725 20- 720 25- -PVC Greenish gray and greenish brown SHALE, fractured, orange mottling and orange/rust colored thin beds, dry to wet. Greenish gray fine grained SANDSTONE, with dark grey thin layering, micaceous, trace shale, dry. : -- Grout Greenish gray and orange brown fine SANDSTONE, micaceous, orange mottling, dark gray thin layering, little shale, dry. Orange brown, fine to coarse SANDSTONE, coarsening downward, orange mottling, micaceous, moist to wet. Orange brown medium to coarse SANDSTONE, micaceous, orange mottling, m oist.1 0 0 0 211 ,s\Drill logs for Summer 2002\LMW-12.bor 01-15*2003 l:\Vi URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project # 18983632.00015 Dale Started Date Completed Well Diameter Drilling Method Sampling Method : August 12, 2002 : August 13,2002 : 4" : Air coring : Continuous LMW-12 (page 2 of 5) Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 696125.515' 1735234.766' Vernon Lucinda Tilton Surf. Elev. QQ . CD 740.12 25- 715 3 0 - 710 O X <CL ODC DESCRIPTION Well: LMW-12 0>) Elev.: 742.62' a80) Orangish brown and greenish gray medium to coarse SANDSTONE, micaceous, some quartz crystals, moist to wet. Orange brown medium to coarse SANDSTONE, micaceous, orange mottling, large mica, some quartz crystals, moist to wet. s\Drill Jogs for Summer 2002\LMW-12.bor 35- 705 40 -- - 700 45 -- 695 50- -PVC Orange brown and greenish gray coarse grained SANDSTONE, micaceous, very mottled orange/rust colored, moist to wet. Greenish gray medium to coarse SANDSTONE, micaceous, with trace green shale, dark grey thin layers, dry to moist, little orange mottling. Greenish gray medium grained SANDSTONE, and greenish gray SHALE mixed together, fractured, micaceous, dry to moist. Dark reddish brown SHALE and some gray SHALE, slickensides, very fractured, wet. Greenish gray SHALE, very little red SHALE, little slickensides, very fractured, wet. Greenish gray fine sandy SILTSTONE, micaceous, dry to moist with thin dark gray layering, some greenish gray shale from 48.5 to 56.6'. ' -- Grout 0 0 0 2 12 01-15-2003 l;\\A UPS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project # 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-12 August 12. 2002 August 13.2002 4" Air coring Continuous (page 3 of 5) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 696125.515' : 1735234.766' : Vernon : Lucinda Tilton <<iv> cLu sz Surf. Elev. a<u. 740.12 O 50- 690 g i (Q<a3d. DESCRIPTION Well: LMW-12 aOS<>C0dD)J' Elev.: 742.62' 55- - 685 60- 680 6 5 - 675 Greenish gray SHALE, dry, very competent. Greenish gray fiend sandy SILTSTONE, micaceous, with thin dark gray layering, dry. Greenish gray and reddish brown SHALE, dry. Brown shale and slicks from 162-164'. Greenish gray sandy SHALE, slickensides, dry. -PVC -Grout 01-l5-2Q03TtW .>s\Driil logs for Summer 2002\LMW-12.bor 70- - 670 75- 0 0 0 2 13 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method : August 12, 2002 : August 13,2002 : 4" : Air coring : Continuous LMW-12 (page 4 of 5) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 696125.515' : 1735234.766' : Vernon : Lucinda Tilton L00Ci- Surf. Elev. 0 740.12 o O X <cc e> DESCRIPTION 75- - 665 Sandy SHALE (cont.). Well: LMW-12 Elev.: 742.62' -Grout -PVC 80- 660 Bentonite 01-15-2003 l:\W .s\Drill logs for Summer 2002\LMW-12,bor 8 5 - 655 9 0 - , 650 9 5 - . 645 100- Greenish gray SHALE, slickensides, sandy, competent, dry. Greenish gray fine grained sandy SILTSTONE, dry. Greenish gray fine to medium sandy SILTSTONE, micaceous, dark gray, thin layers, dry. Greenish gray, fine to medium SANDSTONE, micaceous, dark thin gray layers, dry, competent. - Screen -Sand Greenish gray medium to coarse SANDSTONE, micaceous, dry, competent._______________________________________________ Greenish gray fine to medium SANDSTONE, micaceous, thin dark gray layers, dry, competent. Grenish gray medium to coarse SANDSTONE with trace green/gray SHALE, micaceous, trace reddish staining, dry to moist, competent. 0 0 0 2 14 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method August 12, 2002 August 13,2002 4" Air coring Continuous LMW-12 (page 5 of 5) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros . 696125.515' : 1735234.766' : Vernon : Lucinda Tilton L<CLDD C Surf. Elev. 0> 740.12 o O XCL <O' o DESCRIPTION 100- 640 Greenish gray SANDSTONE (cont.). Well: LMW-12 2a>>2 Elev.: 742.62' C8<Dt - Screen -Sand 105- 635 Greenish gray, clayey SHALE, slickensides, wet. Greenish gray SHALE, less clayey, very fractured, slickensides, wet. Reddish brown, bright red and greenish gray SHALE, very fractured, yellow brown and purple mottling abundant, slickensides, wet. 110- 630 Greenish gray SHALE, slickensides, moist. Greenish gray fine grained sandy SILTSTONE, micaceous, dry. -Slump? 115- 625 120- 620 TD hole at 119' bgs. s\Dri!) logs for Summer 2002\LMW-12.bor 01-15-2003 l:\Vi 125- 0 0 0 2 15 1)0 0 2 16 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Main Plant Project # 18983635.40000 Date Started Date Completed Well Diameter Drilling Method Sampling Method Y14-MW-02 August 18, 2002 August 22, 2002 2" Rotosonic Continous Coring (page 2 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By Bowser Momer 463896.38' 2233587.79' Vernon Lucinda Tilton Surf. . Elev. OQa). 25- O X 0- o DESCRIPTION Well: Y14-MW-02 Elev.: 643.12' 30Brown, finge grained SAND w/ some gravel, moist. 35- 40- -PVC - -- Grout 45- Mii 50- 4 )0 0 2 1 7 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Main Plant Project # 18983635.40000 Date Started Date Completed Well Diameter Drilling Method Sampling Method Y14-MW-02 : August 18, 2002 . August 22, 2002 : 2" : Rotosonic : Continous Coring (page 3 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By Bowser Momer 463896.38' 2233587.79' Vernon Lucinda Tilton a0>) Surf. Elev. OQa>. 50- O X a<. ao: DESCRIPTION Well: Y14-MW-02 Elev.: 643.12' 55- 60- Brown fine to medium, fairly clean SAND w/ trace gravel, moist, 1" layer of charcoal. -PVC -Grout 65- 70- Greyish-brown fine grained SAND with trace gravel, very moist. 3' of 10' recovery. 75- 4)00218 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Main Plant Project # 18983635.40000 Date Started Date Completed Well Diameter Drilling Method Sampling Method Y14-MW-02 August 18, 2002 August 22, 2002 2" Rotosonic Continous Coring (page 4 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By Bowser Momer 463896.38' 2233587.79' Vernon Lucinda Tilton Surf. Elev. C<uL Q 75- O X CL O(5 DESCRIPTION Well: Y14-MW-02 Elev.: 643.12' 80- Greyish brown SILTSTONE with mica flecks. Dark brown fine to medium SAND w/ trace gravel, moist. At 92 feet have brown very fine grained SAND. At 93-94 feet, greyish brown medium grained SAND with some gravel. 94-94' Brown very fine grained SAND, moist. 95-100 feet, Greyish brown, medium grained 85- SAND w/ some gravel, moist. -PVC - Grout 90- 95- 100- 0 0 0 2 19 DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Main Plant Project # 18983635.40000 Date Started Date Completed Well Diameter Drilling Method Sampling Method Y 14-MW-02 : August 18, 2002 : August 22, 2002 : 2" : Rotosonic : Continous Coring (page 5 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Bowser Momer : 463896.38' : 2233587.79' : Vernon : Lucinda Tilton Well: Y14-MW-02 105- 110- ^ 115- 120- 125- Greenish grey clayey SILT w/ greenish grey fine grained gravel, dry. Greyish green fine grained SANDSTONE. Brown silty CLAY with weathered fragments of greyish green fine \grained sandstone throughout, WET._________________________ Greyish green fine grained SANDSTONE. -Grout -PVC Reddish brown CLAY w/ sand, gravel and weathered green shale fragments, WET. Bentonite seal Greyish green fine to medium grained SANDSTONE, very micaceous. -- Sand pack Well Screen D00220 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Main Plant Project # 18983635.40000 Date Started Date Completed Well Diameter Drilling Method Sampling Method Y14-MW-02 August 18, 2002 August 22, 2002 2` Rotosonlc Contlnous Coring (page 6 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Bowser Momer : 463896.38' : 2233587.79' : Vernon : Lucinda Tilton Surf. Elev. o. CD O 125- O X 0<DOC DESCRIPTION Well: Y14-MW-02 <>u> Elev.: 643.12' o80c) 130135140- Greyish green medium grained SANDSTONE, slightly micaceous. Greyish greeen SILTSTONE, highly eathered with 3" single red/brown clay lens, WET. Grey very fine grained SANDSTONE, highly weathered w/ greyish green clay lenses. TD @ -139'. -Sand pack -W ell Screen -Slump? 145- 150- 000221 APPENDIX B 222000 APPENDIX B BORING LOGS AND WELL CONSTRUCTION DIAGRAMS - LOCAL LANDFILL 000223 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project # 18983633.00014 LLMW-11B/A Date Started Date Completed Well Diameter Drilling Method Sampling Method July 16, 2002 July 17,2002 4"(B), 2"(A) Air Coring Continuous Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 460410.087' 2235851.693' Vernon Lucinda Tilton <<uu Surf Elev. Q. oCD Well: LLMW-11B O Elev.: 665.115' DESCRIPTION Tannish brown, silty CLAY with some organics, gray/orange mottling throughout, dry. *** W ell LLMW -11A set from 22-42' bgs with sand from 19-42', bentonite from 17-19', and grout to surface. Coordinates 460413.301 N, 2235832.769E, TOC @ 663.825'. 1015- 20- 25- Tannish brown, silty CLAY, grey and orange mottling, dry and turning moist at 15.4' -PVC - Grout Tannish brown, silty CLAY with some gray orange mottling, moist Grey silty CLAY with fine to course gravel, moist, orange mottling - Screen (A) 000224 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project # 18983633.00014 LLMW-11B/A Date Started Date Completed Well Diameter Drilling Method Sampling Method July 16, 2002 July 17, 2002 4"(B). 2"(A) Air Coring Continuous Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 460410.087' 2235851.693' Vernon Lucinda Tilton Surf. Elev. Q. oCD 25- o QX- CD DESCRIPTION Well: LLMW-11B <>u Elev.: 665.115' aou0). 3035- - f - i - j -i i 1 1 1 1 1 1 Gray clayey SILT with some fine to coarse gravel and sand, moist to ! ! S I ! ! I / I S' wet, orange mottling, gravel includes weathered micaceous green to - f'- f f S-- grey fine grain sandstone ! I I! 1! !I I !! I! rI !l - lI II I filili- ! i I I ! I ! f-f I "i i i i f i i r 4 - i -s i I!!!II!i SI I I I !I II Grey clayey SILT, moist II i 1! I ! I I ! IS Grey silty fine to medium SAND with little clay, moist I I ! ! I I I ! Grey clayey SILT with some fine to course gravel and sand, moist IIII IIl !I !I h-f - f - l i ! I I ! I IIIII!II!i !! - f - f - f - f + ! ! I ! I ! ! S ! ! ! S! 1I I S i I ! I ! i-f-i Grey to olive green silty CLAY, tan fine to course gravel and sand, moist Grey silty CLAY grading to weathered SHALE. Moist. 40Grey to tannish brown weathered SHALE breccia, dry, becomes more competent with depth. Set 6" casing to 49'. - Screen (A) -Grout 45-PVC Fine to medium greenish gray SANDSTONE, micaceous, thin bedding 50- fla y e r s of light and dark grey, dry.__________________ 000225 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project# 18983633.00014 LLMW-11B/A Date Started Date Completed Well Diameter Drilling Method Sampling Method July 16, 2002 July 17. 2002 4*(B), 2"<A) Air Coring Continuous Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 460410.087' . 2235851.693' : Vernon : Lucinda Tilton u<0_D) Surf. Elev. QQ>. Q 50- O 0X. 2o DESCRIPTION Well: LLMW-11B Elev.: 665.115' 55- 60- Greenish gray sandy SILTSTONE, fine grained light and dark thin layering, trace mica, slickensides, moist. Little fractures from 65.5-72'. Some mica grains, grading fine to medium and a couple small dark gray beds of shale in this interval. - Grout -PVC 65- 70- Greenish grey SHALE, some fracturing, moist to wet. Greenish gray sandy SILTSTONE, fine to medium, light and dark layering, micaceous, slickensides, moist. 75- 000226 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project# 18983633.00014 LLMW-11B/A Dale Started Date Completed Well Diameter Drilling Method Sampling Method July 16. 2002 July 17,2002 4"(B), 2"(A) Air Coring Continuous Company Northing (W V St PI) Easting Coord. Survey By Logged By : Duncan Bros : 460410.087' : 2235851.693' : Vernon : Lucinda Tilton Q. QCD 75- Surf. Elev. O X CL 2 DESCRIPTION Well: LLMW-11B <>D> Elev.: 665.115' 8 aC:D 80859095- 100- Greenish gray fine clayey SILTSTONE, trace shale, fractured, moist to wet. Medium sized layers of dark grey to black, grading from clayey SILTSTONE to clayey SHALE, micaceous. Black crumbly COAL (organic material) dry. Greenish gray fine to medium silty SANDSTONE, little organics present, micaceous, slickensides, dry. Greenish gray, fine to medium silty SANDSTONE, micaceous, dry to moist. SANDSTONE, with small bands of dark grey and tan, trace fracturing. Dark gray SHALE, slickensides, organic layering, fractured, moist to wet. Greenish gray, clayey SHALE, micaceous, slickensides, fractured, grain size coarsening from fine to medium downward. Greenish gray medium grained SANDSTONE, micaceous, red mottling, dry to moist. SANDSTONE with grains coarsening medium to coarse, moist to wet. -Grout -PVC -- Bentonite Seal -Sand Pack -Screen (B) 000227 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project # 18983633.00014 LLMW-11B/A Date Started Date Completed Well Diameter Drilling Method Sampling Method July 16,2002 July 17,2002 4-(B), 2"(A) Air Coring Continuous Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 460410.087' : 2235851.693' : Vernon : Lucinda Tilton <(0D LL Surf. a. Elev. Oa) 100- O X C<te>rL DESCRIPTION Well: LLMW-11B a>> Elev.: 665.115' 8<U CL 105110-- Greenish gray clayey SHALE, slickensides, fractured, moist to wet. Greenish gray medium grained SANDSTONE, micaceous, red mottling, moist. SANDSTONE, grains coarsening from medium to coarse, some light to dark thin layering. -- Sand Pack -Screen (B) 115- Greenish gray sandy SILTSTONE, micaceous, moist. Greenish gray SHALE, with some brownish red shale and dark gray shale, moist to wet. TD hole @ 116'. 120- 125- 000228 000223 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project # 18983633.00014 Date Started Date Completed Well Diameter Drilling Method Sampling Method LLMW-12B : July 11.2002 : July 11.2002 : 4" : Rotosonic : Continuous sampling (page 2 of 4) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Bowser Momer : 460761.829' : 2238021.491' : Vernon : Steve Opp Surf. Elev. Q. <u Q 25- 0 1 Q_ 2o DESCRIPTION Well: LLMW-12B Elev.: 764.280' Reddish brown silty SHALE, moderatley weathered, highly fractured, slickensides present, dry. Greenish grey, silty, fine-grained SANDSTONE, very competent, 30- alternating very thin beds of light and dark grains starting at 6.1' depth. Dark beds are micaceous, dry. 35-Grout -PVC SAA, SANDSTONE becomes fine-to-medium-grained at 5.3', cross-bedding @ 6.T. dry. 40- 45- Reddish-brown, silty SHALE, fissile, dry. Highly fractured starting at 49' bgs, with slickensides, green mottling prevalent. 50- 0 00 2 .30 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project # 18983633.00014 Date Started Date Completed Well Diameter Drilling Method Sampling Method LLMW-12B July 11, 2002 July 11, 2002 4" Rotosonic Continuous sampling (page 3 of 4) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Bowser Momer : 460761.829' : 2238021.491' : Vemon : Steve Opp Surf. Elev. 0) Q 50- O X Q. O DESCRIPTION Well: LLMW-12B Elev.: 764.280' 55 -Grout 60-PVC 65- Greenish-grey, silty, fine grained SANDSTONE, competent, micaceous, very thin light and dark bands, dry. Becomes fine to medium grained Bentonite Seal and competent with white quartz veins throughout core between 76.5' and 84.2'. 6" fracture zone at 84.5', filled with reddish day, very soft, 70- iron staining near and throughout fracture zone, moist. Sand Pack 75- 000201 000232 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project# 18983633.00014 Date Started Date Completed Well Diameter Drilling Method Sampling Method LLMW-13B July 15, 2002? July 16, 2002 4" Air Coring Continuous (page 1 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 462147.898' : 2237960.343' : Vernon : Lucinda Tilton o<ur Surf. Elev. Q. QIP 0- o X0. DESCRIPTION 3o Casing installed to 9'. Bedrock hit at 4.5'. Well: LLMW-13B > >ID Elev.: 8a> DC 5 - Bedrock encountered. SHALE? Not ID'd in field book. Reddish SHALE, slickensides, yellow mottling, moist 10- Green and red SHALES, mostly green, slickensides, yellow and orange mottling, moist to wet. Grout PVC Green SHALE, orange and red mottling, moist to wet. 20- Green fine to medium SANDSTONE, micaceous, moist. Green SHALE with orange mottling, moist._____________________ 2 5 - 'Green SANDSTONE, fine to medium with dark grey orange layers. 000233 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project# 18983633.00014 Date Started Date Completed Well Diameter Drilling Method Sampling Method LLMW-13B July 15, 2002? July 16, 2002 4" Air Coring Continuous (page 2 of 6) Company Northing (W V St PI) Easting Coord. Survey By Logged By Duncan Bros 462147.898' 2237960.343' Vernon Lucinda Tilton <OD) Surf. Elev. Q<CDL 25- 30- y X Q. o3 DESCRIPTION Well: LLMW-13B <OO>D Elev.: oCD: micaceous, moist. Dark green grey SANDSTONE, micaceous, moist. Green SANDSTONE, fine to medium, with dark grey layering and orange mottling, micaceous, moist. Greenish grey SANDSTONE, fine to medium, micaceous, some red and orange mottling, dry to moist.______________________________________ Greenish SILTSTONE, micaceous, some orange and red mottling (rust colored). Grey and red SILTSTONE, little reddish mottling, weathering, moist to wet. Slickensides in bottom 1'. 35- Red SHALE, with some grey SHALE. Some yellow mottling, with an abundance of slickensides. -Grout -PVC 40- 45SAA but less gray shale and more weathered 50- 000234 URS DuPont Corporate Remediation Group Washington Works Consent Order W ell Installation Local Landfill Project# 18983633.00014 Date Started Date Completed Well Diameter Drilling Method Sampling Method LLMW-13B July 15,2002? July 16, 2002 4" Air Coring Continuous (page 3 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 462147.898' : 2237960.343' : Vernon : Lucinda Tilton Surf. Qao>. Elev. 50- 0 1 Q_ 2o DESCRIPTION Well: LLMW-13B c0>)h Elev.: 8<D C 5560657075- ! Greenish gray fine to coarse SANDSTONE, micaceous, trace reddish ; mottling, dry to moist.___________________________________________ : Red SHALE with some gray, yellow mottling, slickensides, moist to wet. Red SHALE mixed with grey SANDSTONE, trace micaceous, ; slickensides, moist. Red SHALE, with some grey shale, yellow mottling, slickensides, moist to wet.________________________________________________________ Fine to medium greenish grey SANDSTONE, micaceous, trace grey shale, dry to moist. ioni Red SHALE with some grey, slickensides, moist to wet. Greenish grey SANDSTONE, fine to medium with some red shale, moist. Red SHALE with some grey shale, moist to wet, slickensides 74-75.5'. cOo) Grout PVC V00235 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project# 18983633.00014 Date Started Date Completed Well Diameter Drilling Method Sampling Method LLMW-13B July 15. 2002? July 16,2002 4" Air Coring Continuous (page 4 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 462147.898' : 2237960.343' : Vernon : Lucinda Tilton LaacL>t Surf. Elev. aQ<L>. 75- 0 Well: LLMW-13B 1 CL <aO: DESCRIPTION O<>OOaL>D Elev.: Greenish gray SHALE, with some gray SANDSTONE, fine grained, trace micaceous, red mottling, moist. Red SHALE with little grey SANDSTONE, slickensides, moist. 80- 859095100- Red SHALE, trace grey shale, slickensides, moist to wet. Premdominantly red SHALE mixed with grey SANDSTONE, fine grained, mocaceous, dry to moist. Fine to medium greenish grey SANDSTONE mixed with grey and red SHALE, micaceous, dry to moist. -Grout -PVC Grey SHALE, some red shale and trace SANDSTONE, moist. Red SHALE with some grey shale, moist. Red SHALE with trace grey shale grading to more weathered, moist to wet. Red and greenish gray SHALE, red and yellow mottling, slickensides, moist to wet. 000236 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project# 18983633.00014 Date Started Date Completed Well Diameter Drilling Method Sampling Method LLMW-13B July 15.2002? July 16, 2002 4" Air Coring Continuous (page 5 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 462147.898' 2237960.343' Vernon Lucinda Tilton <OD) U. . oQ<U. 100- Surf. Elev. O X D- oO! DESCRIPTION Well: LLMW-13B Elev.: 105- 110- 115- Greenish grey SHALE, yellow and red mottling, slickensides, moist. Greenish grey silty SHALE, slickensides, grades to clayey with red mottling, moist. - Grout Gray SHALE, red mottling, slickensides, moist. Medium to coarse greenish gray SANDSTONE, micaceous, dry to moist. -PVC 120125- Greenish grey silty SHALE, moist to wet, slickensides. Red SHALE, with grey shale, slickensides, moist to wet. Fine to medium sandy gray green SILTSTONE. Fine to coarse green/gray silty SANDSTONE, micaceous, darker grey \la y prin g in thin.-beds dry In m n k t -Bentonite Seal -Sand Pack 0 0 2 3 7 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project# 18983633.00014 Date Started Date Completed Well Diameter Drilling Method Sampling Method LLMW-13B July 15, 2002? July 16.2002 4" Air Coring Continuous (page 6 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 462147.898' : 2237960.343' : Vernon : Lucinda Tilton aatt C oat. a 125- Surf. Elev. 0 1 0L DESCRIPTION col Fine silty SANDSTONE, grey/green, micaceous, dark grey layering in thin beds, dry to moist. Well: LLMW-13B Elev.: -PVC 130135- Fine greenish grey silty SANDSTONE, micaceous, dry to moist. Fine grey sandy SILTSTONE, dry to moist. Fine greenish grey silty SANDSTONE, micaceous, slickensides, dry to moist, with trace shaley fractured areas, grains coarsen with depth, dry to moist. -- Sand Pack Screen 140145- Fine greenish gray SHALE, fractured, slickensides, dry to moist. TD hole @ 140.5'. 150- 000238 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project# 18983633.00014 Date Started Date Completed Well Diameter Drilling Method Sampling Method LLMW-14B July 9. 2002 July 10, 2002 4" Air rotary/rotosonic Split spoon/continuous (page 1 of 3) Company Northing (W V St PI) Easting Coord. Survey By Logged By Bowser Momer 462468.458' 2236140.022' Vernon Lucinda Tilton Well: LLMW-14B Elev.: 672.040' OQ0). DESCRIPTION Silty CLAY with some organic debris, with some fine to medium gravel, ^moist, some mottling.________ j L- Yellowish brown weathered fine grained SANDSTONE chunks, micaceous, moist. Reddish brown silty CLAY, with some fine grained sandstone gravel, little mottling, micaceous, moist. Poor recovery, some weathered shale gravel, little organics, moist, getting dry by -1 0 '. Hit refusal at 12'. 10- -PVC Reddish brown silty SHALE, dry, competent all the way down. Drilled to 19' to set casing. -Grout 15- Soft, moderately weathered reddish brown SHALE. 29-33' is 20- predominantly reddish brown silty SHALE breccia, moderately weathered, green gray, red mottling, somewhat fractured, dry. 25- 000239 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Local Landfill Project # 18983633.00014 Date Started Date Completed Well Diameter Drilling Method Sampling Method LLMW-14B July 9, 2002 July 10, 2002 4" Air rotary/rotosonlc Split spoon/continuous (page 2 of 3) Company Northing (WV St PI) Easting Coord. Survey By Logged By Bowser Momer 462468.458' 2236140.022' Vernon Lucinda Tilton Surf. Elev. O<CuL 25- 0 1CL o DESCRIPTION L>tUr Well: LLMW-14B Elev.: 672.040' 3035404550- Rock grades to a greenish gray clayey SILTSTONE, slickensides present and fractures, little red and yellow mottling, becomes more competent, dry Oho-'' Grout PVC Greenish gray clayey SILTSTONE, fairly competent, little slickensides, dry, fractures intermittently. Greenish gray silty fine grained SANDSTONE, trace mica, sandstones grains coarsen with depth, fine to medium. Bentonite Seal Sand Screen Greenish gray clayey SILTSTONE, some thin reddish layers, slickensides, moderately fractured. r-'7 000240 1)0 0 2 4 1 APPENDIX C 000242 APPENDIX C BORING LOGS AND WELL CONSTRUCTION DIAGRAMS - LETART LANDFILL 00243 URS DuPont Corporate Remediation Group Washington Works Consent Order W ell Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method August 12. 2002 August 13,2002 4" Air coring Continuous LMW-12 (page 1 of 5) Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 696125.515' 1735234.766' Vernon Lucinda Tilton 0<u) u. Surf Elev. cuQ . O 740.12 O X Q. o DESCRIPTION - 740 Casing set at 14'. Reddish brown clayey SHALE at - 1'. Well: LMW-12 Elev.: 742.62' 5 - 735 1 0 - - 730 15- - 725 20- - 720 25- -PVC Greenish gray and greenish brown SHALE, fractured, orange mottling and orange/rust colored thin beds, dry to wet. Greenish gray fine grained SANDSTONE, with dark grey thin layering, micaceous, trace shale, dry. -Grout Greenish gray and orange brown fine SANDSTONE, micaceous, orange mottling, dark gray thin layering, little shale, dry. Orange brown, fine to coarse SANDSTONE, coarsening downward, orange mottling, micaceous, moist to wet. Orange brown medium to coarse SANDSTONE, micaceous, orange mottling, moist. 000244 ,-ks\Drill logs for Summer 2002LMW-12.bor 01-21-2003 I; URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method August 12, 2002 August 13,2002 4" Air coring Continuous LMW-12 (page 2 of 5) Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 696125.515' 1735234.766' Vernon Lucinda Tilton (oU> Surf. Elev. cuQ . 740.12 Q 2 5 - 715 30- 710 O Well: LMW-12 X O. O DESCRIPTION caoo<>c>u Elev.: 742.62' Orangish brovyn and greenish gray medium to coarse SANDSTONE, micaceous, some quartz crystals, moist to wet. Orange brown medium to coarse SANDSTONE, micaceous, orange mottling, large mica, some quartz crystals, moist to wet. 01-21-2003 r~~ ,rks\Drill logs for Summer 2002\LMW-12.bor 35- 705 40 -- - 700 45- 695 50 -- Orange brown and greenish gray coarse grained SANDSTONE, micaceous, very mottled orange/rust colored, moist to wet. Greenish gray medium to coarse SANDSTONE, micaceous, with trace green shale, dark grey thin layers, dry to moist, little orange mottling. Greenish gray medium grained SANDSTONE, and greenish gray SHALE mixed together, fractured, micaceous, dry to moist. Dark reddish brown SHALE and some gray SHALE, slickensides, very fractured, wet. Greenish gray SHALE, very little red SHALE, little slickensides, very fractured, wet. Greenish gray fine sandy SILTSTONE, micaceous, dry to moist with thin dark gray layering, some greenish gray shale from 48.5 to 56.6'. -PVC -G rout 000245 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project # 18983632.00015 Oate Started Date Completed Well Diameter Drilling Method Sampling Method August 12, 2002 August 13,2002 4" Air coring Continuous LMW-12 (page 3 of 5) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros . 696125.515' : 1735234 766' : Vernon : Lucinda Tilton u0a>.) Surf. Elev. ad>CL 740.12 5 0 -, 690 O X CL o DESCRIPTION Well: LMW-12 &c>u Elev.: 742.62' 8<u ce 5 5 - - 685 60- 680 65- - 675 70- 670 Greenish gray SHALE, dry, very competent. Greenish gray fiend sandy SILTSTONE, micaceous, with thin dark gray layering, dry. Greenish gray and reddish brown SHALE, dry. Brown shale and slicks from 162-164'. Greenish gray sandy SHALE, slickensides, dry. CD PVC Grout 75- 000246 jrks\DrilJ logs for Summer 2002M.MW-12.bor 01-21-2003 t URS DuPont Corporate Remediation Group Washington Works Consent Order W ell Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method August 12, 2002 August 13,2002 4" Air coring Continuous LMW-12 (page 4 of 5) Company Northing (W V St PI) Easting Coord. Survey By Logged By Duncan Bros 696125.515' 1735234.766' Vernon Lucinda Tilton Li. C Surf Elev. <QD. 740.12 o O X CL o DESCRIPTION 75- - 665 Sandy SHALE (cont.). 80- - 660 Well: LMW-12 0>) Elev.: 742.62' a. Grout PVC s' to to Bentonite rks\Drill logs for Summer 2002\LMW-12.bor 8 5 -, 655 90- 650 9 5 - - 645 100- Greenish gray SHALE, slickensides, sandy, competent, dry. Greenish gray fine grained sandy SILTSTONE, dry. o' oo Greenish gray fine to medium sandy SILTSTONE, micaceous, dark gray, thin layers, dry. Greenish gray, fine to medium SANDSTONE, micaceous, dark thin gray layers, dry, competent. Screen Sand Greenish gray medium to coarse SANDSTONE, micaceous, dry, competent.______________________________________________________ Greenish gray fine to medium SANDSTONE, micaceous, thin dark gray layers, dry, competent.____________________________________________ Grenish gray medium to coarse SANDSTONE with trace green/gray SHALE, micaceous, trace reddish staining, dry to moist, competent. ,, ^ 000247 01-21-2003 I, URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project # 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method August 12, 2002 August 13,2002 4" Air coring Continuous LMW-12 (page 5 of 5) Company Northing (W V St PI) Easting Coord. Survey By Logged By Duncan Bros 696125.515' 1735234 766' Vernon Lucinda Tilton <<uu Surf. Elev. a. aCD 740.12 a x CL o DESCRIPTION 100- 640 Greenish gray SANDSTONE (cont.). Well: LMW-12 Elev.: 742.62' - Screen -Sand 105- - 635 Greenish gray, clayey SHALE, slickensides, wet. Greenish gray SHALE, less clayey, very fractured, slickensides, wet. Reddish brown, bright red and greenish gray SHALE, very fractured, yellow brown and purple mottling abundant, slickensides, wet. 110- - 630 Greenish gray SHALE, slickensides, moist. Greenish gray fine grained sandy SILTSTONE, micaceous, dry. -Slump? 115- - 625 120- - 620 TD hole at 119' bgs. ,rks\Drill logs for Summer 2002MMW-12.bor 01-21-2003 I; 125- 000248 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-13B/A : August 12, 2002 (B) : August 15, 2002(A) : 4" : Air Coring : Continuous (page 1 of 8) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 695192.499' : 1735216.906' : Vernon : Lucinda Tilton Surf. Elev, OC<1>L O Well: LMW-13B X Q. CS) DESCRIPTION a>> Elev.: a80s) Casing installed to 14'. *** Shallower bedrock well (LMW-13A) screened from 130-150' bgs, sand from 125-150', bentonite from 120-125', and grouted to surface from 120'. Coordinates 695193.486 N, 1735205.550 E, TOC at 766.250' 10- -PVC :-- Grout Greenish gray fine to medium SANDSTONE, competent with some thin 15- dark gray layering, trace orangish rust colored layering, micaceous, dry. Light brown to orange medium to fine SANDSTONE, with little dark orange/ gray layering, micaceous, some dark orange mottling, moist to wet. 20- Greenish gray fine to medium SANDSTONE, with some thin dark gray layering, micaceous, Little dark orange mottling, dry. Greenish gray SHALE, very fractured, little clayey, slickensides, trace 25- red and green mottling, moist to wet. 000249 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-13B/A August 12. 2002 (B) August 15. 2002 (A) 4" Air Coring Continuous (page 2 of 8) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros :695192.499' : 1735216.906' : Vernon : Lucinda Tilton a<u) Surf Elev. O<D 25 Well: LMW-13B 0 1 Elev.: CL DESCRIPTION 2o cc Greenish tan, gray and red clayey SHALE, very fractured, abundant yellow, red and greenish mottling, slickensides, wet._________________ Reddish brown clayey SHALE, very fractured, abundant yellow mottling with trace greenish gray shale, slickensides, wet. 0> 30- I I I I i i i I t I I Greenish gray fine sandy SILTSTONE, with some clay, moist. I I I I I I I I I I I I Greenish gray and some red SHALE, slickensides, dry to moist. 35- Greenish gray sandy SILTSTONE, trace micaceous, trace slickensides, dry to moist. fO-O 40Greenish gray fine to medium silty SANDSTONE, micaceous, trace orange/rust mottling with trace fractures, little quartz crystals, dry. PVC Grout 45- Ii'/s*t*rI 50- Greenish gray fine sandy SILTSTONE, trace red siltstone and mica, dry. SILTSTONE, with some red/brown siltstone and little intermixed sections of gray/red/brown shale with slickensides. Co>O 000250 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-13B/A August 12, 2002 (B) August 15, 2002 (A) 4" Air Coring Continuous (page 3 of 8) Company Northing (W V St PI) Easting Coord Survey By Logged By Duncan Bros 695192.499' 1735216.906' Vernon Lucinda Tilton 0<D) LiC Surf. Elev. aO0 . 50- 55- O X CL DESCRIPTION o Greenish gray SHALE, trace mica and little slickensides and trace \fractures, dry.______________________________________________ Greenish gray fine sandy SILTSTONE, trace mica, dry. Greenish gray SHALE, trace fractures, dry. Reddish brown and gray SHALE, very fractured, abundant yellow/brown and purple mottling, slickensides, moist to wet. Greenish gray SHALE, trace sandy, trace mica, dry. Greenish gray fine sandy SILTSTONE, little micaceous, trace fractures containing orange/rust colored thin layers, dry. Well: LMW-13B Elev.: 60- Greenish gray fine to medium silty SANDSTONE, micaceous, dry, with some thin darker gray layering. -PVC Greenish gray SHALE, with trace mica, trace dark grey layering, dry. -Grout 65SHALE, with some reddish brown shale, trace fracturing. SHALE, with abundant fractures, abundant yellow and reddish brown mottling. Little clayey, dry to moist., 70- Greenish gray SHALE with ittle reddish brown shale, slicks, dry. Greenish gray fine silty SANDSTONE, micaceous, little tannish brown mottling, dry. 75- 0025JL URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project # 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-13B/A August 12. 2002 (B) August 15, 2002 (A) 4" Air Coring Continuous (page 4 of 8) Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 695192.499' 1735216.906' Vernon Lucinda Tilton Surf. Elev. Q<QD. 75- 80- O X oC<ccL DESCRIPTION Greenish gray sandy SHALE, very fractured, slickensides, dry to moist. Greenish gray fine silty SANDSTONE, micaceous, dry. Very fine grained in bottom 3'. Well: LMW-13B Elev.: Greenish gray sandy SHALE, slickensides, dry to moist. 85- Reddish brown and greenish gray SHALE, sandy, slickensides, dry. -PVC - Grout Greenish gray and reddish brown fine sandy SILTSTONE, micaceous, some slickensides, dry. 90- 95100- Greenish gray and reddish brown clayey SHALE, slickensides, fractured, dry to moist. Decreasing clay with depth, trace yellow mottling with depth. 000252 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 ~ Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-13B/A August 12. 2002 (B) August 15. 2002 (A) 4" Air Coring Continuous (page 5 of 8) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 695192.499' : 1735216.906' : Vernon : Lucinda Tilton <<uu LCi. Q0 . O 100- Surf. Elev. O X CL < DESCRIPTION o: o SHALE with some yellow mottling, moist to wet. Well: LMW-13B >CD Elev.: c8<cu 105- - Greenish gray sandy SHALE, slickensides, dry. Greenish gray sandy SILTSTONE, with some reddish siltstone, micaceous, very fine grained, dry. 110115- SILTSTONE, grainsize goes from very fine to medium and back to very fine with depth. I Greenish gray and reddish brown SHALE, little sandy, slickensides, - moist, slightly fractured. PVC Grout 120125- Greenish gray SHALE, sandy, slickensides, dry. Reddish brown clayey SHALE, with little green gray shale, very fractured, abundant slickensides, abundant yellow and brown and purple mottling, moist to wet. 000ZS3 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project # 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-13B/A (page 6 of 8) August 12. 2002 (B) August 15. 2002 (A) 4" Air Coring Continuous Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 695192.499' : 1735216.906' : Vernon : Lucinda Tilton Surf. Elev. OQ<U. 125- 0 1 oC<aL. DESCRIPTION Well: LMW-13B Elev.: -PVC 130135140- SHALE, very mottled with yellow and purple. Reddish brown, clayey SHALE, very fractured with some yellow and purple mottling, slickensides, moist to wet, (ZONE D/E). Greenish gray fine grained SILTSTONE, sandy, micaceous, fractured, moist to wet. Greenish gray medium grained SANDSTONE, with some thin dark gray layering and some layers of greenish gray competent SHALE throughout, micaceous, dry. (Zone D/E). Bottom 3' have little orangish mottling. - Grout - Screen (A) 145- 150- 000254 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project # 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-13B/A August 12. 2002 (B) August 15. 2002 (A) 4" Air Coring Continuous (page 7 of 8) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 695192.499' : 1735216.906' : Vernon : Lucinda Tilton 0cl)) Surf Elev. OQ<D. 150 O Well: LMW-13B Elev.: X CL DESCRIPTION o a. Greenish gray SHALE, with little reddish shale, slickensides, fracturing, trace mica, dry to moist. 155- Reddish brown SHALE with little greenish gray shale. Some yellow/brown/purple mottling, fractured, slightly clayey, slickensides, moist. Grout 160165170175- Greenish gray sandy fine SILTSTONE, with some reddish brown siltstone, grades downhole to SHALE, slickensides, dry to moist. PVC Bentonite Greenish gray fine silty SANDSTONE, micaceous, little thin layers of gray shale intermittently, dry, competent (ZONE F). I Greenish gray SHALE, competent, dry.______________________________ I Greenish gray fine to medium SANDSTONE, very micaceous, thin dark - gray layering, dry (ZONE F). Sand Screen (B) 000255 4)00256 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project # 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-14B/A : August 18. 2002 : August 22, 2002 : 4" Air Coring : Continuous (page 1 of 9) Company Northing (WV St PI) Easting Coord Survey By Logged By : Duncan Bros :695249.939' : 1735999.611' : Vernon : Lucinda Tilton t<uu Surf. Elev. OQ<D. 764.6 0- 764 O Xa<aa.: DESCRIPTION >cc Well: LMW-14B LU Elev.: 767.10' cc Bore to 14' by Bowser. Coring starts at 14'. " Shallow well LMW-14A set from 136-156 BGS. Sand from 156 to 134, Bentonite from 129-134', and Grout to surface. Coordinates 695263.466 N, 1736000.799 E, TOC @ approx. 767'. 5- 759 -Casing 10- 754 15- 749 20- - 744 25- -PVC Brown medium grained SANDSTONE, micaceous, wet, some white and orange coloring around small fractures_____________________________ brown & light greenish grey medium grain SANDSTONE, micaceous, wet, some orange mottling and fractures Brown, medium grained SANDSTONE, micaceous, wet, some orange mottling Brown and light greenish grey medium to course grain SANDSTONE, micaceous, orange mottling (heavy around fractureas), wet 5O^J CD : -- Grout : Brown and light greenish grey medium to course grain SANDSTONE, ^micaceous, orange mottling ( heavy around fractures), wet_________ 000257 URS DuPont Corporate Remediation Group Washington Works Consent Order W ell Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-14B/A August 18. 2002 August 22, 2002 4" A ir Coring Continuous (page 2 of 9) Company Northing (W V St PI) Easting Coord. Survey By Logged By : Duncan Bros : 695249.939' : 1735999.611' : Vernon : Lucinda Tilton u<<uu. Surf. Elev. a)Q. O 764.6 25 739 30- 734 O X0- o DESCRIPTION >oc Well: LMW-14B >LU Elev.: 767.10' ooUaJ: ! Greenish grey SHALE, very fractured, trace brown shale, moist to wet, - slick & slides___________________________________________________ Greenish grey and reddish brown SHALE, slightly clayey and fractured, ; some brown and red and yellowish and dark grey mottling, moist to -\wet, slick & slides_______________________________________________ Greenish grey, reddish brown, tannish clayey SHALE, very fractured, ; lots of slick & slides, purple, red, brown, and yellow mottling, soft, moist to wet eg 35729 40- 724 45 719 50- Reddish brown clayey SHALE, very fractured, little grey shale, yellow, purple and brown mottling, wet, slick & slides ^Greenish grey SHALE, some reddish brown shale, slick & slides, moist Reddish brown and greenish grey SHALE, trace clay, slick & slides, moist to PVC Grout Reddish brown SHALE, w/ some greenish gray shale, slickensides, trace yellow mottling, dry to moist - Greenish gray SHALE with some reddish brown SHALE, slickensides, I \dry to moist.__________________________________________________ L 'Reddish bron and greenish gray SHALE, slickensides, dry to moist. I Greenish gray fine SANDSTONE, silty, micaceous, grades downward - to siltstone, oange/rust colored staining on fracture, dry. Reddish brown and greenish gray SHALE, with trace yellow mottling, slickensides, dry to moist. 05 000258 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-14B/A August 18, 2002 August 22, 2002 4" Air Coring Continuous (page 3 of 9) Company Northing (WV St PI) Easting Coord Survey By Logged By : Duncan Bros : 695249.939' : 1735999.611' : Vernon : Lucinda Tilton 0) CD Surf. Elev. CL o0) 764.6 50 - 714 55- 709 O X C<Ce>Ld DESCRIPTION >Cd- Well: LMW-14B >LU Elev.: 767.10' oo LCUd Reddish brown SHALE, with little greenish gray shale, slickensides, some fracturing, trace sandy, dry to wet (wet @ fractures). Greenish gray SHALE, with some reddish brown shale, alternating slickensides, fairly competent, sandy, dry to moist. OTT) irn-. 60- 704 65-699 Reddish brown SHALE, with some dark gray shale, very fractured, gets clayey with depth, abundant yellow, purple brown mottling, moist to wet. PVC Grout Greenish gray SI LISTONE, little sandy, competent, dry. oo 70- 694 pm 75- Greenish gray SHALE, with some reddish brown shale, very fractured, abundant yellow and purple mottling, wet, slickensides. Greenish gray, silty fine grained SANDSTONE, micaceous, competent, dry, with some greenish gray SHALE. rc*o- 000259 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-14B/A August 18, 2002 August 22. 2002 4" Air Coring Continuous (page 4 of 9) Company Northing (W V St PI) Easting Coord. Survey By Logged By Duncan Bros 695249.939' 1735999.611' Vernon Lucinda Tilton Surf. Elev. QQCU. 764.6 75- 689 O X CL o DESCRIPTION Well: LMW-14B Elev.: 767.10' 80- 684 85679 90- 674 95669 pill ww 100- Greenish gray silty fine grained SANDSTONE, micaceous, competent, with some greenish gray shale and trace reddish brown shale, dry. Dark greenish gray and brown SHALE, slickensides, fairly competent, dry to moist. Dark reddish brown and dark gray SHALE, trace yellow mottling, slickensides, moist to wet. Bright reddish brown SHALE, fractured, trace yellow mottling, slickensides, moist to wet. Brownish gray and reddish brown SHALE, slickensides, little fracturing, moist to wet. -PVC - Grout 000260 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project # 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-14B/A : August 18, 2002 : August 22, 2002 : 4" : Air Coring : Continuous (page 5 of 9) Company Northing (WV St PI) Easting Coord Survey By Logged By : Duncan Bros : 695249.939' : 1735999.611' : Vernon : Lucinda Tilton <Vu LL Surf. Elev. o<DCL 764.6 100- - 664 105659 O X O- DESCRIPTION o Reddish brown SHALE, w/ trace greenish gray shale, slickensides, little fracturing, slightly clayey, moist to wet. Greenish grey fine grained sandy SILTSTONE, trace micaceous, dry. Reddish brown and some greenish gray SHALE, some fracturing, slickensides, little yellow brown and purplish gray mottling, moist to wet. Well: LMW-14B Elev.: 767.10' 110- - 654 115649 120- 644 125- Reddish brown SHALE, with trace greenish gray shale, very fractured, abundant slickensides, some yellow mottling, moist to wet. -PVC -Grout Greenish gray, fine grained sandy SILTSTONE, a little micaceous, dry. Reddish brown and greenish gray SHALE, fractured, slickensides, wet. Greenish gray fine sandy SILTSTONE, micaceous, dry. Reddish brown sandy SHALE, trace fractured, slickensides, dry to moist. Reddish brown and greenish gray sandy SHALE, trace fractured, slickensides, dry to moist. Greenish gray fine sandy SILTSTONE, micaceous, dry. 000261 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-14B/A August 18, 2002 August 22, 2002 4" Air Coring Continuous (page 6 of 9) Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 695249.939' 1735999.611' Vernon Lucinda Tilton Surf. Elev. 764.6 O I CL < o: o DESCRIPTION >a-. Well: LMW-14B >LU Elev.: 767.10' ooma. r0-5 130- 634 Greenish gray medium to coarse SANDSTONE, micaceous, some quartz grains, some greenish gray SHALE lenses throughout, bronish gray thin layering, dry. oin> PVC 135- 629 140- 624 SANDSTONE, with less shale, only trace amount, also with trace brown mottling. Grout Screen (A) 145- 619 150- Brown medium SANDSTONE, micaceous, with some small orange crystals, dry to moist. Greenish gray medium to coarse SANDSTONE, micaceous, some quartz grains, trace greenish gray shale, w/ brownish gray thin layering, dry to moist. CO 05 m o zsz URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project # 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-14B/A August 18. 2002 August 22, 2002 4' Air Coring Continuous (page 7 of 9) Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 695249.939' 1735999.611' Vernon Lucinda Tilton Surf. Elev. <uQ. 764.6 D 150614 0 1 CL o DESCRIPTION Well: LMW-14B Elev.: 767.10' - Screen (A) 155609 160604 Greenish gray sandy SHALE, slickensides, dry. Greenish gray and reddish brown SHALE, sandy, slickensides, dry. Greenish gray sandy SHALE, slickensides, dry. -Grout 165- 599 170- 594 175- Reddish brown SHALE with little greenish gray shale, very fractured, slickensides, trace yellow/purplish mottling, moist to wet. -PVC Greenish gray fine grained sandy SILTSTONE and some sandy SHALE, trace micaceous, with trace reddish brown shale also, dry. Bentonite Seal 000263 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-14B/A August 18, 2002 August 22, 2002 4" Air Coring Continuous (page 8 of 9) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 695249.939' : 1735999.611' : Vernon : Lucinda Tilton <o>u Surf. Elev. Oa>Q . 764.6 175- 589 O X 0- DESCRIPTION se> Greenish gray fine grained silty SANDSTONE, with some greenish gray shale throughout, micaceous, competent, thin dark gray layering, dry. Well: LMW-14B Elev.: 767.10' -PVC 180- 584 185579 190574 195569 200- Greenish gray fine to coarse SANDSTONE, silty with some greenish gray SHALE throughout, micaceous, competent, thin dark gray layering, 3[dry._________________________________________ Greenish gray and reddish brown SHALE, trace fractures, \slickensides, dry to moist._____________________________ Green gray fine to medium silty SANDSTONE, with some greenish gray shale throughout, micaceous, thin dark gray layering, dry. SAA but medium to coarse grained SANDSTONE. By 194' have some gold brown crystals in small circles througout and SANDSTONE grains are fine to coarse. -- Sand Screen (B) Greenish gray and reddish brown SHALE, some fractures, slickensides, trace dark red brown mottling, dry to moist. 00tt24 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Letart Landfill Project# 18983632.00015 Date Started Date Completed Well Diameter Drilling Method Sampling Method LMW-14B/A August 18. 2002 August 22, 2002 4" Air Coring Continuous (page 9 of 9) Company Northing (W V St PI) Easting Coord Survey By Logged By : Duncan Bros : 695249.939' : 1735999.611' : Vernon : Lucinda Tilton Surf. Elev. 764.6 200- - 564 O X a. < DESCRIPTION a: CD - Reddish brown SHALE, with some greenish gray and tan shale, - abundant fractures, abundant slicks, abundant yellow purple, red . brown, orange and greenish brown mottling, moist to wet. 205559 TD hole at 203.5'. Well: LMW-14B Elev.: 767.10' Slump 210- 554 215549 220- 544 225- 000265 APPENDIX D 1)00266 APPENDIX D BORING LOGS AND WELL CONSTRUCTION DIAGRAMS - DRY RUN LANDFILL 000267 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Dale Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-16B August 1.2002 August 1.2002 4" Air Coring Continuous (page 1 of 7) Company Rep. Northing (WV St PI) Easting Coord Survey By Logged By : Duncan Bros : 256225.576 : 1380203.004 . Vernon : Lucinda Tilton Surf. Elev. Oocu. O X C<occL DESCRIPTION Casing in hole to 32'. Well: DRMW-16B Elev.: 789.965' 1015- 20- SHALE encountered at -11'. No other geologic info to bottom of casing. -PVC ?-- Grout 25- 000268 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-16B August 1, 2002 August 1,2002 4" Air Coring Continuous (page 2 of 7) Company Rep. Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256225.576 : 1380203.004 : Vernon : Lucinda Tilton Surf. Elev. Oaa>. 25- O X C<oocL. DESCRIPTION Well: DRMW-16B Elev.: 789.965' - Grout 3 0 - PVC Greenish gray sandy fine grained SILTSTONE, micaceous, dry. Bentonite Greenish gray, fine to coarse SANDSTONE with dark gray thin layering, micaceous, dry. 35- 40- -Sand -Screen 45- 50- 000269 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-16B August 1, 2002 August 1,2002 4" Air Coring Continuous (page 3 of 7) Company Rep. Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256225.576 : 1380203.004 : Vernon : Lucinda Tilton Ucaa_)t Surf. Elev. Oaa>. 50- O x Q<VoCl DESCRIPTION SANDSTONE, cont. Well: DRMW-16B Elev.: 789.965' - Screen 55- -Sand Greenish gray SHALE, clayey, trace mica, moist Reddish brown SHALE, clayey, little greenish gray SHALE, moist. 60SAA- SHALE, fractured, slickensides, moist to wet. Greenish gray SHALE, with trace reddish brown shale, trace fractures, \dry to moist._________________________________________ 65- Greenish gray silty fine grained SANDSTONE, micaceous, dry. Greenish gray fine-grained sandy SILTSTONE, mixed with a greenish gray SHALE, trace slickensides, dry. -Bentonite 70- Reddish brown clayey SHALE, very fractured, little gray shale, abundant yellow and purplish red mottling, slickensides, wet. 75- 0002/0 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-16B August 1, 2002 August 1,2002 4" Air Coring Continuous (page 4 of 7) Company Rep. Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 256225.576 1380203.004 Vernon Lucinda Tilton n<>u Surf. Elev. C<DL Q 75- O X CL o DESCRIPTION Well: DRMW-16B Elev.: 789.965' 80- 859095100- Greenish gray SHALE, with some reddish brown shale, trace micaceous, dry, trace slickensides. greenish gray sandy fine grained SILTSTONE, micaceous, some thin darker grey layering, dry. -Bentonite Greenish gray SHALE, with some reddish brown shale, micaceous, dry. Slickensides from 99-102'. 00271 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-16B August 1, 2002 August 1,2002 4" Air Coring Continuous (page 5 of 7) Company Rep. Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 256225.576 1380203.004 Vernon Lucinda Tilton oo cu_ CL OCD 100- Surf. Elev. O <X0tor. DESCRIPTION Well: DRMW-16B - Elev.: 789.965' 105- Reddish brown SHALE, with some greenish gray shale, fractured, slickensides, yellow and purplish mottling, dry to moist. cn 110115 -- SAA- SHALE, moist to wet. Clayey in bottom 4'. Bentonite CO L-- 120125- Fine sandy SILTSTONE, greenish gray, trace mica, dry. O -000272 URS DuPont Corporate Remediation Group Washington Works Consent Order W ell Installation Dry Run Landfill Project #18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-16B (page 6 of 7) : August 1, 2002 : August 1,2002 : 4" : Air Coring : Continuous Company Rep. Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 256225.576 1380203.004 Vernon Lucinda Tilton g OQa). 125- Surf. Elev. 0 1 exQ. < CD DESCRIPTION Well: DRMW-16B Elev.: 789.965' 130- Fine silty SANDSTONE, greenish gray, micaceous. Fine sandy SILTSTONE, micaceous, greenish gray, some shale. Reddish brown SHALE with some greenish gray, slickensides, fractured, moist to dry. 135140- Greenish gray fine grained sandy SILTSTONE, trace micaceous, dry. Reddish brown and greenish gray SHALE, slickensides, trace fractures, trace mica, dry to moist. -Bentonite 145- 150- Grenish gray fine silty SANDSTONE, dry, micaceous. Greenish gray sandy SILTSTONE and shale, trace slickensides, dry, 000273 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-16B : August 1,2002 : August 1,2002 : 4" : Air Coring : Continuous (page 7 of 7) Company Rep. Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256225.576 : 1380203.004 : Vernon : Lucinda Tilton la<cl.u) Surf. Elev. a 150- g x CL 2o num ilii DESCRIPTION Reddish brown SHALE, with a little gray shale, fractured, slickensides, dry to moist. Well: DRMW-16B > Elev.: 789.965' C8aC> 155160- SAA - SHALE, with some yellow and purple mottling, fractures increase with depth, moisture increases with depth, moist to wet. a- eg o Bentonite 165- TD hole at 165.5'. 170- 175- 000274 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-17B (page 1 of 1) August 1,2002 August 1,2002 4" Air Coring Continuous Company Rep. Northing (W V St PI) Easting Coord. Survey By Logged By Duncan Bros 255809.466 1380365.817 Vernon Lucinda Tilton Surf. Elev. Q(1). Q 0- 51015- 20- 253035404550556065707580859095100105110115120125130135140145150- O X toQ<r- DESCRIPTION ****DATA FOR BORING IS FROM DRILLER'S LOG* Brown CLAY Brown and red SHALE Red and gray SHALE. Green/gray SANDSTONE. Red and green/grey SHALE. Green/gray SANDSTONE. Red and green/gray SHALE. Green/gray SANDSTONE. Red and green/gray SHALE. TD hole at 129'. Well: DRMW-17B o>> Elev.: 850.270' CaooC> PVC -- Grout II Bentonite -- Sand SCREEN 000275 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method July 29, 2002 July 30, 2002 4" Air Coring Continuous DRMW-18B (page 1 of 9) Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 255363.986 1381085.449 Vernon L. Tilton/G. Donahue Q. oCD 0- Surf. Elev. O X CL 2o Reddish CLAY. DESCRIPTION Well: DRMW-18B a>> Elev.: 924.150' o8ac> 5Weathered bedrock... SHALE? becoming more competent with depth. 10- Grout -PVC 15- Greenish gray fine to medium SANDSTONE with darker grey thin layers, micaceous at 23.5'. Looks like a fracture with abundant orange/red mottling, dry to moist. 20- 25- 000276 URS DuPont Corporate Remediation Group Washington Works Consent Order W ell Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-18B July 29, 2002 July 30, 2002 4" Air Coring Continuous (page 2 of 9) Company Northing (W V St PI) Easting Coord Survey By Logged By Duncan Bros 255363.986 1381085.449 Vernon L. Tilton/G. Donahue <<uu Surf. Elev. aQa>. 25- 0 1 0- DESCRIPTION Well: DRMW-18B (>U Elev.: 924.150' oooVr 303540- Greenish gray clayey SHALE, fractured, little red mottling. Less clayey from 29' to 29.5'. Reddish brown clayey SHALE, some greenish gray shale, moist. Greenish gray silty fine SANDSTONE, micaceous, moist to wet. moo ^G reenish gray SHALE, red mottling, dry to moist_____________________ Greenish gray fine sandy SILTSTONE, little mica, orange mottling about . 39.5', dry to moist._______________________________________________ Greenish gray fine sandy SILTSTONE, micaceous, orange and red mottling, little shale throughout, dry to moist. Grout PVC 45- - Reddish brown SHALE, with some greenish gray shale, fractured, slickensides, wet. 50- 00J277 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method July 29, 2002 July 30, 2002 4" Air Coring Continuous DRMW-18B (page 3 of 9) Company Northing (W V St PI) Easting Coord. Survey By Logged By : Duncan Bros . 255363.986 : 1381085.449 : Vernon : L. Tilton/G Donahue <<Du Surf. Elev. 0) O 50- O X Q<Xo DESCRIPTION Well: DRMW-18B Elev.: 924.150' 55Greenish gray sandy SHALE, some red mottling, dry to moist. 60- Reddish brown SHALE, little greenish gray shale, fractured, slickensides, moist. 63-66.5' is the same with only trace greenish gray shale and yellow and purplish mottling, zone is wet. -Grout -PVC 65- Greenish gray SHALE, with some reddish brown shale, trace micaceous, dry to moist. 70- Greenish gray sandy SILTSTONE, micaceous, fine to medium grained, dry. Greenish gray medium to coarse grained SANDSTONE, micaceous, trace red mottling, moist. 75- Greenish gray fine grained silty SANDSTONE, trace mica, orangish mottling, mnist_______________________________________________ 000278 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method : July 29. 2002 : July 30. 2002 : 4" : Air Coring : Continuous DRMW-18B (page 4 of 9) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 255363.986 . 1381085.449 : Vemon : L. Tilton/G. Donahue a<u) Surf. Elev OQ<u. 75- O X Q. DESCRIPTION $o Greenish gray SHALE, with reddish brown shale, yellow and brownish mottling, trace slickensides, grades with depth to more fractured and clayey, moist to wet. Well: DRMW-18B Elev.: 924.150' 80- Reddish brown, clayey, SHALE slickensides, yellow and purplish mottling, wet. SAA with little greenish gray shale. 85Grout PVC 90- 95- Greenish gray SHALE, trace micaceous, trace sandy, dry. Squeak said 2' of gray shale left in hole. 100- O00J273 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method July 29, 2002 July 30. 2002 4" Air Coring Continuous DRMW-18B (page 5 of 9) Company Northing (W V St PI) Easting Coord. Survey By Logged By Duncan Bros 255363.986 1381085.449 Vernon L. Tilton/G. Donahue <<1u> U- Surf. Elev. <u O 100- O X 0<oVC- DESCRIPTION Greenish gray SHALE, some reddish brown shale, trace micaceous, dry, trace fracturing. Well: DRMW-18B Elev.: 924.150' 105- 110115- SAA with only trace red shale and more micaceous. 108-112' above lacked fracturing. Some red mottling from 117.5-120.5'. Grout PVC 120- -- 125- Greenish gray silty fine to medium SANDSTONE, micaceous, dry. Light greenish gray clayey SHALE, red mottling, trace mica, moist with \slickensides. Reddish brown SHALE, slicks, fractured, trace gray shale, wet. 000280 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method July 29, 2002 July 30, 2002 4" Air Coring Continuous DRMW-18B (page 6 of 9) Company Northing (W V St PI) Easting Coord. Survey By Logged By Duncan Bros 255363.986 1381085.449 Vernon L. Tilton/G. Donahue Surf. Elev. Q. CD O 125- O X CL DESCRIPTION o SAA with yellow and purple mottling, abundant fractures. Well: DRMW-18B <>U Elev.: 924.150' c<8cD 130- 135140145150- Greenish gray silty fine to medium SANDSTONE, micaceous, dry Greenish gray medium to coarse SANDSTONE, micaceous, dry, with darker gray thin layers. -Grout -PVC Greeenish gray SHALE, trace mica, dry. SAA w/ slickensides, dry to moist. Greenish gray and reddish brown SHALE, fractured, slickensides, moist to wet, trace yellow and dark red mottling. Reddish brown, clayey SHALE, fractured, slickensides, abundant yp.llnw.and.purplp..mottling, wet--------------------------------------------------- 000251 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method July 29, 2002 July 30, 2002 4" Air Coring Continuous DRMW-18B (page 7 of 9) Company Northing <WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 255363.986 : 1381085.449 : Vernon : L. Tilton/G. Donahue 00) Q. CD Q 150- Surf. Elev. O X 0- (3 DESCRIPTION Well: DRMW-18B 0> Elev.: 924.150' c80c 155160165170175- Greenish gray sandy fine grained SILTSTONE, micaceous, little red mottlings, dry to moist. Grout PVC Greenish gray SHALE, slickensides, moist, trace mica, some fracturing. Greenish gray sandy fine grained SILTSTONE, micaceous, red mottling, with trace intermittent greenish gray SHALE, grainsize increases with depoth from fine to medium, dry. IoT>) Bentonite 000282 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method July 29. 2002 July 30. 2002 4" Air Coring Continuous DRMW-18B (page 8 of 9) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 255363.986 : 1381085 449 : Vernon : L. Tilton/G. Donahue LaaL) Surf. Elev. Qa>. D 175- 180- O X C<cLc DESCRIPTION Greenish gray fine to medium SANDSTONE, micaceous, dark gray thin layering, dry. Well: DRMW-18B Elev.: 924.150' I I Bentonite -PVC Greenish gray sandy SILTSTONE, fine grained, dry. Greenish gray medium grained SANDSTONE, very micaceous, trace red mottling, dark gray thin layering, dry. Some red mottling from 184-193'. 185190- - Screen -Sand 195200- Greenish gray SHALE, dry to moist. Greenish gray and brownish red SHALE, trace micaceous, fractured, trace slickensides, moist. -Sand or Bent. 0002S3 URS DuPont Corporate Remediation Group Washington Works Consent Order W ell Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method July 29, 2002 July 30, 2002 4" Air Coring Continuous DRMW-18B (page 9 of 9) Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 255363.986 1381085.449 Vernon L. Tilton/G. Donahue <u O 200- Surf. Elev. 0 1 CL DESCRIPTION aoi Reddish brown SHALE, with some gray shale and clay, slickensides with trace yellowish brown mottling. Shale is greenish gray with slicks and moist in bottom 1.5'. Well: DRMW-18B Elev.: 924.150' 205210- Greenish gray fine grained sandy SILTSTONE, micaceous, trace red mottling. Greenish gray medium to coarse SANDSTONE, very micaceous, dark gray thin layering, dry to moist. Greenish gray SHALE, fractured, slickensides, wet. After 2" becomes reddish brown SHALE, fractured, slicks, yellow and purple mottling, with trace gray shale, moist to wet. Highly fractured and clayey from 212.5-217'. Greenish gray shale with slickensides and trace mica, dry to moist to bottom of hole. -Sand or Bent. 215- 220225- TD hole at 220.5'. 000284 000255 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method : July 24, 2002 : July 25, 2002 : 4" : Air Coring : Continuous DRMW-19B (page 2 of 7) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256212.512' : 1381381.714' : Vernon : Lucinda Tilton 0<u) Ll. Surf. c0)l Elev. Q 25- O X CL DESCRIPTION >oL>ooL:-I Well: DRMW-19B Elev.: 880.270' LU X ^Orangish green SHALE, moist. Greenish gray sandy SHALE, micaceous, moist. Trace thin orangish red layering, reddish mottling in bottom 1.3'. 30Reddish brown, clayey SHALE, trace gray shale, moist to wet. 35PVC Grout Poor recovery above this interval, no recovery in this interval, NO 40- GEOLOGIC INFO. o 45- Reddish brown SHALE, trace greenish gray shale, slickensides, moist to wet. ior>>: 50- 0002S6 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-19B July 24, 2002 July 25, 2002 4" Air Coring Continuous (page 3 of 7) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256212.512' : 1381381.714' : Vernon : Lucinda Tilton (aU> Surf. aOa>- Elev. 50- 55- O X a DESCRIPTION 2o Greenish gray and reddish brown SHALE, slickensides, dry. Greenish gray, trace sandy SHALE, with trace red shale, slickensides, dry. Greenish gray, fine grained sandy SILTSTONE, micaceous, dry. Well: DRMW-19B Elev.: 880.270' Greenish gray SHALE, with some reddish shale, dry. Reddish brown SHALE, with some greenish gray and brown shale, slickensides, dry to moist. 60- -PVC Greenish gray clayey SHALE, slickensides, moist. Greenish gray fine to medium silty SANDSTONE, micaceous, dry. ?-- Grout 65- Reddish brown and greenish gray SHALE, slickensides, dry to moist. Interbedded layers of greenish gray fine to medium silty SANDSTONE and reddish brown and green-grey SHALE. Sandstone is micaceous. Layering is 0.25-6 inches wide, alternating. All dry. 70- Reddish brown, clayey SHALE, with trace mica, moist. 7 5 - Reddish brown and greenish gray SHALE, slickensides. moist. 000287 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method July 24, 2002 July 25, 2002 4" Air Coring Continuous DRMW-19B (page 4 of 7) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256212.512' : 1381381.714' : Vernon : Lucinda Tilton Surf. Elev. Q<D. O 75- o X Q<- DESCRIPTION X CD Reddish brown clayey SHALE, with trace gray shale, abundant sllckensides, trace yellow mottling, fractured, moist to wet. Well: DRMW-19B Elev.: 880.270' 80- SAA- with some yellow mottling, and some gray shale, very fractured. Very poor recovery. 85- -PVC ?-- Grout 90- 95100- Greenish gray clayey SHALE, slickensides, fractured, moist to wet. Greenish gray sandy SILTSTONE, fine grained, micaceous, dry, trace red mottling. 000288 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method : July 24, 2002 : July 25, 2002 : 4" : Air Coring : Continuous DRMW-19B (page 5 of 7) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256212.512' : 1381381.714' : Vernon : Lucinda Tilton Q. o<D 100- Surf. Elev. 105- o X oC<aL: DESCRIPTION Greenish gray SHALE, trace red mottling, dry. Reddish brown SHALE, with some greenish gray shale, slickensides, fractured, moist. Reddish brown SHALE, clayey, abundant slickensides, very fractured, abundant yellow and purple mottling, moist to wet. Well: DRMW-19B Elev.: 880.270' 110- 115120125- SAA with yellow/purple mottling, decreasing with depth. -PVC -Grout Greenish gray and red SHALE, slickensides, trace yellow mottling, moist. Greenish gray SHALE, slickensides, dry to moist. Fine to medium greenish gray SANDSTONE, silty, micaceous, dry. Medium to coarse, greenish gray SANDSTONE, micaceous, darker thin bands of grey, dry._______________ ______ ^Greenish gray SHALE, fractured, dry to moist. Medium to coarse greenish gray SANDSTONE, micaceous, darker gray \thin layers, dry. II Bentonite Seal 0G029 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method July 24, 2002 July 25, 2002 4" Air Coring Continuous DRMW-19B (page 6 of 7) Company Northing <WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256212.512' : 1381381.714' : Vernon : Lucinda Tilton t0o) u_ Surf. Elev. C(UL Q 125- O X Q<. DESCRIPTION XO Thin layer of greenish gray SHALE, fractured, dry to moist. Fine greenish gray SILTSTONE, micaceous, dry. Fine to medium greenish gray SANDSTONE, micaceous, dry. Well: DRMW-19B Elev.: 880.270' PVC Bentonite Seal 130- Greenish gray SHALE, dry, trace mica. Greenish gray sandy SILTSTONE, micaceous, dry. 135140- Greenish gray medium to coarse SANDSTONE, micaceous, some thin darker grey layering, dry to moist. Screen -- Sand 145150- SAA with some greenish gray SHALE intermixed. 000290 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-19B July 24. 2002 July 25. 2002 4" Air Coring Continuous (page 7 of 7) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256212.512' : 1381381.714' : Vernon : Lucinda Tilton Surf. Elev. a> O 150- 155 Well: DRMW-19B O Elev.: 880.270' X CL < DESCRIPTION a CD Greenish gray fine sandy SILTSTONE, micaceous, dry. Greenish gray and reddish brown SHALE, trace mica, dry to moist. Greenish gray and reddish brown SHALE, sllckensldes, yellow and purple mottling, moist to wet, fractured. Reddish brown SHALE, clayey sllckensides, trace yellow mottling, moist to wet. - Sand or Bent Greenish gray SILTSTONE, sandy, micaceous, dry Greenish gray fine to coarse silty SANDSTONE, grains coarsen with depth, micaceous, dry to moist, dark grey thin layering. 160 TD hole at 160'. 165- 170- 175- 000231 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-20B July 22, 2002? July 23, 2002 4" Air Coring Continuous (page 1 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256558.549' : 1381111.677' : Vernon : Lucinda Tilton Surf. Elev. aQ>. O 0- O X CL <a. DESCRIPTION o Casing installed to 19'. Bedrock hit immediately, SHALE? Well: DRMW-20B Elev.: 867.070' 5- 10- 15No recovery - SHALE when installing casing above 20- -- Casing -PVC -Grout 25- 000232 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-20B : July 22. 2002? : July 23. 2002 : 4" : Air Coring : Continuous (page 2 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256558.549' : 1381111.677' : Vernon : Lucinda Tilton a> uCD. Surf. Elev QCU. O 25- O X 0. o DESCRIPTION Well: DRMW-20B Elev.: 867.070' 3035404550- Clayey reddish SHALE, slickensides, fractured, moist to wet. Fine grained, silty, greenish gray SANDSTONE, slickensides, micaceous, dry, little red mottling. -PVC ^ -- Grout Red SILTSTONE, with some gray siltstone, trace fracturing and sandy element, orangish mottling, dry to moist. Greenish gray sandy SILTSTONE, slickensides, red and orange mottling, dry, trace thin beds of orange @ bottom. Fine to medium SANDSTONE, greenish gray, some thin beds of orange, micaceous, dry, orange mottling. Fine to medium greenish gray SANDSTONE, micaceous, dry, silty by 48.5', red mottling, moist to wet with little reddish beds below that point. 4)00233 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-20B July 22, 2002? July 23, 2002 4" Air Coring Continuous (page 3 of 6) Company Northing (WV St PI) Easting Coord. Survey By logged By : Duncan Bros : 256558.549' : 1381111.677' : Vernon : Lucinda Tilton Surf. Elev. Q- a 50- 55- O X a. DESCRIPTION O Medium to coarse greenish gray SANDSTONE, some darker grey thin layers, micaceous, orangish mottling, moist. Fine to medium silty greenish gray SANDSTONE, with some reddish layers, a lot of red mottling, micaceous, moist. Grenish gray SHALE (some brownish red), clayey, moist to wet, trace mica. Well: DRMW-20B Elev.: 867.070' Red SHALE, with little grey shale @ top, abundant slickensides, which were very defined, fractured, yellow mottling increases with depth, wet. 60- -PVC -Grout 65- SAA with yellow and dark red mottling. 70- SAA with some green/gray SHALE. 75- 000294 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-20B July 22, 2002? July 23, 2002 4" Air Coring Continuous (page 4 of 6) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 256558.549' : 1381111.677' : Vernon : Lucinda Tilton Ocu) Surf. Elev. Q. CD Q 75- g x 0. < a: o DESCRIPTION Well: DRMW-20B Elev.: 867.070' Greenish gray SHALE, with some red shale, slickensides, wet. Fine to medium silty greenish gray SANDSTONE, micaceous, red mottling, dry to moist, thin darker grey layering with thin layers of greenish gray SHALE. 80- Greenish gray SHALE, fractured, slickensides, wet. 85-PVC SAA with some reddish SHALE, very fractured. Reddish brown SHALE, trace gray shale, fractured, slickensides abundant, very mottled with yellow and purplish red all throughout, wet. -Grout 90- 95- 100- SAA with less mottling, Greenish gray shale from 98.5-99.5'. Greenish gray SHALE with slickensides, red mottling, clayey, moist to wet below this. 4 )0 0 2 0 5 000296 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-20B July 22, 2002? July 23, 2002 4" Air Coring Continuous (page 6 of 6) Company Northing (WV St PI) Easting Coord Survey By Logged By : Duncan Bros : 256558.549' : 1381111.677' : Vernon : Lucinda Tilton u<o_D> Surf. Elev. Q. <D O 125 O X O. o DESCRIPTION Well: DRMW-20B Elev.: 867.070' 130- -Screen -- Sand 135140- SAA with thin layers of greenish gray SHALE, slickensides, reddish \mottling.____________________________________________________ Medium to coarse greenish gray SANDSTONE, micaceous, thin dark grey layers, dry to moist. Fine grained greenish gray SILTSTONE, dry. Greenish gray and brownish red SHALE, slickensides, yellow and reddish mottling, moist. Reddish brown SHALE, slickensides, yellow and brown mottling, moist to wet. -Sand or Bent. 145- TD hole at - 143.5, setting screen at 134'. 15 0 - 00297 004)238 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 DRMW-21A/B Date Started Date Completed Well Diameter Drilling Method Sampling Method : July 31,2002 : August 7,2002 (B) : 2" (A)/4"(B) : Air Coring : Continuous (page 2 of 8) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 257118.637' : 1379354.839' : Vernon : Lucinda Tilton u0a_>) Surf. Elev. C<uL a 25- O X0. CD DESCRIPTION Well: DRMW-21A/B Elev.: 705.600' 30Greenish gray SHALE, very competent, dry. Reddish brown SHALE, sandy with some greenish gray shale, slickensides, dry to moist, some yellow mottling, some fractures. Greenish gray fine to medium SANDSTONE, micaceous, dry. 35- -PVC (21B) -- Grout 40- Greenish gray sandy SHALE, trace mica, dry to moist. Greenish gray and reddish brown SHALE, dry to moist. 4 5 - Reddish brown clayey SHALE, with some greenish gray shale, slickensides, moist. 50- 0 1)0 2 5 9 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-21A/B : July 31, 2002 : August 7,2002 (B) : 2" (A)/4"(B) : Air Coring : Continuous (page 3 of 8) Company Northing (W V St PI) Easting Coord. Survey By Logged By : Duncan Bros : 257118.637' : 1379354.839' : Vernon : Lucinda Tilton Q. CD Q 50- Surf. Elev. O X CC<CDLt DESCRIPTION SHALE with yellow and red mottling, moist to wet. Well: DRMW-21A/B oO<>D Elev.: 705.600' CD DC 55- 60657075- Reddish brown SHALE, with some greenish gray shale, slickensides, fracturing increasing with depth, yellow and purplish mottling, moist to wet. SHALE, very fractured, clayey, abundant yellow mottling, making it look yellow brown. Dark grey to black SHALE, slickensides, little fracturing, moist. Dark greenish grey SHALE, slickensides, moist, little fracturing. -PVC (21B) - Grout SHALE, some fracturing and abundant yellowish brown mottling. SHALE, with trace yellow brown mottling. 000300 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-21A/B : July 31,2002 : August 7,2002 (B) : 2" (A)/ 4"(B) : Air Coring : Continuous (page 4 of 8) Company Northing (W V St PI) Easting Coord. Survey By Logged By : Duncan Bros : 257118.637' : 1379354.839' : Vernon : Lucinda Tilton Surf. Elev. a> Q 75- O X 0. c o DESCRIPTION Well: DRMW-21A/B Elev.: 705.600' Greenish gray SHALE, slickensides, little red brown mottling, moist to wet, fractured. 80- Greenish gray sandy SHALE, little slickensides, little fractured, trace brown mottling, dry. 85- -PVC (21B) -Grout 90- greenish gray sandy fine SILTSTONE, micaceous, dry. Greenish gray sandy SHALE, slickensides, dry, trace fractures. 95- 100- U0030:l URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-21A/B July 31.2002 August 7,2002 (B) 2" (A)/ 4"(B) Air Coring Continuous (page 5 of 8) Company Northing (WV St PI) Easting Coord. Survey By Logged By Duncan Bros 257118.637' 1379354.839' Vernon Lucinda Tilton Q<U. Q 100- Surf. Elev. O X0. DESCRIPTION o SHALE, w/ only trace sand, some red shale, very fractured, moist to wet. Greenish gray and reddish brown SHALE, with yellow mottling, slickensides, fractured, moist to wet. Well: DRMW-21A/B Elev.: 705.600' 105- SHALE, with little purplish red mottling, becomes more clayey with depth. 110115 -- 120125- ^Greenish gray sandy SHALE, with some red shale, dry. Greenish gray and reddish brown clayey SHALE, with dark grey and i yellowish brown mottling, dry to moist, slickensides. Greenish gray SHALE, slickensides, trace mica, dry to moist. Greenish gray and reddish brown SHALE, abundant yellowish and purple mottling, fractured, dry to moist, slickensides. Greenish gray sandy SHALE, micaceous, dry. Greenish gray fine to coarse SANDSTONE, micaceous, some darker gray thin layering, little thin beds of greenish gray SHALE. -PVC (21B) -G rout Greenish gray medium to coarse SANDSTONE, micaceous, trace thin lenses of grey shale, dry to moist. 000302 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-21A/B July 31. 2002 August 7,2002 (B) 2" (A)/ 4"(B) Air Coring Continuous (page 6 of 8) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros : 257118.637' : 1379354.839' : Vernon : Lucinda Tilton 000303 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project # 18983634.00026 DRMW-21A/B Date Started Date Completed Well Diameter Drilling Method Sampling Method : July 31, 2002 : August 7,2002 (B) :2 -< A )/4 "(B ) : Air Coring : Continuous Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros . 257118.637' : 1379354.839' : Vernon : Lucinda Tilton 000304 URS DuPont Corporate Remediation Group Washington Works Consent Order Well Installation Dry Run Landfill Project# 18983634.00026 Date Started Date Completed Well Diameter Drilling Method Sampling Method DRMW-21A/B : July 31, 2002 : August 7,2002 (B) : 2" (A)/ 4"(B) : Air Coring : Continuous (page 8 of 8) Company Northing (WV St PI) Easting Coord. Survey By Logged By : Duncan Bros :257118.637' : 1379354.839' : Vernon : Lucinda Tilton Q0). Q 175- Surf. Elev g XQ. < a: o TD hole at 177'. DESCRIPTION Well: DRMW-21A/B 0>) Elev.: 705.600' 8 oac) -Sand 180- 185- 190- 195- 200- 000305 Bariev Mill Plaza. Building 27 Lancaster Pike & Route 141 000306 Wilmington, PE 19805