Document R0GV4pjx5EXyXoKXgqr8G4ya

Project No. 421167 January 1988 Final Report Endatigerment Assessment .. Brio Refining Inc. and Dixie Oil Processors Site Friendswood, Texas prepared foe Brio Task Force __ In Fulfillment Of Consent Order Requirement? ' Docket No. GERCLA 3ZI-9-85 RSV 0018423 ENDANGERHEMT ASSESSMENT BRIO REFINING INC. AND DIXIE OIL PROCESSING SITE FRIENDSWOOD, TEXAS Prepared for: BRIO TASK FORCE Prepared by: IT CORPORATION Project No. 421167 January 1988 RSV 0018424 TABLE OF CONTENTS 1.0 INTRODUCTION 2.0 SITE HISTORY AND CHARACTERIZATION 2.1 SITE DESCRIPTION AND HISTORY 2.1.1 Site Location 2.1.2 Site History 2.1.2.1 Operations at the Brio Refining Site 2.1.2.2 Operations at the Dixie Oil Processors Site 2.1.3 History of Site Investigations Prior to the RI 2.2 SITE CHARACTERIZATION 2.2.1 Scope of Work for RI and SRI 2.2.2 Sumsary of Chemical Analytical Data and Statistics 2.2.3 Quality andValidity of the Chemical Data 2.2.4 Occurrence and Distribution ofConstituents 2.2.4.1 Ambient Air 2.2.4.2 Surface Soils and Sediments 2.2.4.3 Ground Water 2.2.4.4 Surface Water 2.3 SUMMARY 3.0 ENVIRONMENTAL FATE ANDTRANSPORT 3.1 PHYSICAL AND CHEMICAL CHARACTERISTICS OFTHE IDENTIFIED COMPOUNDS 3.2 MIGRATION CHARACTERISTICS OF THE PRINCIPAL CONSTITUENTS 3.3 SUMMARY 4.0 HAZARD IDENTIFICATION 4.1 SELECTION OF THE INDICATOR CHEMICALS 4.1.1 Inocganlc Compounds 4.1.2 Carcinogenic PNAs 4.1.3 Non-Carcinogenic PNAs 4.1.4 Volatile Organic Compounds PAGE 1-1 2-1 2-1 2-1 2-2 2-4 2-5 2-5 2-6 2-6 2-7 2-8 2-9 2-9 2-9 2-11 2-13 2-13 3-1 3-2 3-3 3-5 4-1 4-1 4-3 4-5 4-5 4-6 RSV 0018425 TABLE OF CONTENTS (PAGE 2 OF 3) 4.1.4.1 Monocyclic Aromatic Hydrocarbons 4.1.4.2 Halogenated Aromatic Hydrocarbons 4.1.4.3 Halogenated Aliphatic Hydrocarbons 4.1.4.4 Chloroethers 4.1.4.5 Phthalate Esters 4.2 SUMMARY OF INDICATOR CHEMICALS 4.3 CARCINOGENICITY AND TOXICITY OF THEINDICATOR CHEMICALS 4.3*1 Carcinogenicity Evaluation 4.3*2 Subchronic and Chronic Toxicity 4.3.3 Acute Toxicity 4.3.4 Developmental and Reproductive Toxicity 4.3*5 Dose-Response Relationships 4.3*6 Epidemiological Evidence 4.4 SUMMARY 5.0 EXPOSURE ASSESSMENT 5.1 RECEPTOR DEFINITION 5.1*1 Land Use and Demographics 5.1.2 Ecology 5.2 EXPOSURE PATHWAYS 5.2.1 Ground Water Discharge to Mud Gully 5*2.2 Potential Effects on Drinking WaterSupplies 5.2.3 Flow from the NSC2 to the Fifty-FootSand 5.2.4 Sediment or Solute Transportin Runoff to Mud Gully 5*2.5 Volatile Emissions 5.2.6 Soil Ingestion and Dermal Exposure 5*2.7 Faults 5*2.8 Pipeline Routes 5.3 SUMMARY 6.0 CURRENT RISK CHARACTERIZATION (RISK AND IMPACT EVALUATION) 6.1 AMBIENT AIR 6.1.1 Estimation of the Receptor Ambient Air Concentrations (Exposure Level) 4-6 4-7 4-7 4-8 4-8 4-9 4-9 4-9 4-10 4-12 4-12 4-13 4-14 4-14 5-1 5-1 5-2 5-3 5-3 5-4 5-4 5-5 5-11 5-11 5-11 5-12 5-12 5-13 6-1 6-2 6-2 RSV 0018426 TABLE OF CONTENTS (PAGE 3 of 3) 6.1.2 Duration and Frequency of Exposure 6.1.3 Risk Characterization 6.1.3.1 Carcinogenic Potency 6.1.3.2 Ambient Air Risk Characterization 6.1.4 Suirmary of Air Pathway Risk Assessment 6.2 DERMALCONTACT AND INGESTION OF SEDIMENTS AND SURFACE SOILS 6.2.1 Mud Gully Sediments ' 6.2.2 Off-Site Surface Soils-Ingestion andDermal Contact 6.2.3 On Site Soil/Sediment Ingestion 6.2.4 Suncnary of Ingestion and Dermal Contact Pathway Risk Assessment 6.3 GROUNDWATER PATHWAY 6.3.1 Monitor Wells and Pits 6.3.2 Discharge of NSCZ to Mud Gully 6.3.3 Stream Flow in Mud Gully 6.3.4 Dilution Scenarios 6.3.5 Evaluation of Effects on Aquatic Biota 6.3.6 Fifty-Foot Sand Groundwater 6.4 SUMMARY AND CONCLUSIONS 7.0 FUTURE RISK CHARACTERIZATION AND MANAGEMENT 7.1 TARGET LEVELS FOR SOILS AND SEDIMENTS 7.1.1 Non-Carcinogenic PNAs 7.1.2 Carcinogenic PNAs 7.1.3 Volatile Compounds 7.2 TARGET LEVELS TO PROTECT AIR QUALITY 7.3 TARGET LEVELS FOR PROTECTION OF AQUATIC LIFE 7.4 TARGET LEVELS OF ORGANIC CONSTITUENTS IN THEFIFTY-FOOT SAND 7.5 SUMMARY AND CONCLUSIONS 8.0 SUMMARY AND CONCLUSIONS REFERENCES 6-4 6-4 6-4 6-5 6-5 6-5 6-6 6-6 6-7 6-8 6-9 6-9 6-10 6-11 6-12 6-12 6-14 6-14 7-1 7-2 7-3 7-3 7-3 7-4 7-5 7-6 7-6 8-1 BRO/EndAssToCr RSV 0018427 V LIST OF APPENDICES APPENDIX A SUMMARIZED CHEMICAL ANALYTICAL RESULTS, BRIO/DOP SITES APPENDIX B POTENTIAL SITE RECEPTORS APPENDIX C MODEL OF LEAKAGE TO FIFTY-FOOT SAND APPENDIX D REGRESSION ANALYSIS, STATISTICAL OUTPUT APPENDIX E CARCINOGENIC RISK CALCULATIONS FOR AMBIENT AIR PATHWAY APPENDIX F PROBABLE AND UPPERBOUND EXPOSURE SCENARIOUS FOR SOILS/SEDIMENTS AT BRIO AND DIXIE SITES APPENDIX G APPENDIX H SOIL INGESTION AND SKIN ABSORPTION SCENARIOS NON-CARCINOGENIC RISK CALCULATIONS QUANTIFICATION OF POTENTIAL RISKS ASSOCIATED WITH INGESTION OF GROUNDWATER FROM THE FIFTY-FOOT SAND AQUIFER APPENDIX I EVALUATION OF HEALTH RISKS ASSOCIATED WITH HEXACHLOROBENZENE IN PIT BACKFILL AT THE DOP SITE APPENDIX J TOTAL HAZARD INDEX APPENDIX K EPIDEMIOLOGICAL STUDIES OF HAZARDOUS WASTE SITES BRO/EndAssToCr RSV 0018428 LIST OF FIGURES FIGURE NO.TITLE 2-1 REGIONAL SITE LOCATION - BRIO AND DOP SITES 2-2 SITE VICINITY - BRIO AND DOP SITES 2-3 SITE PLAN AND FEATURES - BRIO AND DOP SITES 5-1 HYPOTHETICAL POTENTIAL EXPOSURE PATHWAYS - BRIO AND DOP SITES 5-2 HEAD DIFFERENCE BETWEEN NSCZ AND FIFTY-FOOT SAND (10/24/86) 5-3 SURFACE WATER DRAINAGE PATTERNS RSV 0018429 V LIST OF TABLES TABLE NO. 2-1 3-1 4-1 4-2 4-3 4-4 4-5 4-6 4-7 4-8 4-9 . 4-10 6-1 6-2 6-3 6-4 6-5 ___________ ___________ DESCRIPTION SUMMARY OF ORGANIC AND INORGANIC COMPOUNDS FOUND AT THE BRIO/DOP SITE PHYSICAL CHEMICAL, AND ENVIRONMENTAL FATE PROPERTIES OF BRIO/DOP CONSTITUENTS PHYSICAL/CHEMICAL/TOXICOLOGICAL RANKING OF POTENTIAL INDICATOR CHEMICALS FOR PIT"'MATERIALS PHYSICAL/CHEMICAL/TOXICOLOGICAL RANKING OF POTENTIAL INDICATOR CHEMICALS--SUBSOIL AND WASTEWATER TREATMENT SYSTEM SLUDGES PHYSICAL/CHEMICAL/TOXICOLOGICAL RANKING OF POTENTIAL INDICATOR CHEMICALS--RUNOFF TO MUD GULLY AND MUD CULLY SEDIMENT PHYSICAL/CHEMICAL/TOXICOLOGICAL RANKING OF POTENTIAL INDICATOR CHEMICALS--CONSTITUENTS PRESENT IN THE NSC2 CARCINOGENICITY PARAMETERS FOR INDICATOR CHEMICALS CARCINOGENICITY DATA AND WEIGHT OF EVIDENCE RATINGS FOR INDICATOR CHEMICALS EPA WEIGHT-OF-EVIDENCE CATEGORIES FOR POTENTIAL CARCINOGENS CHRONIC TOXICITY PARAMETERS FOR THE INDICATOR CHEMICALS BRIO/DOP SITE ACUTE TOXICITY PARAMETERS FOR THE INDICATOR CHEMICALS BRIO/DOP SITE CHARACTERIZATION OF DEVELOPMENTAL REPRODUCTIVE TOXICITY ESTIMATION OF CARCINOGENIC POTENCY FACTORS FOR CARCINOGENIC POLYCYCLIC AROMATIC HYDROCARBONS CALCULATED AIR PATHWAY CANCER RISK AT OFF SITE RECEPTORS TOTAL HAZARD INDEX ASSOCIATED WITH INGESTION/DERMAL ABSORPTION OF SURFACE SOILS/SEDIMENTS TOTAL CANCER RISK ASSOCIATED WITH INGESTION/DERMAL ABSORPTION OF SURFACE SOILS/SEDIMENTS NON-CARCINOGENIC PNA CONCENTRATION IN SOIL, (BASED ON SHALLOW TRENCH DATA COLLECTED AT BRIO AT 2.5 FOOT DEPTH) RSV 0018430 TABLE NO. 6-6 6-7 6-8 6-9 6-10 7-1 7-2 7-3 7-4 LIST OF TABLES (PAGE 2 OF 2) DESCRIPTION INDICATOR CHEMICAL CONCENTRATIONS IN THE NSCZt BRIO REFINING SITE AQUATIC TOXICITY DATA FOR INDICATOR CONSTITUENTS, BRIO/DOP SITE .PREDICTED MUD GULLY CONCENTRATIONS AFTER DILUTION OF NSCZ AND PITS B, D, AND E CONTRIBUTIONS VS. AQUATIC TOXICITY LEVELS FOR FRESH WATER FISH, BRIO/DOP SITE, FRIENDSWOOD, TEXAS PREDICTED MUD GULLY CONCENTRATIONS AFTER DILUTION OF NSCZ CONTRIBUTIONS FROM 13A AND 18A VS. AQUATIC TOXICITY LEVELS FOR FRESH WATER FISH, BRIO/DOP SITE, FRIENDSWOOD, TEXAS SUMMARY OF CURRENT RISK CHARACTERIZATION APPROPRIATE TARGET LEVELS FOR SOILS AND SEDIMENTS TO ACHIEVE INDENTIFIED PUBLIC HEALTH AND ENVIRONMENTAL PROTECTION GOALS BASED ON INGESTION AND DERMAL CONTACT TARGET SOIL LEVELS BASED ON THE PUBLIC HEALTH AND ENVIRONMENTAL PROTECTION GOAL OF PROTECTION OF THE AIR EXPOSURE PATHWAY TARGET NSCZ LEVELS BASED ON THE PUBLIC HEALTH AND ENVIRONMENTAL PROTECTION GOAL OF PROTECTING AQUATIC ORGANISMS IN MUD GULLY TARGET LEVELS TO ACHIEVE PUBLIC HEALTH AND ENVIRONMENTAL PROTECTION GOALS IN THE FIFTY-FOOT SAND BRO/EndAssToCr RSV 0018431 RSV 0018432 ENDANGERKQTT ASSESSMENT BRIO/DOP SITE HARRIS COUNTY, TEXAS 1.0 INTRODUCTION The National Oil and Hazardous Substances Pollution Contingency Plan (NCP) (MO CFR Part 300) requires development of an Endangerment Assessment (EA) at sites listed on the National Priorities List (NPL) under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of I960 as amended by the Superfund Amendments and Reauthorization Act (SARA) of 1986. The objective of the EA is to identify possible risks to human health and the environment due to exposure to hazardous materials present in the environmental media at these sites. This EA is designed to Identify and evaluate those risks for two adjacent Superfund sites: the Brio Refining and Dixie Oil Processors (Brio/DOP) sites. This EA documents that determination of endangerment and serves as the basis for evaluating the alternative in the Feasibility Study (FS). In addition, the EA characterizes one of the selection criteria for the remedial alternatives, namely public health concerns. It establishes the site baseline condition and is an assessment of the risks represented by those baseline conditions assuming no future action. The principal guidance document used to prepare this EA is "The Endangerment Assessment Handbook", ICAIR Life Sciences Inc. U. S. Office of Waste Programs Enforcement, draft dated August 1985 (ICAIR, 1985). Specifically the scope and content of the EA include all of the data and information required in a Level 3 EA document (i.e., the most quantitative detail) as defined in Chapter 5 of the above citation. BRO/EndAssSIr 1-1 RSV 0018433 Other endangeraent assessment guidance documents, health risk assessment reports and references consulted in the preparation of this EA, include: Versar (1986) Superfund Exposure Assessment Manual, Draft, Washington, D.C.: U.S. EPA, Office of Emergency and Remedial Response. Contract No. 68-01-6871, draft dated January 14, 1986. EPA (1986) Superfund Public Health Evaluation Manual, Washington, D.C.: U.S. EPA, Office of Emergency and Remedial Response. Contract No. 68-01-7090 Task 7, EPA 540/1-86/060, October 1986, (prior drafts dated December 18, 1985 and May 22, 1985 were entitled Superfund Health As'sessment Manual). ICAIR, Life Systems Inc. (1985) Toxicology Handbook: Principles Related to Hazardous Waste Site Investigations, Draft, Washington, D.C.: Environmental Protection Agency, Office of Waste Programs Enforcement, Contract No. 68-01-7037, draft dated August 1985. EPA (1984) Endangerment Assessment Guidance, internal memorandum from Lee Thomas, EPA Administrator, to EPA Regional Administrators, Regions I-X. EPA (1985) Endangerment Assessment Guidance, Draft, memorandum from J. Winston Porter, EPA Asst. Administrator, dated September 20, 1985. EPA (1986) Guideline for Carcinogenic Risk Assessment (Federal Register, September 24, 1986). EPA (1986) Guideline for Exposure Assessment (Federal Register, September 24, 1986). EPA (1986) Guideline for Mutagenicity Risk Assessment (Federal Register, September 24, 1986). EPA (1986) Guideline for Assessment of Chemical Mixtures, (Federal Register, September 24, 1986). EPA (1986) Guideline for Assessment of Suspect Developmental Toxicants (Federal Register September 24, 1986). U.S. Interagency Staff Group on Carcinogens (1986) "Chemical Carcinogens: A Review of the Science and its Associated Principles", Environmental Health Perspectives. Vol. 67, pp. 201-282. RSV 0018434 1-2 Chapter 2 sumnarizes the characterization of the site as contained in the Remedial Investigation (RI) and Summary Remedial Investigation (SRI). It provides general site information and describes the location and physical setting. Past Tiistory of residuals and crude oil processing is described to give insight into the origin of chemical constituents detected in the various environmental media. Past investigations described in the RI were used as background information. The RI and SRI chemical analytical data are summarized in the context of the EA requirements. Occurrence and distribution of constituents of concern are described in order to focus on potential exposure pathways. In Chapter 3 the potential for mobility, transport, and environmental fate of the individual constituents found at the Brio/DOP site is presented, based on their chemical and physical properties and the site characteristics. The hazards associated with the site specific constituents are identified in Chapter 4. Chemicals of concern are selected to represent the hazards posed by the site on the basis of concentration levels, toxicity, frequency of detection as a measure of prevalence across the site in various media, and persistence in the environment. The site constituents are evaluated in terms of acute, subchronic, and chronic toxicity; carcinogenicity; mutagenicity; and potential health consequences. Chapter 5 describes the site-specific exposure assessment. Receptors, both human and environmental, are defined using appropriate descriptions. Pathways for potential exposure are postulated and evaluated for plausibility. Exposure concentrations, where appropriate for this pathway assessment, are calculated at the potential receptor locations for the postulated scenarios. Chapter 6 evaluates current risks resulting from existing site conditions. This analysis assumes that there will be no future change in transport and migration pathways. Chapter 7 considers future risks that might result from such changes in site conditions such as erosion of the cover on the existing pits, etc. Acceptable levels of chemical constituents are established for specific exposure pathways 1-3 RSV 0018435 by assuming that these pathways, while not posing a significant health risk now, may do so in the future. Appropriate clean up goals that adequately protect the public health and environment are established in Chapter 7. Interrisk comparisons, presented in Chapter 8, provide perspective associated with the calculated risk levels. The conclusions derived from the EA are presented in Chapter 9. RSV 0018436 1-4 RSV 0018437 2.0 SITE HISTORY AND CHARACTERIZATION The EA is designed to be a concise, self-contained document. Therefore, a short site description and history is presented in order to furnish relevant site background information. The site description presents the general characteristics of the site and its setting. The history of activities at Brio/DOP is intended to assist the reader in understanding how current site conditions developed. This EA covers two adjacent Superfund site locations: the Brio Refining (Brio) site and the Dixie Oil Processors (DOP) site. The site location and vicinity maps are shown in Figures 2-1, 2-2, and 2-3. The following section describes each site in terms of operational history and previous investigation results. 2.1 SITE DESCRIPTION AND HISTORY 2.1.1 Site Location The Brio and DOP sites are located in Harris County approximately 20 miles southeast of Houston, Texas. The sites are about 1.5 miles southwest of Interstate Highway 45 South (Gulf Freeway) at the Ellington Field exit. Friendswood is located approximately 1 to 2 miles to the south. As shown in Figure 2-2, the Brio and DOP sites are located north and south of Dixie Farm Road. For ease of reference, portions of both sites occurring north of Dixie Farm Road are designated "North", while those south of Dixie Farm Road are designated "South". The Brio North*and DOP North parcels are separated by a flood control ditch, a local tributary of Clear Creek designated as Mud Gully. The gully runs generally from north to south along the western boundary of the Brio property and discharges into Clear Creek. Clear Creek flows from west to east about one-half mile south of the site. Brio North is bordered to the northwest by Southbend Subdivision and to the northeast by Beamer Road. DOP North is BR0/EndAssS2-R RSV 0018438 2-1 v RSV 0018439 v RSV 0018440 Ds NM ScM IM C>IMt