Document 06moq2OoavMxxBrJ73Zr6LXRn

NPDES Compliance Inspection Report Federal Highway Administration Denali National Park, AK NPDES Permit Tracking Number # AKR10F00I Inspection Date: July 1, 2024 Prepared by: Katrina Chambon U.S. Environmental Protection Agency, Region 10 Enforcement & Compliance Assurance Division Water Enforcement & Field Branch Surface Water Enforcement Section Inspector Signature/Date: Supervisor Signature/Date: Contents I. Facility Information ............................................................................................................ 3 II. Inspection Information........................................................................................................ 3 III. Permit Information.............................................................................................................. 4 IV. Facility Background............................................................................................................ 4 V. Inspection Chronology........................................................................................................ 5 VI. Opening Conference ........................................................................................................... 5 VII. Site Review ..................................................................................................................... 5 VIII. File Review ..................................................................................................................... 7 IX. Areas of Concern ................................................................................................................ 7 A. Discharge beyond the construction site ..................................................................7 X. Closing Conference....................................................................................8 ATTACHMENT A - Project Location ATTACHMENT B - Staging Area ATTACHMENT C - Photograph Log ATTACHMENT D - Material Flow Map ATTACHMENT E - Turbidiy Montioring Locations ATTACHMENT F Turbidiy Sample Results 2 [Unless otherwise noted, all details in this inspection report were obtained from conversations with Mr. David Harvey and Mr. Cyrus Bullock with Federal Highway Administration (FHWA) and Mr. Alex Baham, Mr. Benjamin Lamirand, and Mr. Alexander Johnson with Granite Construction or from observations made during the inspection.] I. Facility Information Facility Name: Polychrome Area Improvement Facility Address: Milepost 45.4 Denali National Park, Alaska 99755 Facility Operator: Federal Highway Administration Western Federal Lands Highway Division 610 East 5th Street Vancouver, Washington 98861 Facility Owner: National Park Service Denali National Park and Preserve PO Box 9 Denali Park, Alaska 99755 Facility Contact(s): Cyrus Bullock Environmental Protection Specialist cyrus.bullock@dot.gov 208-629-2434 Latitude/Longitude: N 63.53639 W - 149.81744 NPDES Tracking Number: AKR10F00I NAICS Code(s): Not Applicable SIC Code(s): Not Applicable Facility Size: 13 acres II. Inspection Information Inspection Date: July 1, 2024 Inspector(s): Katrina Chambon EPA Region 10, ECAD / SWES Mark Jen EPA Region 10, ECAD / SWES 3 Arrival Time: Departure Time: Weather: 03:30 PM 7:20 PM Mostly cloudy; moderate temperature Purpose: To evaluate compliance with the requirements of the Clean Water Act and the National Pollutant Discharge Elimination System (NPDES) Construction General Permit. III. Permit Information Polychrome Area Improvement (hereinafter referred to as the "Facility") is a construction project located at milepost 45.4 along the Denali Park Road in Denali National Park, Alaska. The Federal Highway Administration (FHWA) is the operator with Granite Construction as the co-permittee. The current version of the Construction General Permit (CGP) became effective on February 17, 2022, and is set to expire on February16, 2027. The Facility submitted a Notice of Intent on April 25, 2023. The Facility submitted a modified NOI on April 23, 2024, to update the project end date from October 15, 2025 to October 31, 2026. IV. Facility Background According to the Facility's Stormwater Pollution Prevention Plan (SWPPP), dated April 14, 2023, the Polychrome Area Improvement Project is located at milepost 45.4 along the Denali Park Road in the Denali National Park and Preserve. The primary objective is to reinstate access, via a 475-foot bridge, to the remainder of the park road. The road was impacted by the ongoing "Pretty Rocks Landslide," which descends toward the East Fork Toklat River. The project required approximately 60,000 cubic yards (cy) of excavation on the west end of the project to realign the road for the new bridge. The disposal area for the material is in the land slide area. The project encompasses approximately 13 acres. On June 10, 2024, the FHWA reported that colluvium material in the disposal area was beginning to thaw and flow down the mountain, outside the boundaries of the disposal site, towards the East Fork of the Toklat River and towards wetlands located adjacent to the Toklat River. V. Inspection Chronology To confirm on-site availability and logistics, this inspection was announced on June 18, 2024. I called and spoke with Ms. Jennifer Corwin, Environmental Protection Specialist and the former point of contact for the project. Ms. Corwin is listed on the initial Notice of Intent (NOI) as the operator/point of contact and she was filling in for Mr. Cyrus Bullock, the current point of contact. During the call, I introduced myself and discussed that I had been asked to conduct an on-site CWA NPDES inspection of the Polychrome 4 Area Improvement. I informed Ms. Corwin the inspection was to assess compliance with coverage under the 2022 CGP and that the inspection will consist of an opening conference, a records review, a tour of the facility and a closing conference. A follow-up email was sent June 20, 2024, to confirm the inspection and to get more information on the logistics. I was joined on the inspection by fellow EPA Region 10 Inspector Mark Jen. Mr. Jen and I arrived on-site at approximately 3:30PM, we entered the job site trailer and were greeted by Mr. David Harvey, Mr. Cyrus Bullock, Mr. Alex Baham, Mr. Benjamin Lamirand, and Mr. Alexander Johnson. Following our initial introductions, I presented my EPA credentials and discussed the purpose and expectations of the inspection and provided my business card. We had a brief discussion regarding the project's general timeline and recent activities. Mr. Harvey explained that the current phase of the project was building the abutments for the bridge and installing thermosiphons. Mr. Harvey has been involved on the project site since it broke ground in early May 2023. The inspection consisted of an opening conference, a walk-through of the Facility's general operations and stormwater areas, a records review, and ended with a closing conference. We were accompanied by FHWA and Granite Construction representatives throughout the inspection. VI. Opening Conference Opening conference began at 3:40 PM. The opening conference was held with FHWA and Granite Construction representatives shortly after our arrival. We had our initial introductions; Mr. Mark Jen and I presented our inspector credentials and discussed the purpose and scope of the inspection. During the opening conference Mr. Harvey and Mr. Baham provided a general background of the Facility operations, current staffing, and general stormwater management responsibilities. VII. Site Review The Facility's primary activity is the removal of material to build a bridge across the land slide area to allow access to the remainder of the park road. Equipment onsite included dozers, excavators, loaders, a roller, crane, rock trucks, forklift, mobile grout plants, and a fuel truck. There were three fuel tanks onsite, one 18,000-gallon diesel, one 6,000gallon of diesel, and one 5,000-gallon of gasoline. According to the Facility's SWPPP, potential pollutants associated with the Facility's activities include trash, debris, pH, metals, sediment, nutrients, and oil and grease. Best management practices (BMP) used onsite include silt fences, woodchip silt socks, reclaimed asphalt pavement stabilization, coconut matting, duck ponds, fuel containment, and rocks for ditch lining. Operations at the site occurs 7 days a week from 7am to 5pm. Winter shut down will be in midOctober. There are two man-camps, two staging areas located at milepost 5 and 44.8 and four material staging areas located at milepost 44, 45.1, 45.6, and 53. NOI postings are located at milepost 5 and at the East Fork Toklat Bridge. 5 We began the facility walkthrough with FHWA and Granite Construction representatives starting at the east side of the project area. We observed the material that slid towards the East Fork of the Toklat River. (Photo 1, Photo 2, Photo 3, and Photo 4). Mr. Baham discussed that approximately 70,000 cy of excavation was required on the west end of the project to realign the road for the new bridge. Mr. Baham stated that approximately 15,000 to 20,000 cy consisted of frozen colluvium and the remaining material was shot rock that needed to be drilled and blasted. A portion of the shot rock material was used to develop and maintain an access road across the slide. A loader was used to dispose the colluvium of over the edge of the road in the "Pretty Rocks Landslide" area. No initial erosional controls were used for the colluvium due to the unstable slope. The movement of the colluvium was discovered in late May and in the first week of June the colluvium liquified and started moving. It is estimated that the 15,000 to 20,000 cy of material has eroded and slid on the slide area towards wetlands and a braided bed with standing water. No BMPs were used to stop the flow due to the steep slope making for unsafe conditions. Mr. Baham stated that turbidity monitoring was being conducted twice daily and that no turbidity readings were found to exceed the turbidity limits of 50 nephelometric turbidity units (NTU) above background (Attachment E). Next, I requested that Mr. Johnson provide a tour of the Facility and show us what he does when he conducts inspections. Mr. Johnson stated that there is no rain gauge onsite, and that weather information is being gathered by the National Park Service's Toklat River weather station. He also stated that there have been no reportable spills and that spill kits are located throughout the site (Photo 7). First, we inspected equipment located on the east side of the project area to check for puddles and leaks, no leaks were identified (Photo 5 and Photo 6). Next, we inspected the Facility to look for trash and debris, which is collected daily and disposed of at the landfill located outside of the park (Photo 8). Trash and debris were not observed. At the time of the inspection, thermosiphons were being installed next to the east abutment, which require the use of drill rigs (Photo 9 and Photo 10). No concerns were identified with the installation of the thermosiphons. We walked to the west portion of the facility to inspect the mobile grout plant and to check the erosional control blanket installed on a rock face. Grout plants include a combination of a mixer and agitator, eco-pans, and secondary containment. Eco-pans are designed to minimize concrete washout spillage and to decant the water The water is then pumped into totes and the grout is allowed to dry for disposal offsite. The secondary containment was observed and appeared to be working as intended (Photo 11, Photo 12, Photo 13, Photo 14 and Photo 15). We walked to the staging area located to the west of the Facility where an ice bulb is located. The ice bulb was discovered when material for the site was being excavated. The ice bulb was excavated and moved to the staging area and covered with rocky material to prevent to ice from melting at a rapid rate (Photo 16 and Photo 17). Straw wattles and silt fences were observed and appeared to be working as intended (Photo 18, Photo 19, and Photo 20) Next, we toured the staging area located at milepost 44.8. The constructed pad did not show signs of erosion. Straw wattles and silt fences were observed and appeared to be working as intended. No spills or leaks were observed, and the port-a-potty was secured 6 to the ground (Photo 21, Photo 22, Photo 23, Photo 24, and Photo 25). Finally, we returned to the main office and staging area located at milepost 27.2. We observed the diesel and gasoline fuel tanks in a constructed secondary containment area. Labeled 55-gallon drums were observed within the secondary containment. No sheen was visible within the secondary containment area. Mr. Baham stated that if a sheen were to be observed, absorbent pads would be used to capture the sheen. Also available for use is a carbon filter unit. No sheens were observed in the secondary containment area and the there was no pumping of water. If water needs to be pumped from the secondary containment, discharge will be to the ground (Photo 26, Photo 27, Photo 28, Photo 29, Photo 30, Photo 31, and Photo 32). File Review The following documents were reviewed as part of this inspection: 2022 Construction General Permit Notice of Intent (NOI) - The Facility's initial NOI was reviewed prior to the inspection. It was certified by Mr. Scott Smithline on April 25, 2023. Modified NOI dated April 23, 2024, updating the end project date from October 15, 2025, to October 31, 2026. EPA's authorization email dated May 10, 2023 SWPPP SWPPP amendments Site Inspection Reports - The permittee conducts weekly inspections. The inspections are conducted by Mr. Johnson or by Mr. Baham on Wednesdays. The inspections reports are signed by Mr. Harvey and Mr. Michael Wheatly. Corrective action logs Grading and stabilization logs Employee training logs Delegation of Authority Spill log 7 VIII. Areas of Concern Observations during the inspection identified the following areas of concern. A. Minimize steep slope disturbances On June 10, 2024, the FHWA reported that colluvium material in the disposal area was beginning to thaw and flow down the mountain, outside the boundaries of the disposal site, towards the East Fork of the Toklat River. The discharge of colluvium was observed at the time of the inspection and the discharge appeared to be stable. Permit part 2.2.7 Minimize steep slope disturbances. IX. Closing Conference Following the walk-through and file review, a closing conference was held with FHWA and Granite Construction representatives where we discussed our observations, the areas of concern, and next steps regarding inspection report transmittal. We thanked them for their time and cooperation with the inspection. Closing conference concluded at 7:20PM. 8