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HomeMy WebLinkAboutPN_Voluntary CleanUp Scope of Work_20180803STEMEN ENVIRONMENTAL, INC. P.O. BOX 3644 LACEY, WASHINGTON 98509-3644 CONTR. LIC. #STEMEEI081J9 Telephone 360-438-9521 Fax 360-412-1225 April 23, 2018 RE: REMEDIAL AND CORRECTIVE ACTIONS PROJECT FOR THE COMMERCIAL PROPERTY LOCATED AT 3400 VALLEY ROAD, RENTON, WASHINGTON. TAX PARCEL #302305-906 A. OVERVIEW The subject property is composed of 5.65 acres (246,114 square feet) of commercially developed property located at 3400 East Valley Road, Renton, Washington. The King County Assessor’s Office lists the subject property as Tax Parcel #302305-9067. Based on the review of aerial photos, Polk Street Directories, knowledgeable individuals, and information obtained from the King County Assessor's Office, it appears that for approximately 64 years the subject property has been primarily occupied by an automotive wrecking yard and/or radiator shop. All automobile wrecking yard and/or radiator shop related operations have ceased on the subject property. All disabled vehicles, automotive parts, storage trailers and related equipment have been removed from the property. Currently the subject property and the on-site building are unoccupied. Recent environmental investigations of the surface and shallow subsurface soils on the subject property have confirmed the presence of total petroleum hydrocarbons, and/or volatile organic compounds at levels exceeding MTCA Method A Clean Up Levels for Industrial Properties. Primarily the adversely impacted soils are present at depths of 2 feet below ground surface (b.g.s.) or less on most of the property. The contaminated soils plume extends to greater depths on selected portions of the property. Initial groundwater samples obtained, using a truck mounted sampling probe, from selected locations on the subject property confirmed the presence of total petroleum hydrocarbons, volatile organic compounds and/or MTCA 5 Metals at MTCA Method A Clean Up Levels for Industrial Properties. A total of eight (8) groundwater monitoring wells were installed at selected locations throughout the subject property using a truck mounted rotary auger drill rig operated by Licensed Resource Protection Well Drillers. Discreet groundwater samples were obtained from the groundwater monitoring wells on two (2) seasonal groundwater monitoring events. Laboratory analyses results for the discreet groundwater samples report no presence of the contaminants of concern at levels exceeding MTCA Method A Clean Up Levels for Industrial Properties. 2 Based on groundwater elevation measurements obtained in the dryer season (lower groundwater elevations) the direction of groundwater flow is to the west, based on the elevations obtained during the wetter season (higher groundwater elevation) the direction of groundwater was to the northwest. Refer to Figures 1A and 1B for the Groundwater Elevation Maps. The purpose of the proposed remedial and corrective actions project is to excavate and remove all on-site soils that are adversely impacted by the contaminants of concern and to monitor the positive impacts of these actions on the groundwater and the environmental integrity of the subject property. Any solid waste debris encountered during the excavation and removal of petroleum and/or VOCs contaminated soils will be transported off-site to an appropriate off-site disposal facility. Summary of Work: B. REQUIRED PERMITS / APPROVALS  SEPA Issuance  NPDES Construction Stormwater General Permit  City of Renton Demolition Permit  City of Renton Civil Construction Permit (Clear and Grade & TESC Only) Prior to the commencement of activities on selected portions of the subject property/site, the above noted permits will be obtained. C. CLEANUP SEQUENCE / SCHEDULE 1. Anticipated Construction: Start July 2018 Complete October 2018 2. Contractor will post sign with name and phone number of ESC supervisor (May be consolidated with the required notice of construction sign). 3. Contractor will schedule a pre-construction meeting with the City of Renton Inspector and Engineer prior to any ground disturbing activity. 4. Contractor will flag or fence clearing limits and install perimeter erosion control measures including perimeter filter fabric fencing per approved grading plans. 5. Contractor will install stabilized construction entrances per approved grading plans. 6. The existing building will be demolished and associated services will be disconnected and abandoned under City Demolition Permit. a. Hazardous Materials Survey Report was completed by PBS Environmental on May 18, 2018. b. Hazardous Materials will be disposed of according to state regulations. c. All remaining demolition debris will be disposed at an approved disposal facility. 7. Cleanup sampling, excavation, disposal, and import of clean structural fill. a. Open Excavation work areas are intended to be between 5,000 -10,000 SF. b. Work areas will be excavated, sampled, and stockpiled. Samples will have a 48 hour turn-around. c. All contaminated soils (levels exceeding applicable cleanup levels) will be properly loaded and properly transported to either Waste Management’s Duwamish Reload Facility in Seattle or Republic Services facility in Seattle using 3 dump trucks. All soils will be transported under a properly issued manifest/waste disposal authorization. d. Once a work area is determined to be free of contamination the work area will be restored to existing grade to prevent re-contamination. Trucks will haul in clean structural material to fill the void. 8. The contractor will move sequentially through the entire property. 9. Paving materials that are encountered will be demolished and hauled to a local recycling facility. 10. The wetland buffer will be established with bioretention soil and hydroseeding to minimize growth of noxious weeds. 11. The contractor will enter the voluntary cleanup program. 12. No Further Action (NFA) letter will be requested. D. EQUIPMENT Conventional construction equipment will be used to conduct the site cleanup. An excavator and dump trucks are the primary equipment that will be used. It is anticipated that several trucks per day will be entering and exiting the site to haul off construction debris and import clean structural fill. Anticipate using the following: 2 – Case 160 (35000 lb) Excavators 1 – Case 580 K Excavator 1 – Midsize Dozer 1 – Front End Loader Dump Trucks with PUP trailers (Number depends on availability) Associated Water Pumps and Hoses Above Ground Temporary Water Storage Tank E. TOXICS CLEANUP PLAN 1. Demolition and removal of an approximately 4,000 square foot metal warehouse building. Prior to demolition an asbestos survey and/or abatement project will be performed on the building. All metal demolition debris will be transported to an appropriate off-site facility for recycling as scrap metal. 2. Excavation and removal of all reasonably accessible surface and subsurface soils containing total petroleum hydrocarbons (TPH), volatile organic compounds (VOCs) and/or MTCA 5 Metals at levels that exceed MTCA Method A Clean Up Levels for Industrial Properties. 3. All excavated soils will be temporarily stockpiled on-site. All stockpiled soils will be properly tarped as necessary. 4. All soils containing the contaminants of concern at levels exceeding applicable cleanup levels will be properly loaded and properly transported to either Waste Management’s Duwamish Reload Facility in Seattle or Republic Services facility in Seattle using dump trucks. All soils will be transported under a properly issued manifest/waste disposal authorization. 4 5. It is anticipated that 8,500 + cubic yards (11,900 + tons) of contaminates of concern contaminated soils will be excavated, removed, and transported to the designated off-site disposal facility. Currently, it is anticipated that the remedial excavation area will be extended to all of the perimeters of the subject property. 6. An appropriate number of confirmation soil samples will be obtained from the completed remedial excavation floor and sidewalls on a periodic and regular basis as per applicable guidelines. 7. All confirmation soil samples will be analyzed for the presence of gasoline range TPH using method NWTPH-Gx and VOCs using method 8260, diesel fuel and lube oil range TPH using method NWTPH-Dx/Dx Extended, and MTCA 5 Metals using EPA method 6020. 8. EPA Method 5035 sampling protocols will be followed when sampling soils to be analyzed for VOCs. NOTE: All laboratory analyses will be done on a 48-hour expedited turn around basis to facilitate prompt characterization of existing on-site conditions so that appropriate corrective and/or constructive actions can proceed immediately. 9. The excavation will be backfilled using suitable imported structural fill materials that will be mechanically compacted for stability. Compaction testing will be performed by the project’s Geotechnical Engineer. Backfill Materials Documents will be submitted to the City of Renton for review before any of the materials are transported on-site. 10. All groundwater monitoring wells located within the remedial excavation areas, that are in areas will be abandoned as per applicable regulations/guidelines. 11. Photographic documentation of all phases of the remediation project. 12. Potentially adversely impacted soils and/or waters present in the Washington Department of Transportation Wetland/Right of Way will not be excavated and/or removed as part of this remedial and/corrective actions project. 13. The results of these additional environmental investigations will determine if additional remedial and/or corrective actions are required. 14. Filing of any required permits and start cards. 15. Documentation of all on-site activities in a Department of Ecology required Remedial and Corrective Actions Report and Quarterly Groundwater Monitoring Reports. 16. A site safety plan will be developed and followed by all on-site workers. A copy of the Site Safety Plan will be on-site during all working hours. 17. Staff will have received a required minimum of 40 hours Hazmat Training. 5 18. The work area will be properly posted and secured with hazard notification signs barricades, orange hazard fencing, and/or chain link security fencing. 19. All on-site work will be performed under permits issued by the City of Renton and under the guidelines set forth in MTCA. 20. Upon the completion of the proposed remedial and corrective actions project, the site will be entered into Ecology’s Voluntary Clean Up Program for the purpose of receiving an, NFA (No Further Action) letter. F. CLOSURE Our intent is to enter into the Department of Ecology Voluntary Cleanup Program with the purpose of receiving a No Further Action (NFA) letter. This report has been prepared, in part, to address City of Renton SEPA comments. The planned cleanup will adhere to state and local requirements. This project, as planned, should not create any new problems within the downstream environment. This project will not noticeably aggravate any existing downstream problems due to either water quality or quantity. Paul W. Stemen Vice President