2.1.1 Narrative

Installation of an initial clay cover over the exposed waste cell at the northeast corner (near the scale house) was initiated on September 12 and was completed by September 17. Installation of a 12-inch clay layer over thinly covered trash surfaces in the center of the landfill top were initiated on September 17 and will be complete in approximately 4 days. Staking of the landfill top has begun in preparation for the final 12-inch clay layer which will cover an area of approximately 3.7 acres, beginning west of the former burn area and north of the old closed disposal area.

Due to excessive stormwater surge which destroyed a check dam ahead of the detention pond, the OSCs approved construction of an intercept dam at the entrance to the detention pond in order to reduce stormwater and sediment surge to the pond. The dam was constructed of clay from the West Ridge Borrow Zone and extends three feet below ground surface in order to prevent undercutting. It is 20-feet wide at its base and 10-feet wide at its top and rises approximately 5 feet. Four 12-inch ADS pipes protrude through the dam at differing elevations and a riprap-ed spillway is built over the west side. If they can be obtained, HDPE headwalls will be installed. The dam was completed on September 18 and effectively creates an upstream detention area at the southwest corner of the Site, which is flat and consists of a sandy soil base. In order to reduce stormwater volumes and velocities from other locations at the side, a second smaller dam was also constructed within the drainage channel west of the asbestos cell. 

Repairs were made to rill erosion on the toe of the landfill face and the asbestos cell on September 17 and 18. Initial lime was applied to the asbestos cell and surrounding area on September 18 and will be applied at a rate of approximately 4000 pounds/acre. Seeding, fertilization, and straw installation on the asbestos cell began in September 18. Straw will be blown on flat surfaces and straw matting will be installed on side slopes. 

Vegetation efforts appear successful and seed is sprouting in all areas. The initial batch of rye and fescue on the landfill face has exceeded 6-inches and is abundant but this is in a location where a thin layer of topsoil was installed. Sprouting in clay areas where no topsoil was installed is initially successful with clover with rye and fescue sprouting later and with less abundance. Seed, lime, and fertilization rates will be adjusted as needed.

START contractors continued daily collection of subsurface air well measurements from September 14 to 18. Well air readings appear to be consistent with previous weeks. An examination of the laboratory results for air samples taken from the wells suggests that low oxygen results reported by the lab may actually be argon, which the methodology states: "coelutes" with oxygen and is mixed with the oxygen measurement. Since atmospheric levels contain nearly 1% argon, this may suggest the possibility of air infiltration to the subsurface.

2.1.2 Response Actions to Date

• May 25-29: ERRS mobilization, site preparation  (access roads, entrance, trailer, work zones) 
• June 1-2: Grading and wetting burned area
• June 3: First record of no morning smoke observed
• June 3-5: Continue grading and wetting burned area. Moved cover soils from borrow area to burned area
• June 5-26: Continue grading and covering operations.
• June 16: Exhausted stockpile of cover soil at top center of Site
• June 26 Initial cover soil installation completed.
• June 29 Initial six inches of clay cap begun. Completed on July 3rd.
• July 2nd Three additional gas monitoring wells installed to monitor landfill carbon monoxide and temperatures near former burn area.
• July 13-17: Began removal of trees and topsoil from West Ridge Borrow Zone
• July 14: Exhausted Old Yard Stockpile at the south side of the Site
• July 14-17: Begin installation of second 6" clay layer on burn area
• July 20-22: Complete second 6" clay lift on burn area
• July 22: Conducted compaction testing by PSI Inc - 30 of 34 grids passed
• July 23: Begin installation of third clay layer on landfill face area
• July 28: Complete excavation of 3 vertical feet of sediment from detention pond
• July 29: Consultation with Clemson University Extension Office for Soil quality and vegetation
• July 27-31: Continue installation of third clay layer on landfilled face area reaching 90% completion
• Aug 6: Conducted round 2 of compaction testing, 27 of 28 grids passed.
• Aug 14: Completed fourth and final clay layer on the face area
• Aug 12: Begin removal of Knoll Borrow Zone
• Aug 12: Begin initial cover installation on Asbestos Cell
• Aug 17  Initial cover of Asbestos Cell completed
• Aug 29  Final cover of Asbestos Cell completed
• Aug 25  Begin installation of topsoil on former burn area
• Aug 29  Begin installation of vegetative cover on former burn area
• Aug 29  Complete stormwater protection measures on detention pond. 
• Aug 31  Begin grading northeast debris cell
• Sep 17  Complete initial 12-inch soil layer on northeast debris cell
• Sep 18  Complete construction of dams above detention pond and in west stormwater channel

• Isolation of burning material by removal and relocation of available fuel path and installation of earthen cover; (ONGOING)
• Isolation of designated asbestos disposal cell through the installation of earthen cover; (COMPLETE)
• Re-grading waste materials and native soils for purpose of cover installation; (ONGOING)
• Installation of temporary measures to prevent off-site migration of dust or contaminants as removal operations are conducted; and, (ONGOING)
• Continue sampling and monitoring, as needed, for site safety purposes and to further delineate or identify contaminants. (ONGOING)

2.2.1.2 Next Steps

1. Complete initial and final clay cover on landfill top, then vegetate
2. Complete topsoil installation on landfill face, then vegetate and install flow interruption devices
3. Vegetate asbestos cell
4. Complete excavation of sediment pond, replace riser stone, and vegetate berm walls
5. Vegetate all remaining exposed areas
6. Water until vegetation established

6.2 Reporting Schedule

New POLREPS will be issued weekly on Fridays for the duration of on-site activities.

Daily photos of site conditions and progress are being posted to the "Images" section of epaosc.org/bennettlandfill. These photos are collected from the same general locations each day.