ARCHIVED REPORTS_XR0012702 - Laserfiche WebLink

Home Browse Search

275 Grantline Rd. page 4 of 7 dispensing lines. Sample SS-1.1 was collected at a depth of 8 to 9 feet below grade and northeast of the tank excavation pit to serve as a background sample. Sample SS--12 was collected from an area east of the product lines, at a depth of 3 to 4 feet below grade, and also serves as a background sample. Two samples o` the pump island area were also taken, PI-1 and PT-2, at depths of 4 feet and 2 feet respectively. A large cobble was encountered at a depth of 2.5 feet in the location of the PI-1 sample and a sample was collected at a depth of 4 feet below grade. The product line and pump island excavations were backfilled and resurfaced on July 26, 1990 after analytical results were received. LABORATORY ANALYTICAL, RESULTS-SOILS Soil same es # 1 through # 6, 9-A and # 11 were analyzed for Total Oil and Grease (Standard Method 503 b & E) . Samples SS-7 through SS-12 were analyzed for TPH (as gasoline)/BTEX (EPA Method 5030/8015 and 8020) ; SS-11 was also analyzed for Oil and Grease. The analytical results indicate concentrations of Oil and Grease, TPH (as gasoline)/BTEX to be below test method detection limits of 50 parts per million (ppm) , 2 .5 ppm and 5 parts per billion (ppb) respectively in 13 of the 14 samples collected. Only sample SS-10, near the product lines, revealed a concentration of TPH (as . gasoline) of 2 .6 ppm, 0.1 :ppm above the detection'.level for TPH' (as gasoline) . A BTEX :Concentration of 9.8 ppbwas.. indicated also; this concentration of BTEX ;was contributed by Total- Xylenes, no concentration of Benzene, Toluene or Ethylbenzene was detected. Total Xylenes are often a . common component of residual gasoline contamination found .in shallow or surface soils near pump islands of product lines. ThPoseCanthreat to the f, TPH (as a gasoline) _and BTEX do. nota ear to 9 red 8 feet deeper on .the site. LABORATORY ANALYTICAL RESULTS-PIT WATER Analytical results of the grab sample of the pit water indicate concentrations of TPH(as gasoline) EPA Method 5030/8015) of 1.8 ppm, BTEX (EPA Method 602) concentrations of 7 .5 ppb, Oil and _Greas--e _(Standard_Method-.-503 -A & -E) concentrations of 2. 8 ppm, and a .42-Dich'loroethane concentrat;.onof 4:.2 ppb. These .levels of contamination are above state and local corrective action levels for contaminated groundwater and will have to be remediated (cleaned up) to acceptable standards. The attached proposal addresses this remedial action plan. SUMMARY OF FINDINGS 4tj 1. In general, a. brown and grayish-brown, dry, stiff clay underlies the site to a depth of approxi pPzoximately 2 feet.