Past Work on Site

The Village Council and School District Tank Farm- This site consists of seven vertical above ground storage tanks (ASTs) which are reportedly still on site. During a site inspection in 2002, a petroleum odor and a slow leak on the main supply line from the ASTs was noted. Seven soil samples and one ground water sample collected from outside the lined, bermed area of the tank farm contained DRO up to 4,340 mg/kg at 2.5 feet bgs and 2.03 mg/L, respectively. Frozen soil was encountered at 4.5 feet to 7 feet bgs and groundwater was encountered at 6 ft. bgs. An estimated 130 cubic yards of contaminated soil remains onsite. • Generator Building- Drums and soil staining were observed at this site during a site inspection in 2002. A soil sample collected from the visually stained area at 1 foot bgs contained DRO up to 14,800 mg/kg and GRO up to 1,850 mg/kg. A soil sample collected at 8.5 feet bgs contained DRO up to 7,740 mg/kg and naphthalene up to 61.7 mg/kg. A groundwater sample collected from a well point installed south of the generator building contained DRO up to 7.61 mg/L, GRO up to 15.1 mg/L, and benzene up to 0.685 mg/L. An estimated 35 cubic yards of contaminated soil remain on site. • Northern Teacher’s Housing- Soil staining and petroleum odor were observed at this site during a site inspection in 2002. Seven soil samples collected contained DRO up to 19,100 mg/kg, GRO up to 1,010 mg/kg, ethylbenzene up to 15.4 mg/kg, and xylenes up to 100.9 mg/kg. at 1 foot bgs and DRO up to 2, 460 mg/kg at 3 feet bgs. An estimated 38 cubic yards of contaminated soil remain on site. • Southern Teacher’s Housing- Soil staining was observed at this site during a site inspection in 2002. One soil sample collected from a stain beneath the HOT at 1 foot bgs contained DRO up to 14,800 mg/kg and xylenes up to 90.7 mg/kg. An estimated 25 cubic yards of contaminated soil remain on site. • Water Treatment Building- Soil staining was observed, reportedly from a pipeline leak, during the 2002 site inspection. A soil sample collected at a depth of 0.5 feet bgs contained DRO up to 19,000 mg/kg, GRO up to 979 mg/kg, ethylbenzene up to 19.4 mg/kg, and xylenes up to 143.3 mg/kg. An estimated 25 cubic yards of contaminated soil • On May 6, 2009, 75 gallons of diesel fuel leaked out of a fuel pipe located 40 feet west of the Chalkyitsik School playground due to operator error. On May 14, 2009, PERP arrived on scene as part of the Yukon River flood response team. Guided by visual and olfactory senses only, a 20 foot by 60 foot area of contaminated soil was excavated from underneath the pipeline. The approximately 20 cubic yards of contaminated soil was then put on a 20 mil liner biocell and fertilized south of the school.