SITE INFORMATION AND CORRESPONDENCE

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�!`' •'6.'.• ''�, ham• _ v r Ms. Meays June 9, 1992 Page 2 activities in December 1991. This well will be a two-inch diameter wellC to ssimilarinstall t n design and depth to P-1. A workplan will be prepared on replacement well which will provide all the necessary construction details, soil and groundwater sampling protocols and health and safety concerns. Additionally, a well construction permit will be filed with the SJCPHS. RECOMMENDATIONS FOR DISPOSAL/REMEDIATION OF STOCKPILED SOILS As a result of the January 1990 removal of two underground storage tanks and the subsequent December 1991`remedial excavation, approx �natel i 1200 Dose cubic yards (LCY) are currently stockpiled on-site. Stockpile soils were separated according to moisture content and general screening procedures. The stockpile soils will be characterized in place through a program of analytical testing for petroleum hydrocarbons as diesel [EPA Method uene5 eth8015)] and benzene andnxy xylene (EPA Method atic volatile organic compounds to include benzene, Y 8020). The stockpile soils whose hydrocarbon and organic concentration levels permit Class III disposal will be transported off-site and disposed at the most appropriate and cost effective solid waste landfill available. Stockpile soils not meeting the acceptance criteria for Class III disposal will be remediated on-site to the point where,Class III disposal is possible. These soils will be subjected to microbiological treatment for a period long enough to reduce hydrocarbon and organic concentrations to meet Class III disposal criteria. The remediated soils will be transported off-site for subsequent disposal at an appropriate and cost effective solid waste landfill. The treatment/disposal process is anticipated to take from three to six months. A detailed treatment/disposal plan providing the stockpile soil sample locations, analytical testing, biotreatment design and anticipated resuits, narnes autd-locaticr's of the landfill(s) most likely to be used, project schedule, and health and safety plan will be provided to the SJCPHS for review and approval. MITIGATION OF RESIDUAL SOIL CONTAMINATION The quantity of residual soil estimated to be above nondetectable limits relative to total petroleum hydrocarbon as diesel is estimated to be between 5 to 15 LCY. This quantity is based on observations made during the December 1991 remedial activities and the fact that soil hydrocarbon/organic levels are below detection levels at MW-1, less than ten feet north of the observed residual soil contamination. The 13RUNSING ASSOCIATES, INC.