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1 ' borings BH Nos C-4/C-6 and C-5/C-7 indicated a lighter extractable C10-C-28 fraction The bonngs were grouted closed after collecting samples and could not be retested Chromatograms from laboratory analysis were submitted in the June 2002 interim report along with complete laboratory reports The most recent March 2005 sampling laboratory findings are included herewith Reference ATTACHMENT 4, 1 EXTRACTS FROM ANALYTICAL LABORATORY FINDINGS- December 2005 During the December 2005 sampling, the "diesel" fraction was detected at levels ' between <0 05 and 0 79 mg/Itr Level in MW No 1, the original MW installed in December 2000, had continued to increase from 0 47 mg/Itr recorded in March 2004 to 0 86 mg/Itr in December 2004 but has decreased to 0 82 mg/ltr Levels in MW No ' 2 decreased from 0 33 mg/ltr recorded in December 2004 but rebounded upwards to 0 51 mg/ltr Results are listed separately in the last page of the ATTACHMENT 2, "SITE CHARACTERIZATION -SUMMARY OF LAB RESULTS Soil Quality Shallow trenching in November 2004 revealed that oil contamination from petroleum hydrocarbons was found in several areas of varying depth and concentrations Levels of BTEX were detected in previous exploration in the 10 to 15 FT bgs zone along the east fence at less than 100 ug/kg and at a deeper 25 FT bgs at levels of 688 ug/kg of Xylene During earlier testing in March 1999, Galardo identified considerable BTEX in BH No B-1 in the vicinity of later installed MW No 1 and in BH No 2 near the east fence Diesel contaminated soil was found near MW No 4 particularly in the 25 to 30 FT bgs zone and MW No 2 near the east fence in June 2002 Earlier borings by Gallardo and Barber found diesel at the 13,000 to 15,000 mg/kg levels in the same area Earlier borings by Gallardo and Barber found concentrations of upwards to 30,000 mg/kg in the vicinity of MW No 1 and BH No B-1 at similar depths ' Review of previous geological findings and field findings in June supported the contention that there was dispersion of diesel in the 25 FT to 35 FT bgs zone atop an aquatard, possibly with earlier perched waters Perched waters were not found at this Idepth by Stellar or Barber in December 2000 or the later June 2002 exploration Near the east fence during construction of MW No 2 in June 2002, minor seepage of product (diesel like) and shallow water were apparent in the upper 0 to 10 FT bgs stratum ' Recent Soil Contamination Findings During Shallow Excavations Shallow sod was sampled November 22, 2004 between the existing AST (MW No 1 ' and the eastern property line including the area surrounding MW No 2 Results are • attached as a separate summary Diesel and motor oil fractions were found ranging between 6 mg/kg to as high as 14,000 mg/kg Trenching, by WOS, in the area ' between MW No 2 (east fence line and the concrete block wall secondary 4