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Project No 014-95262 Page No 8 time of the investigation However, the 15 feet bgs samples from borings KB-4 and KB-5 were noted as moist also, as were the samples at 5 feet bgs from KB-5 and KB-6 7.2.2 Background Soil Chemistry Soil boring KB-2 was advanced in the undeveloped portion of the project site to gain an understanding of background soil conditions Analytical results suggested a moderate electroconductivity (54 to fib 1cmhos/cm), low to moderate chloride (15 to 40 mg/Kg), slightly alkaline conditions (pH = 7 7 to 8 0), and variable nitrate (8 to 64 mg/Kg), and discussed below Because of the anomalous nature of the higher nitrate concentration in soil boring KB-2 at a depth of 20 feet bgs, the analytical laboratory was asked to re-analyze the sample Two initial re-analysis results were 3 and 52 mg/kg nitrate Due to the variation noted upon re-analysis, two more portions of the sample were analyzed, both returned not- detected results The remaining sample was then homogenized and analyzed and also returned non- detected results for nitrate i Physical inspection of the sample did not reveal obvious inhomogenities in the very clay-rich soil Therefore, the initial result (64 mg/Kg nitrate) is presented in Table 2, but with the knowledge that the i above factors complicate interpretation of the data 7.2.3 Brine Spill Area Soil boring KB-1 was advanced northwest of the brine tank, just off the edge of the concrete driveway surface, at the terminus of salt staining which appeared to originate at the brine tank The obvious degradation of the concrete brine tank pedestal and build-up of salt crystals suggested spillage (possibly due to overfilling) had occurred Boring KB-1 was advanced to determine if spillage noted on the concrete surface had migrated onto nearby soil surfaces and percolated through the soil profile A review of Table 2 shows EC and chloride concentrations at a depth of 5 feet bgs to be one and two orders of magnitude greater, respectively, than background concentrations These constituents show i marked attenuation between depths of 15 to 20 feet bgs and are at or near background concentrations by 25 feet bgs 1 7.2.4 Wastewater Treatment Pond Area Soil borings KB-3 and KB-4 were advanced immediately adjacent to the treatment pond EC in samples from these borings were at background levels Chloride was elevated in boring KB-3 and at background in boring KB-4 Nitrate was detected in one of four samples fron these borings (20 feet bgs in KB-4) at a concentration of 63 mg/kg Nitrate was not detected in the sample collected five feet below the above sample Phosphate and ammonia were not detected in samples from KB-4 and were not analyzed in samples from KB-3 The pH of the 20 feet bgs sample from KB-4 (pH = 7 2) was slightly less than background A very competent dark green clay unit was noted in the 25 feet bgs sample from KB4 KRAZAN& ASSOCIATES, INC Offices Serving the Western United States 95262 Ps2