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' 5.0 SUMMARYAND CONCLUSIONS Ij The main objective of this assessment was to conduct an environmental ' site investigation to evaluate current site conditions. h1 general, all proposed investigation work was completed. Based on the findings of the Phase II Environmental Site Assessment at the Lesco facility in Stockton, California,ERM has reached the following conclusions for soil and groundwater. 5.1 SOIL ' • Unidentified TPH compounds, outside of the typical diesel standard, were the only constituents detected in shallow soil samples collected in ' the three shallow borings. TPH in shallow soil at the reported detections poses an insignificant threat to site environmental quality. Organochlorine pesticides, organophosphorous compounds, and ' chlorinated herbicides were not detected above laboratory reporting limits in soil samples collected from SB-4 through SB-7. • Chloride,nitrate, sulfate, and ammonia as nitrogen are present in '] chemicals used in fertilizer manufacturing operations. Elevated concentrations of these anions in the thousands of mg/kg are commonly found as a result of agricultural practices in the Great Valley. C111oride, nitrate, sulfate, and ammonia as nitrogen were observed in soil samples collected from SB-4 through SB07. JRegulatory limits for these elements have not been established. • Soil pH was above the suggested level in soil borings SB-6 and SB-7 ' and below the suggested level in soil boring SB-4. ' 5.2 RECONNAISSANCE GROUNDWATER In general, groundwater flows in a southerly direction at a gradient ' between 0.0115 and 0.0156 feet per foot. Metals such as arsenic,beryllium, cadmium,chromium, copper, nickel, ' lead,selenium,zinc, and mercury are present in groundwater above the respective PMCL/SMCL and Region IX tap water PRG. It is noted ' I.I(ni 13 LF5C0/W24M1-3/3/2W5