ARCHIVED REPORTS_PHASE II PRELIMINARY SITE ASSESSMENT- SOIL SAMPLING AND TESTING

Home Browse Search

Weston Ranch Towne Center,Stockton, CA D47223.01Page 5 August 21,2006 ' Pesticides were detected in two of the thirteen soil samples (S-7 and S-9). On June 28, 2006, soil samples were also taken at depths of 2 feet from sample locations S-7 and S-9 and analyzed for ' pesticides. The analytical results of the soil samples at the shallow and deeper depths (2 feet) revealed low concentrations of pesticides. DDE was detected in S-7 and S-9 in the surface sample at 0.059 and 0.032 mg/kg, respectively, and at the 2 foot bsg at 0.53 and 0.06 mg/kg,respectively. The soil sample from S-7 at 2 feet bsg detected DDT at 0.17 mg/kg, alpha-Chlordane and gamma- Chlordane were detected in S-7 from the near surface at 0.095 and 0.1 mg/kg, respectively. The ' analytical results of soils for metals revealed non-detectable concentrations to low concentrations. The concentrations of pesticides and metals were below regulatory levels referenced in Title 22 for ' Total Threshold Limit Concentrations and the EPA Region 9 Residential PRGs. The locations of the soil samples are shown on the attached Drawing 4. The laboratory results are ' summarized in Table 4. The laboratory analytical reports are attached to this report. CONCLUSIONS ' Based on the results of the field investigation and laboratory testing,the following conclusions are presented. • The study did not reveal the presence of a UST. In addition,the analytical tests conducted on soil samples taken from the location of the suspected former UST excavation did not ' reveal detectable concentrations of constituents of concern.. • The analytical results of the soil samples taken from the area formerly occupied by the barn and shed revealed low concentrations of constituents of concern, i.e., TRPH, metals and pesticides. The concentrations appeared to be below typical regulatory action levels. ' The analytical results of the composite soil sample (BP-lBP-2) taken from the area of the suspected burn pit revealed non-detectable concentrations for TRPH and pesticides with no dilution. The analytical results of the soil samples tested for metals revealed low concentrations which appear consistent with the concentrations of metals detected in other samples from this investigation and are below typical regulatory levels and are probably ' background for the area. • The analytical results of the soil samples taken in the agricultural fields revealed low levels of pesticides in the near surface soils at two of the thirteen sample locations. The detected concentrations for pesticides were below residential PRGs and TTLC levels.