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GeosyntecO <br /> consultants <br /> ' • Former South Pond Area: <br /> o Two borings with samples collected from 0 - 3 and 3 - 6 ft bgs in <br /> September 1994; and <br /> ' o Two borings with samples collected from 5.5 - 6, 10.5 - 11, and 15.5 - <br /> 16 ft bgs in January 1995. <br /> Following this pond investigation, the ponds were both capped and closed under <br /> RWQCB supervision. <br /> ' The soil samples collected from both ponds in 1994 and 1995 were analyzed for volatile <br /> ' organic compounds (VOCs), organochlorine pesticides, organophosphorus pesticides, <br /> chlorinated herbicides, organonitrogen pesticides, fumigants, TKN, and nitrate. Soil <br /> samples from the former North Pond Area were also analyzed for carbamate and urea <br /> ' pesticides. Results of the 1994 and 1995 soil sampling are provided in Appendix A <br /> (Sierra-Pacific, 1995) and are summarized as follows: <br /> ' • Former North Pond Area: <br /> 0 1,2-DCP, chloroform, and nitrate were detected in all soil samples. <br /> ' Concentrations of these COCs indicated an overall decrease with respect <br /> to depth. The only exception was the deepest sample interval (70.5 to 71 <br /> ft bgs), which was collected at the water table, and may have had an <br /> inaccurate measurement due to the sample being partially or fully <br /> saturated. <br /> o Shallow soil samples (<6 ft bgs) also had detections of propoxur and <br /> chlorphopham (carbamates); and a number of chlorobenzene; 1,2- <br /> dichlorobenzene (1,2-DCB); and a number of organochlorine; and <br /> organophosphorous compounds. <br /> ' • Former South Pond Area: <br /> o 1,2-DCP was only detected in one sample, which was collected at a depth <br /> ' of 10.5 ft bgs. <br /> o Nitrate was detected in all samples with the higher concentrations <br /> generally detected in shallower samples. <br /> 1 <br /> Work Plan-Stockton Pond Inv_01-07-08 4 01.07.08 <br />