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a <br /> Report of Results <br /> Investigation of Agricultural Chemicals in Soil <br /> PttreGra/Brea Facility <br /> 1905 North Broadway Ave.,Stockton.CA <br /> fi <br /> Sierra-Pacific Project No.94-055.09 <br /> Broadway Avenue on November 21, 1995. Monitoring well MW-8 was installed at 1836 North Sutro <br /> Avenue on November 22, 1995. Monitoring well MW-7 was completed on March 25, 1996, also at <br /> 1836 North Sutro Avenue. MW-9 was installed on October 9, 1996 on Lewis Street. Additional project <br /> information is available in earlier reports, the titles of which are listed in Section 8.0 of this report. <br /> The monitoring well array has been sampled on a quarterly basis since 1.993. One of these wells,MW4, <br /> was abandoned in late 1996 by Sierra-Pacific to facilitate the placement of a liner and cap above the <br /> it <br /> south pond. 1,2-DCP, 1,2,3-TCP,and other chemical compounds have-been found at low levels in wells <br /> A <br /> in proximity to or down-gradient from the two former evaporation ponds. Nitrates have also been found <br /> , <br /> in these wells and in the up gradient wells. <br /> In addition to the installation of monitoring wells as described above, in 1995, four deeper soil borings <br /> i' <br /> were advanced in the north and south pond areas by Sierra-Pacific- Various chemicals were detected <br /> in soil samples collected. Shallow soil samples were also collected by Western Farm Service in front <br /> t <br /> (north of) the oId PureGro warehouse, now called the WFS maintenance shop. Other shallow soil <br /> samples were collected west of the new tank farm. Nitrogen compounds were detected in most of these <br /> samples at concentrations up to 8,400 mg/kg (TKN), 3,600 mg/kg (N-NO3), and 1,200 mg/kg(N-NH4). <br /> Ground-water sampling is currently conducted on the nine monitoring wells semi-annually,and ground- <br /> water level measurements are performed on a quarterly basis. ''Several contaminants of concern have <br /> been identified by RWQCB based upon the results of previous investigations. These include: nitrogen <br /> as nitrate, total Kjeldahl nitrogen, ammonia nitrogen, 1,2,3-trtrichloropropane, 1,2-dichloropropane, <br /> bromodichloromethane, chloroform, dibromochloromethane, ',`dibromochloropropane, Dinoseb, and <br /> ethylene dibromide. <br /> i <br /> L <br /> 4. <br /> { <br /> Sierra-Pacific Groundwater Consultants, Inc. 6 <br />