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0 <br /> The results of the 5-year COC sampling conducted during the second quarter 2008 monitoring period <br /> indicates that excluding the metals,the following CDCs were detected in groundwater and surface <br /> water samples at the Forward Landfill Unit: 2,4,5-T was detected above the practical quantitation <br /> limit(PQL) in the sample collected from well MW-2A; trace level concentrations of bis(2- <br /> ethylhexyl)phthalate were measured in the samples collected from wells MW-IA, MW-16, MW-17, <br /> MW-21, and MW-24; sulfide was detected above the PQL in the sample collected from well MW- <br /> 24; cyanide was detected above the PQL in the sample collected from surface water station FSW-1; <br /> and a trace level concentration of cyanide was detected in the sample collected from surface water <br /> station FSW-2. Confirmation samples will be collected in August 2008 for each COC measured <br /> above a PQL including 2,4,5-T at well MW-2A, sulfide in well MW-24, and cyanide at surface water <br /> station FSW-1. In addition, maximum concentration limit(MCL)exceedances for the metals <br /> manganese and nickel were identified in several groundwater monitoring wells. However, <br /> considering the distribution of these detections and the relative immobility of metals in the neutral <br /> pH environments that exists at the Forward Unit,the metals results do not appear to reflect a landfill <br /> release to groundwater. <br /> Groundwater quality conditions beneath the Austin Unit during the second quarter 2008 monitoring <br /> period are generally similar to historical results. CLs were exceeded in DMP wells AMW-2,AMW- <br /> 6,AMW-7,AMW-13, and AMW-14. However,none of the CL exceedances exhibited statistically <br /> significant increasing trends. In the corrective action program (CAP)wells,trend analyses are <br /> performed instead of comparison to CLs. During the current monitoring period, one or more <br /> statistically significant increasing trends were noted for VOC constituents in CAP wells AMW-1, <br /> AMW-10, and AMW-19, while decreasing VOC trends were noted in CAP wells AMW-1,AMW-4, <br /> AMW-10, and AMW-11. The increasing cis-l,2-dichloroethene trends in wells AMW-1 and AMW- <br /> 10 suggest that active reductive dechlorination is occurring in the vicinity of this well. <br /> The results of COC sampling during the second quarter 2008 monitoring period indicates that <br /> excluding metals which may be naturally occurring, only a few COCs were detected in groundwater <br /> samples and no organic COCl were detected in the surface water samples at the Austin Landfill Unit. <br /> Trace level concentrations of bis(2-ethylhexyl)phthalate were measured in the samples collected <br /> from wells AMW-6, AMW-7, AMW-5R, and AMW-1913R. However,this compound is a common <br /> field/laboratory contaminant associated with plastics. Dicamba was detected above the PQL in the <br /> sample collected from AMW-4, and sulfide was detected above the PQL in the sample collected <br /> from well AMW-10. Confirmation samples will be collected in August 2008 to verify the presence <br /> of dicamba at well AMW-4 and sulfide in well AMW-10. Of note, no organic COCs exceeded <br /> Federal or State MCLS at the Austin Landfill Unit. <br /> If you have any questions regarding this report,please call me at(858)451-1136. <br /> Sincerely, <br /> St T" <br /> Iliam B. Lope , EG, CI-Ig <br /> Project Geologis <br /> C:\2008-OO10\ForwardLtr_2Q08.doc <br /> - - <br /> GeoLogic Associates <br />