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ranged from 6.70 in MW-1 to 7.06 in MW-3. Groundwater temperature ranged from 18.9 degrees Celsius in MW-3 to 22.3 degrees Celsius in MW-2. Conductivity ranged from ' 1090 micro ohms in MW-2 to 2530 micro ohms in MW-3. The wells were allowed to recharge a minimum of 80% before sampling. Samples were collected from each monitoring well along with a blind duplicate. Water samples were collected by lowering a ' disposable bailer below the static water level, and raising the bailer slowly in order to minimize agitation of the water sample in the bailer. Water was discharged from the bailer through a bottom discharge valve. Discharge to the ' sample container was at a rate slow enough to minimize bubbling or significant agitation of the liquid. The sample container was filled to the top (from the bottom up) and overfilled leaving no headspace. ' The samples were collected in laboratory-approved glass vials and bottles. Following collection of the samples,they were placed in an ice chest cooled with ice to a temperature of approximately 40°to 50°F. Samples were then delivered to the laboratory within 24 hours of collection. Sample handling, transport and delivery to the laboratory were documented using chain-of-custody ' procedures, including the use of chain-of-custody forms. Quality Assurance/Quality Control ' To increase the confidence levels in the data obtained and minimize the likelihood that judgments were made from potentially erroneous data, a quality assurance/quality control (QA/QC)program was implemented. The program includes formal procedures for drilling, sampling, decontamination, instrument calibration, documentation of field activities and calculations, and peer review. ' Routine QC procedures were performed by the laboratory,and included daily calibration of instruments, percent surrogate recoveries, and analysis of matrix spikes and matrix spike duplicates. The laboratory reported the results to be within acceptable percent error with no results exceeding the laboratory-established control limits. Decontamination ' The hollow-stem augers were decontaminated prior to the advancing of each boring. The sampler was decontaminated between sampling intervals, using a bristle brush, with a trisodium phosphate (TSP) solution; this was followed by two tapwater rinses. The sampler was dried by air prior to use. ' Waste Disposal ' The soil cuttings and purge water produced during the site investigation were placed in DOT drums and stored on site pending analytical result. The soil cuttings and purge water will be transported and recycled/disposed of by a licensed hauler in accordance will ' appropriate regulations. FIELD OBSERVATIONS Soils beneath the site consisted primarily of silty clays, silty sand and silts. Groundwater was encountered at approximately 55 feet bgs during drilling activities. Elevated PID 8 197046a - Stockton