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U Water quality monitoring and sampling for the Forward Landfill located within the Central Valley RWQCB Region was conducted by Del -Tech geotechnical support services (Del -Tech). Sampling and analyses were performed in general accordance with WDR Order No. R5-2003- 0049 issued specifically for the Forward Landfill and the sampling and analysis plan prepared by Kleinfelder (1994) for the Forward Unit. The information contained in this sampling and analysis plan supplements sections related to sampling and analysis in the Kleinfelder Field Activities Protocol (1994; attached). A brief summary of the protocols for sample collection is presented below. Chemical analyses were performed by BC Laboratories, a state -certified laboratory. Groundwater and vadose zone samples were analyzed for the list of parameters summarized in Table 1B, which also present the laboratory analytical methods used during the sampling event. Copies of the certificates of analyses and Chain -of -Custody records for the samples collected this quarter are included in Appendix C. Groundwater Sampling The sampling protocols listed below were generally followed during groundwater sampling operations: • Upon arrival at the wellhead, each monitoring point was inspected for evidence of tampering and/or vandalism, and the well identification (I.D.) was recorded. ® Most of the groundwater monitoring wells at the Forward Unit are equipped with dedicated pumps. Well construction details including: well depth, well diameter, screen slot size, filter pack, top of casing elevation, and coordinate location are summarized in Table 2B. The water level was measured directly using a weighted water -level indicator (sounder) to an accuracy of 0.01 foot. Prior to measuring the water level, the sounder was decontaminated using an Alconox® soap solution, followed by two rinses with deionized water. The wells were then sounded and the initial water level and the total depth of the well (if obtainable) were recorded on a Well Data Sheet. Groundwater Sampling Using Traditional Well Sampling Methods For the Forward Unit wells and wells with non -dedicated sampling equipment, up to three casing volumes (under optimal conditions) of water were purged prior to sampling. Based on the measured depth to water, the total depth of the well, and the known casing diameter, a well casing volume was calculated using the following equation: DAFomsrdSAplen.doc