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Date September 18,2002 <br /> Quarter. 3d Quarter,2002 <br /> APPENDIX B <br /> SAMPLING AND ANALYSIS PROCEDURES <br /> Sampling Procedures <br /> Sampling equipment is thoroughly cleaned prior to each sample The sampling procedure for each well includes <br /> measuring the water level and checking for the presence of separate-phase hydrocarbons (SPH), using either an <br /> electronic indicator and a clear Teflon bailer or an oil-water interface probe If the measured water level in the well <br /> is below the top of casing elevation,the well may be sampled without purging For non-purge wells,one set of water <br /> quality parameters are collected and the well is sampled with a disposable bailer Wells not containing SPH that do <br /> not qualify as non-purge wells are purged of approximately three casing volumes of water (or to dryness) using a <br /> submersible pump,centrifugal pump,gas displacement pump,or bailer The optimal purging rate is approximately 1 <br /> gallon per minute The equipment and purging methods used for the current sampling event are noted on the <br /> attached field data sheets During purging, temperature, pH, electrical conductivity, and dissolved oxygen are <br /> monitored in order to document that these parameters are stable prior to collecting samples After purging, water <br /> levels are allowed to partially recover Groundwater samples (both purge and no-purge) are collected using a clean <br /> disposable Teflon® bailer, placed into appropriate EPA-approved containers, labeled, logged onto chain-of-custody <br /> documents,and transported on ice to a California state-certified laboratory <br /> Decontamination Procedures <br /> Prior to sampling each well,reels and pumps will be decontaminated with a steam cleaner Sensitive equipment such <br /> . as the water level sounder are sprayed with a non-phosphate soap and delonized water solution and rinsed with <br /> de►omzed water All water used for equipment decontamination is collected and contained in a truck-mounted water <br /> tank <br /> Laboratory Procedures <br /> The groundwater samples are analyzed for the presence of TPHG, benzene, toluene, ethylbenzene, xylenes (total), <br /> and MTBE using EPA Methods 8015 (modified) and 8021, and fuel oxygenates using EPA Method 8260B The <br /> methods of analysis for the groundwater samples are documented in the certified laboratory analytical report The <br /> certified laboratory analytical report, chain-of-custody documentation, and field data sheets are presented as <br /> appendices <br /> Purge and Rinsate Water Disposal <br /> Water generated during well sampling and equipment cleaning is pumped into a truck-mounted water tank The <br /> water is transported to Atlantic Richfield Company's holding facility in West Sacramento, California, for temporary <br /> storage Water 1s then transported by Dillard Environmental to the Altamont Landfill and Resource Recovery <br /> Facility in Altamont,California for disposal <br /> • <br /> K V5$p ARCOV 11931Quwte,jyL3 Q'IR_021GWMR&c Page B-1 <br />