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presence of hydrocarbon vapors with a photo-ionization detector before being examined and described on the boring log. The boring east of the dispenser island will be continuously sampled with a 5-foot-long core barrel and will be described in detail. Selected samples may be preserved in brass tubes for laboratory analysis of hydrocarbons and/or lithologic properties. A grab sample of the groundwater will be collected from the one boring that is not completed as a well. The new wells will be purged of at least 5 well volumes prior to sampling, and will be allowed to stabilize. Temperature, pH, dissolved oxygen, and conductivity will be measured at intervals during purging to assure that the wells have stabilized. Samples will be collected from each well, including KF-1, -2, and -3, in disposable bailers, poured into sterilized 40-m1 vials, and preserved in a cooled ice chest for shipment. The purged water will be transported and disposed of at Americlean's disposal facility outside of Reno,Nevada. 3.3 Grouting and Well Completion The boring will be grouted to the surface with a neat cement slurry. The wells will be completed as 2-inch-diameter wells (Figure 4). We estimate that the screened interval will be from 30 to 10 feet. 3.4 Well Surveying The elevation of the new wells will be surveyed with respect to the existing wells. A notch will be cut into the top of the well casing and used as the reference point for surveying and measurement of the depth to groundwater prior to purging. 3.5 Laboratory Analysis Based on the results of soil samples from the previous wells, signficant soil contamination is not anticipated. Hence, it is likely that only one or two soil samples from each boring will be analyzed for hydrocarbons unless field screening dictates otherwise. The samples will be analyzed for the following constituents: Total Petroelum Hydrocarbons as gasoline (EPA 8015) BTEX and MTBE(EPA 8020) Seven gasoline oxygenates(EPA 8260) Water samples will be analyzed for the same analytes using EPA methods 602, 8020,and 8260. Selected soil samples will also be analyzed for permfability, total organic carbon, and bulk density. This information will be useful in calculating the groundwater flow rate, evaluating the potential for natural degradation of the contaminants, deciding whether active remediation is warranted, and assessing the risk of the contamination to public health.