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Woodward•Clyde Consultants <br /> California Water Quality Control Board <br /> March 14, 1985 <br /> Page Two <br /> This program is anticipated to include the following elements: <br /> 1. Borings We plan to define the extent of contamination through a <br /> series of shallow borings (8 to 12) . Tentative boring locations <br /> are indicated in the appended diagram. Drill cuttings will be <br /> examined for presence of oil. PVC casing and well screen will be <br /> inserted to keep these borings open long enough to collect water <br /> surface observations. Observations will include sampling of the <br /> groundwater interface by clear bailer with examination for free- <br /> floating oil. <br /> 2. Monitoring Wells The temporary wells will either be completed as <br /> permanent monitoring/recovery wells or abandoned by removing the <br /> casing and backfilling as appropriate. A sufficient number of <br /> wells will be retained to permit adequate monitoring of the spill <br /> and remedial actions. Following well completion, well casings <br /> and fluid elevations will be surveyed to permit determination of <br /> the hydraulic gradient. If free oil is observed, gradient <br /> calculations will be corrected for thickness and specific <br /> gravity. <br /> 3. Water Quality Analysis Shallow groundwater in the immediate area <br /> is believed to be already degraded. Analysis of the material <br /> spilled (according to procedures recommended by DOHS) suggests <br /> that it is relatively innoxious. However, most petroleum <br /> products contain components which are slightly soluble in water <br /> or are susceptible to emulsification. To evaluate the extent of <br /> possible entrance of oil into and effects on the groundwater and <br /> to provide data for produced water treatment/handling, should it <br /> become necessary, water samples will be collected from wells <br /> downgradient from the plume. Such samples will be collected <br /> after development of the wells by bailing or pumping. Samples <br /> will be analyzed for presence of emulsified oil (solvent <br /> extractable hydrocarbons before and after filtration) and soluble <br /> component indicators including benzene, toluene, and xylene (gas <br /> chromatography) . <br /> 4. Data Interpretation The data collected in the preceeding effort <br /> will be evaluated to develop an understanding of the extent of <br /> contamination, its direction and rate of migration, and the <br /> degree of contamination of underlying groundwater, if any. <br />