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Based on the results of the groundwater monitoring and sampling activities, Ramage Environmental recommends the following environmental corrective actions 1 Given that significant concentrations of gasoline hydrocarbons exist in soil and groundwater beneath the site and that a vapor extraction well network has previously been installed and pilot tested with favorable results, active remediation by vapor extraction may be warranted and would likely be effective and cost efficient to implement To substantiate this remedial action, a Corrective Action Plan (CAP) and design of the selected remedial alternative should be prepared in accordance with California UST Regulations (Article 11, Chapter 16) The approved final CAP and design should be used as a bid document to obtain at least three bids for the construction and operation of the selected remedial alternative so that approval for the work can be secured from the UST Cleanup Fund 2 Since the screen intervals in the five original monitoring wells no longer coincide with the rise in 1 the groundwater table, the groundwater monitoring and sampling data taken from these wells are suspect and unreliable To further delineate the extent of impacted groundwater and re- establish groundwater monitoring capability at the site, two additional groundwater monitoring wells should be installed at the site The locations of these proposed wells are shown on Figures 2 and 3 3 Groundwater monitoring and sampling of the existing wells should continue in 1998 Groundwater table conditions should be monitored on a quarterly basis by sampling VW-1, VW- 2 and the proposed monitoring wells Groundwater from these wells should be analyzed for TPH-as-gasoline, BTEX and MTBE by Modified EPA Method 8015/8020 The five original groundwater monitoring wells should be sampled on an annual basis, during the fourth quarter All groundwater samples collected during the fourth quarter should also be analyzed for oxygenate and volatile organic compounds by EPA Method 8260 4 Based on the composite sample results, drummed wastewater from drums A, B and C can be discharged to the land at the site Given that low concentrations of MTBE were detected in drums D, E and F and the three drums from MW-2, this wastewater should be filtered with granular activated carbon and re-sampled prior to discharge Since sanitary sewer service is not available at the site, the filtered wastewater should also be discharged to the land 6