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On August 30 and 31, 1999, two monitoring wells (MW-7 and MW-8) were installed to 110 feet. On March 16, 2000, SJCEHD requested that the vertical and lateral extent of the documented contamination be further evaluated, and additional monitor wells be installed. JJW submitted a workplan and a workplan addendum on May 12, 2000, and July 31, ` 2000, in response to the SJCEHD directive. The workplan outlined the additional site assessment, monitor well installation, and replacement of the compromised monitor well MW-7 required by SJCEHD. SJCEHD approved the workplan on August 30, 2000. JJW completed direct push water sampling and analysis on April 6, 2001 to evaluate the site for monitor well placement. On May 2, 3, and 4, 2001, a soil boring with interval water sampling (SB2), and four additional monitoring wells (MW-9 to MW-12) were installed. MW-7 was abandoned and �• replaced by MW-7A. Quarterly groundwater monitoring continued from the eight previous and four new wells. In letters dated December 6, 2001 and August 6, 2002, SJCEHD directed that a workplan to perform remediation efforts be submitted. 3.0 EVALUATION OF POSSIBLE REMEDIAL OPTIONS �..• Possible remedial treatment options for the JC Trucking site are described below. The treatment options are then evaluated in Table I as to their individual attributes, including projected system effectiveness and overall estimated costs. Given the current lack of detection of soil contamination proposed remediation is slated to focus on groundwater ` treatment. 3.1 Groundwater Remedial Options 3.1.1 Ex-Situ Treatment Options Groundwater Extraction and TreatmenbVisposal This treatment method involves extraction of contaminated groundwater from an extraction well(s) installed at a strategic location. In addition to the removal of contaminant-laden groundwater, plume containment can be accomplished with groundwater extraction. Oftentimes, once the plume is contained, then natural �.• biodegradation can be allowed to occur without the threat of the plume spreading further, or migrating off-site. �. The extracted groundwater is either discharged directly, or is treated prior to discharge. Treatment generally consists of either liquid-phase carbon adsorption, or air stripping followed by vapor-phase destruction methodologies similar to those described for vapor extraction. The water is typically discharged to the storm drain or to the sanitary sewer (under discharge permit), or is allowed to percolate back into the soil via percolation beds. 6. �, JJW GEOSCIENCES Inc.