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Ms. Anne C. Conner September 22, 2009 2 PG&E also submitted a brief Project Summary(MSE, 2009b) at the same time as the 2008 Annual Report. The Project Summary was requested by CVRWQCB to support the agency's assessment of PG&E's recommendation for termination of the corrective action program and rescission of the WDR. As a result of CVRWQCB review of the 2008 Annual Report and information provided in the Project Summary, a request to rescind the WDR was placed on the uncontested items calendar of the agenda for the April Public Meeting of the CVRWQCB (CVRWQCB, 2009). At the meeting on April 24, 2009, CVRWQCB rescinded the WDR. Attachment 1 to this report provides a May 5, 2009 letter PG&E received from CVRWQCB that adopts the rescission of the WDR by Order No. R5-2009-0057 attached to the letter. CVRWQCB stated in the letter that groundwater monitoring and reporting were no longer required and that the monitoring wells could be scheduled for destruction contingent on approval of a work plan and permits by SJCEHD. SITE RECONNAISSANCE As a first step in the well decommissioning process, on May 21, 2009 MSE performed a comprehensive site reconnaissance. The objective of this reconnaissance was to confirm the presence, locations and conditions of monitoring wells and piezometers at the site so that a Request for Bid could be prepared for potential drillers. The reconnaissance also had the objective of confirming the presence, locations and conditions of other monitoring devices (i.e., staff gauges and water supply wells) that have been used in the past for various purposes. The site reconnaissance confirmed that all but two of the 26 monitoring wells and piezometers that had not been previously destroyed were present at the surveyed locations shown on figures submitted in recent years to CVRWQCB. The two piezometers that were not found are P-6A and WP-1 (called a"well point"rather than a piezometer). Figure 1 shows the locations of these monitoring wells and piezometers (except for five temporary piezometers, which are shown on Figure 2), and Table 1 summarizes known well and piezometer construction details previously presented and as modified by the site reconnaissance. Three of the wells (MW-1RD, MW-3 and MW-9) were surrounded by soil mounds of varying sizes. These wells were installed before pond closure, so it was surmised that PG&E decided to retain the wells after pond closure rather than decommissioning them and installing new wells. In addition, a fourth subsurface conduit with a soil mound was found to the east of the former Pond 3 location. This conduit was not present on previous figures available to MSE and its purpose was unknown. Figure 2 shows the locations of these wells and the unknown conduit and their associated soil mounds. The total volume of the soil mounds was initially estimated at about five cubic yards.