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Ms. Anne C. Conner September 22, 2009 5 survey coordinates for WP-1 but listed P-6A as "destroyed". The PG&E surveyor noted that the P-6A riser had been knocked over and moved from the location where the piezometer was supposed to have been located. PG&E was able to locate and provide a pre-1999 facility drawing that showed P-6A, but it was unknown whether the P-6A location was based on accurate AutoCAD plotting of earlier survey data. On July 30, 2009 MSE provided oversight to resurveying of WP-1 based on the October 25, 2000 survey coordinates. However, the coordinates provided for WP-1 in the PG&E survey were transposed with other well coordinates, and using triangulation from plotted well locations from a recent AutoCAD drawing to attempt to locate WP-1 proved unsuccessful. The surveyor then used a metal detector over a widespread area to attempt to locate any metal casing from WP-1 that might remain in the subsurface, but he was not able to detect any metal. It was concluded that the mangled metal casing found near to where WP-1 was previously located was the only remnant of the well point, and when it was knocked over (likely by a farmer) any additional casing that might have been present was inadvertently pulled out and dragged to the location where the mangled casing was found or was completely removed from the area. Also on July 30, MSE provided oversight to utility clearance at the site. Underground Service Alert cleared utilities into the site (Ticket#0231140) and MSE subcontracted a private utility locator to clear utilities within a six-foot radius around the 24 existing wells and piezometers that would be decommissioned. Because MSE was not able to locate P-6A by shallow digging in a small rectangle around the plotted location on the PG&E facility drawing, the private locator cleared a 4' x 200' area centered at the drawing plot for P-6A but mostly outside of two roadbeds within this area. The private utility locator found a PG&E gas line about four feet from monitoring well MW-11 (see Figure 2). MW-11 was about 98 feet deep and was installed using a 12-inch steel conductor casing to seal off the upper water-bearing zones. In order to safely cut off the conductor casing 2.5 feet below ground surface(bgs) in accordance with SJCEHD standards (SJCEHD, 2005), MSE recommended use of a non-sparking saw. SJCEHD agreed with this approach (SJCEHD, 2009c). WELL DECOMENUSSIONING AND SITE CLOSURE FIELDWORK: PHASE I From August 3 through 5, 2009 MSE conducted an initial phase of decommissioning and site closure fieldwork. In accordance with PG&E protocol and the MSE Health and Safety Plan (MSE, 2009d), RSI and MSE field staff viewed the PG&E safety video for the site and then attended a"tailgate" safety meeting conducted by MSE. On August 3, 10 wells and piezometers were decommissioned in accordance with SJCEHD standards (SJCEHD, 2005). These wells were decommissioned in the following order: TPZ-1 through -4 (Figure 2), and P-1A, P-1 B, MW-10, P-2A, MW-5 and MW-2 (Figure 1). The field crews completed pressure grouting of MW-11 and excavation of adjacent soils for installation of the mushroom cap, but the crews were unable to cut off the steel conductor casing to 2.5 feet bgs without using a non-sparking saw. The hole from excavating soil