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1 w • <br /> 1 In summary, the monitoring wells were over-drilled with a drilling rig equipped <br /> with a guide bit positioned over the existing well casing. The total depth of the <br /> 1 over-drilled boring was approximately 21-feet below the ground surface (the <br /> constructed depth of each monitoring well/piezometer was approximately 20- <br /> feet). To the furthest extent possible, the PVC well casing was removed from the <br /> 1 borehole, and the boring was grouted to the surface with a neat cement mixture <br /> via tremmie pipe pumping the grout to the bottom of the boring and allowing the <br /> boring to fill from the bottom-up and flow to the surface. <br /> 1 2.6 Current Conditions at Destroyed Well Locations <br /> 1 Eleven previously existing Mossdale subarea wells/piezometers (TMW-1, TMW- <br /> 7, TMW-9, TMW-10, LMW-2, LMW-3, LMW-5, LMW-6, P-3, P-7 and P-8) could <br /> not be located and are presumed destroyed (Table 6). Ten wells/piezometers <br /> 1 were identified in the City of Lathrop's Well Installation Work Plan, and one <br /> piezometer (P-3) was destroyed and lost by construction activities since RWQCB <br /> staff approval of the Well Installation Workplan. Most of the destroyed <br /> 1 well/piezometer sites are now located in planned residential or commercial land <br /> use areas, whereas one well (LMW-5) is located near (but outside) the eastern <br /> 1 boundary of agricultural disposal field 52a (see Figure 2 for the destroyed well <br /> locations). <br /> 1 On multiple occasions, Kleinfelder personnel conducted a reconnaissance for the <br /> wells by physically canvassing the area and digging down with a shovel in an <br /> attempt to uncover remnant well casing. Kleinfelder also conducted an aerial <br /> 1 photograph search to document well locations relative to historical and current <br /> conditions. The results of Kleinfelder's field reconnaissance efforts and aerial <br /> photograph search are described in their August 31, 2005 letter to HydroFocus, <br /> 1 Inc. (Appendix F). On August 30, 2005 HydroFocus, Inc. visited the former sites <br /> to photograph current conditions. The results of Kleinfelder's and HydroFocus' <br /> reconnaissance efforts summarized below show that the former wells and <br /> 1 piezometers have been destroyed by farming or construction operations, and the <br /> former sites are all located beneath graded fill or roads and away from planned <br /> disposal areas. Hence, there does not appear to be significant potential for the <br /> 1 former wells/piezometers to serve as direct conduits for reclaimed water to reach <br /> deeper groundwater. <br /> 1 TMW-1 <br /> The estimated former TMW-1 site is located within a planned residential <br /> 1 development (Figure 2). On May 7, 2003 Kleinfelder representatives reportedly <br /> first noted that monitoring well TMW-1 had been destroyed. More than two years <br /> later (August, 2005), the estimated former TMW-1 site is located beneath graded <br /> 1 fill for future home pads, and the general area is currently used to store <br /> construction supplies and equipment (Figure 4). The remaining monitoring well <br /> PVC casing, if any, is assumed buried beneath graded fill. <br /> 1 . <br /> 1 <br />