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Geosyntec O <br /> consultants <br /> 4. WELL DESTRUCTION EVALUATION <br /> Initial assessment of potential wells to be destroyed as part of this Work Plan began with <br /> a review of the 2020 Request and general evaluation of the Site wide monitoring network. <br /> Based on the assessment, the following well groups were preliminarily identified as <br /> candidates for destruction: <br /> • Wells previously identified for destruction in the 2020 Request; <br /> • Piezometers located at the edge of the monitoring network; and <br /> • Wells previously used for Enhanced Reduction Dechlorination (ERD) injections <br /> completed in 2008, which are no longer used or monitored(LFR, 2008). <br /> The wells were then evaluated based on the following criteria, as shown on Figure 2: <br /> 1. Is the well included in the MRP or GWMP? - If so, for the well to be considered <br /> for destruction it must satisfy one of the following criteria to continue being <br /> evaluated for destruction: <br /> a. Is the well redundant (i.e., nearby well screened in the same zone <br /> providing redundant data)? <br /> b. Does the well exhibit stable or decreasing constituent of concern (COC) <br /> trends at low concentrations or below the Maximum Contaminant Level <br /> (MCL) for approximately 2 years? The well can additionally satisfy the <br /> criteria if it is not routinely monitored for COCs (i.e., ERD wells or <br /> piezometers). What constitutes "low" concentrations will be determined <br /> on a per well basis. Compliance wells are not eligible for destruction under <br /> this criterion. <br /> c. Is the well damaged or fouled beyond repair? <br /> 2. Is the well needed to define the plume extent or boundary? - This criterion <br /> evaluates whether the well is used for evaluating plume dynamics and is useful <br /> for defining the plume boundary during active remediation. <br /> 3. Is the well located within the remedy footprint?—This criterion evaluates whether <br /> the well is located within the current plume footprint,which is defined as any well <br /> located within the treatment zone. Per the WDR-MRP guidance, the treatment <br /> Well Destruction Work Plan 3 June 27,2023 <br />