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Groundwater Monitoring & Response Plan <br />conjunction with well - specific details to assess the potential for projected water level declines to <br />impact a given water user's ability to obtain water from his or her well. The response and <br />mitigation process will be initiated immediately when, based on impact assessment findings, the <br />water level in a specific well is projected to drop to a level that will limit use of the well as a <br />domestic water source. The response and mitigation process is further discussed in Section 4.2 of <br />this Plan. <br />4.1 Impact Assessment <br />Prior to the start of dewatering each year, Elam will contact the owners of selected private wells <br />in the vicinity of the Pit and request authorization to access their wells to obtain water level <br />measurements using a hand -held water level indicator. The water level measurements will be <br />used to establish baseline conditions in the residential areas immediately surrounding the Pit; the <br />objective is to measure water levels in at least one well within each area. The pre - dewatering <br />water level data for the private wells (including the McGarry Well) and the four new monitoring <br />wells will be used to establish initial conditions for the groundwater model each year. <br />During active dewatering, Elam will use the water level monitoring data reported for the <br />McGarry Well and four new monitoring and two stream gages, model forecasts, and well <br />information to assess the potential for impacts to groundwater wells in the area. Specifically, <br />Elam will actively assess the potential for impacts by projecting future drawdown based on water <br />level monitoring data, assess how the water level change has influenced the available head at a <br />given well, and how the existing water level compares to the likely pumping level and/or the <br />bottom of the well; the numerical groundwater model will be updated as necessary to assist with <br />forecasting. The response and mitigation process will be initiated immediately when, based on <br />impact assessment findings, the water level in a specific well is projected to drop to a level that <br />will limit use of the well as a domestic water source. <br />4.2 Response and Mitigation Process <br />The response and mitigation process will be implemented in a step -wise approach. Step 1 will <br />involve verification of the projected threat. If the threat is verified, Step 2 will be initiated during <br />which adjustments will be made at the pit to mitigate the threat. If the threat cannot be <br />successfully mitigated during Step 2, mitigative measures will be implemented at the affected <br />Western Water S Land, Inc. 9 <br />