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L.G. Everest, Inc. Carbon Valley Resource <br /> Exhibit G Addendum M-2001-017 <br /> Groundwater Monitoring & Mitigation Plan <br /> This information is prepared to lay out L.G. Everist's Groundwater Monitoring and <br /> Mitigation Plan for the mine. At this time there are no monitoring wells on the permit area. <br /> Previous data collected was for areas that have been released from the permit area and no longer <br /> applies to the current permit area. <br /> L.G. Everist, Inc. plans to install 4 ground water monitoring piezometers along the south, west <br /> and north sides of Area C. Included is a map showing the location of the proposed wells. The <br /> points were chosen because of the location of the surrounding shallow wells noted on Table G. <br /> The actual location of the monitoring wells may vary once they are installed and an "as built" <br /> map showing the exact location will be provided once the wells are in place. <br /> No wells are proposed for the existing area as it is surrounded on the east, northeast and <br /> north by three sealed reservoirs; to the south by a large irrigation ditch (Last Chance Ditch); and <br /> to the west by the operator's amendment property. Therefore, the reservoir liner on the existing <br /> side will have little to no effect, on any of the surrounding areas.. <br /> Groundwater Monitoring Plan and Data Analysis <br /> Once the wells have been installed in Area C, the plan is to begin collecting monthly data <br /> until two years of data has been collected. This period of time is chosen to collect two full <br /> seasonal cycles as it will establish background elevations from which the baseline and trigger <br /> points can be determined. As the data is collected it will be graphed and as mining may begin <br /> before the initial 2 years data is collected it will be important to review the trending depths to <br /> determine potential impacts to surrounding wells. During mining, the impact will be due to <br /> dewatering and a lowering of the water table within Area C. <br /> Data Collection and Submittal to the Division <br /> Monitoring wells that are around the perimeter of the operation will have data collected <br /> on a monthly basis through the initial 24-months. After the baseline period, the data collection <br /> will be done on at least a quarterly basis, unless a well's data exceeds baseline ranges, then data <br /> collection will revert to monthly until the variance is resolved. <br /> External wells will be checked for compliance to stay within baseline ranges, as changes at these <br /> wells could affect neighbors. The possibility of adjusting the baseline ranges if needed in the <br /> future will be discussed between the Division and the operator at that time. The baseline range <br /> changes would be documented with a Technical Revision. <br /> In the mine's annual report, the operator will give the Division a groundwater monitoring <br /> well data summary report that includes groundwater level data, times the trigger points were <br /> exceeded, investigations into cause, and any needed mitigation analysis/plans. The operator will <br /> also contact the Division with this information when/if a trigger point is reached and there seems <br /> to be a trend. <br /> 1 <br />