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Exhibit G -Wafer <br />If the geologic conditions are suitable, Pit Lake 1 and Pit Lake 2 at Worthing Pit will be <br />combined to create a WSF, enclosed by a liner, and deepened to increase its capacity. Deepening <br />of Pit Lakes 1 and 2 will generate material that will be used to back£I] Expansion Area North to <br />the final contours as shown in Exhibit F-2. <br />If all of both Pit Lake 1 and Pit Lake 2 are converted to a lined WSF, there will be minimal <br />infiltration of groundwater and negligible groundwater exposed to evaporation. The WSF will be <br />at least 45 acres. Should the WSF not use al] of Pit Lake 1 and Pit Lake 2, no more than the pre- <br />198] total surface area of 28 acres will be lefr exposed to evaporation at closure of the amended <br />permit area (Worthing Pit and the Expansion Area) without an approved water augmentation <br />plan. <br />Should the WSF be constructed, the liner will be designed and constructed per the guidelines of <br />the Colorado Department of Natural Resources, Division of Minerals and Geology Guide to <br />Specification Preparation For Slurry Walls and Clay Liners as a Component of A Colorado <br />Mined Land Reclamation Permit, September 2000. The liner construction will be approved by the <br />State Engineer's Office. All permanent pit lake embankments will be graded to a maximum <br />3H:1 V slope with a top elevation to match surrounding topography. Because the liner will ensure <br />minimal infiltration of groundwater, the impacts to local groundwater wells will be negligible <br />during dewatering of Worthing Pit after the installation. <br />Pit Lakes 1 and 2 will he dewatered prior to construction of the liner. Dewatering operations <br />would occur after August for approximately six months or until slopes for the liner are built. <br />When the liner is completed, minimal affects to the local groundwater wells will occur and <br />dewatering of the WSF will begin. After the State Engineer's Office approves that the WSF has <br />been properly constructed, the WSF will be deepened to finish reclamation of the Worthing Pit <br />and Expansion Area North. The area surrounding the WSF will be graded to match the <br />surrounding topography, topsoiled and revegetated. <br />Existing Pit Lake 3 at the Worthing Pit has been reclaimed as a pond and is currently used for <br />fishing. Pit Lake 3 will not be disturbed under this amendment. <br />Dewatering will be required for dry mining of the Expansion Area North. Dewatering water will <br />be routed to the settling basin, allowed to settle, and then discharged into the South Platte River <br />under existing Colorado Discharge Permit System (CDPS) Permit No. COG-500233. The <br />existing discharge permit will be updated to include the proposed Expansion Area. <br />No direct off-site discharge of surface water runoff from the disturbed areas or stockpiled <br />material is planned. Surface water runoff from the Expansion Area will be routed towards the <br />excavated area and will be retained onsite within the pit. Any storm water or groundwater <br />entering the disturbed area will be pumped into the settling pond and allowed to settle prior to <br />off-site discharge using existing CDPS Permit No. COG-500233. A Storm Water Management <br />Plan (SWMP) was previously prepared for the Worthing Pit and will be updated to include the <br />mine Expansion Area. Surface water will be managed both during mining and reclamation using <br />several control methods and best management practices (BMPs) as needed. <br />Existing on-site erosion and sedimentation control structures will be used for the Expansion Area. <br />Any storm water or groundwater entering the disturbed area will be allowed to settle prior to off- <br />site discharge using existing CDPS Permit No. COG-500233. <br />1898-Frei 112 Exhibi[s_(4.20.05).doc G-2 <br />