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Exhibit G - Waler Dust suppression at the crusher will be achieved by water spray during dumping, in a mostly enclosed dump hopper, and at conveyor belt transfers to maintain dust within regulated levels. Water for dust suppression on roadways and in the removal of overburden will be applied by water truck, as required. Dust suppression is estimated to require approximately 3 acre-feet per year. Total annual water depletion associated with the proposed mining operation is estimated to be approximately 100 acre-feet per year, which includes dust suppression as shown in Table Gl. After mining is completed, the existing lake at the Expansion Area North will be backfilled. After reclamation is completed, uo groundwater will be subject to evaporative loss in the Expansion Area. No irrigation will be required for revegetation. Under this amendment, the post-mining land use far the Worthing Pit will include two remaining lakes. Should a WSF be constructed, it will be at least 45 acres and the total surface area of the remaining lakes will be less than the exposed surface area prior to 1981. Water used to fill the WSF will come from water rights transferred from upstream and diverted from the South Platte River, and evaporative groundwater losses will no longer be an issue. Water Sources and Water Rights Acquisition of sufficient water rights to provide augmentation of the annual depletions for the proposed ]Wining operation are currently under negotiation. Under this amendment, the anticipated total net depletion for the mining operation is approximately 100 acre-feet per year. A variety of water sources will provide augmentation of a minimum of 100 acre-feet per year. The available water sources are more than sufficient to augment the proposed depletions for the mining operation. Should a lined WSF be constructed, it will be at least 45 acres. Water used to fill the WSF will come from water rights transferred from upstream and diverted from the South Platte River. Temporary Substitute Water Supply Plan A temporary substitute water supply plan for Worthing Pit was submitted for approval to the State Engineer's Office in 1990 (Bishop-Brogden Associates, Inc. 1990). An amendment to the previously submitted temporary substitute water supply plan is being prepared and will be submitted for approval to the State Engineer's Office. At the time of the 1990 water supply plan, the total surface area of the lakes was 41 acres and the estimated annual water depletion was 112,3 acre-feet. In letters dated February 6, 1991 and October 29, 1993, the State Engineer requested additional information on this plan. A letter dated December 1, 1993 from Albert Frei & Sons, Inc. to the State Engineer's Office indicated that the applicant is looking for a more reliable water replacement source for the plan. Per TR-2, dated November 28, 2000, a change from wet mining to dewatering and then dry mining was approved for Worthing Pit pending the State Engineer's approval of the temporary substitute water supply plan. To date, Worthing Pit has not yet implemented dewatering for dry mining. Under this amendment, additional substitute water supply will be required to dewater and then dry mine at the Expansion Area North. The 1990 temporary substitute water supply will be amended to include replacement of groundwater depletions during dewatering and dry mining at both Worthing Pit and the Expansion Area North. 1898-Frei 112 Exhibits_(4.20.05).doc ('i-1 O