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EXHIBIT G -WATER INFORMATION r_ .. ,~ .: ~:~~ _. . ~t .. i _~s .=:xi5i ~~i i ...'.vF'vn d A%~.~._~IYe L:3S ..w-Y.HC This exhibit summarizes the potential direct effects to surface and groundwater systems under this amendment. The following subsections are included in this exhibit: • Surface water, • Floodplain, • Wetlands and waters of the U.S., • Groundwater, • Water requirements, • Water sources and water rights, • Temporary substitute supply plan, and • Water discharge permit. Surface Water Local surface water resources in the vicinity of the project are shown on Exhibit B-1. The nearest watercourse to the site is the South Platte River to the west of the property. The elevation at the center of the property is approximately 5,008 feet above mean sea level (AMSL). Based on the topography of the site, the property generally drains to the west towards Segment 15 of the South Platte River. This segment of the river has been designated "Use Protected" and classified for the following uses: Recreation, Class la; Aquatic Life; Class 2 (Warm); Water Supply; and Agriculture. Over 25 years of mining activities at the Worthing Pit have produced three pit lakes, totaling approximately 57 acres as shown on Exhibit G-1. Pit Lake I is 44.5 acres, Pit Lake 2 is 9.5 acres and Pit Lake 3 is 3-acres. Per Technical Revision (TR 9/84), dated September 7, 1984, the approved reclamation plan includes a total lake surface area of approximately 27.5 acres to remain with no backfilling at mine closure. TR-2, dated November 28, 2000, authorized dewatering and then dry mining of the pit lakes at Worthing Pit. Under this amendment, a total of approximately 57 acres of total lake surface will remain at closure of Worthing Pit. The pre-1981 total exposed lake surface area for the amended permit area is approximately 28 acres. Under this amendment, an additional 50.3 acres within the Expansion Area will be dewatered and then dry mined. Of the total 28 acres of pre-1981 exposed lake surface area for the amended permit area, the Expansion Area North had a pit lake of approximately 3.6 acres. This small pit lake at the Expansion Area North will be backfilled at mine closure. Depending on geologic conditions, two reclamation plans (Reclamation Plan A and Reclamation Plan B) are being considered as shown in Exhibits F-1 and F-2, respectively. As shown in Exhibit F-1, the Expansion Area North will be filled to a minimum elevation of 4,898 feet AMSL, at least two feet above the average groundwater elevation of 4,996 feet AMSL. Backfill material from deepening the WSF will be used to backfill the Expansion Area. Overall, the site will slope gently from east to west towards the South Platte River, and there will be no slopes steeper than 3H:] V. 1898-Frei 112 Exhibrts_(4.20.05).doc G-I