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<br />-31- <br />The applicant has provided an analysis of the effects of discharge of mine <br />water from New Elk Mine workings. This analysis indicates that although water <br />quality would be affected, the affect would not limit water use. The <br />applicant has also provided sufficient information and analysis to demonstrate <br />that the proposed mining operations beneath the Stonewall Valley would not <br />cause a significant loss of flow in the Purgatoire River stream-alluvial <br />aquifer system. The mining in the New Elk Mine beneath the Stonewall Valley <br />was determined to not cause material damage to the hydrologic balance outside <br />of the permit area. <br />The applicant does not have adequate hydrologic baseline data and analysis for <br />areas outside the Stonewall Valley. The Division is unable to make findings <br />about the hydrologic effects of secondary or retreat mining upon those areas <br />and whether the effects of mining would cause material damage. Therefore, <br />Secondary or retreat mining cannot be approved in those areas until the <br />applicant supplies sufficient information to make the required findings. The <br />Division can find that the proposed developmental mining operations have been <br />designed to prevent material damage to the hydrologic balance outside the <br />proposed permit area. <br />VIII Alluvial Valley Floors - Rules 2.06.8 and 4.24 <br />There are two alluvial valley floors (AVF) in the hydrological]y adjacent area <br />of the operations plan detailed in the permit revision. These AVF's are <br />located in Stonewall Valley (Middle Fork of the Purgatoire) and Picketwire <br />Valley (main stem of the Purgatoire). The original findings document details <br />the evidence far determination of the valleys as AVF's along with the <br />predicted impact by the New Elk Mine. The following discussion deals only <br />with the impacts predicted by the permit revision operation. <br />Stonewall Valley <br />A portion of the Stonewall Val]ey has been disturbed by surface operations at <br />the New Elk Mine. This includes the area within the disturbed area boundary <br />as shown on Maps 13 A-C of the original application. The disturbed area has <br />been determined to be "grandfathered" from the requirements of Rule <br />2.06.8(5)(a)(i)(A). Therefore, the Division is required to make a finding <br />that the proposed operation will restore the essential hydrologic functions of <br />the alluvial valley floor far that area contained within the disturbed area <br />boundary. <br />A large portion of the Stonewall Valley adjacent to the New Elk Mine has been <br />previously impacted by the disposal of coal processing waste. The alluvial <br />valley floor in the disposal area has been largely covered by the waste <br />piles. The waste piles were in existence prior to the enactment of the <br />Colorado Mined Land Reclamation Act, C.R.S., as amended, and the Division has <br />evidence that the areal extent of the waste pile disturbance was identical to <br />the present extent as early as November 5, 1971. Therefore, the areal extent <br />of the disposal area is pre-law. <br />