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Rationale for Recommendation to Approve <br /> Page 14 <br /> September 26, 2016 <br /> for approval of AM-01, received January 13, 2016, and September 20, 2016. DWR's conditions <br /> for approval included requirements for accounting of all inflow and outflow as necessary to <br /> demonstrate compliance with Colorado water allocation laws, and requirements to perform a <br /> final leak test, after installation of the drain pipes, to verify the integrity of the slurry wall. <br /> In a correspondence dated June 21, 2016, the Operator affirmatively stated operations were in <br /> compliance and will remain in compliance with DWR requirements. <br /> With respect to the second SEO comment expressing concern for the integrity of the approved <br /> slurry wall after the proposed drain installation, it is standard practice for the Division to notice <br /> the DWR prior to permit release for any lined reservoir. DWR will have an opportunity to object <br /> to the release of the permit if they feel that liner integrity issues have not been fully addressed to <br /> their satisfaction at that time. <br /> Therefore, AM-0I demonstrates compliance with the applicable requirements of Section 34- <br /> 32.5-116(4)(h) C.R.S., and Rule 3.1.6(1)(a). <br /> 3. Concerns that the permanent groundwater mounding mitigation plan as proposed <br /> )Pill not sufficiently reduce groundwater mounding and impacts to off-site property. <br /> (Equity Funding LLC—first and second comment periods) <br /> Pursuant to Section 34-32.5-116(4)(h) C.R.S., and Rule 3.1.6(1), the Operator must demonstrate <br /> how the mining and reclamation activities will be conducted to minimize disturbances to the <br /> prevailing hydrologic balance of the affected land and of the surrounding area and to the quantity <br /> and quality of water in surface and groundwater systems. <br /> In the February 29, 2016, adequacy letter to the Operator, the Division identified the average pre- <br /> slurry wall groundwater elevations for three monitoring wells up-gradient of the slurry wall and <br /> proximal to the location of the permanent groundwater mitigation plan activity(MW-2, MW-3, <br /> and MW-11 B). These average pre-slurry wall groundwater elevations were calculated from the <br /> monthly groundwater level monitoring data collected by the Operator from February 2004 until <br /> the slurry wall was completed in June of 2005. <br /> Based on this data, prior to the installation of the slurry wall at the site, the average groundwater <br /> elevation for monitoring well MW-2 was 5035.96 feet (5.63 feet below ground surface); well <br /> MW-3 was 5037.69 feet (10.58 feet below ground surface); and well MW-1 I was 5036.90 feet <br /> (2.63 feet below ground surface). The amendment proposes setting the invert (inlet) elevation of <br /> the Orr drain (located adjacent to MW-2) at an elevation of 5036.5 feet. This elevation is an <br /> additional 2.3 feet below the elevation of the current temporary drain, and is intended to lower <br /> groundwater levels in the area to approximate pre-slurry wall levels while still allowing for <br /> positive drainage into the completed reservoir at its design high water elevation of 5036.0 feet. <br /> The proposed Orr drain invert elevation (5036.5 feet) is below the average pre-mining <br />