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C. Sedimentation Ponds <br />Sediment ponds are discussed under Section IV.J.1 Volume IV of the permit <br />application. <br />The applicant uses sedimentation ponds in all disturbed drainages to control the <br />increased sediment loads within the ephemeral drainages on the mine site. All <br />sediment ponds are designed to contain or treat the 10-year, 24-hour event and <br />safely pass the 25-year, 24-hour event, at a minimum. <br />An alluvial well field near the confluence of Scullion Gulch and the White River <br />was originally developed to supply water for mine operations. The 1984 <br />completion of Kenney Reservoir east of Rangely, Colorado inundated much of the <br />alluvial well field. Because the alluvial surface is almost completely submerged <br />by the reservoir, recharge to the alluvium is now instantaneous. Due to <br />inundation of the well field by the reservoir, and due to high salinity of the <br />alluvial well water, the operator pumps water directly from the White River into <br />an adjacent lagoon formed by the Kenney Reservoir. Approval to pump directly <br />from the raw water lagoon to the raw water system was affirmed in Permit <br />Renewal No. 2 in 1994. Only one alluvial well, Qal-5, located at the mouth of <br />Scullion Gulch, remains in use as a monitoring well. <br />The raw water lagoon is a semi-in situ impoundment that collects water from the <br />White River. The Division approved (MR-55) the construction of a dike that <br />separates Scullion Gulch drainage from the lagoon area. The location of the dike <br />and its access road are shown on Map 90 of the PAP. <br />D. Surface and Ground Water Monitoring <br />1. The applicant will conduct monitoring of ground water in a manner approved <br />by the Division. The ground water monitoring plan can be found in Section <br />II.C.31, Vol. I of the permit application (4.05.13(1)). <br />2. The applicant will conduct monitoring of surface water in a manner approved <br />by the Division. The monitoring plan was submitted under 2.05.6(3)(b)(iv) <br />and can be found in Section II.C.2.e of the permit application, Vol. I <br />(4.05.13(2)). Currently, surface water monitoring is limited to monitoring <br />required under the CDPS discharge permit, as necessary to demonstrate <br />compliance with water quality standards and effluent limitations pursuant to <br />4.05.2. Additional surface water monitoring, which had previously been <br />required, was terminated in 1997 pursuant to TR-47. <br />The Division has reviewed the surface and ground water monitoring plans as part <br />of the renewal process. These monitoring plans are adequate to monitor for the <br />development of impacts, if any should develop. The 2008 Annual Hydrology <br />Report stipulated that the point of compliance for 2007-2008 was monitoring well <br />Deserado Mine 31 June 18, 2009