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the violation of applicable water quality standards (4.05.18(1)(a)). The Division finds <br />that during and after mining, the water quantity and quality of the stream will not <br />be adversely affected (4.05.18(1)(b)). There would be no measurable impact on the <br />quantity of water in Munger Creek, which flows only a few times each year in <br />response to storm runoff and briefly in spring due to snowmelt. Water quality of the <br />stream will not be adversely impacted due to the requirement that drainage and <br />sediment control diversions. Investigations conducted by the applicant have <br />demonstrated that the proposed disturbances are outside of the 100 year flood plain <br />of Munger Creek. <br />Based on monitoring data from an alluvial well at the site, the stream is not recharged by <br />an alluvial water table in the project vicinity, precluding the possibility of contamination <br />of the stream via the alluvium. The Munger Creek stream channel will not be <br />temporarily or permanently diverted (4.05.18(1)(c)). <br />A. Diversions and Conveyance of Overland Flow <br />The collection ditches, diversions, and culverts conveying runoff from the disturbed areas <br />at the mine bench and along the Munger Canyon access and haul road will adequately <br />carrythe flow resulting from the 10 -year, 24-hour event. Ditches diverting undisturbed <br />flow, and conveying disturbed drainage from the coal waste disposal pile will adequately <br />carry the flow resulting from the 100 -year, 24-hour event. <br />B. Sedimentation Ponds <br />One sediment pond was approved and constructed to treat disturbed runoff from the <br />reclaimed coal mine waste disposal area (also referred to as the waste rock disposal site). <br />A plan view of the pond and associated drainage structures is depicted on Figure 2.2-6 <br />of the PAP, cross- section and specifications are depicted on Figure 2.2-7 of the PAP. <br />The pond was an incised impoundment with a design capacity of 0.75 acre feet. The <br />design included a 6" primary spillway pipe with a valve, installed at the maximum <br />sediment storage level, and a riprapped open channel emergency spillway at an elevation <br />four feet higher than the primary spillway inlet. <br />The sediment pond was approved for removal and reclamation after the Division <br />approved TR25. The pond was reclaimed, regraded, topsoiled and seeded in 2014. <br />C. Surface and Ground Water Monitoring <br />'11rfArA Wntar <br />The surface water monitoring program is addressed in Section 2.5 of the application <br />text, parameter list is presented in Table 2.5-2, and monitoring site locations are shown <br />on Figure 2.3-5. <br />Adequate baseline data indicating characteristics of water quantity and quality for East <br />16 <br />