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The United States Army Corps of Engineers has provided comments that no Army Corps permit is <br />required at the river diversion point provided the project does not cause a discharge of dredged or fill <br />material below the ordinary high-water mark of the Animas River or any of its associated wetlands. <br />rains e <br />The applicant provided a drainage study addressing stormwater management along the project access <br />road and CR 213. The site plan shows detention ponds serving dual functions of capturing stormwater <br />and managing operational water (recirculating material cleaning water and removing sediment). The <br />applicant represents that the ponds will not discharge any water and that the operator commits to <br />providing a minimum of 3 feet of freeboard in the ponds at all times. <br />Because stormwater is proposed to be comingled with operations water, a detailed evaluation of <br />operational projections is needed for this component of the project. The Colorado Water Quality <br />Control Division (WQCD) has a permit specifically for sand and gravel mining process water and <br />stormwater (COG-500000). The resulting permit will be a Colorado Discharge Permit <br />(CDPS), which is that State's equivalent of an NPDES <br />The WQCD has confirmed that it will review the project in detail. Staff's understanding of <br />the potential resulting permitted operations for water discharge from the site are as follows: <br />1. "No exposure". This means process water and stormwater will be mixed and <br />completely consumed on the site with no discharge. This represents condition <br />currently proposed by applicant; WQCD, however, reports this is very rare. <br />2. Stormwater permit only. This is possible if it is demonstrated stormwater will be kept <br />completely independent of process water and the only discharge from the site would <br />be stormwater. Process water would need to be completed consumed on the site with <br />no discharge. Stormwater berming and an outflow structure would need to be added <br />to the existing plaits. This represents a different scenario than currently proposed and <br />would involve edits to the current site plans. <br />3. Comingled stormwater and process water discharge permit. This permit allows the <br />mixing of waters and discharge of the waters from the site. It treats all of the water as <br />operational/industrial water and thus requires ongoing treatment and monitoring of the <br />water. An outflow structure for the mixed water would need to be added to the <br />existing plans. This represents a different scenario than currently proposed and would <br />involve edits to the current site plans. <br />Because the applicant is engaging the State mining (CDRMS) and WQCD permitting <br />processes subsequent to the county land use process, revisions to site plans based on the <br />States's review are anticipated. As such, a Condition of Approval is that revised site plans be <br />submitted to the county following receipt of state permits and prior to project construction. <br />Note that the BOR has particular concern with respect to the discharges from the site. The <br />area in which storage and treatment ponds are proposed is the area from which Animas-La <br />Plata (A-LP) project gravel was extracted. The area has been reclaimed and runs off and <br />down a grouted riprap channel to the Basin Creek (west of the project site) with Basin Creek <br />feeding the Animas River. BOR reports it has strict water quality standards it needs to meet <br />Project No. 2010-0055 <br />Animas Glacier Gravel Class II <br />DeleW: I <br />Page 7 of 21 <br />EA[r 1 <br />V,Jeenridnuclhe Construction Au ?i <br />,&.Nt Mp.S <br />G?A ?4 cP.7%r <br />r- LAGI Se- C- (2,AV E1.- <br />M- PA,6 e M - `? <br />