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<br />Proposed Decision and Findings of Compliance July 2018 <br />Permit Renewal No. 7 P a g e | 32 <br /> Prevent damage to fish, wildlife, and related environmental damages and prevent additional <br />contributions of suspended solids to streamflow or runoff outside the permit area (Rule <br />4.04(1)). <br /> Control and minimize diminution or degradation of water quality and quantity (Rule <br />4.04(2)). <br /> Control and minimize erosion and siltation (Rule 4.04(3)). <br /> Control and minimize air pollution (Rule 4.04(4)). <br /> Prevent damage to public or private property (Rule 4.04(5)). <br /> <br /> Minimize damage, destruction, or disruption of services provided by wells , pipelines, <br />railroads, electric lines, and telephone lines (Rule 4.04(6)). <br />III. Hydrologic Balance - Rule 4.05 <br /> <br />The Permit is found to be in compliance with the requirements of Rule 4.05. <br /> <br />A. Water Quality Standards and Effluent Limitations - Rule 4.05.2 <br /> <br />There are 12 outfalls currently approved at the Colowyo Mine. These outfalls correspond to <br />sediment ponds listed below in Section D. The outfalls are monitored for water quality as part of <br />Colowyo’s Colorado Discharge Permit System (CDPS) permit no. CO-00458161. The Division’s <br />review of Discharge Monitoring Reports associated with CO-00458161 indicated an exceedance <br />of limitations for Total Suspended Solids (TSS) at East Taylor Pond (outfall number 010A). Based <br />on a memorandum of understanding with the Colorado Water Quality Control Division (WQCD) <br />and the Division, the WQCD is responsible for enforcing CDPS permit conditions. No violations <br />were issued by WQCD in association with CO-00458161 during the 2012/2017 permit term. <br /> <br />Colowyo’s current CDPS permit and plan associated with the Collom Pit area is under review by <br />the WQCD. <br /> <br />Surface drainage from all disturbed areas passes through sediment ponds with some exceptions. <br />The Division has granted Small Area Exemptions (SAEs) for some areas on the mine site. SAEs <br />include the area along the East Side Collection Ditch, the topsoil stockpiles along Haul Road A, <br />and the East Taylor Holding Pond and pump station (shown on Map 11 and Map 12 of the PAP). <br />Additionally, a total of three areas are permitted as SAEs in the Collom Area. The SAEs include <br />a 1.4 acre zone along the east side of the pit in Section 1, a 7.66 acre area along the east side of the <br />pit in Section 2, and a 2.6 acre area on the west side of the pit in Section 34. These sites are <br />relatively small and analysis indicates that standard treatment facilities (i.e., large sediment ponds) <br />are not necessary for the drainage to meet the effluent limitations of Rule 4.05.2 and the applicable <br />State and Federal water quality standards for receiving streams. More information on SAEs can <br />be found in Exhibit 7 of Volume 18 of the PAP. <br /> <br />All disturbed area surface drainage in the South Taylor area will drain through sediment ponds; no <br />SAEs are approved in the South Taylor watershed (4.05.2(3)(b)(i)). Mixing of surface drainage