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Logan Wash Mine Annual Report <br /> Permit No. M-1977-424 <br /> discharge measurement of the mine water(former Colorado Discharge Permit System [CDPS] <br /> Outfall 001)and retort water; 2)semi-annual sampling of the mine-water discharge and retort- <br /> water discharge, groundwater at Wells LWCW-lA and LW-22A, and surface water at the Big <br /> Seep and Research Mine Tributary sample locations; 3)measurement of the manometer installed <br /> in the Research Mine Vault;4)precipitation; and 5)monitoring of the Evaporation Pond leak <br /> detection system; and 6)Daylight Bench stability monitoring. Monitoring data for the reporting <br /> period are shown in Table 4. <br /> 3.1 CDPS (NPDES) Permit Termination <br /> The CDPS permit for Logan Wash Mine(permit no. CO0048816)permitted two outfalls, Outfall <br /> 001 (Logan Wash Mine, main lower portal [L 1 Portal] discharge)and Outfall 002 (Research <br /> Mine discharge). During the 2014 reporting period, OOSI prepared Technical Revision(TR)No. <br /> 8 which proposed to infiltrate mine water discharge from the two existing CDPS outfalls as <br /> specified within the permit.DRMS approved TR No. 8 on January 23,2014. The CDPS <br /> application to terminate CDPS permit CO0048816 was submitted to CDPHE-WQCD on <br /> February 12,2014. CDPHE-WQCD approval for termination of the permit became effective on <br /> July 1, 2014. The mine water(Outfall 001)was conveyed with the retort mine water to the <br /> Evaporation Pond until May 12, 2015 when the mine water was diverted to the newly constructed <br /> infiltration trench. The infiltration trench was inspected and monitored during normal monitoring <br /> visits to the mine site through mid-November, 2015.The infiltration system functioned as <br /> anticipated with immediate infiltration and no ponding of the mine water in the bottom of the <br /> trench. The infiltration trench was backfilled on November 13,2015.Table 4 shows the results of <br /> monitoring data collected at the mine in 2015,and Figure 4 shows the results for the Outfall 001 <br /> flow meter(LW-001 mine water discharge). <br /> Outfall 002 did not discharge during the reporting period. Therefore, sampling under the CDPS <br /> permit was terminated with termination of the CDPS permit. <br /> For more information regarding the Research Mine portal closure and management of the <br /> Research Mine drainage see TR No.4 and TR No. 6,which present significant revisions to <br /> Exhibit E,the Reclamation Plan for Logan Wash Mine. <br /> 3.2 Mine-Water and Retort-Water Discharge <br /> Discharge measurements of mine water discharge(former Outfall 001)and retort water discharge <br /> were conducted on a quarterly or more frequent basis when access allowed. Continuous flow <br /> (meter)monitoring of Outfall 001 water came on line in August,2011 as part of a requirement of <br /> the former CDPS permit. These data were collected by OOSI to assess and evaluate mine closure <br /> effectiveness,to support operation and maintenance of the Evaporation Pond and future water <br /> management options, and meet state requirements.The flow meter is still operating and data are <br /> periodically recorded per the schedule described above. <br /> 3.3 Water Quality Monitoring <br /> Water quality monitoring continued at the mine site on a semi-annual schedule. Sampling was <br /> conducted of mine discharge waters,the mine water and the retort water, groundwater at two well <br /> locations, and surface water at two spring sites in May and October, 2015. Sampling of retort <br /> mine drainage water and mine water(former Outfall 001) is conducted to evaluate mine discharge <br /> water quality with time in support of final mine closure. The samples were collected from the <br /> retort water and mine water drainage pipelines inside the Lower Bench Vault. <br /> Western Water & Land, Inc. 6 <br />