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Logan Wash Mine Annual Report <br /> Permit No. M-1977-424 <br /> Vault(LW-002); 4) precipitation; 5)monitoring of the Evaporation Pond leak detection system; <br /> and 6)Daylight Bench stability monitoring. Monitoring data for the reporting period are shown in <br /> Table 4. <br /> 3.1 CDPS (NPDES) Permit Termination <br /> The former CDPS permit for Logan Wash Mine(permit no. CO0048816)that permitted two <br /> outfalls,Outfall 001 (Logan Wash Mine, main lower portal [LI Portal] discharge)and OutfalI <br /> 002 (Research Mine discharge), was terminated on July 1, 2014. Any mine discharge from the <br /> former outfalls is being infiltrated into the Lower Mine Bench. For more information regarding <br /> the Research Mine portal closure and management of the Research Mine drainage see TR No. 4 <br /> and TR No. 6, which present significant revisions to Exhibit E,the Reclamation Plan for Logan <br /> 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 and data logger downloaded per the schedule described above. Table 4 <br /> shows the results of monitoring data collected at the mine in 2016, and Figure 5 shows the results <br /> for the Outfall 001 flow meter(LW-001 mine water discharge). <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 one spring site in May and October, 2016. Sampling of retort mine <br /> 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 /> Historical and 2016 analytical results for mine water(LW-001), retort water(LW-Retort), and <br /> Well LWCW-IA are shown in Tables 5, 6, and 7, respectively. The analytical results for samples <br /> collected during the reporting period do not indicate a significant improvement of retort water <br /> quality compared to past sampling events. <br /> One of the locations,"Big Seep", is considered to be a potential source water of mine water <br /> discharge. "Big Seep" emanates from the rock wall above the Daylight Portal and was sampled in <br /> May and October of 2016. In addition, samples were collected from Well LW-22A, an alluvial <br /> well located in Logan Wash located approximately 2.25 miles down Logan Wash from the mine. <br /> Samples of the retort water flowing through the Lower Manhole(LW-LM) were also collected. <br /> Locations sampled during the 2016 semi-annual sampling events are shown in Figure 6. <br /> Analytical data from all of these samples are shown in Table 8. <br /> Western Water & Land, Inc. 7 <br />