Laserfiche WebLink
3.2 Mine -Water and Retort -Water Discharge <br />Logan Wash Mine Annual Report <br />Permit No.: M- 1977 -424 <br />Outfall 002 (Research Mine discharge) is to be monitored monthly for pH, TSS, oil and grease, <br />arsenic, copper, cyanide (WAD), lead, molybdenum, selenium, uranium, boron, and chloride; and <br />quarterly for the additional parameters of TDS, mercury, and WET. Continuous flow monitoring <br />is required at both outfalls, but because Outfall 002 is shut -in and has not discharged for many <br />years, no flow monitoring or sampling has occurred under the new NPDES permit. <br />For more information regarding the Research Mine portal closure and management of the <br />Research Mine drainage see Technical Revision (TR) No. 4 and TR No. 6 which present <br />significant revisions to Exhibit E, the Reclamation Plan for Logan Wash Mine. <br />Discharge measurements of clean (non- retort) mine -water discharge (Outfall 001) and retort- <br />water discharge were conducted on a quarterly or more frequent basis when access and schedule <br />allowed. Continuous flow (meter) monitoring of Outfall 001 water came on line in August 2011. <br />These data were collected by OOSI to assess and evaluate mine closure effectiveness, to support <br />operation and maintenance of the Evaporation Pond, and future water management options, and <br />meet state requirements. <br />Sampling of retort mine drainage water and mine water ( Outfall 001) was conducted in June and <br />October 2012 to evaluate retort water quality with time in support of eventual mine closure. The <br />samples were collected from the retort drainage pipeline inside the Lower Bench Vault. The <br />analytical results for samples collected during the reporting period do not indicate a significant <br />improvement of retort water quality compared to past sampling events. <br />3.3 Research Mine Manometer Monitoring <br />The manometer installed in the Research Mine Vault is monitored and recorded on a weekly basis <br />in the spring months of April and May, or until the peak reading begins to subside; the <br />manometer is monitored at least quarterly at all other times. If manometer measurements were to <br />indicate a very thigh (> 36 inches) reading for more than a week's time, the water in the mine can <br />be released and sampled according to the NPDES schedule. The manometer level recorded during <br />2012 ranged from 10.5 inches to a high of 14.125 inches. <br />3.4 Evaporation Pond Leak Detection System <br />Monitoring of the Evaporation Pond Leak Detection Vault is conducted by continuous <br />measurement of water pressure (depth) in the vault sump using an installed pressure transducer. <br />On -site monitoring is conducted twice monthly as access conditions allow. Figure 4 shows the <br />pressure transducer water depth results for the period October 2011 to March 2012. During the <br />reporting period, the pressure transducer log indicated that the Leak Detection Vault received <br />water and was automatically pumped down on November 18, 2012. Based on observations of <br />suspended buckets under the three collection pipes, it appeared water had entered the vault <br />through the east drainage pipe. An inspection in January, 2013 showed the Detection Vault sump <br />to be full of water — the automated pump had malfunctioned and had not evacuated the sump. A <br />follow -up visit to repair the pump indicated that the float switch had not switched on; the pump <br />was adjusted and the sump was evacuated of water. In February, 2013, a similar event occurred <br />and the pump had to be adjusted again. In March, 2013, the old pump was replaced, and the solar <br />batteries were re- charged after showing insufficient voltage. The automated pump system is now <br />working correctly. <br />Western Water & Land, Inc. 5 <br />