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<br />Logan Wash Mine Annual Report <br />Permit No.: M-t977d24 <br />downgradient of the main mine site during a site walkthrough with BLM representatives. Other <br />monitoring wells may exist, however, none have been located during several field investigations. <br />No new disturbed acreage was created during the current reporting period (see Section 4). <br />3.0 Monitoring Activities <br />Monitoring activities at the Logan Wash Mine during the reporting period consisted of mine <br />water discharge monitoring and sampling activities including, (1) two National Pollution <br />Discharge Elimination System (NPDES) outfalls monitored on weekly, monthly, and quarterly <br />schedules, (2) measuring flow rates of the mine-water discharge and retort-water discharge on a <br />weekly basis, and (3) monitoring flow and field parameters and sampling and analysis of influent <br />and effluent from the pilot passive-water-treatment system. <br />The former Closure Monitoring Program required by DMG under Technical Revision No. 2, <br />Proposed Closure Plan for Logan Wash Mine Retorts (TR-2) has been discontinued because <br />GSHI conducted the required 5-quarter sampling events at Well LWCW-lA and the mine water <br />(Outfal] 001). The closure program was ultimately abandoned due to leakage from the retorts. <br />For more information on TR-2, see previous annual reports. <br />Sampling at Well LWCW -1 A will resume, if necessary, when apassive-mine-water-treatment <br />system or other "discharging" solution is implemented at the mine. Once data from the sampling <br />events has been reviewed and are used to establish numeric protection levels (NPLs), an altemate <br />sampling schedule will be established for the remainder of the closure monitoring period. This <br />altemate schedule may be modified to accommodate construction and implementation of the <br />planned passive water treatment system or other closure alternative. <br />3.1 NPDES Outfall Sampling <br />Two NPDES outfalls, administered by the Colorado Department of Public Health and <br />Environment (CDPHE), were sampled in accordance with permit-established schedules. Outfalls <br />001 (Logan Wash Mine, main lower portal discharge) and 002 (Research Mine discharge) were <br />monitored weekly for pH, flow rates, total dissolved solids (TDS), and total suspended solids <br />(TSS); monthly For TDS, TSS, pH, nitrate, sulfate, fluoride, ammonia, COD, boron, oil and <br />grease, and phenols; and quarterly for TDS, TSS, pH, nitrate, sulfate, fluoride, ammonia, COD, <br />boron, arsenic, copper, lead, oil and grease, and phenols. Sampling was not conducted at Outfall <br />001 because of no-flow conditions at the designated outfall point. Sampling was also not <br />conducted from late June 2002 through March 2003 at Outfall 002 due to no-flow conditions. <br />Monitoring data were reported to CDPHE as required. <br />3.2 Miae-Water and Retort-Water Discharge <br />Measurements of clean (non-retort) mine-water discharge and retort-water discharge are <br />conducted on a weekly basis when possible. These data aze being collected by GSHI to support <br />the evaluation of alternatives for mine water treatment and mine closure. <br />3.3 Pilot Passive Treatment System <br />In November 2002, GSHI constructed a small pilot passive-water-treatment system consisting of <br />asulfate-reducing bioreactor (SRB Cell) (see Section 4). Monitoring of this system consists of <br />Western Water t4 Land, Inc. <br />DMGLWann103.doc <br />316/2003 <br />2of5 <br />