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near the evaporation pond. No new disturbed acreage was created during the current reporting <br />period. <br />3.0 Monitoring Activities <br />Monitoring activities at the Logan Wash Mine Site during the reporting period consisted of <br />monitoring and sampling activities: (1) two National Pollution Discharge Elimination System <br />(NPDES) outfalls on weekly, monthly, and quarterly schedules, (2) sampling ofmine-water <br />discharge and monitoring of groundwater (Well LWCW-IA) downgradient of the site under the <br />previously established Closure Monitoring Program, and (3) measuring flow rates of the mine- <br />water discharge and retort-water discharge on a weekly basis. <br />31 NPDES Outfall Sampling <br />Two NPDES outfalls, administered by the Colorado Department of Public Heahh and <br />Erndnronmerrt (CDPHE}, were sampled in accordance with peamit-established schedules. Outfails <br />001 (L.ogan 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, oii and grease, and phenols. Sampling was not conducted at Outfall <br />001 because of no-flow conditions at the designated outfaU point. Sampling was also not <br />conducted from later June 2001 through March 2002 at Outfall 002 due to no-flow conditions. <br />Monitoring data were reported to CDPHE as required. <br />3.2 Closare Monitoring Program States <br />In 1999, GSHI submitted Technical Revision 2, Proposed Closure Plan for Logan Wash Mine <br />Retorts (Closure Plan) to DMG. The Closure Plan outlined rationale and procedures for shutting- <br />in the mine's 5 main retorts where modified in situ oil shale retartitng had been performed in the <br />1980's. These rctorts collect varying amounts of infiltrated meteoric water and the resulting <br />discharge is piped to Pond 1, where it is passively evaporated. DMG approved the Technical <br />Revision and required that a Closure Monitoring Program be implemented to monitor <br />downgradiern groundwater and mine-water discharge quality during and after retort and mine <br />closure. <br />Well LWCW-lA was constructed (January 1999) as the downgradient monitoring poirn below <br />the lower mine bench in the bottom of Logan Wash drainage. The Logan Wash Mine retort water <br />was shut-in at the rctort bulkheads on February 16, 2000. Sampling began in February 2000 at <br />Well LWCW-1 A and at the clean (non-rctort) mine water discharge pipe. Under this program, <br />background sampling was to continue for at hest 5 quarters through at least June 2001, so that <br />numeric protection levels (NPLs) could be established. At the time the program was initiated, it <br />was anticipated that monitoring would continue up to 5 years (approximately March, 2005). <br />By July 2000, the retort bulkheads were showing greater than anticipated leakage and the <br />bulkhead valves were reopened and allowed to drain to the evaporation pond. The Proposed <br />Closure Plan under Technical Revision 2 was tberefare abandoned. However, sampling at well <br />LWCW-]A and the clean mine-water dischargewas continued in order to attain baseline data <br />needed for eventual closure under another Technical Revision at some time in the future. There <br />are currertly no plans to permanently shut-in the retorts as described in the Proposed Closure <br />Plan. GSHI is considering options in the design of a passive water treatment system for the <br />2 of 4 <br />