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• <br />As planned in [he Proposed Closure Plan for Logan Wash Mine Retorts, the Logan Wash Mine retort water <br />was shut-in at the retort bulkheads on February 16, 2000. Tn the following months, head build-up in the <br />retorts resulted in noticeable leakage from the bulkhead areas of Retorts 7 and 8, the main rnntributors [o <br />retort drainage. It also was found that piping from Retort 7's bulkhead was not completely sealed and that <br />too high of head build-up within [he retort could result in discharge from the upper bulkhead piping. It was <br />also apparent that fracture flow from the shut-in retorts to nearby drifts and workings was also occurring <br />more quickly than anticipated. No channel flow of retort leakage was observed. Because of the greater <br />than anticipated leakage from the shut-in retort bulkheads, the retorts where reopened to drain to the <br />evaporation pond in July 2000. All mini-retorts remained shut-in. <br />There are ctrrrently no plans [o permanently shut-in the retorts as described in the Proposed Closure Plan. <br />Harding ESE is in the test and design phase of a passive water treatment system for the retort discharge <br />water. Sampling of the compliance well and mine-water discharge has continued on a quarterly basis (per <br />the Closure Plan) to support statistical evaluations of background water quality. <br />3.0 Disturbed Acreage Status <br />According to Exhibit E, [he Reclamation Plan for Logan Wash (1981), 134.7 aaes were approved for <br />disturbance within the permit area, and only 113.6 acres were actually disturbed. To date, it is estimated <br />that at least 25 aaes have been reclaimed at the Logan Wash Mine site. Most surface buildings and <br />sWctures have been removed and reclamation of those sites is complete. Surface swctures that remain <br />include a raise borehole and ventilation fan area, two vault structures (one on the lower bench and one at <br />the evaporation pond), a small section of exposed piping from the retort drainage pipeline, monitoring well <br />LW-112 (and possibly other wells), and Pond 1 (evaporation pond). During the reporting period, <br />approximately 6000 ft~ (0.14 aaes) was disturbed during repair of the retort discharge pipeline near the <br />evaporation pond. <br />4.0 Reclamation Activities im 2000 <br />No surface reclamation activities have been conducted at [he Logan Wash Mine site since the mid-1980's, <br />and GSHI did not conduct surface reclamation activities at the Logan Wash Mine Si[e during the last year <br />(March 23, 2000 to March 23, 2001). However, several other activities related to mine closure were <br />conducted. <br />S.0 Other Work Activities <br />Work activities conducted at the Logan Wash Mine during the reporting period included: (1) mine <br />maintenance, (2) well sampling in support of the retort closure plan, (3) Pond 1 maintenance, and (4) <br />compliance well installation. These activities are summarized in the following sections. <br />5.1 Mine Maintenance <br />During the reporting period, GSHI inspected the Logan Wash Mine site on a weekly basis. Inspection of <br />the mine site was typically restricted to [he surface areas of the mine benches, roads. and portals. <br />In September 2000, repairs were made to the retort discharge pipeline in a manhole vault, neaz the <br />evaporation pond. A crack had developed in the pipeline and some water was discharging into [he manhole <br />vault. <br />Several modifications were made to the retort drainage lines within the mine to provide effective drainage <br />of retort water. <br />