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Logan Wash Mine Annual Report Permit No.: M•1977-024 ] 4. Hydromulch seeding of the micro terraces, upper and lower benches, and the Research Mine Portal closure area. 15. Removal of the passive water treatment field-test cell and regrading of the area. The lower bench was regraded to accumulate material needed to construct the L-1 Portal earth plug. Additional material was mounded around and up to the level of the main valve vault; this material was seeded during revegetation work on the lower bench. The purpose of this valve vault is to control the flow of discharging mine water and retort water from the L-1 Portal workings and retorts. The vault at the Research Mine was constructed along the discharge pipe originating inside the mine. The top of the vault is at grade and within the contoured portion of the portal plug. The purpose of the vault is to access a butterfly valve to open and close the pipe and to monitor head within the mine behind the earth plug (with a manometer}. For further information, see Technical Revision No. 4 which discusses significant revisions to Exhibit E, the Reclamation Plan for Logan Wash Mine. 5.0 Maintenance Activities Maintenance activities included periodic inspections of mine roads, portals, underground drainage systems associated with the retorts and general mine workings, and evaporation pond security and leak detection system. Maintenance activities conducted at the mine and Pond 1 are summarized in the following sections. 5.1 Mine Maintenance During the reporting period, GSHI inspected the Logan Wash Mine site on a weekly basis. Inspection of the mine site was typically restricted to the surface areas of the mine benches, roads, and portals. Retort water levels and flow status were periodically checked in the mine. Underground inspections ceased in the fall of 2003 after the portals of the mine were sealed with earth plugs. Snow removal was periodically performed during the 2002-2003 winter on the lower access road to the SRB Cell and on the main access road to provide access for monitoring the SRB Cell and to retrieve equipment stored in the mine. No snow removal was conducted during the 2003-2004 winter. 5.2 Pond 1 Maintenance Maintenance of Pond 1 included inspection of (1) drainage rates to the pond from the mine retorts, (2) the leak detection vault, and (3) security fence and general conditions of the liner and pond. The teak detection vault was dry during the reporting period. Weekly inspections were conducted through November of 2003; monthly inspections have been conducted since that time. No other maintenance or repairs were performed at the pond, 6.0 Anticipated Reclamation in the Year 2004 With the exception of the upper access road, it is anticipated that the remaining disturbed acreage at Logan Wash Mine will be reclaimed in 2004. The upper access road, which is located on BLM land, may be left in place depending on the monitoring schedule and final solution to the Research Mine portal sea] and related mine drainage (see Technical Revision No. 4, February