2004-03-26_REVISION - M1977424 (3)

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March 26, 2004 2. Yer~ that all banding was removed from the highwall and other surface areas. A subcontractor was hired to remove all surface rock-fall protection materials including chain- link netting, metal banding, and some metal anchor posts. A walkthrough conducted at the completion of the work verified that all metal banding was removed. Should any banding be discovered during the 2004 field season, it will be removed. Attachment A shows photos of the highwall areas before and during the rock-fall protection removal. DMG is welcome to inspect the area for the presence of metal banding. 3. Submit the revised/proposedwed mix and tubling transplant table for revegetation at the site. The seed mix and transplant tubling table is presented in Attachment B. The seed mix and tubling transplant table was verbally approved by Mr. Gregg Squire of the DMG in the summer of 2003. Mr. Squire recommended reducing several species and application rates presented in the initial proposed seed mix. Because the original and revised (TR No. 4) reclamation plan states that vegetated islands will be established on the mine dump slopes, full coverage of the dumps by vegetation is not planned. The hand-excavated "micro" terraces were installed in areas where composition of the dumps was favorable for establishing vegetation. W WL is transplanting tublings at a density of approximately one plant per 3 square meters (32 square ft). However, transplants aze more dense on the terraces than the inter-terrace areas. Generally, one tubling is planted every 4 to 5 linear feet along a given terrace, and 1 to 3 tublings are planted in the inter-terrace areas per 15 linear feet of terrace. Species types were alternated during planting. 4. Yer~ drat flood water that back-up in the Research Mine workings will not result in transmission ofwater to the L-1 Portal WWL believes that DMG has been provided with all relevant underground maps of the Research Mine and Lower Level (L-1) workings of the Logan Wash Mine. However, a map is presented in Attachment C. W WL conducted several reconnaissance visits to the underground workings in both the Research Mine and the Lower/intermediate levels of the Logan Wash Mine with the specific intent on investigating the connection of these workings. In addition, W WL, in implementing a safe underground working condition, set a number of safety lines inside existing manway raises. As the map in Attachment C indicates, the only workings discovered to connect Logan Wash Mine to the Research Mine were three mises including a manway raise collared in an upper drift (775 Drift) of the Research Mine. The Research Mine collaz elevation is at least 200 feet above the Lower Level of the Logan Wash Mine. This vertical distance was verified while setting safety lines down the manway raise. Furthermore, the Research Mine collaz elevation in 775 Drift is estimated to approximately be 75 ft above the level of the lower workings that flood. In the case that flood water from the Research Mine migrated to the Lower Level workings of the Logan Wash Mine, the existing French drain in the Lower Level workings should be able to accept the additional flow. During high mn-offyeazs, the mine water discharge from the French drain has exceeded 30 gallons per minute with no indication ofwater migrating toward the portal on the floor of the L-1 Drift. In addition, during the summer of 2003, W WL, in the case [hat the Lower Level receives an abnormal amount of recharge, installed an open drain standpipe at the head of the French drain. In the case that water floods the Lower Level workings at a rate greater than can be accepted by the French drain, the open 2-inch drain will convey mine water directly from the floor of the mine into the mine water drain pipe and out of the mine to discharge in Dry Gulch.