1994-10-17_GENERAL DOCUMENTS - C1981017

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continuous release of mine drainage to remove the possibility of future catastrophic failure of the tunnel seals and resultant flooding at the townsite of Redstone, which lies downstream of the mine. This office never received a written copy of the plan modification and the details of the modification were obtained by phone conversation and correspondence with Mr. John A. Reeves, President of Mid-Continent. The actual tunnel sealing as carried out consisted of only a single set of seals just inby the tunnel portals. These seals were constructed on a double block wall with steel reinforcing to make them explosion proof to MSHA standard. The exterior faces of the walls are covered with a cement stucco. Continuous water drainage from the mine workings is provided for by a single 12" PVC pipe (located in the north tunnel) that collects the drainage at the point where the tunnel intercepts with the workings. Because of the likelihood that this exposed pipe will be severed or crushed by rock fall in the workings or tunnels over the long term, a concrete "dam" was constructed just inby the north portal seal to act as a collection sump should the drainage no longer be contained in the pipe inby this point. The pipe is perforated adjacent to this dam to allow the water to still exit the main bulkhead via the pipe. It is unlikely that any damage to the pipe will occur in the short section between the dam and the outer portal bulkhead as this section is supported by heavily shotcreted steel arches. As an additional backup drain, each bulkhead was built with a 6" drain pipe at the base of the bulkhead. Based on what was seen in the on the ground inspection, and from information gained in conversations with MSHA, DMG, and Mid-Continent Resources officials, I believe that access to the Federal coal on the nine Mid-Continent leases has been properly abandoned. Ed Ginouves GJRA Mining Engineer