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Mr. Peter O'Connor -5- July 14, 1986 1. Blue Flame Coal Mine will adopt the 21 degree angle of draw and a maximum overburden thickness figure of 300 feet proposed by the Division. It may be expected that subsidence features will be expressed on the surface up to 115 feet away fran the barrier pillar after mining is comq~leted. The permit boundary, i.e., the areal placement of the barriers, has been modified to ensure a 115 foot subsidence buffer. 2. Blue Flame Coal Mine has identified the Huntington ditch as the only renew- able resource existing on the surface above the permit area. Blue Flame Coal Mine has submitted a detailed map which overlies the mine plan. This map ac- curately depicts topography, existing roads, the Huntington ditch, ephemeral drainages, any existing strictures and the subsidence monitoring points as described in 3 and 4 below. 3. The proposed subsidence monitoring stations have been modified to accurately quantify movement. The proposed Southernmost point, point number 2, has been moved 200 feet West so it will not be affected by the inactive workings of the old mine. A fourth monitoring point, point number one, has been estab- lished 250 feet East of the Wbst permit boundary line and 110 feet North of the South permit boundary line. The Northernmost monitoring point, point number 4, has been moved 350 feet West of its proposed location. Point 3, the Northwestenurast point has not been changed from the proposed location. 4. One reference point has been established off any areas potentially affected by subsidence. Blue Flame Coal Mine has adopted the Division's recarmenda- tion that this monument be established at least 130 feet South of the face of the South barrier pillar and 150 feet West of the Westernmost extent of the old mine workings, 5. Monitoring of the subsidence monument network will take place at least twice prior to any underground development work in order to establish a base line data. This monitoring will take place after the Mined Land Reclamation Div- ision permit has been obtained and previous to approaching within 115 feet in any direction of any subsidence monument. 6. Blue Flame Coal Mine commits to a quarterly annual monitoring filing the first year and will continue monitoring on a quarterly basis throughout the life of the mine. 7. For purposes of reporting subsidence monitoring data, the following informa- tion will be provided on a semi-annual basis: a. Survey data which has been tabulated and reduced shall be submitted by the engineer. b. Five (5) subsidence profiles will be submitted. These profiles, which will be adequately detailed and certified by a registered professional engineer, shall extend between points 1 and 2, 1 and 3, 2 and 3, 2 and 4, and 3 and 4. Each point has been numbered as per the comment number 3 above.