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J. J. Dudash -2- October 13, 2009 <br />Predicted Rockfall Damage <br />3. Pages 2.05-109 states "Rockfall activity could damage and close roads and damage <br />structures. The structures at risk are the Operator's mine facilities. A large rock <br />rolling into one of the Operator's mine facilities could cause significant damage and <br />loss of life." <br />Mitigation <br />4. Page 2.05-116 states: "The Operator will protect its facilities from rockfall by <br />constructing one berm at the location shown on Map 15-2 and in accordance with <br />the design presented in Volume VII, Tab 11. No other protection measures are <br />proposed." <br />Additional Information: <br />5. The proposed mining does not pose a rockfall risk to the Operators facilities since <br />the proposed mining is located to the west of the facilities. <br />6. The coal to be mined is private coal under private surface both owned by BRL. <br />7. The first paragraph of page 2.05-4 states: "Room and pillar panels will be developed <br />off main and submain entries with barrier pillars left for protection. Partial pillar <br />recovery of all workings and barrier pillars will go on to the extent allowed by safe <br />mining and surface protection concerns." The proposed mining was anticipated by <br />this general statement. BRL does not believe any additional narrative is required to <br />describe the proposed mining. <br />8. DRMS Midterm Review: <br />The DRMS has a concern regarding outcrop failure as follows: "As documented in <br />the 2007 Annual Subsidence Report, a landslide had occurred in the Freeman Gulch <br />area in June 2007. Presumably, the landslide was a result of longwall mining on the <br />east end of the B-6 longwall panel. As was required in Exhibit 15 of Volume III and <br />shown on Map 14-B of Volume II, one row of pillars, 100 feet wide, of competent <br />coal had been left in place as an outcrop barrier pillar to prevent outcrop failure. <br />Since outcrop failure had occurred, please reexamine the issue of outcrop barrier <br />pillars and comment on whether or not more protection is needed." <br />BRL does not agree that outcrop barrier failure caused the June 2007 landslide. On <br />the east end of B-6 panel, the projected burn line is in excess of 500 feet blow the <br />surface. Both the B-Seam and D-Seam are burnt in this area. Many years ago the <br />burnt seams created a void space so the overburden lost its support and subsided. <br />The subsidence resulting from the burnt coal caused instability in the area of the <br />June 2007 landslide. Historic instability is documented on Map 08, Geologic Hazards, <br />which shows downward pointing arrows in the location of the landslide which