2013-12-09_REVISION - C1982056 (2)

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12/10/13 State.co.us Eecutive Branch Mail - Re: Renewal App. No. 6(RN -6) Foidel Creek Permit No. C - 1982 -056 with regard to sound abatement through another permit issued by another agency, that agency would be responsible for enforcing the requirements of said permit. In terms of your mention of the the Colorado general standards and a reference to those standards, the Division of Reclamation, Mining, and Safety has jurisdiction to regulate only permits issued under the Law and Act of the Colorado Surface Coal Mining Reclamation Act. Concerning the issue with regard to "house shakes ", in your email dated November 19, 2013 it was stated that: Secondly sense June we have experience "house shakes ". At four time where we present to document the time and date of the shake. Giving the mine the benefit of the doubt" checked out the possibility of correlations with extremely small earthquakes. There were none. Based on discussions with geotechnical engineers familiar with long wall mining it is our understanding that the shakes were most likely cause by tunnel /shaft collapses during the mining operation. We are asking that as a condition of the permit's renewal that mining operations be changed to prevent the earth shakes that are affecting our home. The Foidel Creek Mine utilizes a mining process known as longwall mining to extract coal from what is known as the Wadge Coal seam - -1,100 to 1,400 feet below the surface. The process of longwall mining includes the development of main entries for access and ventilation. Thereafter groups of three parallel entries are driven perpendicular to the main entry on either side of the proposed extraction area (longwall panel). The width of the panel at the Foidel Creek Mine is 1,000 feet , and the length of the current active panel is - 10,000 feet. The coal is cut by a shearer which travels up and down along the face of the coal seam. Hydraulic self advancing shields support the roof at the immediate face as the coal is removed. As the face advances, the roof strata is allowed to cave in behind the shields; and results in what is known as planned surface subsidence. Prior to the Division's approval of longwall mining in the current Western Mining District, Twentymile Coal, LLC provided the Division with a Subsidence Report which included a worst case scenario prediction of subsidence based on the depth of overburden, the height of the coal seam to be mined, and type of overburden strata to determine a subsidence profile and determination of an angle of draw. Based on the approved prediction model and the extensive past monitoring program, the predicted subsidence of a maximum of --6 feet at the center of the panel and has been accurate. Based on a maximum 21 degree angle of draw, the entire worst case area of subsidence is 1,000 feet from the center line of the panel. Based on the Division's review the Mitzelfeld surface property boundary is 1,200 feet from the nearest mining area and the nearest structure identified on the Mitzelfeld property is - -2,100 feet from the nearest longwall mining location. The Division is very concerned if the identified "house shakes" have cause material damage to a structure or surface lands in which you are the owner. The Division is aware that Twentymile Coal, LLC have placed monitors around the Mitzelfeld property. Although the predicted subsidence has been accurate to date, anomalies may have occurred due to dip or strike of strata above or near the area of the fractured overburden. Although subsidence to structures does not warrant a change in mine plan, based on Rule 4.20.3(2)(b)(i) a mine operator must promptly repair, rehabilitate, restore, or replace damaged occupied residential dwellings and related structures or noncommercial buildings; or 4.20.3(2)(b)(ii) Compensate the owner of the damaged occupied residential dwelling and related structure or noncommercial building in the full amount of the diminution in value resulting from the subsidence. Compensation may be accomplished by the purchase, prior to mining, of a non - cancellable, premium prepaid insurance policy. hope I have adequately addressed some of your concerns. Based on history with surface owners in the area, the Division is under the impression that Twentymile Coal, LLC and the Foidel Creek Mine have been good neighbors throughout the life of mining. Unfortunately, the Division is bound by regulations, but I believe that voicing some of your concerns to Foidel Creek personnel my aid in alleviating some of the issues you have noted with the site. Please contact me with more information concerning possible damage to your property which could be associated with subsidence or any other comments or concerns you may have with the Foidel Creek Mine https: / /mai l.g oog le.conVmai 1 /u /0 / ?ui =2 &i k= e29129fcb5 &view = pt &search =i nboy&th= 142d96c646f35b87 2/5