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`~ .,_ <br />Gu~~~9~1n~~oddG ~. <br />January 15, 2003 RE~~~~l~® <br />Mr. Jim Burnell ~AP Z ~ '~ <br />Environmental Protection Specialist <br />Colorado Division of Minerals and Geology DiYisianol MinaralsaadGanlayY <br />1313 Sherman Street, Room 215 <br />Denver CO. 80203 <br />Re: Oxbow Mining LLC, Permit No. C-1981-022, PR-OS Application, <br />Response to the Colorado Division of Minerals and Geoloav (CDMG), January 14. <br />_ _ 2003 Adequate letter. <br />Dear Mr. Burnell: <br />The purpose of this letter is to provide Oxbow Mining, LLC's (OMLLC) response to the <br />referenced PR-OS review correspondence from the Colorado Division of Minerals and Geology <br />(CDMG). <br />Comment #1-Plate numbering. ' <br />The plates'will lie. revised with riuinbered panels`arid;copies wilPbe forwarded Yo the Division. <br />Comment #2 -Subsidence features. Bear Creek. <br />The Division has requested additional information relative to the potential impact of predicted <br />subsidence of the Elk Creek mine on Bear Creek. <br />On pages 27 and 28 of the report Predicted "D"Seam Longwall Subsidence: Panel Group #1 for <br />the Elk Creek Mine by John F. Abel, Jr., January 6, 2003, (provided with the OMLLC January 7, <br />2003 submittal) the author provides extensive discussion and analysis regarding the predicted <br />effects of subsidence on areas of minimal overburden thickness. The author concludes that: <br />`A zone of downward deflected rock lies above the fractured and <br />fissured overburden to the ground surface. The permeability of this rock <br />should have decreased because it will be compressively strained rock by <br />the downward deflection of the subsidence trough, as shown on Figure 4. <br />Therefore, no water should ever enter the Elk Creek Mine through the <br />280-ft minimum overburden thickness between Bear Creek and Panel #1 <br />ofLongwall Panel Group #1. " <br />Further, the author states on page 47 that : _ <br />"The maximum predicted horizontal tensile strains at the ground surface <br />' will `result 'in open 'surface 'fractures roughly along'"and- nears the '-' ~' '~ '~'' <br />maximum tensile. (+E) srtain lines on Plate 4. The width of these open <br />fractures'will range from a fraction of an inch (1660 µe) to <br />3737 Hwy 133 P.O. Box 535 Somerset, Colorado 81434 USA <br />TEL (970) 929-5122 FAX (970) 929-5177 <br />