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Segat~ei 2004 B7Z/ E»pire C1mLttiahm * LiabiliryRdvaseApla'.iaaim ~ Aare 3 2.0 LIABILITY RELEASE REQUEST 2.1 LIABILITY RELEASE AREAS Release of liability for surface subsidence effects due to undergrotmd mining is requested for approximately 665 acres overlying the 5 Mine worluttgs to the west of Staze I~ig}tway 13. The proposed liability release area, as delineated on Map 1, does not include any alluvial valley floors, croplands, or prime farmlands. Table 1, Eagle No. 5 Mine -Liability Release Areas, provides a legal description of the subjett lands. TABLE 1 EAGLE N0.5 MINE -LIABILITY RELEASE AREAS Liability Release Area Approx. Acres Within Permit T6N, R91 W, Section 31 SW'/a NW'k 44 W'hWYzSE'kNW'k 13 SW'/aSW'/aNW'/aNW'k 4 a portion of the NW'kSW'k 29 a portion of theW'hW'hNEYaSW'k S a portion of the W'/zSW Y<SW'k 20 a ortion of the NEYaSW'k 2 T6N, R92W, Section 25 S'hSE'k 61 SYzN'hSE'k 20 SE'/aSW'k 40 E'hSW'/aSW'k 20 S'hN'/zNE'/aSW'k 10 S'hNYsE'/zNW'/nSW'/a 5 T6N, R92W, Section 35 E'h E''/zNE'k 39 E'hNE'/aSE'/< 1 S T6N, R92W, Section 36 N'/z less areas outside the permit boundary in the PJEY< 160 NYzSW'k 82 TOTAL 615 2.2 DOCUMENTATION FOR LIABILITY RELEASE Mining operations in the 5 Mine on the west side of State I~ighway 13 were generally limited to advance room and pillar mining with very limited retreat mining, so pillars of coal remained behind following completion of mi^' a, to suppon the mine roof. Conversations with individuals familiar with the 5 Mine operations indicate that the combination of geologic conditions and a massive competent overlying sandstone unit resulted in very good roof conditions during mining, limiting requirements for roof bohing and other ground control measures. Given that the westem ponion of the 5 Mine was developed and operated during the early 1970's through the earl}F to mid-1980's, current subsidence evaluation and monitoring requirements were not yet in place. Consequently, lime or no subsidence documentation is available for this area. Based, however, on both historic descriptions and recent visual inspettions, little or no visible stuface subsidence has occurred over the 5 Mine westem woriflrtgs. Nomlally, surface subsidence associated with underground coal mines occurs within 3 months to 3 Yeats of underrrtittulg, with little or no subsidence occurring after 5 years. In this case, little or no surface subsidence has been observed over the 5 Mine western worlditgs; no mini ~ has occurred in this area in approximately 19 yEats, and it is approximately 14 Yeats beyond the normal maximum period for subsidence to occur. B7ZlEnyire Caprnaum * 295]5 RC7t 27 CLk Cam, CL780467 * (970f 870-2712 GE~mm2rgor/lON LialSryR6~e~ 8/igiWNjn Reusal- Clsdxr 2004