Laserfiche WebLink
SepterrLrr 2004 BTUEnIoim Capvrabat "LiabiliryRe'eueApplunriot ~ Pabe3 <br />2.0 LIABILITY RELEASE REQUEST <br />2.1 LIABILITY RELEASE AREAS <br />Release of liability for surface subsidence effects due to underground mining is requested for <br />approximately 665 acres overlying the 5 Mine arorldrrgs to the west of State Hrghway 13. The <br />proposed liability release area, as delineazed on Map 1, does not include any alluvial valley floors, <br />croplands, or prime farmlands. Table ], Eagle No. 5 Mine -Liability Release Areas, provides a legal <br />description of the subject lands. <br />TABLE 1 <br />EAGLE N0.5 MINE -LIABILITY RELEASE AREAS <br />Liability Release Area Approx, Acres <br /> Within Permit <br />T6N, R91 W, Section 31 <br />SWYaNW'/a 44 <br />WYzW'/zSE'kNW'k 13 <br />SWYaSW',6NW'kNW'/a 4 <br />a portion of the NW'kSWYa 29 <br />a portion of the W'/zWYzNE'kSW'k 8 <br />a portion of the W'/zSW'/aSW'k 20 <br />a ortion of the NEYaSW'k 2 <br />T6N, R92W, Section 25 <br />S'/zSE'k 81 <br />S'/zN'/zSE'k 20 <br />SE'kSW'/a 40 <br />E'/zSW Y<SW'k 20 <br />S'/zNYzNE'kSW'/a 10 <br />SYzN'/zE%zNW'/aSW'k 5 <br />T6N, R92W, Section 35 <br />EYz EYzNE'k 39 <br />E'/zNE'/aSE'k 18 <br />T6N, R92W, Section 36 <br />N''/z less areas outside the permit boundary in the NEYa 180 <br />N''/zSW'/a 82 <br />TOTAL 615 <br />2.2 DOCUMENTATION FOR LIABILITY RELEASE <br />Mirvrrg operations in the 5 Mine on the west side of State I~ighway 13 were generally limited io <br />advance room and pillar mining with very limited retreat mining, so pillars of coal remained behind <br />following completion of muring, to support the mine roof. Conversations with individuals familiar <br />with the 5 Mine operations indicate that the combination of geologic conditions and a massive <br />competent overlying sandstone unit resulted in very good roof conditions during muring, limiting <br />requirements for roof bohing and other ground control measures. Given that the western portion of <br />the 5 Mine was developed and operated during the early 1970's through the early- to mid-1980's, <br />current subsidence evaluation and monitoring requirements were not yet in place. Consequently, little <br />or no subsidence documentation is available for this area Based, however, on both historic <br />descriptions and recent visual inspections, little or no visible surface subsidence has occurred over the <br />5 Mine western worldrrgs. <br />Nomtally, surface subsidence associated with underground coal mines occurs within 3 months to 3 <br />years of undem~itring, with little or no subsidence occruring after 5 years. In this case, little or no <br />surface subsidence has been observed over the 5 Mine western worlflngs; no muting has occurred in <br />this area in approximately 19 years, and a u approximately 'l4 years beyond the nomlal maximum <br />period for subsidence to occur. <br />BTLTEnpireOt~rna~at "29S15RQZ 27Cbk Crm!?, C080467 "(970f 870-1712 <br />GEraNEr~au]OOI LWiSryRdQ,dr <br />8//LD/jmi <br />Retisg(- Qxdxr 2004 <br />