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6Yest Elk Mrne <br />2.05.6(6)(f)(iii)(C)(I), with exception of the approximate 2.0 acre "Borrow Area". Consequently, <br />the area where the measures ~i~ill be implemented on the dam will not he reported as reclamation <br />work in the mine's annual reclamation report, and will not be subject to DBMS requirements for: <br />operation plans, sediment control, reclamation plans, reclamation bond, and the special public <br />notice requirements for affected areas ~rithin 104 feet of the outside right-of-~~~ay of a public road. <br />The '`Bon•ow Area'', howe~-er, d~•ill be subject to such reporting and requirements. <br />MCC in addressing 2.0~.6(6)(f)(iv)(A-D ), will complete preventative measures on Monument <br />Dam (Exhibit 76) and will do une or mc)re of the fnlluwing: replace, repair, and otherr~ise restore the <br />dam and struchu-es do~~nstream or will purchase insurance policies addressing downsU•eam damage and <br />will be in effect at the time of longwall mining, should catastrophic failure of the dam occur aS a result Ot <br />1111ne-IndUCed Impi3Ctti. flte d~llll dltd ddm fallUl'e hazards are addressed llt f3slllblt ~=1, alld al"~ <br />briefly mentioned here front the. Keith Bal:eman, Dam Breach Analysis of 2l8/8~, contained in <br />.rim Nortleet's letter to Grant Farnsworth, dated 11~[ay 2l, 1990: <br />"The clear ~~reather breach of Milutesota Dam (sic) produced a calculated <br />peal: Iluw at the dam of 10,280 cls. The peal: tlow was reduced to ~,2 i0 cfs by <br />the time it reached the mouth of [Viinnesota Creek at the North Furl: of the <br />Gunnison Ptiiver in Paonia. 9.8 miles downstream. The computed overbanl: <br />flooding depths vary fi'om 0. feet to 3.5 feet ilt the lo~~'er 6 miles of Minnesota <br />Creek, that contain 1'Uad CI'UJS1n~S and bUlldln~'S. Five gravel road crossings will <br />sustain damage, up to complete failure. Perhaps Dour houses will sustain shallow <br />flooding but loss of .life is not expected. These houses will experience water <br />damage tlp to structtu'al collapse, depending on the distance from the stream and <br />sU•eam movement clue to erosion. Computed flood velocities within the stream <br />channel ranged from 42 feet per second clown to 13 feet per second. The quantity <br />and velocity of flood ~~raters are expected to cause extensive erosion altd resource <br />dama~~e along Minnesota C'reel< and probably deposit a sediment bar in the <br />Gunnison EZiver (sic). <br />This evaluation of the clear weather breach indicates that the failure of Minnesota <br />Reservoir would probably not cause loss of life or excessive private or public <br />property damage. If a field chick of the flood plain supports the findings of this <br />reporrt, the hazard CI1SS111CatIUn of Minnesota Reservoir ~~~ill be reduced to <br />moderate. <br />"fhe clear ~areather breach of Minnesota Reservoir will: <br />1. Cause resource damage aloe, 9.8 miles of Minnesota Creek. <br />2. Damage five !ravel road crossings. probably completely breachins~ <br />the roads. v <br />~. Probably cut road access to 2U homes. <br />~. Damago 0-4 (sic) houses; some Wray eventually collapse front erosion of <br />th(:ll' IoLlndahUnl'.' <br />2.05-173 Rerr.cer(.lune ?005 PRII). Rein ,binrcb 2000: A/u)r 2006 PR10, R'or. 2006lIt107. ,4ugrrs~ 2007~RIOS <br />