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<br />DIVISION OF MINERALS AND GEOLOG"- <br />Duparlmenl of Natural Resource <br />1 3l 3 Sherman 51., pn,>m ? 15 <br />Denver, Culorado 40203 <br />phone: (1031 866 3 567 <br />FAY: (303) A32-4106 <br />Date: August 22, 1994 <br />Si-~ <br />STATE OF COLORADO <br />s ___ <br />~~ ,~ III IIIIII IIIIIII III <br />999 <br />~~_ ~I~~~ <br />DEPARTMENT OF <br />NATURAL <br />RESOURCES <br />Rov Rnmer <br />To: Harry Ranney ~~~ oa,emar <br />//, /~ ken Salazar <br />From: Kent Gorham K`\ e+ec°mr oirrri^r <br />l Nic hael B. Lang <br />CC: David Berry °ivi'°° D1et1or <br />RE: Partial Phase II Bond Release, Chimney Rock Mine, #C-81-023 <br />I have completed review of the July 1994 responses to my adequacy <br />review dated February 15, 1994 for the Phase II Bond Release for <br />the Chimney Rock Mine. <br />There was not a map submitted for use during my review. I can only <br />assume that the acreage changes which will result from the proposed <br />field modifications have been correctly portrayed. Other issues <br />identified in my original adequacy review have been satisfactorily <br />addressed. <br />Most areas proposed for Phase II release have been demonstrated to <br />contribute less sediment given the modelling assumptions used. The <br />exception is the AVF area which produces a very small amount of <br />sediment (< 1 ton). I will leave the final call on whether this <br />area can be released to you and your senior. <br />One big reason this modelling successfully demonstrated less <br />contribution of sediment in the reclaimed state is due to the <br />extremely poor condition of the reference area. It is important <br />that the cover data of the reference area is valid and <br />representative of field conditions. Your team vegetation expert <br />can easily verify this. <br />Also, given the erosion which has occurred recently at the site and <br />the changes that are proposed to be made, it is very important that <br />we continue to closely monitor and inspect the site for signs of <br />excessive erosion. Proposed changes, if properly done, should <br />increase the landscape stability and improve vegetative cover. <br />I would recommend Phase II release once proposed field changes are <br />completed and the operator has complied with all permit commitments <br />with regard to drainage control. <br />If you have questions let me know. <br />