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<br />• strength parameters (both angle of internal friction and cohesion) of the Lorencito Canyon <br />Mine generated coal refuse equal or exceed the coal refuse sheaz strength parameters <br />assumed in completing the current existing approved New Elk Mine coal refuse pile <br />stability analysis. Failing this demonstration, the operator would be required to revise the <br />stability analysis to demonstrate compliance with Rule 4.10.4(2); which states "coal mine <br />waste banks shall have a minimum static slope safety factor of 1.5." If appropriate, the <br />specifics of the coal refuse pile design would have to be revised to demonstrate <br />compliance with this requirement. <br />Rule 2.05.4 Reclamation Plan <br />103. On page 2.05-40 of the application, last pazagraph, the first sentence of this paragraph <br />reads; "The reclamation plan will result in the site being returned to appropriate original <br />contour." I am unfamiliaz with the concept of appropriate original contour. I suspect <br />that the author intended this statement to read "approximate original contour" and that <br />this is no more than a typographical error. The regulations exempt the operator from <br />achieving approximate original contour only if the mining qualifies as Mountain Top <br />Removal (Rules 2.06.3 and 4.26) or as Steep Slope Mining (Rules 2.06.4 and 4.27) which <br />qualifies for "limited variance" under Rule 4.27.4. The applicant should provide a <br />discussion demonstrating compliance with one of the above exemptions and state that the <br />1( Lorencito Canyon Mine's surface operations are not required to achieve approximate <br />`.x/p% original contour. <br />Rule 4.14.1(1)(a), "Timing of backfilling and grading... Contour mining", specifies that <br />~,~~'~ "rough backfilling and grading shall follow coal removal by not more than 60 days or <br />1,500 linear feet. The Division may grant additional time for rough backfilling and <br />grading if the pertnittee can demonstrate, through a detailed written analysis under <br />~~ 2.05.4(2)(c), that additional time is necessary." At the bottom of page 2.05-3, the operator <br />requests a variance from the concurrent reclamation requirement of Rule 4.14.1(1)(a); "A <br />~~~ (` ,N/~ vaziance is requested for the first cut through the ridge as it will be Icft open for the <br />XV° second phase of the surface mine which will extend through the southeast portion of the <br />(~ mine azea..." In m y opinion this does not constitute a sufficient "detailed written analysis <br />. _` ~ ,~1\" under 2.05.4(2)(c)" to provide the Division adequate explanation of the request. The <br />~,J` applicant should also provide a detailed map of the temporary configuration of the <br />`~~ variance pit, sufficient to allow calculation of surety to complete reclamation in the event <br />v~t~v` of forfeiture. In addition, the applicant should demonstrate that drainage control can <br />,}' accommodate the temporary configuration and that the requested variance will have no <br />other deleterious impacts upon the environment or the stability of the adjacent reclaimed <br />lands. <br />~~L <br />,~ cls"~" ~~,~ <br />C <br />\V"' <br />J`~ <br />Rule 4.14.2(1)(b) requires the operator to "Backfill and grade to the most moderate slope <br />possible, which does not exceed either the angle of repose or such lesser slope as is <br />necessary to achieve a minimum static safety factor of 1.3." As depicted on Map 2.05.4-1, <br />entitled "Surface Mine Post-Mining Topography", the reclaimed slope of poRions of the <br />backfilled surface mined area appear to exceed the 3:1 (H: V) overall gradient proposed <br />