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Greg Lewicki And Associates <br />P9dR 9 ~ <br />11541 Warrington Court Phone: (303)346-5196 Fax(303)-346-6934 <br />Parker, CO USA 80135 E-Mail: lewicki7@atthi.com <br />Steve S.~Shuey _ Mazch 12, 2004 <br />DMG rand Junction Field Office , <br />101 South 3`d Street, Room 301 PI~.f~d. ~ `~ <br />Grand Junction, CO 81501 (~j ~ ~ Z~ / ~vt - (q~~_ paw ~ <br />Dear Mr.Shuey, d '`f~"3 Seco..~- <br />~ ~; .. ~4dtg,~tey~~vlsw R~s~s./ <br />I have addressed the adequacy issues in the attached document. I will also address the issues in <br />the form presented in your Second Adequacy letter dated February 20, 2004. <br />New Area <br />1. Proof of mailing for the requested parties is included. A list of all notifed parties is also <br />included. <br />2. <br />3. <br />4. <br />The name has been revised. <br />All maps have been revised to more accurately reflect on-site conditions. <br />Direction of mining and mining limits both 3H:1 V and O.SH:1 V have been added to the <br />maps. <br />This issue is being addressed in two ways. All existing slopes will be filled as agreed at <br />the on-site meeting. All future steep slopes(O.SH:1 V) will be limited to a 65 foot offset <br />from the permit boundary. This offset is derived from a 20 foot offset for the crest of the <br />3H:1 V slope plus a 45 foot offset. The 45 foot offset serves two purposes. First, the <br />volume of material left in the highwall will allow the crest to be pushed towazds the toe <br />with final slope of 3H:1 V requiring no backfill material. Secondly, this offset provides <br />additional slope safety. It should be noted that the current highwalls with O.SH:1 V slopes <br />demonstrate a greater than 1 safety factor. It is demonstrated through no evidence of <br />slope failure during the life of the pit. However, a failure would be governed by the <br />internal angle of friction of the material. This would limit the failed slope to an angle of <br />38 degrees or ~1.3H:1 V. This failure would not only stay within the permit area, it would <br />stay within the final slope envelope. <br />