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lik <br />(M*W, TETRA TECH <br />December 11, 2009 <br />Mr. Jared Ebert <br />Environmental Protection Specialist <br />Division of Reclamation, Mining and Safety <br />Department of Natural Resources <br />1313 Sherman Street, Room 215 <br />Denver, CO 80203 <br />RE: Response to Adequacy Review #2 Comments for Lafarge West, Inc's Greeley <br />35 Avenue Mine, DRMS File # M- 1977 -036, Amendment 01 <br />Dear Jared: <br />This letter is in response to your Adequacy Review #2 Comments for Lafarge West, Inc's <br />Greeley 35 Avenue Mine, DRMS File # M- 1977 -036, Amendment 01. Below is a <br />listing of the comments followed by our responses to those comments. <br />6.4.3 EXHIBIT C — Pre - mining and Mining Plan Map(s) of Affected Lands <br />A. Please address Item #2 from the first adequacy review: <br />2. Also, in order to evaluate the present level of disturbance for the current affected <br />land, please submit a topographic map with contours of sufficient detail to <br />determine the direction and rate of slope for all the current affected land within <br />the permit area. This is necessary in order to evaluate the financial warranty. The <br />division will need to know the angle of the current pit slopes to determine how <br />much earthwork is needed to reclaim the land at the present time. <br />The site was flown on October 7, 2009 to obtain information regarding all of the <br />existing pit slopes; this information is shown on the Pre - mining Plan included with <br />Exhibit C The existing mine perimeter slopes range anywhere from 1.5:1 to 10:1. <br />The interior /bottoms of the individual mine cells are nearly flat but are gently sloped <br />to aid in site dewatering through the use of a series of dewatering trenches. In the <br />plant site area, the topography is also nearly flat with a gentle slope to the North/ <br />Northeast; the exceptions to this are the temporary stockpiles that are in this area <br />B. Please display the current topsoil pile located along 35 Avenue on the Mining Plan <br />map. <br />With the addition of the topographic information, the topsoil pile /berm located along <br />35` Avenue is now shown on the Mining Plan map. As you will see, this pile /berm is <br />both north and south of the site entrance off of 35` Avenue. When the site is <br />reclaimed, the pile /berm to the north of the access will be removed and that topsoil <br />will be used for reclamation. However, we have left the pile /berm that is south of the <br />1900 S. Sunset Street, Suite I -F Longmont, CO 80501 <br />Tel 303.772.S282 Fax 303.772.7039 www.tetratech.com <br />