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ENVIRONMENT, INC. NOVEMBER 6, 201 2 cal and structural engineering analyses that offsite areas will not be adversely affected by blasting. As we discussed preparing the vibration study, geotechnical and structural analysis for a single charge of a 1 / stick of dynamite is unnecessary. You suggested adding a stipulation to address re- quirements to save records, etal. On page 10 starting at paragraph 4 McAtee Construction Co. committed to hiring a registered blasting contractor who would determine the size, type of powder to be used and method to correct the problem. On page 11 paragraph 1 they committed to keeping records at the mine and making them available to the Division upon request. If you feel a stipulation is need to reaffirm these commitments then we will look forward to reviewing the stipulation. 6.4.5 Exhibit E - Reclamation Plan PAGE 3 8. The proposed ponds have fetch distances over 1,000 ft. As such there is the potential that wave action could lead to erosion of the banks of the ponds. Please describe how erosion from wave action will be mitigated or demonstrate to the Division that erosion from wave action will not impact the stability of the pond banks. Possible mitigation measures include armoring the pond banks with riprap. After reviewing the various ideas of protecting the banks for waver action erosion is to place a rip -rap blanket along the areas prone to wave action. We use the term blanket to indicate the riprap will be laid on the face of the slope from 4 feet below the normal water line to 1 foot above and be an average thickness of 12 inches. This will amount to approximately 0.75 cubic yards per linear foot ( 20'x 1'x 1 27ft /yd The native material is sandy so it will not be possible to excavate a trench along the band where the riprap will be place. The excavation would not hold its shape long enough to place the riprap so the riprap blanket will be placed on the surface of the slope. The rip -rap material we proposed to use is recycled broken concrete no less the 12 inches in size, and in may cases it will be much larger pieces of sidewalk, curb & gutter and slabs. The concrete will be aged more than 60 days so it meets the Colorado Department of Healths' definition of Inert Material. We estimate that the areas needing the most protection will be approximately 2/3 of the eastern shore and 2/3 of the southern shore in both lakes. For a total in the Stage I of 1180 feet and Stage II in 1020 feet. For Stage I the rip -rap project will call for approximately 885 cy and for Stage II approximately 775 cy for a total of 1660 cy The area where rip -rap armoring will be placed is shown on the revised copy of the Reclamation Plan maps submitted with this response. Figure AD - is a cross section sketch showing the location of the rip -rap blanket in relation to the water line. McAtee Construction Co. generates this much material every 6 months so as mining approaches the east bank they will begin to stockpile the rip -rap material so there is sufficient broken concrete available on site prior to beginning placement. It will be many years before this is needed. As we begin to accumulate the Rip -rap material McAtee Construction Co. will contact the Division to incense the reclamation bond to cover the cost of placement.