2008-07-18_PERMIT FILE - M2008006

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STATE OF COLORADO DEPARTMENT OF TRANSPORTATION Region Four Materials 3971 W Service Road Evans, Colorado 80645 (970) 350-2379 (Fax) 330-8513 OT DEPARTMFNI'OP TRANSPORTATION Date: April 9, 2008 TO: Erica S. Crosby Environmental Protection Specialist Division of Reclamation, Mining, and Safety 1313 Sherman Street, Rm. 215 Denver, Colo. 80203 From: Gary DeWitt Region Materials Engineer RECEIVED JUL 18 2008 Division or Neciamation, Mining and Safety Re: Connell Resources, Inc. Mining Permit Application for SerFer Pit After reviewing the State permit application for the SerFer Pit, CDOT is submitting the following comments and concerns for your consideration. It states on page six of the application that de-watering trenches will be excavated around the entire perimeter of the disturbed area. Is this the entire 45± acre site, the 30 acre mining site, or the no more that 15 acres that will be disturbed for mining at any one time? Page 11 says the trenches will be constructed around half of the perimeter of the pit. Could we have a clarification on this matter? We assume these trenches be located in the area to be mined and not in the set back areas between the mined area and affected area boundaries. What will be the back slope of these trenches? Steep back slopes left for an extended period of time could cause caving back into the set back areas and reduce their width. On page 6 it states that fines from the settling ponds could be mixed with the overburden and used as back fill. It would be difficult to obtain a uniform homogenous mixture of these fines and the overburden. It would also seem that fines suspended in water would be susceptible to erosion and questionable for use in backfill material for a pond. Page 7 states that inlet and outlet facilities for the reservoir will not be designed at this time. We submit that if a portion the area is to be reclaimed as a water storage facility, the location of the inlet and outlet are of primary concern for this area and this information should be included in the reclamation plan and considered as pertinent as the very specific seeding plan that is required and included in the reclamation plan for re- vegetating the disturbed upland areas. These proposed structures could potentially have an impact on SH 392 and they should be considered during the permitting process and made a part of the Reclamation Permit. Revisions could be requested later if necessary, similar to the process for changes in any reclamation plan. Considering a combined overburden and gravel thickness of 12.5 feet, as stated on page 3, and using the acres of the reservoir and the capacity shown on page 7, there will only be approximately 1.5 feet of bank above the water level of the reservoir. We request that the portion of the reservoir paralleling SH 392, and the NW and NE corners be protected