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<br />iii iiiiiiiiiiiiiiii <br />STATE OF COLORADO <br />DIVISION OF MINERALS AND GEOLOGY <br />DeWnmem of Natural Resources <br />131 3 Sherman St .Room ?15 <br />Denver, Colorado 80?03 <br />Phone: (3031 866-3567 <br />FA:(. (3071 812-8106 <br />December 22, 2000 <br />DIVISION OF <br />MINERALS <br />GEOLOGY <br />RECLAMATION <br />MI NIN G•SAFETY <br />Owen Leonard Bill O.. ens <br />Governor <br />CDOT Regional Director <br />in Greg E. Walther <br />222 South 6 Street, Room 308 E.ecueve Dueuor <br />Grand Junction, CO 81501 micn,el e. Long <br />Drvrsion Dueaar <br />RE: Roadside Portals (Pet~rlit No. C-1981-041) <br />Technical Revision Application 33 (TR-33), and Technical Revision Application 35 (TR-35) <br />Dear Mr. Leonard: <br />I recently spoke on the phone with Rich Perske of your office, regarding the two referenced permitting <br />actions submitted by Powderhom Coal Company (PCC) for their Roadside Portals Mine. Your office was <br />contacted, due to the fact that certain mine facilities affected by the revisions are located adjacent to I-70, <br />within rights of way CDOT granted to PCC. We are interested in any specific concerns or recommendations <br />you may have in regard to these permitting actions, and I have summarized each revision application below. <br />TR-33 <br />TR-33 application addresses concerns raised by the Division of Minerals and Geology (DMG) regarding <br />permanent minewa[er discharge site 002. The revision application was deemed complete by DMG on July <br />12, 2000, and the action is still under review. Currently, approximately 200 gpm of minewater. is discharged <br />at Outfall 002 via two, 4" siphon pipes which exit the mine through the sealed Northwest Intake Portal, <br />located on the highway cutslope several hundred feet northeast of the point where the Cameo on-ramp <br />merges with eastbound I-70. These pipes feed into a 6" pipe, which is routed through a CDOT culvert <br />beneath I-70, [o the outfall location adjacent to the river. DMG had identified concerns with the siphon <br />system as a permanent, postmine feature, due to the fact that the siphon requires continuing and perpetual <br />monitoring and maintenance. Should the siphon cease to function, water levels would rise, likely resulting in <br />uncontrolled discharge through the sealed Northwest Intake Portal. <br />The plan now proposed by [he operator in [he most recently amended TR-33 application submittal, would <br />entail installaton of a gravity Flow dewatering pipe fed by an angled drill hole into the mine workings, <br />located within the "North Decline" reclaimed mine facility area. The proposed 6" to 7" diameter pipe would <br />need to be routed through an existing DOT culvert beneath I-70, to outlet to the river. Narrative and <br />Diagrams associated with the proposal are enclosed. A copy of the adequacy review letter issued by the <br />Division to PCC is also enclosed. <br />TR-35 <br />TR-35 application was submitted in response to a mid-term permit review conducted by DMG. The revision <br />application was deemed complete on December 6, 2000. Under the current reclamation plan for the <br />Roadside Mine South Portal Facilities Area, surface drainage from the site following reclamation would be <br />conveyed beneath the I-70 Cameo overpass, via the 9.5' diameter CMP conveyor tube. Due to engineering <br />