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<br />there will be no direct discharge from the mine site to surface waters. If this is the case, what is <br />the source of the contaminants to the surface water? <br />Water quality in the mainstem Purgatoire can not legally be decreased past existing <br />stream standards. The proposal (Table 2.05 6-8) states that iron levels may reach 2.4 mg/1 iron. <br />This would exceed current Colorado stream standards for this stream reach. Unless stream <br />standards are changed the company would be fined by the Colorado Water Quality Control <br />Division for any such violation. It seems that the Colorado Water Quality Control Division staff <br />needs to provide comment to this section of the company's proposal. In addition, water quality <br />in Lorencito Canyon can not be lowered to the point a fish kill occurs. The DOW requests <br />additional information pertaining to the adverse effects to the fishery in Lorencito Canyon related <br />to mine development. One specific issue is the introduction of contaminants from disturbed land <br />at the mine site compared to the haul roads up various water courses including Lorencito <br />Canyon. <br />5. Increased sedimentation in Lorencito Canvon and the Purgatoire River It appears that <br />one of the most significant impacts to the fishery of Lorencito Canyon and the Purgatoire River <br />may be increased sedimentation. If sediment increases to a sufficient magnitude both fish habitat <br />and also fish may be completely eliminated. The DOW is concerned about the magnitude of <br />increased sedimentation at the proposed mine site. The DOW is of the opinion that there may be <br />two main sources of sediment to the system, the haul roads (particularly the one passing up <br />through Lorencito Canyon) and the disturbed lands at the site. Surface runoff from both areas <br />may enter the water courses in the area. <br />The applicant plans to contain the runoff from the disturbed lands. The DOW is <br />concerned as [o the degree to which the applicant plans to contain the surface flow from the <br />disturbed lands. At various points in the application reference is made to 5 and 10 year storms <br />events. What is the storm level that will be contained on-site? In the past mines have had to <br />retain surface flow from the 100 year storm event. It is possible to use facilities such as parking <br />lots as flow retention facilities. <br />Surface runoff from the haul roads is also an issue. The ] 2 stream crossings listed on <br />page 2.05-79 of the document indicate that there is more than a slight chance that sedimentation <br />from the proposed haul roads (especially Lorencito Canyon) will be rather significant in <br />magnitude. <br />If sedimentation increases too much fish cold be lost from the lower section of Lorencito <br />Canvon. The flathead chub was most abundant in lower Lorencito Canyon. The DOW would <br />like to assure that land disturbances are minimized in the lower section of Lorencito Canyon. A <br />series of berms and small sediment ponds are probably required along at least a portion of the <br />proposed haul road to reduce the amount of silt entering the stream from road cuts and the <br />roadway. Is it possible to have the company address this issue? <br />It appears that [here may be two haul roads in Lorencito Canyon. One would be <br />constructed by the coal mine. The second would be the existing road used by loggers and other <br />entities. The existing road crosses back and forth across [he stream bed without bridges or <br />culverts. This type of use will gradually result in increased erosion and perhaps loss of fish <br />