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Proposal to Rremedy Downslope Erosion Below <br /> Portal Benches at Mines 1, 3 and 4 <br /> The steep nature of these slopes combined with the poor growth <br /> characteristics of the Mancos Shale material of which the slopes <br /> are comprised make revegetation extremely difficult. Natural <br /> Mancos Shale slopes exist all around the immediate area and they <br /> have not vegetated in many thousands of years. <br /> Mid-Continent Resources proposes to employ the following <br /> measures to reduce perceived impacts of the downslope areas: <br /> 1) Construct rock and gravel filter berms at the toe of the <br /> downslopes which will not detain runoff water, but will <br /> slow it down so that most sediment will settle behind the <br /> berm. In areas where sufficient rock is not available, <br /> slash timber may be used. If the rock and gravel filters <br /> are installed properly, runoff from the slopes will be <br /> approximately equal in quality to the natural slopes of <br /> the surrounding area. The map sections show the berms at <br /> all three sites although two downslope areas at Mine #1 <br /> cannot be protected in this way. The terrain is too <br /> steep and the toe of the area is inaccessible. These <br /> filter berms can be installed as soon as weather permits. <br /> 2) Immediately after portal bench reclamation, a contour <br /> ditch will be installed at the upper edge of the slopes <br /> to prevent water from travelling down them. This should <br /> aid the revegetation effort. <br /> The above actions represent best management practices and <br /> good-faith efforts to remediate the pre-law downslopes at Mines #1, <br /> 3 and 4. MCR cannot guarantee the success of these actions and no <br /> future work is proposed once the final backfilling and grading of <br /> the portal benches is completed in accordance with the currently <br /> approved reclamation plan. <br />