2002-02-07_REVISION - M1976020 (7)

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year following extraction from the river. Processed material is stored in stockpile areas as shown on Map C-2. Hot bituminous pavement made on site is not stored in the permit area; it is taken directly to the job site. The washed sand and gravel is used primarily to produce concrete for the Durango area. The concrete is batched on site and delivered to the job sites by truck. The haul road from the processing area to the Highway 550 entrance in an existing road approximately 25 feet wide and 700 feet long. This road is not in the permit area and is not planned for reclamation. From the permit amendment in 1995, the permittee has committed to conduct annual stream chan- nel surveys together with a report analyzing the results from year to year. These surveys will show how the river channel is changing annually with respect to depth and horizontal movement. The permittee has also committed to mine no lower than the 6645' elevation in the river. This means that no specific annual production from the site is identified. The site can mine to this level in order to maintain river stability. From year to year, the tonnage mined will vary depending on the spring thaw flows and also major mnoff events which usually occur during the summer and early fall. By extracting no deeper than 6645', the plan ensures that a stable river channel will always be main- tained at its historic grade of approximately 0.734%. No off site effects will be experienced. Future plans include removing the dike berm, which is approximately 25' wide and up to 20' high and over 1300' long which divides the east and west channels of the River. This dike berm was placed in the river years ago at the direction of the Corps of Engineers and discussions are currently underway (in 2002) with the Corps and the CDMG regarding the removal of the dike berm and final filling of the dredge hole in order to further restore the channel to a more natural configuration. This would also improve the nearby hydrology as well as the visual aspects of this stretch of the river. The work would re-establish a wide stable channel at a determined grade and establish a harvest system which would have the least impacts on the channel and the areas around it. Since these plans have not been completely formulated with the parties involved, they are not included in the January 2002 amend- ment to the permit. It is hoped that these plans can be formulated and agreed upon in the summer of 2002. The river gradient for this stretch of the Animas River and the approximate water elevations for var- ious flood events are included as Figure 1 in Appendix C -River Data. This chart was obtained from the US Army Corps of Engineer Flood Hazard maps for the area. It is seen that the 100 year flood produces a water elevation that is approximately 8 feet above the riverbed in the site area. The Thomas Pi[ 2/02 8