2008-05-28_REVISION - C1981019 (2)

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passes to facilitate travel in one direction, and then back. In such a manner, seeding equipment could be hooked and unhooked at one end of a reclamation unit without excessive travel. Similarly, field practicalities may dictate that 2, 4, or 6 passes are warranted with given seeding equipment before switching because of complications of attachment or other factors. If seeding equipment exhibits an 8-foot width, then alternating bands would be approximately 16, 32, or 48 feet wide for the example 2, 4, or 6 pass scenario. None of these widths, or even greater widths, would be problematic from an ecological perspective. In addition, such banding would maximize "edge effect" for sage grouse populations. The aforementioned sagebrush steppe limitation to 10% or flatter slopes may be exceeded (up to 15% slope) at the discretion of the reclamation coordinator for given opportunities that may be presented. However, in any such circumstances where the 10% slope limitation is exceeded, the "banding" technique will necessarily become a standard (mandatory) procedure to preclude excessive erosion. Mulching Techniques During the initial permit review process, Colowyo proposed that on slopes flatter than 4h:ly that rather than utilize a hay mulch, a stubble mulch or no mulch be used on reclaimed areas. The use of mulch on these relatively flat slopes was of no value towards reclamation at the Colowyo site. The application of mulch had become a very expensive, time consuming process which, in fact, produced additional problems on the reclaimed areas, rather than solving an assumed erosion problem that can be solved by other methods. The added flexibility of eliminating the use of any mulch greatly enhances the germination of seeds earlier in the spring given the moisture and soil temperature conditions found at the Colowyo site. Mulches tend to shade the soil, thus slowing the rise in soil temperature needed for germination of seeds. At Colowyo, soil moisture is not usually a limiting factor. Soil moisture is usually very high during the spring, due to precipitation during the winter and early spring months. The summer months are generally dry, often with little additional precipitation. By eliminating the use of mulch, the soil temperature is increased earlier in the spring, thus enabling the seeds to germinate earlier when soil moisture conditions are optimum. When the seeds germinate earlier, they are able to utilize soil moisture earlier in the growing season. This results in further root development by the plants, aiding survival through the dry summer months. Only south-facing slopes would benefit from the use of mulch under the moisture conditions at the Colowyo Mine. Without the use of a mulch, erosion control has been maintained with surface manipulation methods such as contour furrows, drainage benches and permanent drainage' channels. The initial reclamation at Colowyo that began in 1978 is indisputable evidence that the methods used at Colowyo have proven highly successful in controlling erosion on slopes as steep as 3h:ly until vegetative cover has established. Where deemed necessary by the reclamation coordinator (e.g., sagebrush steppe targeted areas, south-facing slopes, etc.), techniques such as mulching, chisel plowing, or discing on the contour will be reinstated as necessary. The Division's concerns were previously directed at vegetative establishment on the unmulched areas. The Division's initial permit concerns were expressed in the following 2.05-59 Revision Date: 3/14/08 Revision No.: TR-72