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mulch treatment. A third possibility that could be experimented with, is a middle to late <br />summer seeding in an attempt to coincide with the summer monsoon season. However, <br />timing the seeding to coincide smoothly with the mining plan, so that areas are re-graded <br />and topsoiled at the proper times of year to initiate seeding, has not been clearly <br />demonstrated. Amore descriptive mining time-table should assist in developing a plan of <br />how this will be accomplished. <br />Utilizing more than one method should provide plenty of flexibility in maintaining a <br />ground cover over re-topsoiled areas. In the division's opinion, drill seeding is the most <br />effective seeding method, however, broadcast seeding orhydro-mulching are useful on a <br />site specific basis. If broadcast seeding is utilized, the seed rate must be doubled and any <br />areas should be raked or harrowed to enhance seed to soil contact. The use of fabric <br />mulch blankets maybe useful in specific situations, such as steep slopes and highly <br />erosive areas, but is typically not necessazy to establish vegetation over a relatively large <br />and level azea such as the majority of this site. <br />An acceptable seed mix for this azea should be designed to have between 25 and 45 pure <br />live seeds(PLS)/squaze foot for drill seeding and double that for broadcast seeding. The <br />proposed mix has slightly over 100 PLS/square foot, which could work for broadcast <br />seeding but is too high for drill seeding. Also, as mentioned, this mix needs to be more <br />diverse with additional grasses, forbs and shrubs. <br />Another observation of the site was that the shallow drainage bottoms appeazed to <br />contain more western wheatgrass, which is common in native prairie settings. As a result <br />of this, it would seem appropriate to design a separate and specific seed mix to use in the <br />drainage bottoms that would contain a higher percentage of western wheatgrass in an <br />attempt to mimic the natural conditions. There may have also been other grass species <br />that were heavier in these areas and could be increased for this mix as well. <br />With respect to drainages in general, there are a couple of concerns that will require <br />additional information. The post-mining topography basically mimics the original slopes <br />with the exception that it is approximately 30 feet lower in elevation. Drainage ways that <br />existed before disturbance will be re-established in the same general location with <br />approximately the same slope, cross-sectional area, etc. Observations of the existing <br />drainages that will be disturbed during the course of mining were that they were shallow <br />and spread out almost like swales instead of watercourses, especially towazds the bottom <br />before they dropped off into the receiving drainage. The grades were relatively level and <br />exhibited little to no erosion except higher up in the watershed where the drainages were <br />a little narrower and did exhibit some down-cutting and head-cutting. The grades were a <br />little steeper in these azeas as well. When these drainages are re-established, it is likely <br />that erosion will be a concern until the vegetation is well established. Please describe the <br />measures that will be taken to stabilize the drainage bottoms while vegetation is <br />establishing? <br />Another concern is how the undisturbed drainage above the mining azea will be seamed <br />into the reconstructed drainage at the upper end of the mined azea. It would appear that <br />