2010-07-15_REPORT - M1988044 (2)

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The general stream channel in this area has continued to develop a strong growth of cottonwood and willow. This is a major shift in composition from what it was before grazing was removed. At that time the area was dominated by beaten and damaged willows and grossly distorted cottonwoods that had been affected by browsing during the winter months. Now, the cottonwoods are growing rapidly and in some places dominate the willows, but in other places the willows have established an almost impenetrable wall of vegetation in the stream bed. MINING ACTIVITY IN THE LAST YEAR: 1. Depth of mining - In the last year, mining depths were extremely variable due to the spotty and highly variable configuration of the remaining sand. In many instances, mining depth was quite deep, but also very large amounts of overburden and waste (wash fines) were generated. The waste is mostly located near the plant and comes from pond cleanings. Soils were exceptionally deep in some places which generated large volumes of soil for backfilling. Much of this soil is from deeper horizons and therefore of limited value for reclamation uses other than for filling. All mining was in compliance with the depth requirements. 2. Backfilling - Backfilling of mined areas has increased a little in the last year. As described in the plan, mining continues in a deposit until the mining limit is reached or the deposit ends. A. Depth of backfilling - Backfilling that was done exhibited previous patterns of achieving greater depths of fill than would normally be expected. B. Material used in backfilling - Most of the backfilling has used overburden and subsoils stripped from the site where the filling is being done or at least sites that were near enough to the backfilling that it is still considered to be original material. This is consistent with the method of operation described in the plans. Other sources of material include wash fines from processing plant pond cleaning. C. Maximum, minimum, and average slopes - Finished slopes in all the backfilled, graded and topsoiled areas are rarely even close to the 5:1 limit. Most are in the 7:1 to 15:1 or less steep range. The average for backfilled areas in the last year is probably about 7:1 with only a few areas nearly level and steeper slopes being up to 5:1 over small areas. D. Deviation from original elevation for new backfilled land - As described in last year's report, in many areas treated this year, the deviations from the original elevation amounts to only a few feet and when compared to the original topography map it is hard to even determine how much mining was actually done. No actual measurements were taken prior to mining as most of these areas are much older and pre-amendment. Status report for 2009 due July 15, 2010 Page 6 of 11