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the permanent reclamation will be evaluated for three growing seasons (2000, 2001, and <br />2002). <br />The area was mowed during the 1999 growing season (mid - July). Mowing of the cover crop is <br />a normal practice at the Rochelle and North Antelope Mines to reduce competition from the <br />barley stubble with the permanent seed mix. <br />The chosen design alternative was randomized complete block (RCB) and was chosen based <br />on mine limitations with equipment and available area. Within the RCB, one contiguous <br />rectangular area was selected within the reclaimed topography with three distinct replicate <br />blocks. Refer to Figure 2 which also depicts 1998 soil sample locations. Treatment <br />alternatives included: 1) 22 inch "designated permit" replacement depth; 2) 12 inch <br />replacement depth; and 3) 6 inch replacement depth. The treatment blocks were constructed <br />on: 1) a uniform site to control variables other than topsoil depth (e.g., similar slope, aspect, <br />stockpiled topsoil source, and seed mix); and 2) a landscape position that would best represent <br />a pre- and post -mine Breaks Grassland community. Slopes were generally 5:1 and west - <br />facing. The three designated depths were approximate over the treatment replicate and will <br />have minor variation based on weather limitations present during 1998, topsoil source, and <br />equipment utilized for topsoil replacement. <br />Treatment replication dimensions were 175 feet by 250 feet. A 25 foot buffer strip on all sides <br />of the treatment replication was considered to minimize edge effect between replications due to <br />equipment limitations. Therefore, a sample area of 125' x 200' was created within each <br />treatment replication. Corners of treatment replicates were staked with appropriate depth <br />indicators for equipment operators. Both Rochelle and BKS personnel were present during the <br />course of study area construction to visually ensure proper depth placement. <br />Normal backfill suitability sampling of the study site was conducted by Rochelle Mine on 500 <br />foot centers prior to topsoil placement. Refer to Table 1 for analysis. Approximate three -year- <br />old stockpiled material was utilized for this area and was previously removed from former <br />Breaks Grassland topography. Soils within undisturbed Breaks Grassland type consist of <br />shallow entisols on side slopes and hill tops with moderately deep to deep entisols on fans and <br />narrow drainages. <br />Existing Breaks Grassland and Upland Grassland native reference areas will be used to <br />distinguish plant community development and differentiation between treatments. The RCB <br />design was utilized in these native areas as much as possible. Three distinct areas were chosen <br />in each reference area to represent the general slope, aspect and soil depth found in the <br />reclaimed portion of the study. Within these three areas, general replication of the 22, 12, and <br />6 inch blocks were chosen, wherever possible. <br />In order to establish baseline soil fertility status at the reclaimed area treatments and reference <br />areas, a minimum of 2 sample locations were collected within each reclaimed treatment <br />replication. For general comparison purposes only, two samples within each of two native <br />