2009-12-29_REVISION - C1981019 - Laserfiche WebLink

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Bond Release Concerns Relative to Shrub Plots For Phase 2 and Phase 3 bond release purposes, the field trial plots will be included in the vegetation "sampling universe" associated with the bond release block that includes the field trials. Due to the longer period of time associated with development of shrub dominated stands, the occurrence of "bare areas" within the field trial plots will not disqualify a bond release block or portion of the block from Phase 2 bond release. Presence of "bare areas" will be assessed by the Division for Phase 3 bond release, in accordance with the Bond Release Guidelines. Remedial measures determined to be necessary by the Division and the operator due to stand failure within the field trial areas will not reinitiate the bond liability period. Buried Topsoil Test Plots In 2006 under MR-83, Colowyo planned to initiate a buried topsoil protocol to try to increase establishment of shrubs on the mine-site. Two, two-acre test plots were to be topsoiled and then covered with six inches of "benign", nutrient-poor overburden in the attempt to slow or delay emergence and growth by competing grasses and annual weeds, thereby allowing shrub seed additional time to break dormancy and emerge. Prior to seeding taking place one composite soil sample was to be taken from each test plot. The constituents to be analyzed were texture, fertility, pH, percent coarse fragments, electrical conductivity, sodium adsorption ratio, selenium, and boron. To further encourage shrub growth, the seed mix was to be heavily weighted toward shrubs. The seed mixture that was to be used on the test plots is shown below. Seed Mix - Buried Topsoil Test Plot Seed Mix - Colowyo Mine - 2006 ecommen a se s7- Species Synonym Common Name Seeds/lb. lbs. / acre sq. foot Agropyron dasystachyum Elymus lanceolatus ssp. lanceolatus Thickspike Wheatgrass 154,000 0.25 0.8 Agropyron smithil Pascopyrum Smith# Western Wheatgress 110,000 0.25 0.63 Agropyron spicatum Inerme Pseudoroegnena spicata ssp. inerme Beardless Bluebunch Wheatgrass 117,000 0.50 1.34 Agropyron trachycaulum Elymus tradlycaulus ssp. trachyraulus Slender Wheatgress 159,000 0.50 1.83 Poa am la Big Bluegrass 882,000 0.10 2.0 Subtotal = 1.60 6.71 Achillea millifollum Western Yarrow 2,770,000 0.10 6.3 uV Artemisia ludovlciana Louisiana Sagewort 33,600 0.75 0.5 9 Asterchilensis Wgulasterascendens Pacific Aster 2,668,000 0.10 6.1 Unum lewisil Lewis Flax 293,000 0.20 1.35 Artemisla Mdgida Fringed Sage 4,536,000 0.05 5.21 Penstemon strictus Roc Mountain Pensternon 592,000 0.20 2.7 Subtotal = 1.40 22.33 Amelanchieralnifolla Saskatoon Serviceberry 25,800 1.50 0.8 Artemisa tridentata vaseyana Mountain Big Sagebrush 2,500,000 0.25 14.3 „ Artemisla Cana Silver Sagebrush 850,000 0.75 14.63 A triplex canescens Fourwing Saltbush 52,000 1.00 1.1 v Ceratoldeslanata Wiinterfat 56,700 2.00 2.60 m OV),wthamnus nauseosus Rubber Rabbitbrush 400,000 0.50 4.5 Purshia tridentate Bitterbrush 15,000 3.00 1.03 Rosa woodsil Wood's Rose 45,300 1.50 1.5 m once s rotundifolilus Mountain Snowber 75,000 1.50 1 - 2.581 Subtotal = 12.00 43.44 Total 15.00 7248 At the peak of each subsequent growing season, or shortly thereafter, for a period of at least 5 years, these test plots were to be evaluated for emergent shrub density, ground cover by species, and a visual evaluation of surficial erosion. This data would be reported annually in the Annual Reclamation Report. If data shows that there is promise 4.15-11 Revision Date: 12/22/09 Revision No.: TR-84