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Logan Wash Mine TR No. 4 <br />3.0 Mine Benches and Roads <br />3.1 Mine Benches (Area 2, Area 3, and Area 4) <br />The mine bench areas include Areas 2, 3, and 4 as shown on Exhibit F (Attachment A). Area 2 <br />is the Upper Bench, Area 3 is the Lower Bench, and Area 4 is the bench associated with the <br />Research Mine. These areas include the bench production/staging area as well as aJl other <br />flatter-grade ground above the waste-rock dump slopes, The original Plan called for 18 inches of <br />topsoil to be placed on the benches. The existing area of the Upper Bench is approximately 2.3 <br />acres, including the moderately sloped area below the Daylight Portal. The existing area of the <br />Lower Bench is approximately 5.5 acres. Area 4, the Research Mine bench, is an area of <br />approximately 0.8 acres not including the mine access road over the bench (see Section 3.2). <br />Proposed Reclamation <br />The surface materials that make-up the mine bench consist mostly of waste-rock. However, the <br />waste-rock on the benches does contain a sufficient component offine-grained soil-like material. <br />Therefore, OOSI proposes to plant seed mix directly on the scarified bench surfaces without the <br />use of topsoil amendments. The following observations support this approach. <br />Since Logan Wash Mine ceased operations in 1991, the bench and access road areas have <br />developed significant natural vegetation. Species that are currently established on the <br />bench include Rabbitbrush (Chrysothamnus nauseous), Gray Aster (Eurybia glauca), <br />Crispleaf Buckwheat (Eriogottum corymbosum), Stickleaf (Mentzelia argillosa), and <br />several other species. <br />During the summer of 2003, OOSI constructed a simple revegetation test plot on the <br />bench. No top soil amendments were used in the test plot. The plot was scarified and <br />planted with a native seed mix of grass and forbs. Straw was crimped into the rocky soil <br />surface. Because the plot was constructed in the middle of the summer, during the <br />warmest weather conditions, the plot was periodically irrigated. Within two months, the <br />plot showed development of the planted species. <br />Construction of terraces on the Lower Dump and other excavation work (trenching <br />during pipe installation and barrowing for adit plug material) on the Lower Bench <br />revealed that a signiftcant fine component of material exists in the waste-rock that makes <br />up the bench. <br />• Natural (undisturbed) slopes adjacent to the waste-rock areas have relatively poor soil <br />development. Soils are thin and rocky yet still support a variety of vegetation types. <br />OOSI proposes the following revegetation procedures for the mine bench areas: <br />1. Recontour areas that exhibit small sharp topographic features and blend bench into brow <br />of mine dump slope and toe of upslope areas. <br />Western Water & Land, Inc. ~ 5 <br />