2004-10-29_GENERAL DOCUMENTS - C1981017 (2)

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Construction Summary The pre-bid meeting was attended by 9 companies. However, only one company bid the Project. The bid exceeded finances available, therefore, DNR purchasing consented to allow the Division to negotiate with the bidder in order to obtain a price that fell within the budget. Negotiations ensued, and a final construction price of$234,734.00 was agreed upon. Bitterroot Restoration sent a crew of eight people to the site, and hand work began on about September 29, 2004. The crews used hand tools to construct benches or shelves on the slopes below the designated mine benches. Approximately 3,500 10"x 6"x 4" benches or shelves were constructed per acre on each mine bench outslope. Bands of trees were planted at each slope as an aid to holding the ground surface in-place. Tree bands were planted at Mines 1 east, 3 upper and lower, and 5. Trees were not planted at Mine 1 west. Trees within the bands were planted on a 4' spacing, horizontally and vertically, with rows being off-set by two feet laterally. A total of 3,000 trees were planted on the outslopes. Shrubs were planted near the toe of each outslope. The purpose of the shrubs is to form organic barriers to sediment migration. The theory is that as the shrubs mature, they will act to disrupt surface flows and retard water velocities, so that sediment is deposited in place. Approximately 4,000 shrubs were planted on the site. In order to promote dispersal of surface water flows form the mine benches, to prevent water from concentrating into gully forming point flows, straw wattles were placed at the crest of each mine bench outslope. There were placed so that they were anchored perpendicular to the fall of the slope at each location in order to most actively disrupt surface water flow. A total of 2,000 lineal feet of wattles were installed. Mine 1 east and west, and Mine 5 were seeded and fertilized from the air utilizing a Llama helicopter flown by Geo-Seis Helicopters, and provided by project subcontractor Western States Reclamation. Due to high winds, Mine 3 upper and lower was seeded by hand. The Division provided the seed, a mixture formulated for the slopes, and containing a quick growing sterile wheat. BioSol fertilizer was applied from the air at a rate of 1,200 pounds per acre. The mulch, a certified weed free slender wheatgrass straw was applied from the air at a rate of 2,000 pounds per acre. Observation indicates that the seed and fertilizer applications were uniform across the slopes. This was fairly easily accomplished as the helicopter distributed the materials via a rotating disc that scattered the materials over a broad area. Multiple passes helped to ensure a thorough coverage. The mulch application was less uniform, as the material was released from a net suspended under the helicopter. Coverage was variable load by load depending on how each bale separated in the air, and on the air speed of the helicopter during the drop. In some instances, hand spreading of the mulch was accomplished due to heavy applications ion some areas, and inadequate coverage in adjacent areas. However, the hand spreading was kept to t a minimum as additional foot traffic on the slopes causes the seed to be lost as soil cascades down the slope. Following application of other materials, a guar-based tackifier was aerially applied to the slopes, over the mulch. Observation indicates that a fairly uniform application of tackifier was achieved at each site.