systems, proper location of skid trails, and restricting operation to appropriate season and 

 ground conditions. 



All of the proposed timber harvest units and post and rail thinning areas have been reviewed 

 and evaluated in the field by a DNRC hydrologist and soil scientist. All wetlands and areas 

 requiring SMZ delineation have also been field reviewed by a DNRC hydrologist to 

 determine their adequacy in meeting the requirements of the Montana Streamside 

 Management Law and in protecting water quality and aquatic resources. 



Comparison of Alternatives 



Alternatives B and C are virtually the same regarding proposed road developments and road 

 improvements. Both alternatives would utilize the existing USPS Road #4325 to access the 

 harvest units proposed in Sections 5, 8 and 17. Both Alternatives B and C would also use an 

 existing BLM road to access the harvest units proposed in 21 and 28. Under both of these 

 alternatives approximately 5.06 miles of new road and .1 miles (Alt B) along with .3 miles 

 (Alt C) of temporary road would be constructed and approximately 2.18 miles of existing 

 road would be reconstructed and improved to a standard that fully complies with BMPs. 

 Another 0.6 miles of existing road would be permanently closed and abandoned under both 

 of these alternatives (see road figures presented in Table 4.2 for a complete breakdown of 

 proposed road work by watershed analysis area). 



Approximately 1 .04 miles of the new road construction planned under both of these 

 alternatives is designed to relocate segments of existing road that contain steep grades, 

 unimproved fords, and located in areas containing high water table and soils with low 

 bearing capacity. Relocation of these segments is expected to reduce erosion and decrease 

 long-term risk of water quality impacts. 



Under Alternative B the new road construction includes a temporary bridge crossing of Bear 

 Creek. Under Alternative C temporary bridges would be installed on both Bear and Beaver 

 Creeks. Both Alternatives B and C include new culvert installations on Huepeck Gulch, 

 Arbuckle Gulch, and the Unnamed Tributaries in Section 17 and Section 21. The temporary 

 bridge crossings of Bear Creek and Beaver Creek would utilize a portable bridge structure 

 designed with a large enough span to accommodate bankfull streamflow and to allow 

 installation and removal to occur without any excavation or disturbance to the stream 

 channel and stream bank. The crossing sites and road approaches to the crossing site will be 

 re-vegetated and stabilized when the bridge structures are removed. No water quality 

 impacts to Bear Creek or Beaver Creek are anticipated from the temporary stream crossing. 



The new culvert installations proposed for, Arbuckle Gulch, Huepeck Gulch and the 

 unnamed tributaries in Section 17and Section 21 are considered low risk for sediment 

 delivery and impacts to downstream water quality in Upper Willow Creek. Some short-term 

 increases in sediment delivery to Huepeck Gulch, Arbuckle Gulch and the unnamed 

 tributaries may occur during and/or shortly after the installation of the new culverts. 

 However, application of BMPs, site-specific design and mitigation measures are expected to 



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