reduce erosion and potential sediment delivery to an acceptable level as defined under the 

 Montana Water Quality Standards. Acceptable levels are defined as those conditions 

 occurring where all reasonable land, soil, and water conservation practices have been 

 applied. 



The new culvert planned for Arbuckle is intended to replace an existing unimproved stream 

 crossing. This installation is designed to reduce existing erosion and water quality impacts 

 occurring at this site. No downstream delivery of sediment to Upper Willow Creek is 

 anticipated. These other crossing sites are ephemeral or intermittent, and discontinuous with 

 no direct delivery to down slope streams supporting cold-water fisheries or other sensitive 

 beneficial uses. 



Alternative D is also similar in regards to the road construction and road improvements 

 proposed. Under this alternative the road layout is designed to circumvent old growth 

 stands. This alternative proposes building 4.38 miles of new roads, 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 this alternative. 



The road construction proposed under this alternative also includes 1 .04 miles of new road 

 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. 



The new road construction planned under Alternative D also includes temporary bridge 

 crossings of Bear Creek and Beaver Creek, and new culvert installations on Huepeck Gulch, 

 Arbuckle Gulch, and the unnamed Tributaries in Section 17and Section 21. 



The temporary bridge crossings of Bear Creek and Beaver Creek would utilize portable 

 bridge structures with similar designs with identical risk as those described under 

 Alternative C. 



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

 Unnamed Tributaries in Section 17 and Section 21 are considered low risk to impact 

 downstream water quality and beneficial uses as described under Alternatives B and C. 



Timber sale harvest unit locations and acreage are similar under all three of the proposed 

 action alternatives. The only differences between the action alternatives regarding timber 

 harvest are the extent and location of proposed post and rail thinning, and the exclusion of 

 old growth harvesting in Alternative D. No impacts to water quality or downstream 

 beneficial uses are expected to result from the harvest activities proposed under any of the 

 action alternatives. Streamside management zones and equipment restriction zones will be 

 designed to effectively buffer streams and other ephemeral drainage features from harvest 

 activities. No SMZ harvests are proposed under any of the action alternatives. 



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