Decision Memo
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DECISION MEMO Portland Post Office Community Club Driveway Relocation August, 2010 USDA Forest Service, Mt. Hood National Forest Zigzag Ranger District Clackamas County, Oregon T3S, R 8E, Section 18, W. M., Clackamas County, Oregon Decision I have decided to authorize the Portland Post Office Community Club (Post Office Club) to construct a new driveway to their cabin on National Forest System lands, located on the Zigzag Ranger District of the Mt. Hood National Forest, at the end of Forest Road 35B, approximately 3 miles southeast of Rhododendron, Oregon. Implementation of this decision may occur immediately. The existing driveway is shared with a neighboring residence on Lot 29, and to access the Post Office Club, vehicles must pass within feet of the cabin. Because the Post Office cabin is a “club” cabin with multiple users who often arrive late at night, conflicts have resulted due to the disturbance of the Lot 29 residents. A new driveway needs to be constructed to access the Post Office Club; located at an adequate distance from Lot 29. Proposed Action The Post Office Club has requested approval to change the access to their cabin at the end of Road 35B by decommissioning a portion of the road they currently use and improving an existing, underused road so that it will replace the current one. The improved road will run 250ft in a generally southwest direction before rejoining the existing access driveway 145 ft to the east of the Post Office Club cabin (see map in Project Folder). This route will have minimum impact on existing vegetation and will not remove any large trees or impact their root systems. The road width will not exceed 9 feet and only one 3” dbh maple will need to be removed. There will be no clearing of vegetation for equipment access entering (see Botany BE). The improved road will follow the current alignment; with one short realignment of about 35 feet between sites 3 and 4. Soil disruption would be limited to this section where a cut and fill will reduce the existing 6 ft. bank. A second short, 3 ft grade drop between location #7 and #8, will be filled with 2”, 1 ½” crushed rock. 1 At the same time the new road is being improved, the old road will be fully decommissioned. This includes de-compaction of the road prism, re-contouring where needed, seeding and mulching of the road bed immediately after road decommissioning is complete, and planting of native trees and understory plants in the fall when conditions permit. Required Design Features and Best Management Practices Fisheries The Post Office Club cabin is located entirely within designated riparian reserves for the Zigzag River and Devils Canyon Creek. And as such, must meet Aquatic Conservation Strategy (ACS) goals of the Northwest Forest Plan and Essential Fish Habitat. It is critical that the long term health and function of the riparian plant community is maintained and/or restored. Thus, the project will include the following mitigation measures to ensure that the long term attainment of ACS objectives is met. I. Fisheries Road Decommissioning Design Features - The following measures are required to be followed for decommissioning the segment of existing driveway that will no longer be utilized. 1. The old driveway will be fully decommissioned from the west side of Road 35B, Lot 29 cabin, to the intersection with the new access road. This includes de-compaction of the road prism, re-contouring where needed, seeding and mulching of the road bed immediately after road decommissioning is complete, and planting of native trees and understory plants in the fall when conditions permit (see Botany Design features). 2. To minimize ground disturbance equipment operators will use the minimum sized equipment necessary to complete the job. This includes using small excavator buckets, hand digging trench lines. 3. User trails and way trails will be decommissioned and planted per the Botany Design Features. 4. No new parking areas will be developed at the cabin and all cars will continue to be parked at the turn around on Road 58. 5. The road will not be widened in the future to provide for access for utility vehicles and care shall be taken to not damage trees or roots along the new driveway. 6. During construction activities a soil and water protection coordinator (from the Zigzag Ranger District) will be assigned with the following duties: Oversee the implementation of the soil and water protection design criteria; Conduct or oversee daily site inspections to ensure effectiveness of soil and water protection design criteria; Oversee the maintenance of structural soil and water protection design criteria; Ensure that any changes to the construction site plans are addressed by coordinating with the Forest Service 2 aquatics staff and insuring that any new soil and water protection design criteria are implemented. 7. II. Fisheries New Driveway Construction Design Features - The following measures are required to be followed during the construction of the new driveway segment. 1. Every effort shall be made to minimize the total impacted area, and associated exposed soils and fill will be piled on level ground away from steep breaks in the terrain to minimize surface flow of silted rainwater run- off into the nearby tributary. Fill produced by all excavation should be evenly distributed on the road surface or removed from the site. 2. If large boulders or downed wood are excavated or moved during the process they should be evenly distributed throughout the disturbed area to achieve a pre-disturbance “natural” look. 3. Certified weed-free mulch will be placed on disturbed ground to mitigate any potential erosion into the surrounding environment. 4. Minimize impacts to existing vegetation; especially large diameter trees and their roots. 5. All equipment working at the site should be in good working order and free of leaks and washed prior to being mobilized to the site to minimize transferring noxious weeds from other work sites. 6. Maintenance and refueling of equipment should occur outside of the Zigzag River and tributary floodplains or any other bodies of water (150 feet or greater from the wetted channel). 7. Erosion control work would be completed prior to any expected precipitation event (as defined by when the National Weather Service, or other accepted source, predicts a 50% or higher chance of measurable precipitation for the local area). 8. Earth disturbing operations would be suspended of there is more than 1.0 inches of rain in 24 hour period at the Log Creek Remote Automated Weather Station (http://www.wrh.noaa.gov/mesowest/getobext.php?wfo=pqr&sid=LGFO3 &num=48&raw=0&banner=off) and/or streamflow in the Bull Run River above the reservoirs exceeds 200 cubic feet per second (http://waterdata.usgs.gov/or/nwis/uv/?site_no=14138850&PARAmeter_cd =00065,00060). Operations would remain suspended until the Bull Run River drops below 200 cubic feet per second and there is less the 1.0 inches of rain in a 24 hour period at the Log Creek Remote Automated Weather Station. III. Fisheries/Aquatics Best Management Practices for Recreation Residence Soil Disturbing Actions 1. The ground disturbance work will only be conducted during dry site conditions in late spring, summer, or early fall. Excavation activities will 3 not take place during saturated soil conditions. Operations will not occur if there is over 0.5 inches of rain in the past 24 hours at the Log Creek Weather Station: (http://www.wrh.noaa.gov/mesowest/getobext.php?wfo=pqr&sid=LGFO3&num=48&raw =0&banner=off). If Log Creek Weather Station is not operational use South Fork Bull Run Weather Station: (http://www.wrh.noaa.gov/mesowest/getobext.php?wfo=pqr&sid=SFBO3&num=48&raw =0&banner=off). 2. Every effort shall be made to minimize the total impacted area, associated exposed soils, and fill will be piled on level ground away from steep breaks in the terrain to minimize surface flow of silted rainwater run-off into nearby water bodies. Fill produced by all excavation should be evenly distributed on ground disturbed by the project. 3. To minimize ground disturbance equipment operators will use the minimum sized equipment necessary to complete the job. This includes using small excavator buckets, hand digging trench lines. Every effort should be made to minimize impacts to existing vegetation; especially trees and their root systems. 4. Oregon State Certified weed-free mulch must be placed on disturbed ground within 48 hours of project completion to mitigate any potential erosion into the surrounding environment. Mulch should completely cover the impacted area and be a minimum depth of 2 – 4 inches. 5. If large boulders or downed wood are excavated or moved during the process they should be evenly distributed throughout the disturbed area to achieve a pre-disturbance “natural” look. 6. Where sediment risks warrant, reduce offsite soil movement through use of redundant filter materials (such as straw bales or silt fencing) if vegetated areas between the site and water bodies if vegetated areas are not present. 7. If specified in the design criteria, impacted areas will be seeded within 2 weeks of project completion with native grass seed from the appropriate seed zone, or annual ryegrass or cereal grain seed (seed must be tested to be free of all Oregon State noxious weeds) at the rate of 150 pounds per acre; and mulched with straw of annual or cereal grain species such as annual ryegrass or wheat from certified weed-free fields at the rate of 4000 pounds per acre. Hydrology 1. The existing driveway between road lot 35B-29 and the intersection of the new driveway will be decommissioned.