rv. Environmental Effects 

 A. Introduction 



This final chapter of the Gladstone Creek EA will describe the 

 probable effects to those various aspects of the affected 

 environment which were described in Chapter III. 



HYdroloav. Fisheries & Soils 



The Department policy is to fully implement BMP's and to comply 

 above and beyond the requirements of the SMZ law. Implementation of 

 these conservation practices would protect the streams from 

 sedimentation. Specific road surface drainage repairs and 

 installation of a bridge or culvert at an existing ford, in Section 

 27 would improve the existing situation. The 2.S - 4.5 miles of 

 proposed new road construction would have minimal hydrologic impacts 

 due to the proposed locations, the low soil erodibility and the 

 ephemeral nature of the drainages at the road locations. 



The proposed harvest treatments would increase the ECA by 10% in 

 Gladstone Creek and 1.8% in French Creek. Based on stream modeling, 

 we would expect these changes to increase water yield in Gladstone 

 Creek by 1% and in French Creek by 0.2%. These changes are well 

 below levels normally associated with detrimental water yield 

 increases (typically greater than 10%) and channel impacts. 



No long term impacts to downstream water quality or beneficial uses 

 are expected to result from the proposed actions. The full report 

 by the Department Hydrologist can be found in the appendix. 



Soil erosion and displacement on the harvest areas would be 

 minimized if operations were restricted to dry, frozen or snow 

 covered periods. Tractor skidding would be limited to slopes 

 generally less than 45% on Mocmont/Tolex soils and to generally 40% 

 or less on Trapps-Warnecke soils, to further prevent displacement. 

 Ground lead or cable yarding could be used on steeper areas. 



In some areas designated or preplanned trails would be used, along 

 with localized equipment restriction zones to protect micro sites 

 within the harvest areas. A partial tree length system would 

 minimize the number of equipment passes over the land, reducing the 

 potential for displacement or excess scarification. In general, 

 scarification would be limited to 30-40% of the harvest areas, or 

 less. Where possible, 10-15 tons per acre of woody debris would be 

 maintained on site for nutrient cycling to aid long term 

 productivity. 



Adverse soil impacts are not expected given the locations of the 

 proposed harvest units and roads, if BMP's and the specific 

 mitigations described above are implemented. 



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