River) the access roads were less than 0.5 m in depth and subsidence fre- 

 quent I y occurred. 



Access roads to a given site should be limited in number and confined 

 to prepared surfaces. Both season of operation and long-term effects need to 

 be considered in planning. Access to most of the study sites seemed to be 

 appropriate and usually consisted of short gravel ramps and haul roads, 

 sometimes including gravel bars within the river floodplain. 



The practice of constructing temporary gravel ramps, as at the Kuparuk, 

 Sagavanirktok, Ivishak, and Shaviovik Rivers sites to provide access over 

 incised permafrost river banks, reduces bank disturbance (Figure 91). How- 



Figure 91. Gravel ramp at Shaviovik River site providing 

 access over a permafrost river bank. 



ever, cutting into permafrost banks, as was done at the Kavik River, can 

 lead to severe thermal erosion and is not recommended. 



322 



