SITE SELECTION AND INVESTIGATION 



Selection of a gravel removal site often begins with a comparison 

 of candidate floodplain and/or upland sites in the immediate use area. 

 Upland sites are beyond the scope of this report and will not be further 

 considered. The site selection process includes preliminary selection, site 

 investigation, final selection, and mining plan preparation. 



PRELIMINARY SITE SELECTION 



Preliminary selection of one or more candidate sites results from 

 assembling and reviewing available information followed by implementation 

 of an appropriate selection procedure. 



Sources of Information 



Primary sources of information used in preliminary site selection 

 are topographic maps, sur f i c i a I geologic maps, and aerial photographs. 



Topographic maps of 1:250,000 and 1:63,360 scale are available from the 

 U.S. Geological Survey (USGS). Similar topographic maps are also available 

 for Canadian arctic and subarctic regions. From these maps, one can obtain 

 a general impression of the size and type of river, potential gravel availa- 

 bility, desirable access routes, and proximity to the use area. 



The only currently available surficial geologic map of Alaska is the 

 1964 USGS map entitled "Surficial Geology of Alaska". With a scale of 

 1:1,584,000, this map does not show much detail. However, USGS recently 

 published a potentially useful set of maps which cover the Trans-Alaska 

 Pipeline route from'Prudhoe Bay to Valdez. 



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