The Anthropological Studies Center/Sonoma State University is  currently
digging a well in Oakland, California as part of a CRM project. If you
have a machine, excavating out the area around the well--literally
leaving the colum of the well pedestaled--works really well....
CAL-OSHA won't let you dig more than about 4 feet deep without shoring or
excavating around it. Obviously you do need the heavy equipment....
 
Mary Ellin D'Agostino
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