Specifications. 2997. Earthwork, asphaltic membrane lining, pipe lines, and structures, area W-4, laterals and sublaterals and main drains 045, station 565+00 to S58+55, G45 W, station 0 to 338+35, and 645 WN, station 0 to 80+00, West Canal laterals and main drains, Columbia Basin project, Wash.