[Nos.] 11983. 11984, 11985, 12017, 12018, in court of appeals for 9th circuit, no. 11983, Vernon O. Tyler v. S. Birch & Sons Construction Company and Morrison-Knudsen Company, Inc.; no. 11984, William Leslie Kohl v. [same]; no. 11985 Arthur J. Sessing v. [same]; no. 12017, H. A. Lassiter and W. R. Morrison v. Guy F. Atkinson Company; no. 12018, Owen J. McNally v. S. Birch & Sons Construction Company and Morrison-Knudsen Company, Inc., United States, intervener, appeals from district court for western district of Washington, northern division; brief for United States as intervenor.