The primary purpose of this report is to present cost data associated with the recent construction of biological shields at Hanford. These data are useful for analyzing shields which have been built during the past four years and for ascertaining ways to improve future designs. Specifically, the objectives of this study are to: compile and analyze cost data associated with the construction of the high density concrete shields at 105-K and the steel-masonite shields at 105-C; and determine unit costs for erecting steel forms at Hanford and for filling them with high density concrete.