Two choices for borrow soil are available: It will be necessary to fill a 200,000 yd3 depression, and the fill material must be compacted to 95% of the standard Proctor (maximum) density. A final 10% moisture content is desired in either case.

(a) What is the minimum volume of borrow from each site needed to fill the depression?

(b) What is minimum quantity (volume) of material from each site to haul?

(c) What soil would be cheaper to use?

Borrow B Borrow A 115 pcf Density in place 120 pcf Density in transport 95 pcf 0.92 Void ratio in transport Water content in place 25% 20% $0.20/ya $0.30/ya $0.10/ya $0.40/ya Cost to excavate Cost to haul 2.7 Gs 2.7 112 pcf Maximum Proctor dry density 110 pcf