1.Soil have a void ratio of 0.68 as it exists in a borrow pit is to be excavated and transported to a fill site where it will be compacted to a void ratio of 0.45. The volume of fill required is 2500 m^3. Find the volume of soil that must be excavated from the borrow pit to furnish the required volume of fill.
2.You purchase a house with a known radon problem. The house has a dirt-floor crawl space (1m high). The emission rate of radon into the crawl space is reported to be 0.6 pCi/m^2-s. An exhaust system was added to provide 1 air exchange per hour (ACH) in the crawl space. The outdoor concentration of radon is 1 pCi/L. Estimate the radon concentration in the crawl spce (in pCi/L).