It recommends collecting DU fragments, covering contaminated points with asphalt or clean soil, and keeping records of contaminated sites.

BBC: UK to aid Iraq DU removal

Nevertheless, as the soil, asphalt and concrete is removed overall radiation levels should fall.

BBC: Daunting challenge of Fukushima clean-up

"When you replace soil and grass with concrete and asphalt, you alter the balance of energy that occurs at the earth's surface, " says Dr. Robert Bornstein, a professor of meteorology at San Jose State University in California.

CNN: In-Depth Specials - City Limits