According to US Environmental Protection Agency documents released in late 2002, UXO at 16,000 domestic inactive military ranges within the United States pose an “imminent and substantial” public health risk and could require the largest environmental cleanup ever, at a cost of at least $14 billion. It costs roughly $1,000 to demolish a UXO on site. UXO cleanup in the US involves over 10 million acres (40,000 km2) of land and 1,400 different sites. Some individual ranges cover 500 square miles (1,300 km2), and, taken together, the ranges comprise an area the size of Florida.

According to the EPA’s National Priorities List (NPL) Sites by State the top five states with the largest number of active sites are: California, Washington, Virginia, Maryland, Massachusetts, New Jersey, Alaska, Florida, Pennsylvania, and Illinois.

UXOinfo.com also maintains a list of UXO sites in the US.