The proving ground is contaminated with unexploded ordnance as well as limited and localized amounts of depleted uranium, making it unsuitable for residential or commercial development. Testing ended several months ago at two of the sites, located in New York s Adirondack mountains and the Shenandoah mountains of Virginia. A site in Tennessee s Great Smoky Mountains is still operating with funding from the National Park Service, the EPA s regional office and the Tennessee Valley Authority, the nation s only federally owned utility. But recent reports by environmental groups and the federal General Accounting Office show that acid rain is still a problem in many areas. Acid rain is caused when sulfur dioxide, produced by coal burning power plants and other man made sources, mixes with water vapor in the atmosphere to form sulfuric acid.
Nitrogen gases can also combine with water vapor to form acidic nitrate solutions.
About 200 sites in the U.S. test groundwater for levels of nitrogen and sulfur. Supporters of cloud and fog testing say monitoring of high mountain sites that are often shrouded in mist is needed to maintain a comprehensive record of atmospheric acid levels. In March, the General Accounting Office reported that although sulfur levels have been significantly reduced in high mountain lakes and streams, nitrogen levels have risen in almost half of these water bodies. The U.S. Army has found a way to recycle M60 and M61 training rockets, as well as M67 rocket motors and M441 shipping and firing tubes, as part of the Army's Chemical Weapons Demilitarization Program. None of the components contain chemical warfare agents.