ProPublica months ago began investigating the scope of the environmental problems caused by the US military on domestic soil. What they found was arresting. The Pentagon has catalogued more than 40,000 contaminated sites across US states and territories, and so far has spent more than $40 billion attempting to clean them up. They’ve found no other single entity — corporation, government agency, or individual — responsible for so much environmental degradation.

Faced with these liabilities, the Pentagon has routinely sought to minimize its responsibility for fixing its environmental problems. It burns hazardous waste and explosives because it's the cheapest way to dispose of them, even though the burning process has been outlawed for most American industries since the 1980s. It employs contractors to dispose of hazardous waste and clean up toxic sites, then claims it is not responsible when some of those contractors commit fraud, improperly handle toxic material, or cut corners on cleanups. In some cases, the Pentagon has explicitly refused to cooperate with the Environmental Protection Agency and let dangerous sites linger unaddressed.

But perhaps nothing better exemplifies the Pentagon's approach to its pollution problem than the story of RDX, one of the world's most powerful conventional explosives. RDX was developed by the US military during World War II. It is now believed by many to cause cancer, and is increasingly turning up in drinking water supplies near military sites across the country. The video above explores how the Pentagon has resisted scientific evidence that RDX causes cancer, even as the human health and environmental dangers of it have surfaced.

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