It was August 2008 near Taji, Iraq. They had just exploded a stack of old Iraqi artillery shells buried beside a murky lake. The blast, part of an effort to destroy munitions that could be used in makeshift bombs, uncovered more shells.
Two technicians assigned to dispose of munitions stepped into the hole. Lake water seeped in. One of them, Specialist Andrew T. Goldman, noticed a pungent odor, something, he said, he had never smelled before.
He lifted a shell. Oily paste oozed from a crack. That doesnt look like pond water, said his team leader, Staff Sgt. Eric J. Duling.
The specialist swabbed the shell with chemical detection paper. It turned red indicating sulfur mustard, the chemical warfare agent designed to burn a victims airway, skin and eyes.
All three men recall an awkward pause. Then Sergeant Duling gave an order: Get the hell out.