Those in favor of mobile nuclear power for the battlefield claim it will provide "unlimited, low-carbon energy" //

The PM-2A was built in 18 months. It arrived at Thule Air Force Base in Greenland in July 1960 and was dragged 138 miles across the ice sheet in pieces and then assembled at Camp Century. //

The Army called the reactor portable, even at 330 tons, because it was built from pieces that each fit in a C-130 cargo plane. It was powering Camp Century, one of the military's most unusual bases.

Camp Century was a series of tunnels built into the Greenland ice sheet and used for both military research and scientific projects. The military boasted that the nuclear reactor there, known as the PM-2A, needed just 44 pounds of uranium to replace a million or more gallons of diesel fuel. Heat from the reactor ran lights and equipment and allowed the 200 or so men at the camp as many hot showers as they wanted in that brutally cold environment. //

The PM-2A ran for two years, making fossil fuel-free power and heat and far more neutrons than was safe.

Those stray neutrons caused trouble. Steel pipes and the reactor vessel grew increasingly radioactive over time, as did traces of sodium in the snow. Cooling water leaking from the reactor contained dozens of radioactive isotopes potentially exposing personnel to radiation and leaving a legacy in the ice. //

When the reactor was dismantled for shipping, its metal pipes shed radioactive dust. Bulldozed snow that was once bathed in neutrons from the reactor released radioactive flakes of ice. //

The U.S. military's first attempts at land-based portable nuclear reactors didn't work out well in terms of environmental contamination, cost, human health and international relations. That history is worth remembering as the military considers new mobile reactors.