With temperatures rising across the globe, the poles are being hit particularly hard. Melting Arctic sea ice could wreak plenty of havoc through rising sea levels, but other potential hazards are coming to light. If these warming trends continue, a US military base, built into the Greenland Ice Sheet and abandoned since the 1960s, could eventually be freed from the ice – along with hundreds of thousands of liters of waste and pollutants.

A "city under the ice," Camp Century was built in Greenland in 1959 encased within the ice sheet. Officially, it was there for scientific research and to experiment with construction techniques under those extreme conditions. Unofficially, it was intended to develop into a nuclear missile launch site within reach of the Soviet Union. While that never eventuated, the facility did house up to 200 people and was powered by a nuclear reactor.

When the camp was decommissioned in 1967, everybody essentially just up and left, on the assumption that the ice would entomb the facility and seal the harmful materials within. And to an extent it has, with snowfall piling a further 35 m (115 ft) of ice on top of the camp in the years since.

Camp Century was built into the Greenland Ice Sheet during the Cold War, and abandoned in 1967, leaving behind hundreds of thousands of liters of pollutants US Army

But in a new study led by William Colgan, a climate scientist at York University in Toronto, researchers looked at climate projections and found that by the end of the century, the ice might be melting faster than it's being replenished.

"When we looked at the climate simulations, they suggested that rather than perpetual snowfall, it seems that as early as 2090, the site could transition from net snowfall to net melt," says Colgan. "Once the site transitions from net snowfall to net melt, it's only a matter of time before the wastes melt out; it becomes irreversible."

The wastes in question pose a significant hazard. Thankfully, the nuclear reaction chamber was removed when the camp was abandoned, but the infrastructure is still there, which, according to the researchers' studies of Arctic building materials of the time, could contain toxic polychlorinated biphenyls (PCBs). That's on top of an estimated 200,000 liters (53,000 gal) of diesel fuel, and 240,000 liters (63,400 gal) of waste water, including sewage and radioactive coolant from the generator. Melting ice could carry these pollutants to the ocean, putting marine ecosystems at risk.

So what can be done about it? For now, not much, according to the study. Considering its depth, an attempted cleanup would be costly and difficult. "It really becomes a situation of waiting until the ice sheet has melted down to almost expose the wastes before anyone should advocate for site remediation," says Colgan.

When that time comes, the question of who is responsible for the effort is a politically sensitive one. Being a US base built on Danish land, but within the now-self-governing territory of Greenland, international law is a little unclear about the responsibilities for existing hazardous waste.

"The study identifies a big hole in the extant set of laws and rules we have to deal with environmental problems globally," comments Jessica Green, a political scientist at New York University.

The research was published in the journal Geophysical Research Letters.

Source: University of Colorado, Boulder