Washington state's Hanford Nuclear Reservation is one of the most contaminated places in the United States, with the government recently disclosing that six large underground tanks are leaking up to 2,000 litres of radioactive liquid per year.

The news has alarmed environmentalists, who fear the radioactive material could pass through groundwater to the nearby Columbia River.

Al Jazeera's Rob Reynolds reports from Hanford, Washington.

Source: Al Jazeera