Radioactive tritium used in everything from wristwatches to hydrogen bombs has leaked into groundwater at Virginia's two commercial nuclear power plants during the past four years.
While not known to have reached public water supplies, the leaks are part of a growing trend as the nation's nuclear reactors age, according to an Associated Press investigation.
The AP found that tritium, a form of hydrogen the
Leaks from at least 37 of those facilities, including
The Surry plant and North Anna Power Station in
Tritium, which occurs naturally, is also a byproduct of electricity produced at nuclear plants. It can escape from corroding, buried pipes, as well as tanks and vaults, that carry and store water used to cool reactors.
Dominion reported abnormally high concentrations of tritium at Surry, an 840-acre site located across the James River from
Dominion sampled water that showed a tritium level of 31,900 picocuries per liter. The U.S. Environmental Protection Agency's threshold for safe drinking water is 20,000 picocuries.
While relatively weak compared to other radioactive elements, the EPA found that among people who drink tritium-laced water for decades, there is a seven in 200,000 chance they would develop cancer.
As of December, the tritium concentration at Surry was 14,100 picocuries, according to commission data. Dominion spokesman Rick ZuercherÖ said the isotope naturally dissipated within the plant grounds.
"There was no indication it migrated off the Surry site undetected," he said.
Roughly 450 gallons of water containing 48,000 picocuries of tritium spilled from a Surry storage tank in 2009, Zuercher said. The water and isotope were contained onsite, he said.
Dominion reported a leak at North Anna, about 45 miles northwest of Richmond, last November. One of eight monitoring wells showed a tritium level of 16,500 picocuries.
Ken ClarkÖ, a commission spokesman based in Atlanta, said the well returned to normal levels — 3,000 to 4,000 picocuries — without action from Dominion.
"It certainly didn't present a danger to public health and safety," he said.
Thick concrete walls — similar to those found at nuclear power plants — prevent the release of unsafe radiation, she said.
"We've never seen it (tritium) in our monitoring wells," Dixon said.
The AP investigation comes after the commission, during the last 10 years, approved license extensions for more than half of the nation's commercial nuclear reactors, including the four at Surry and North Anna.
The reactors, which were scheduled to close this decade, were given 20 additional years to operate.
Critics argue the aging plants should be closed. They say private investors are unwilling to bankroll the building of new nuclear plants without significant financial contributions from the federal government.
Meanwhile, the commercial industry continues to suffer backlash from Japan, where a
in March triggered the world’s worst