VERNON, Vt. (AP) — After pumping out 130,000 gallons of contaminated groundwater, removing 240 cubic feet of tainted soil and spending about $10 million responding to a leak of radioactive tritium, Vermont Yankee officials said Tuesday it will be at least three months before the cleanup is complete.
But they say there's no evidence the isotope made it into drinking water supplies and that samples of water from the neighboring Connecticut River continue to show no detectable tritium levels.
In a meeting held at the plant Tuesday, representatives of the troubled nuclear power plant and corporate parent Entergy Corp. released the results of an in-house analysis performed after the Jan. 7 revelation of the leak of tritium — a carcinogen that's been found at dozens of the nation's nuclear reactors.
It blamed the leak on a design flaw in the 38-year-old plant, left-over insulation from a construction job that prevented contaminated water from being collected properly and a separate pipe added to the plant in 1978 that created a pathway that allowed the water to seep into soil.
The report by Vermont Yankee, which was to be delivered to state regulators later Tuesday, also pointed the finger at the plant's own management for not fully implementing groundwater protection measures recommended by the nuclear industry, which it said might've prevented or identified the tritium leak quicker.
Tritium, which occurs naturally in nature but is also a product of nuclear fission, has been linked to cancer if ingested, inhaled or absorbed through the skin in large amounts.
Its discovery at Vermont Yankee came as plant owners sought permission for a 20-year extension that would allow the 650-megawatt plant to continue operating past 2012, when it's currently scheduled to close.
Following the revelation, Vermont lawmakers — in a vote of no confidence — passed a resolution to block the plant from operating past 2012.
Vermont is the only state in the country with a law giving its legislature a say over a nuclear plant's relicensing.
The tritium leak hasn't been the only recent problem.
Last month, plant officials announced that while cleaning up tritium, they found evidence of a more potent radioactive isotope, strontium-90, in soil near where the leak occurred. Strontium-90 has been linked to cancer and leukemia.
On May 29, they revealed another leak after finding and fixing it. That one, which was vapor and water containing 13 different radioactive substances, was found coming from a pipe in a hole workers dug to find the source of an earlier leak.
On Tuesday, they said:
—The groundwater cleanup project, which involves pumping water from underground to the surface and then filtering and storing it, has reduced tritium concentrations in wells closest to the leak site, but monitoring wells closer to the river appear to be peaking now, said Michael Colomb, Vermont Yankee's site vice president.
—Soil containing cesium, strontium-90, cobalt, zinc and manganese has been excavated and removed, though results from final tests on some of it are still pending that could suggest more excavation is needed.
—To date, 130,000 gallons of tainted water have been pumped out, but 300,000 will ultimately be removed, according to Colomb. He said Vermont Yankee doesn't believe it needs to dig up and replace all of its underground piping, as some have suggested.
William Irwin, chief of radiological health for the Vermont Health Department, said the state is satisfied with Vermont Yankee's follow-through on its remediation plans to date.
For now, contaminated soil has been disposed of and no drinking water has been tainted, he said.
"We're concerned that a lot of things could have been done to prevent this, and we hope that that's not an indicator of the future," he said.
Calling the tritium leak a setback to public trust and confidence in Vermont Yankee, Colomb said the plant and its owners would continue their push for another vote by lawmakers and permission to obtain the 20-year license extension.
"Our plan is to convince the Legislature and the people of Vermont, to regain their trust first and then to show them that this plant is reliable and safe and will continue to be reliable and safe," he said.