Burlington Free Press
http://www.burlingtonfreepress.com/article/20100120/NEWS02/100120043/High-levels-of-radioactive-material-found-state-to-begin-independent-testingVermont state officials say more radioactive tritium has been found at the Vermont Yankee nuclear plant — at much higher levels than were found in a test well nearly two weeks ago.
William Irwin, the state’s radiological health chief, says
readings of 1 million to 2 million picocuries per liter of the isotope were found in a concrete trench several hundred feet from the test well where tritium was reported on Jan. 7.
Meanwhile, state officials are calling for the state Health Department to conduct its own investigation and not rely on information from Vermont Yankee.
Vermont Yankee nuclear plant officials acknowledged today the company had misstated the test results released a day earlier and that, on further examination, the level of radioactive tritium in a sample taken from a second monitoring was not elevated.
On Tuesday, the company said the sample showed a tritium concentration of 9,450 picocuries per liter what was identified as the north monitoring well. A review of how the test was conducted determined the true amount was negligible.
Tritium is a hydrogen isotope that can be a radiation hazard when it is inhaled or ingested through food or water.
The federal safety standard for tritium in drinking water is 20,000 picocuries per liter.Irwin said the revised test result disclosed by Vermont Yankee nuclear plant was both good news and bad news.
“It reduces one concern but it replaces it with another concern,” Irwin said. “We’re concerned that the initial test result may be indicative of a lack of appropriate quality control in the sample analysis.”
Irwin said it appeared that a container used by Vermont Yankee during its analysis of the sample had a chemical residue inside of it that skewed the results. The correct, lower finding was determined when plant workers re-ran the test using a clean container.
Irwin said that as a result of Vermont Yankee’s testing mistake, his office plans to intensify its own testing program and independently analyze samples from all three plant monitoring wells, plus some 30 other potable and non-potable water wells in the vicinity of the plant.
The testing is being down to identify the source, location and size and seriousness of the tritium plume. Vermont Yankee has agreed to dig 11 more monitoring wells around the plant over the next few weeks to aid in that effort, Irwin said.
Last week, a monitoring well between the plant and the Connecticut River showed tritium levels of around 17,000 picocuries per liter. Tuesday, the company reported that the tritium concentration had grown to 22,300 picocuries per liter over the past two weeks.
The tritium groundwater contamination problem at Vermont Yankee was first disclosed two weeks ago. Last week, the plant came under fire for denying that underground pipes carrying tritium existed at the facility.