Yankee: More radioactive woes
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By Susan Smallheer STAFF WRITER - Published: January 23, 2010
BRATTLEBORO — Entergy Nuclear has hired a Washington, D.C., law firm to assist the company in its internal investigation over whether company officials lied to state regulators last year over the existence of radioactivity in buried pipes, which appear to be the source of increasing levels and types of radioactivity leaking at the Vernon reactor.
The Nuclear Regulatory Commission confirmed Friday that cobalt-60 and zinc-65, which are much more dangerous radioactive isotopes than tritium, have also showed up in dangerous levels in an underground trench where tritium registered up to 2 million picocuries earlier in the week.
Cobalt-60 registered at 13,000 picocuries, while the federal reportable levels are 100 picocuries per liter. For zinc-65, the level was 2,460, while the reportable level is 300 picocuries per liter. For tritium, the level is 20,000 picocuries for drinking water, and 30,000 picocuries in general. The most recent test in the trench for tritium put it at 1.6 million picocuries.
Both Entergy and NRC officials stressed that while the high levels of the radioactive isotopes were found in water in areas where they shouldn't be, they were in a contained, locked, underground building and posed no immediate risk to the public through exposure.
Meanwhile, the state's congressional delegation late Friday reiterated its called for a special investigation of Vermont Yankee by the Nuclear Regulatory Commission, saying that "alarming" information continued to come out of the plant.
"These recent developments coupled with our ongoing concerns about Entergy Vermont Yankee's commitment to safety and forthrightness with the public and regulatory and safety agencies, force us to reiterate our request for an immediate and thorough investigation," stated the letter from Sen. Bernard Sanders, an independent, and Sen. Patrick Leahy and Rep. Peter Welch, both Democrats.
"This immediate and thorough assessment of the full extent of contamination is critical to our meeting that commitment," they added.
Robert Williams, Entergy Nuclear spokesman, said late Friday that the company had brought "outside counsel" on board "to support our comprehensive internal review of the statements" made by Entergy Nuclear officials regarding the existence of the buried pipes.
Williams said he didn't have the name of the firm or where it was from, although Arnie Gundersen, a consultant for the Legislature, said he had been told the firm was from Washington, D.C., and was meeting behind "locked doors" with people involved in the investigation.
"I was informed by the Department of Public Service that VY has hired a D.C. law firm, with attorneys and investigators on site," said Gundersen, a Burlington nuclear engineer, who also served on the Vermont Yankee Oversight Panel.
Entergy is due before the Public Service Board next Wednesday to explain why its top two officials in Vermont, Jay Thayer, vice president for operations, and Michael Columb, site vice president, both told the board under oath last May that there were no buried pipes at Vermont Yankee that contained radionuclides.
Additionally, one of its top engineers, David McElwee, who acted as the chief liaison engineer to the Legislature, also made statements to legislative staff late last summer that no such pipes existed.
Investigating such a piping system was a legislative requirement of Act 189, a special reliability inspection of the reactor, which is seeking state approval to continue operating beyond 2012.
Last week, Thayer apologized and said he had obviously misspoke, and acknowledged that there were several such pipes. The pipes are considered the probable source of the leaking tritium.
Cleaning up radioactive contamination is considered to be a major expense when the reactor is shut down, dismantled and cleaned up.
Neil Sheehan, spokesman for the Nuclear Regulatory Commission, said a special team from the NRC would be in Vermont to work with Entergy on its investigation into the source of the tritium, cobalt-60 and zinc-65.
All three radioactive isotopes are byproducts of the nuclear fission process. Sheehan said the existence of all three in the trench gave investigators additional clues as to the potential source of the leak.
Williams, in an e-mail to reporters, called the cobalt-60 "a trace amount," and said it was located in a building that handles radioactive waste from all over the reactor.
The so-called radwaste trench was discovered to have highly radioactive water in it last week, although state and Entergy officials never released that information. Legislative leaders Sen. Peter Shumlin, the Windham Democrat who is president pro tem of the Senate, and House Speaker Shap Smith released the information Wednesday.
Entergy officials pumped out more than 150 gallons of contaminated water, but a few days later, another 60 gallons had accumulated.
Sheehan said Entergy was looking at the possibility that the water accumulated as a result of condensation.
According to the Department of Health, which has launched a special page on the tritium issue at Vermont Yankee, the trench was tested again, and tested at a rate of 1.6 million picocuries.
That Web site is http:healthvermont.gov/enviro/rad/yankee/tritium.aspx.
Williams said a specialized contractor is preparing to drill additional groundwater monitoring wells around the reactor. Drilling will start Saturday, with the first new well to be ready for testing next week.
Only one of the current three monitoring wells has shown tritium, despite a false positive in the northernmost well. The contaminated well, which is 30 feet from the Connecticut River next to the reactor building, has shown fluctuating levels of tritium, from 14,000 to a high of 28,100 picocuries per liter, to its current test of 20,900 picocuries, just above EPA federal drinking water standards.
susan.smallheer@rutlandherald.com
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