NEW YORK (Reuters) - Entergy Corp said on Thursday it found and stopped the source of a radioactive tritium leak at its Vermont Yankee nuclear power plant and has begun initial work to support the remediation of soil and groundwater.
Since identifying the leak in January, Entergy has said there have been no detectable tritium levels found in any drinking water well samples at the Vermont Yankee site or in the Connecticut River.
The 620-megawatt plant is located near the Connecticut River in Vernon in Windham County about 140 miles west-northwest of Boston.
Tritium is a mildly radioactive isotope of hydrogen that occurs naturally in very small amounts in ground water. It is also a byproduct of power production in nuclear plants.
Vermont Yankee engineers said the leak came from two separate pipes inside a concrete tunnel.
A floor drain that normally would have taken the water from the tunnel for normal processing was found to be clogged with debris and mud, allowing water with tritium to seep through an unsealed joint in the tunnel wall to the soil and eventually the groundwater.
The company has rerouted the pipes, which drain moisture from the plant"s Advanced Off Gas (AOG) system.
Entergy said it started remediation to remove the tritium with the pumping of shallow groundwater into above-ground containers for processing and reuse in the plant.
The pumping will reduce the concentration of tritium in the groundwater. The company also plans to remove about 150 cubic feet of soil that contains small amounts of other contaminants such as manganese and cobalt. Entergy said it will dispose of the soil at a federally licensed disposal facility.
TRITIUM AND LICENSE RENEWAL
In February, the Vermont Senate voted overwhelmingly to shut the reactor in 2012 when its license expires due in part to the tritium leak and anger over comments about underground pipes at the plant that some thought were misleading.
Entergy reprimanded several plant managers for making allegedly misleading comments that there were no underground pipes at the plant.
The company said plant managers meant there were no underground pipes touching dirt as opposed to underground pipes contained in concrete like the pipe the leak came from.
The Senate also voiced concerns over future power prices and worries about Entergy"s plan to spin off its nonregulated nuclear reactors, including Vermont Yankee, to a separate company to be called Enexus.
Entergy, however, has said it would keep working with state officials and the U.S. Nuclear Regulatory Commission in an effort to win a 20-year renewal of Vermont Yankee"s operating license.
The NRC is reviewing Entergy"s 2006 application to renew the plant"s 40-year operating license for another 20 years.
(Reporting by Scott DiSavino; editing by Jim Marshall)
No comments:
Post a Comment