Vermont Yankee is seen here from the Hinsdale, N.H., side of the Conneticut river. Zachary P. Stephens/Reformer
Saturday October 9, 2010 BRATTLEBORO -- A sample taken from a former drinking-water well at Vermont Yankee Nuclear Power Plant was contaminated with tritium, according to the Vermont Department of Health.
While no tritium was detected at the deepest range of the well, 360 feet, a single sample, collected on Oct. 2 from the 200 and 220 foot range indicated a tritium concentration of 1,380 picocuries-per-liter, a spokesman for the Nuclear Regulatory Commission said.

The Construction Office Building well goes down about 360 feet and penetrates a bedrock aquifer and is much deeper than the groundwater monitoring wells on site.
"While this single data point indicates a detectable amount of tritium in the Construction Office Building well, it's insufficient information on which to draw any conclusion as to the impact of the tritiated groundwater plume on the bedrock aquifer," Neil Sheehan, spokesman for the Nuclear Regulatory Commission said. "Clearly more work is necessary to determine the significance of the sample.
Entergy, which owns and operates the Vermont Yankee Nuclear Power Plant, received test results Friday afternoon that the water contained 1,040 picocuries-per-liter of tritium and sent notifications to the Nuclear Regulatory Commission and the State of Vermont Department of Health.

Split samples were provided to both agencies for independent analysis.
According to Larry Smith, spokesman for Vermont Yankee, "The site's hydraulic
studies and sampling data continue to indicate that tritium has not and will not contaminate on- or off-site drinking water supplies." Smith added that a similar sample obtained 100 feet below the contaminated site was free of tritium.
The Construction Office Building well was removed from service as a drinking water well on Feb. 22 as a result of a leak of tritiated water found in January.

"Flow of water in this well behaves according to the established site hydrogeologic model and flows in the direction of the Connecticut River," Smith said. "The flow characteristics within this well column itself are upward, meaning that contamination of the deep aquifer remains highly unlikely."
Samples collected on a daily basis during January and February were continually free of tritium, Smith said.


Although the number of picocuries is extremely small, the finding means something much greater, said Arnie Gunderson, Chief Engineer for Fairewinds Associates, a paralegal and nuclear consulting firm.
"It's not the number that's the concern, but it shows the plume of groundwater contaminates, containing other isotopes, is moving down," Gunderson said. "It means Entergy absolutely needs to keep the extraction wells running, which will prevent anything else from getting into the groundwater.

What worries Gunderson and many others is the possibility of Strontium-90 and Cesium-137, radioactive isotopes, moving into the ground water.
"If Entergy keeps shucking and sucking the tritium out of the soil, it'll prevent the isotope from moving," he said.
Gunderson added that the recent rainfall had nothing to do with the sample being found.
"Rainfall can't be attributed to anything 2 or 3 feet below the ground," he said. "This a gravity problem, which is pulling the tritiated water down further into the groundwater."

The Nuclear Regulatory Commission is currently engaged in an active inspection of the Vermont Yankee groundwater monitoring assessment and remediation program. Hydrologic experts from the Nuclear Regulatory Commission and the U.S. Geological Survey, which is providing support to the NRC inspection effort, have been closely following Entergy's groundwater field studies, monitoring the assessments and are independently evaluating and assessing the information and data developed and analyzed by the company's hydrologic experts, Sheehan said.

"These concentrations are extremely low," he said. "The Environmental Protection Agency's drinking-water standard for tritium is 20,000 picocuries-per-liter, for example."
The Vermont Department of Health had requested a split sample from the contaminated well, which was shipped Friday, according to the department's website. "Vermont Department of Health samples from the Vernon Elementary School and numerous private residences off-site near the plant have not shown tritium levels greater than the lower limit of detection, nor have they measured any other nuclear power plant-related radioactive materials since this tritium investigation began in January," said Dr. Bill Irwin, radiological health chief for Vermont Department of Health. Irwin added that "there's been no indication of other radioactive materials within 10 feet of the contaminated site," and that samples have been and will continue to be taken.
To date more than 265,000 gallons of tritiated water have been remediated from the ground into storage tanks.

Entergy has applied to the NRC to extend the plant's operating license from 2012 to 2032. In addition to NRC approval, Entergy must also receive an OK from the Vermont State Legislature and the Vermont Public Service Board to continue operation past 2012.In February, the state Senate voted 26-4 against the continued operation of the plant beyond its current operating license.