The Radiological Health Program evaluates and manages the actual and potential public health impacts on Vermonters from activities at the Vermont Yankee Nuclear Power Station, located in the town of Vernon in Windham County.
Environmental Surveillance and Monitoring reports
The Health Department continuously measures the radiation dose around Vermont Yankee, both at the site boundary as well as locations throughout Windham County. On a regular basis, samples are collected around the power station to test for radioactive contamination. Samples are taken from:
- surface water
- Connecticut River sediment
- fish from the Connecticut River
Local farms provide milk samples every month for testing to verify there are no radiological contaminants in the milk. Analysis of samples is done at the Health Department Laboratory.
Once every month, the Health Department Laboratory tests private drinking water supplies of selected locations near the Vermont Yankee site boundary. To date, none of these wells have shown contamination with tritium or other radionuclides that would be associated with a nuclear reactor.
Environmental surveillance has been in effect since before Vermont Yankee began commercial operation in 1973. The Health Department publishes an annual report of its surveillance findings—see the reports in the table below.
In 2005, there was an investigation into whether the State’s radiation limit at the Vermont Yankee site boundary had been exceeded. A third party was brought in to conduct the investigation and found Vermont Yankee had not gone over the site boundary radiation dose limit. Read the investigation
|2006 Vermont Yankee Surveillance Report|
|2007 Vermont Yankee Surveillance Report|
|2008 Vermont Yankee Surveillance Report|
|2009 Vermont Yankee Surveillance Report|
|2010 Vermont Yankee Surveillance Report|
|2011 Vermont Yankee Surveillance Report|
|2012 Vermont Yankee Surveillance Report|
|2013 Vermont Yankee Surveillance Report|
|2014 Vermont Yankee Surveillance Report|
|2015 Vermont Yankee Surveillance Report|
|2016 Vermont Yankee Surveillance Report|
|2017 Vermont Yankee Surveillance Report|
Tritium Contamination Investigation
Tritium is a radioactive form of hydrogen. It is a byproduct of the nuclear fission process in a nuclear reactor and occurs naturally in the environment at very low concentrations. Most tritium in the environment is in the form of tritiated water, which easily moves about in the atmosphere, bodies of water, and in soil and rock.
On January 7, 2010, the Health Department was notified by Vermont Yankee Nuclear Power Station that samples taken from a groundwater monitoring well on site at the plant contained tritium. It ended up being an unintentional underground release of radioactive material. This also meant that other radioisotopes could have contaminated the environment, which soil testing confirmed. Although the soil at Vermont Yankee has been contaminated with radioactive materials, there is no known exposure or risk to the public.
More Information on Tritium
- Health Department Investigation 2010 – 2012
- Information about Tritium—Environmental Protection Agency
Testing Private Drinking Water
If you are a Vernon resident or are interested in having your well water tested for tritium, the laboratories listed below can test private well water for tritium.
The State of Maine Health and Environmental Testing Lab
Contact person: Pat Boudreau
Test America Inc. – Richland Washington
Phone: 509-375-3131 ext. 164
Contact person: Christi Hayes
This is a private lab, not a public health lab.
Westchester County Department of Labs and Research
Contact person: Robert Hilbrandt, Jr.
Please contact the laboratories directly for information about sampling bottles, the quantity of water needed, turnaround times and cost.
Testing Soil for Radiation
Soil samples were taken from various locations and depths below the excavation area outside the Advanced Off-Gas (AOG) pipe tunnel that was found to have caused the leak reported on January 7, 2010. Strontium-90, cesium-137, zinc-65, manganese-54
In the February 26, 2010 set of soil samples, strontium-90
In the March 17 and 18, 2010 set of soil samples, cesium-137 was found at as much as 75 times what would be expected in surface soils. Analysis by Vermont Yankee of concrete mud and construction debris in the AOG pipe tunnel also confirmed the presence of cesium-137. See soil sample results for March 17, 2010
At the request of the Health Department, samples of mud and construction debris from within the tunnel were also taken for analysis. Split samples were analyzed by the Health Department Laboratory. Samples were also analyzed by an independent laboratory under contract with the Health Department for “hard to detect” radionuclides such as strontium-90, iron-55
As part of its ongoing environmental surveillance, the Health Department has tested soil samples from two sites in the state not associated with Vermont Yankee and confirmed cesium-137 at concentrations consistent with past nuclear fallout. In 2008, cesium-137 was measured at 86 and at 168 picocuries per kilogram (pCi/kg).
Radioactive Elements Found in the Soil at Vermont Yankee
Strontium-90 and cesium-137 are both products of nuclear
Strontium-90 is considered one of the more hazardous of the radionuclides associated with nuclear reactors. It is a strong beta emitter. This means that its radiation can dose our skin, but it is stopped by a layer of wood, a sheet of aluminum, or sometimes clothing. It behaves chemically much like
Cesium-137 is a moderately strong gamma emitter. This means that its radiation can pass through the human body, stopped only by a lead shield or several feet of concrete.
These isotopes give off radiation and decay over time. The “half-life” is the length of time it takes to decay to one-half of its original concentration. Zinc-65 has a half-life of 244 days. Manganese-54 has a half-life of 313 days. Cobalt-60 has a half-life of 5.3 years and is a strong gamma emitter. This means that its radiation can pass through the human body and is stopped only by a lead shield or several feet of concrete.