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Step by Step: Understanding Tritium at Watts Bar

Understanding the Plan to continue production of nuclear weapons tritium at Watts Bar one step at a time:

1. The United States demolished the long-standing and internationally recognized wall between commercial and military nuclear power when it decided to produce tritium (a special isotope of hydrogen”H3) for nuclear weapons at the Watts Bar reactor in Spring City, TN, in 1999.

2. The US attempted to explain away its hypocritical decision by separating radioactive materials for nuclear weapons into two categories: Special Nuclear Materials”highly enriched uranium and plutonium”which are still forbidden, and Tritium, which is now okay because we say so.

3. Tritium is used in thermonuclear warheads to boost the effective yield of the bomb.

4. Tritium is highly radioactive. It has a half-life of 12.3 years”this is a relatively quick decay period (plutonium, by comparison, has a half life of 24,000 years; uranium’s half life is more than 700 million years.

5. A “half-life” measures the decay (as a result of escaping energy through radioactive particles or rays) of a radioactive element. Imagine a block of “pure” uranium weighing 100 pounds. If you leave it sit for 710 million years, when you return it will be 50 pounds of uranium. The rest will be something else in the decay chain. Some will be radon. Some will be lead (the ultimate stable state). The stages Uranium goes through as it decays to lead are called the “daughter products” of uranium. Some of them are more dangerous than uranium (like radon).

6. In the case of tritium decay, an excess neutron is converted to a proton by the expulsion of an electron (energy released in the form of a beta particle), and tritium becomes a more stable element”Helium.

7. Radioactive material also has a “biological half-life.” This is the length of time a radioactive material is hazardous to living creatures. As a rule-of-thumb, the biological half-life of a quantity of radioactive material is ten times its radiological half-life. So Tritium’s radiological half-life is 12.3 years; it is dangerous for 120 years.

8. Because tritium decays relatively quickly, it has to be replenished in nuclear warheads. (A warhead that is 36 years old would only have 1/3 the tritium it started out with). That is why the US “has” to produce more tritium for bombs.

9. Tritium is a very difficult material to capture; as an isotope of hydrogen, it behaves like hydrogen, a gas. When Oak Ridge National Lab used to make tritium for commercial applications (runway lights, exit signs, etc) they got complaints from vendors who said they were not receiving the full amount of tritium in their deliveries. So ORNL did an experiment. They packaged a known quantity of tritium, drove it from one end of the site to the other and, when it arrived, sure enough, it had less tritium. One lab worker said, “If you package a liter of tritium in a double-wall stainless steel vacuum thermos and leave it on the table while you go to lunch, when you come back, you can wipe tritium off the outside of the container.”

10. In 1999, The Department of Energy gave itself permission to produce tritium for nuclear weapons at Watts Bar and Sequoyah reactors. (Only Watts Bar has been used so far). They had to use a TVA reactor because no private utility wanted to take the additional risks associated with this novel operation.

11. The process takes several steps. First, specially formulated fuel rods are loaded into the reactor along with the regular fuel rods. The special rods are call TPBARs (Tritium Producing Burnable Absorber Rods, if you must know).

12. While the fuel is irradiated in the reactor, the TPBARs produce and capture tritium that is a natural byproduct of fission reactions. But they are designed to do this on purpose, efficiently.

13. In the 1999 Environmental Impact Statement, DOE estimated some tritium would escape (permeate the casing, or leak) from the TPBARs and enter the reactor cooling water and eventually be discharged into the environment (the Tennessee River). DOE estimated releases as much as 1 curie per year per rod.

14. There are between 1800 and 2400 TPBARs in the reactor during a standard 18 month fueling period.

15. A curie is a huge amount of radiation. For the purposes of protecting humans from radioactive materials, measurement of picocuries, nanocuries, and microcuries are used. A picocurie is one trillionth of a curie. A nanocurie is one billionth of a curie. A microcurie is one millionth of a curie.

16. After running the TPBARs through Watts Bar for 18 months, the bars are off-loaded, cooled (they are too hot to handle) and eventually shipped to Savannah River where a special tritium extraction facility has been built to get the tritium out of the rods.

17. Once the tritium operation was up and running, DOE/NNSA decided to check their figures (by now, Congress had created the National Nuclear Security Administration to do the dirty work of nuclear weapons). They discovered they had underestimated the amount of tritium leakage. It was 3-4 times as much as they had predicted. Meaning as many as 10,000 curies a year were being released into the Tennessee River.

18. Tritium, because it is an isotope of hydrogen, is especially pernicious in the environment. It acts like hydrogen, bonds with oxygen, and is almost impossible to get out of water. So it gets drunk, it enters the bloodstream, penetrates cell walls, does everything water does.

19. Several years ago, NNSA decided the new information required a new look at the tritium program, and they decided to prepare a Supplement to the original Environmental Impact Statement. They held scoping hearings (hardly anyone went to Athens for the hearing; less than a dozen regular citizens were there). And they prepared their Draft S-EIS.

20. That Draft S-EIS was released earlier this month. It can be found on the web.

21. The Draft says the NNSA no longer thinks it needs to use Sequoyah (but retains it as a backup) because the amount of tritium needed is less than forecast in 1999. The Draft also says releasing ten thousand curies of tritium a year into the Tennessee River is not a problem. And NNSA will continue to violate international nonproliferation norms and produce weapons materials in the commercial reactor at Watts Bar.

22. The Institute for Energy and Environmental Research in Takoma Park, MD has challenged the government’s limits on radiation exposure, noting they are calibrated to an adult male and ignore differing effects on women, fetuses, etc. Even so, using the government’s highly permissible levels of “safe” exposure, one ounce of tritiated water would be enough to contaminate the entire annual flow of the Savannah River above the present drinking water limit.

23. Along with the release of the Draft, NNSA announced two public hearings to receive comments on the Draft. One is Tuesday, September 9 in Athens; the other is Wednesday, September 10 in Chattanooga.The period for accepting public comments closes on September 22, 2014.

24. No public meeting will be held in Spring City, Tennessee, where the Watts Bar Plant is located or in downstream communities whose drinking water is considered impacted by effluent from Watts Bar except for Chattanooga.


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Sunday Vigil at Y-12 in Oak Ridge Tennessee

Sunday Vigil

OREPA has held Sunday vigils every week for more than 22 years at the main entrance to the Y-12 Nuclear Weapons Complex (intersection of Scarboro Rd and East Bear Creek Road). We will now be holding the vigil at 4:00PM ET during the winter months so we don’t have to be sitting out in the dark. We are outdoors and space our chairs; when covid numbers are up, we encourage people to wear masks. Bring your own chair, we have some umbrellas for sun shade or rain.

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