An unidentified leak of tritium has been detected at several of the monitoring wells at Indian Point nuclear facility in New York state. What is tritium? What are the likely implications of this release? And, what actions should we consider moving forward?
Indian Point is a nuclear power plant located just south of Peekskill, NY with generating capacity over 2,000 MW of electrical power. Entergy Corp., the owners of Indian Point recently reported that radioactive tritium has been detected in groundwater testing wells at the facility.
The latest headlines I saw today warned: “tritium leak 80% worse than originally reported”. Several days ago the headline said: “65,000% Spike In Reported Radioactivity After Tritium Leaks At Indian Point Nuclear Power Plant”. That sounds scary. Really scary! But what does it really mean?
What Is Tritium?
Tritium is a radioactive isotope of hydrogen. Because it is an isotope of hydrogen, under the right circumstances, it has the ability to combine with oxygen to form “tritiated” water. Since tritium is a weak beta emitter whose beta particles are unable to penetrate human skin, ingestion of tritiated water provides the only realistic mechanism of risk posed by tritium. The good news is that even if it is ingested, the risk of real harm is still extremely low. Two factors contribute to minimizing the risk. Tritium’s relatively long half life of 12 years means that it is not particularly radiologically active. It’s short biological half life of 10 days means that any tritium ingested will be eliminated fairly quickly.
Is It Dangerous
Most countries establish acceptable levels of various impurities in their drinking water and many countries have established acceptable safe levels of tritium. For example, the US has a safe limit of 740 Bq/l (becquerels per liter). A becquerel is a measure of radioactivity similar to a sievert, rem, rad, gray, or curie. The limits established for each country vary, but they are all within a bandwidth that guarantees any effect is so small so as to be undetectable.
Would you be surprised to find that many countries have significantly higher limits than the US? The World Health Organization (WHO), for example, recommends a limit of 10,000 Bq/l (1,351% higher than the US). Finland sets its limit at 30,000 (4,054% higher than the US). And Australia has a limit of 74,103 (10,014% higher than the US).
Tritium Is Common
Tritium is also commonly used in the ubiquitous exit signs seen over doors in schools, offices, government buildings, etc. These signs use tritium because it is self illuminating in the event of a power failure. Each sign typically contains around 25 curies (Ci) of tritium. Although these signs are regulated, they regularly find their way into landfills or are otherwise improperly disposed of.
How Bad Was It?
For comparison purposes, the worst measurement at Indian Point was 8,000,000 picocuries/l (or 296,000 Bq/l). Now keep in mind, this was measured in a test well withing the plant itself. There has been none detected anywhere outside the plant.
Also consider that the water from the worst test well is just 4 times the level considered safe for drinking by the government of Australia. It also means that it requires 940,000 liters of water from that well to get the same amount of tritium contained in a single self illuminated exit sign.
Let me be clear, I am not pointing this out to suggest we should do nothing. However, I am concerned that the level of alarm that has been raised over this is totally out of proportion with the event. And I am worried that we could make decisions based on ignorance, fear, or duplicity that would result in greater and longer term harm to the environment.
The Indian Point reactors generate over 2000MW of electricity and they have one of the highest capacity factors (a measure of performance reliability) of any power plant anywhere in the world. With an enviable capacity factor of 93%, Indian Point produces over 16,000 GWh of CARBON FREE electricity annually. Compare that to solar and wind which typically have capacity factors in the 10-25% range.
There is no doubt, if these reactors are shut down their generating capacity will be replaced by fossil fuel plants. This is a huge problem. Indian Point electric generation capacity will likely be replaced by natural gas resulting in an 8,000,000 tons of CO2 emissions per year.
The Moral Imperative
Carbon is a difficult problem; far more difficult than fixing the ozone hole, or cleaning up our lakes and rivers. It is vastly more difficult that cleaning up the smog in our atmosphere. It is more difficult than these because it is a fundamentally different kind of problem. In each of the other problems, once we address the root cause, the situation starts to improve. If we stop pumping noxious chemicals into the air or the water, natural processes start to cleanse them. This cleansing process happens on a reasonably short scale; months, years, or at most a few decades. The problem with carbon is that once it’s pumped into the atmosphere, it is there to stay. There is no way to get it back out – at least not on any reasonable time scale. Because of this, most climate scientists have concluded that almost all the fossil fuels currently in the ground need to stay there.
Global warming, carbon pollution and the associated effects on the biosphere are not something you or I need to face. The real devastating effects are probably far enough in the future that we will be gone. Carbon is a problem for the young. It is our children and all the following generations that will have to clean up our mess. This is why James Hansen calls it a problem of inter-generational injustice. And that is why pumping millions of tons of CO2 into the air each year is not only a problem, but a moral dilemma as well.
The problem with Fossil Fuels doesn’t end with climate change.
If you are old enough to remember the events of 26 December 2004, then I am sure you do remember them; or at least I am sure you will when I remind you. That’s the day the Indian Ocean tsunami struck killing 230,000 people across Southeast Asia. Since that day, another kind of tsunami, a silent kind, has struck over and over again killing more than 2.5 million people. Anil Markandya and Paul Wilkinson in an article in The Lancet have calculated that coal use results in 210,000 deaths each year. That is a virtual annual repeat of the 2004 tsunami. Jim Hansen and Pushker Kharecha of the NASA Goddard Institute for Space Studies and Columbia University Earth Institute, have published results showing that global nuclear power has prevented 1.84 million air pollution-related deaths and 64 gigatonnes of CO2 emissions that would have resulted from fossil fuel burning.
So what about natural gas? Although natural gas is a lot better than coal, replacing Indian Point with natural gas still results in increased CO2 emissions of 1200 tons per year. Natural gas has the additional impact of large and indeterminate methane emissions. Methane is 30 times more potent as a greenhouse gas as CO2. Also, a large and increasing volume of natural gas production relies on fracking. Increased use of natural gas will inevitably increase the demand for and use of fracking.
Although no one should go out an find a well full of tritiated water and start drinking it, it’s important to keep the risks in perspective so they don’t cause us to make rash choices with unintended, less desirable consequences.