I belong to a generation that grew up with a fear of nuclear war, fall-out and slow, agonizing death by radiation poisoning. We’d seen the horrors of Nagasaki and Hiroshima. We lived through the scare of Three Mile Island and, years later, had our fears reinforced by catastrophes at Chernobyl and Fukushima. Given the fear of radiation, when people talked about the wonders of nuclear power, my reaction was, “Sounds great. Just make it safe.”
As the United States evolves toward a low-carbon future, nuclear energy has two great virtues. First, it emits zero carbon dioxide. Second, nuclear power plants run around the clock; unlike with wind and solar, output does not vary with weather conditions. The drawback is that nuclear units are hideously expensive to build, largely because federal rules have zero tolerance for radiation leaks.
The zero-tolerance philosophy is based upon a scientific premise known as the linear no-threshold model (LNT), which states a linear dose-risk relationship. We know incontrovertibly that large radiation doses are deadly. The LNT model asserts that small doses are damaging as well, though at proportionately lower levels. While that scientific view has prevailed in the regulatory arena — better safe than sorry — it has not been universally accepted.
Proponents of “radiation hormesis” argue that biological organisms evolved in an environment with measurable background radiation. Not only is this low level of radiation not harmful, says the hormesis hypothesis, it is beneficial because it stimulates organisms to engage in cellular repair activities that counter not only the deleterious effects of radiation but cancers unrelated to the radiation exposure. The positive hormesis effect small, however, so its statistical signal has been drowned out by seemingly infinite variations in environmental conditions and by measurement error.
Still, the hormesis hypothesis has been gaining traction in recent years — so much so that the U.S. Nuclear Regulatory Commission has requested public comment on proposals to change the basis for NRC “Standards for Protection Against Radiation” from the LNT model to the hormesis model. Presumably, the proposed change would declare low levels of radiation emissions to be harmless, which in turn could relax the regulatory requirements surrounding the construction and operation of nuclear reactors.
“Exaggerated radiation fears have been crucial in driving up the safety, waste storage and licensing costs of nuclear power,” declares Holman W. Jenkins Jr. in the Wall Street Journal today. “But change may finally be coming—a paradigm shift in how we think about nuclear risk.”
While sentiment may be shifting, millions of Americans remain less than convinced. Most of the comments I perused in the NRC comments were negative. Many people are convinced that the revised thinking is being driven by a self-serving nuclear power industry.
There is a good chance that the LNT-vs.-hormesis debate will come to Virginia. Dominion has filed for NRC regulatory permission to extend the life of its two Surry nuclear power units, and has spent hundreds of millions of dollars to keep alive the option of building a third nuclear unit at its North Anna power station. Environmental groups, most notably the Virginia chapter of the Sierra Club, have campaigned actively against the nuclear option.
Bacon’s bottom line: What’s fascinating about the NRC’s look at hormesis is that it comes from a Democratic administration, which, all other things being equal, one would expect to be far more responsive to environmentalist concerns than a Republican administration. In a conference on nuclear power last month that generated little attention in the media, the White House reiterated its commitment to nuclear as a necessary component of its clean energy policy.
While Dominion’s proposal to invest roughly $1.5 billion to patch up the Surry units so they can operate another 20 years may be economically defensible, it is hard to see any case being made for spending $19 billion to build a third North Anna unit…. unless Dominion is banking on major regulatory changes at the NRC. If the Obama administration embraces hormesis as the basis for its rule making, and if the new standards strip billions of dollars of expense from building new nuclear reactors, Dominion’s commitment to North Anna 3 makes more sense.
Whatever the NRC decides, fear of radiation is so deeply embedded in our popular culture that the LNT-hormesis controversy is sure to play out here in ye Olde Dominion.