"usually do not directly emit radiation" is pretty defensible.
"An operating nuclear power plant produces very small amounts of radioactive gases and liquids, as well as small amounts of direct radiation. If you lived within 50 miles of a nuclear power plant, you would receive an average radiation dose of about 0.01 millirem per year. To put this in perspective, the average person in the United States receives an exposure of 300 millirem per year from natural background sources of radiation."
[1] https://www.nrc.gov/about-nrc/radiation/related-info/faq.htm...
"As a general clarification, ounce for ounce, coal ash released from a power plant delivers more radiation than nuclear waste shielded via water or dry cask storage." (emphasis mine)
By adding the qualification "shielded" the comparison becomes meaningless. Brazil nuts, bananas, beer, carrot juice and drinking water [2] all release more radiation than shielded nuclear waste.
Nowhere in the SA article they compare coal ash with Chernobyl of Fukushima.
[1] https://www.scientificamerican.com/article/coal-ash-is-more-...
[2] https://www.thoughtco.com/common-naturally-radioactive-foods...
https://www.nrc.gov/docs/ML1036/ML103620452.pdf
Power reactors discharge a small amount of radioactive material into the environment under normal operating conditions. See figures 4.1 through 4.12 in the report. The Palo Verde Nuclear Generating Station in Arizona [0] released 1844 curies of radionuclides in a year from gaseous, liquid, and particulate discharges. In SI units, that's 6.8 * 10^13 becquerels.
According to the World Nuclear Association, a kilogram of coal ash contains about 2000 becquerels of radioactive material [1]. In 2012, the United States coal fleet generated about 110 million tons of coal ash [2]. In 2012, the United States generated 1514 terawatt hours of electricity from coal [3]. That puts the coal ash radioactive burden to the environment at roughly 1.45 * 10^11 becquerels per TWh of electricity generated in coal plants.
The Palo Verde annual radioactive effluent discharge of 6.8 * 10^13 becquerels from an average of 32.3 TWh electricity generation [0] comes to 21 * 10^ 11 becquerels per TWh of electricity. Its radioactive discharge to the environment is significantly higher than the average discharged via coal ash to produce an equivalent amount of electricity.
However, before getting alarmed, see figure 2.1 in the NRC Radioactive Effluents report that I linked at the beginning of this post. Even though nuclear plant effluent adds more radiation to the environment than coal ash does, industrial sources of radiation (including nuclear plants) account for about 0.1% of general population radiation exposure. Natural background sources add up to about 50%. So the marginal danger of radioactive exposure from normally operating nuclear plants or coal ash dumps is very small.
People who say that coal plants emit more radiation than nuclear plants are not helping to counter "radiophobia." They are in fact attempting to exploit "radiophobia" to stir up fear over a very minor aspect of coal's environmental harms. (And coal really is an environmental disaster in many other ways.) Worse, people making this argument are not even correct about the underlying numbers. Many of them are just parroting a Scientific American article [4] which itself is a misleadingly garbled retelling of an actual research report [5] [6].
[0] https://en.wikipedia.org/wiki/Palo_Verde_Nuclear_Generating_...
[1] http://www.world-nuclear.org/uploadedFiles/org/Features/Radi...
[2] https://www.epa.gov/coalash
[3] https://en.wikipedia.org/wiki/Energy_in_the_United_States#El...
[4] "Coal Ash Is More Radioactive Than Nuclear Waste" https://www.scientificamerican.com/article/coal-ash-is-more-...
[5] "Radiological Impact of Airborne Effluents of Coal and Nuclear Plants" https://science.sciencemag.org/content/202/4372/1045
[6] Detailed examination of what the authors were actually reporting in "Radiological Impact of Airborne Effluents of Coal and Nuclear Plants" via my past comment here: https://news.ycombinator.com/item?id=14466887
Do we have data/studies on the health effect comparison of the radioactive portion of emitted coal ash and the typical emitted/discharged effluents of a nuclear power plant?
Eg. isn't the NPP discharge much more localized so it affects a lot less people? Or both kinds have some of this and some of that and the gases are carried well with the wind anyway?
Most of the discharge from coal plants modeled in "Radiological Impact of Airborne Effluents of Coal and Nuclear Plants" was from traces of radium discharged from the smoke stack along with other combustion products. Since radium behaves chemically like calcium, and is taken up into plants and the bones of people who eat those plants, it can have a much greater effect on human radiation exposure even though the coal plant discharging fewer curies of radioactive material to the environment.
A modern do-over of the 1978 study would need to take into account a few things:
- Smokestack emissions of radionuclides from coal have been incidentally reduced by other anti-pollution measures required on coal power plants in the US. Ash precipitators, SO2 scrubbing, and mercury scrubbing will all cut down somewhat on radium escaping via the smokestack. (None of this helps with coal's CO2 profile, but it does reduce other pollution hazards.)
- Operational changes have reduced how much effluent nuclear power plants discharge into the environment -- even if the plant was already built in the 1970s. It should use more recent effluent numbers like those in "Radioactive Effluents From Nuclear Power Plants: Annual Report 2008" rather than 1970s NPP effluent numbers.
- Locality of food production/consumption has decreased since 1978. The original study assumed that people ate food grown in the same region they live in, so that radioactive effluents from power plants affected local populations via the agricultural food chain. It will change if people living near a power plant in Maryland are eating foods mostly produced out-of-state.
If we look at all the NPPs (so we factor in all the accidents) and average out then we get a higher number.
And if we look at a full lifecycle analysis (so from uranium oxide mining to plant building, to long-term nuclear waste storage, and/or reprocessing and whatnot), then we'll get an even higher number.
But all of that is quite meaningless, because the real question is health impact anyway.
There are a lot of interesting things you could say about this.
A coal plant needs workers and it also needs good transportation links. (To bring the coal in.) It needs to support the workers. It needs to be hooked up to an electrical grid. So it's sort of a natural nexus for the development of a city. People who can live in some other city might prefer that, but there will be plenty of people for whom the Coal City is a natural choice. If cities naturally grow around coal plants, then it doesn't make sense to be surprised that there are cities with coal plants in them.
Taking the original comment in a totally different direction, this is an angle I don't think is discussed enough in relation to electric cars. We may not need to burn coal inside cities, but we burn oil all the time, so we can move around. This produces the same undesirable smog that coal does. There's a big fight over whether electric cars release more or less smog well-to-wheels than gasoline cars do. But I almost never see anyone asking whether, even if electric cars release more smog, it might not be better to have the smog all produced centrally at a power plant somewhere than widely distributed in the middle of concentrated residential areas.
You can site a power plant regionally, it doesn't have to be particularly adjacent to residences.
In less literal terms, there might be a debate about relative amounts of CO2. But that is mostly a debate that happens online instigated by ideological opponents of electrification. Electric cars use less energy even including production and even if the energy mix consists mostly of fossile fuels. See https://en.wikipedia.org/wiki/Environmental_aspects_of_the_e....
The advantages are even starker for other emissions such NOX or particulates: even without renewables and nuclear energy in the mix, electric cars need less energy because the efficiency of one large power plant is higher than thousands of engines. And that energy is generated with fewer emissions because, again, centralized generation allows more investment into clean technology.