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Out With the Old in With the New

08/20/2019 12:27 PM

..."When the Navajo Generating Station in Arizona shuts down later this year, it will be one of the largest carbon emitters to ever close in American history.

The giant coal plant on Arizona’s high desert emitted almost 135 million metric tons of carbon dioxide between 2010 and 2017, according to an E&E News review of federal figures.

Its average annual emissions over that period are roughly equivalent to what 3.3 million passenger cars would pump into the atmosphere in a single year. Of all the coal plants to be retired in the United States in recent years, none has emitted more.

The Navajo Generating Station isn’t alone. It’s among a new wave of super-polluters headed for the scrap heap. Bruce Mansfield, a massive coal plant in Pennsylvania, emitted nearly 123 million tons between 2010 and 2017. It, too, will be retired by year’s end (Energywire, Aug. 12).

And in western Kentucky, the Paradise plant emitted some 102 million tons of carbon over that period. The Tennessee Valley Authority closed two of Paradise’s three units in 2017. It will close the last one next year (Greenwire, Feb. 14)."....

more...

https://www.scientificamerican.com/article/and-now-the-really-big-coal-plants-begin-to-close/

So it looks like the US will continue to lead CO2 reduction efforts worldwide at least for the foreseeable future...Still waiting for the big nuclear rollout to take this effort to the finish line...

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#1

Re: Out With the Old in With the New

08/20/2019 1:59 PM

So, are the closing coal plants being replaced with less polluting plants (nuclear?) or do we not need the generating capacity? I would think with electric vehicles becoming popular that we would be needing more capacity.

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#2
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Re: Out With the Old in With the New

08/20/2019 2:44 PM

These are being replaced with wind and gas turbine generators...

..."Electricity consumption in the US peaked in 2007 and has declined since, despite population growth of about 24 million people over the 10 years and despite economic growth."...

..."There are a number of reasons for the decline in demand for electricity, including more efficient heating and air conditioning systems, more efficient residential and commercial buildings, the switch to more efficient lights such as LEDs, the offshoring of power-intensive industries that started decades ago, the rise of rooftop solar, etc.

So the pie is shrinking for utilities. There is now no longer any doubt. But there is another interesting aspect to this phenomenon: How that shrinking pie is getting divvied up among the various sectors of electricity generation.

The most glaring aspect is the battle between natural gas and coal. And coal has been losing this battle for a decade for two reasons:

One, technical innovation. The Combined-Cycle Gas Turbine (CCGT) arrived in the 1990s. GE Power – yes, the one mentioned above – has been on the forefront with this technology. The gas turbine operates like a jet engine but drives a generator instead of fan blades. The hot exhaust gases then create high-pressure steam to drive a steam turbine connected to another generator. Thermal efficiencies reach 62% and beyond. Coal-fired power plants only use steam turbines, and thermal efficiencies average 33% globally.

Two, fracking. Starting in 2009, the surge in natural gas production from fracking created what people have called a “glut” in the US. The price collapsed to ludicrously low levels and has remained low, sending some natural gas drillers into bankruptcy.

Over the years, that combination — a highly efficient generating technology and the ludicrously low price of natural gas — has dethroned “King Coal,” cutting its share of power generation from 53% in 2000 to 30% in 2016, and sent a number of coal miners into bankruptcy.

The other winners beyond natural gas are wind and utility-scale solar. In 2000, they generated a minuscule amount of electricity. By 2016, they produced 6.5% more power than hydro.

This chart shows the major sectors of the power-generation portfolio of the US in gigawatt hours generated annually: note the dynamic between coal (black line) and natural gas (red line). While nuclear (yellow line) and hydro (blue line) have remained relatively stable, wind and solar combined (green line) have surged:"...

I'm afraid EV's have not hit their stride yet, so electricity demand is languishing...

https://wolfstreet.com/2017/12/03/us-demand-for-electricity-falls-further-what-does-it-mean/

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#3

Re: Out With the Old in With the New

08/21/2019 2:19 AM

CO2 is a plant food, not a pollutant. See my screed below. The temperature of the Earth is controlled by the clouds, which in turn are controlled by the Sun's solar cycle as explained below. Atmospheric CO2 concentration is minuscule compared compared to water vapor and has almost the same insulating factor. If CO2 were really what was causing the warm up, the water vapor would also have to be eliminated. Remember back in the old days when a large part of the Earth was covered in ice? There was no large release of CO2 release by mankind. And yet, the solar cycle increased, caused fewer clouds, and melted the ice cap all by itself. Then there was the "little ice age" a few hundred years ago when the Thames River in London froze. And later there was a warming period when grapes were grown in Europe farther north than they are now. So the warming and cooling of the Earth is caused by the the Sun in a cyclical manner, and the rise and fall of the CO2 concentration is a consequence of the Earth's temperature change and not the cause of it. I know of only one entity that can control the Sun like that, and it is not mankind.

https://cr4.globalspec.com/comment/1244476/Re-Global-Warming-what-can-we-do-or-should-we-do

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#4
In reply to #3

Re: Out With the Old in With the New

08/21/2019 2:43 AM

While all that may or may not be true, at some point I think we can all agree that we must transition from fossil fuels to renewable sources for our energy needs, and that will take a long time to do....I don't see any problem with starting that transition now...it will probably take over 100 years anyway...I personally think that algae growth in the oceans is the biggest threat...

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#13
In reply to #3

Re: Out With the Old in With the New

08/21/2019 10:14 PM

Regarding CO2 being a plant food, the evidence is much more complicated. Studies in greenhouses, with elevated levels of CO2 have given mixed results. Uptake of CO2 into the ocean has caused a lowering of the pH and has shown problems with creation of crustacean shells.

I am familiar with the historical record of temperature and CO2 levels in the Russian Antarctic ice cores, with the temperature rise leading the CO2 level rise. However, the presently increasing CO2 levels are exclusively due to human activity. The ice core data do not shed light on the question of potentiation, wherein a rise in CO2 then potentiates the prior rise in temperature and makes it greater.

I will take time soon to study the photometrics of H2O versus CO2 versus CH4 see how they compare in terms of being selective absorbers of infrared energy.

Regardless of what is going on, we are using too much energy and are doing so in a way that is not in balance with the planet's resources. The UN published a report a couple decades age in which it was noted that for everyone in the world to have equal access to energy the USA would have to decrease its usage by about 90%. That obviously is unlikely to happen, but the alternative of increases around the world while the USA stays constant is even more frightening.

--JMM

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#14
In reply to #13

Re: Out With the Old in With the New

08/21/2019 11:43 PM

It is not complicated. Plants use CO2 as food. There is no ambiguity there.

Your second opinion does not conform with standard chemistry and real observations in oceans and other water bodies. Can you point to a source that claims that CO2 affects creation of crustacean shells?

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#15
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Re: Out With the Old in With the New

08/23/2019 3:11 PM
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#16
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Re: Out With the Old in With the New

08/23/2019 3:59 PM

We haven't had 2250 ppmV of CO2 since the Precambrian period which was more than 570 million years ago. It was 2250 ppmV in the Cambrian period when the "Cambrian explosion" occurred (when a dramatic burst of life forms came forth).

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#17
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Re: Out With the Old in With the New

08/23/2019 9:13 PM

...." The scientists exposed the tanks to air containing CO2 at today’s level (400 parts per million, or ppm), at levels that climate models forecast for 100 years from now (600 ppm) and 200 years from now (900 ppm), and at a level (2,850 ppm) that should cause the types of calcium carbonate in shells (aragonite and high-magnesium calcite) to dissolve in seawater."...

There is a level of CO2 acidification that causes seashells to dissolve, we are nowhere near that at this time....

..."While ongoing ocean acidification is at least partially anthropogenic in origin, it has occurred previously in Earth's history.[17] The most notable example is the Paleocene-Eocene Thermal Maximum (PETM),[18] which occurred approximately 56 million years ago when massive amounts of carbon entered the ocean and atmosphere, and led to the dissolution of carbonate sediments in all ocean basins."...

https://en.wikipedia.org/wiki/Ocean_acidification

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#32
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Re: Out With the Old in With the New

09/02/2019 6:23 AM

Well, just the question I would have is how stand mussels and other shelled animals in rivers and lakes, fresh water that is, which carry run off of rain, which washes CO2 out of the atmosphaere = slighly more acidic for the run off, up against the acidification?

They do, do they not?

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#5

Re: Out With the Old in With the New

08/21/2019 4:26 AM

The nuclear roll out will trade carbon pollution for nuclear pollution. Which is the worse? A slow death because of carbon pollution or a quicker death from the radiation released from the 50000 year half life of the spent rods? It's foolish to think humans can keep something as dangerous as the spent rods safe for 50000 years!!

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#7
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Re: Out With the Old in With the New

08/21/2019 11:40 AM

We have a solution for nuclear waste, we just haven't used it yet...

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#6

Re: Out With the Old in With the New

08/21/2019 8:09 AM

Some folks are going to see dramatic rate increases. And all will suffer from more frequent power outages

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#8

Re: Out With the Old in With the New

08/21/2019 12:01 PM

To PAPADOC:

Before you worry about CO2 "pollution", you should counter my assertion that CO2 is a plant food, and does not cause a temperature rise as I assert in post #3 of this thread.

If a radioactive element has a 50,000 year half-life, then its radioactive release is very low and easily contained.

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#9
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Re: Out With the Old in With the New

08/21/2019 12:18 PM

Until it's blown up and deposited in the atmosphere.

The risk is too great. Great risks are taken when there's no alternative. Here, there's an alternative.

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#10
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Re: Out With the Old in With the New

08/21/2019 5:52 PM

What's your famous alternative? Wind power? Ha. Out with it!

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#11
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Re: Out With the Old in With the New

08/21/2019 6:29 PM

One alternative is nuclear power with 25 year half life. Use up the existing spent rods to produce the heat to power the turbines to turn the generators. This would cost more per kwh but would be of greater value because of the safety. However, there is a limit as to how much uranium is in the earth just like carbon fuels. So, solar power is the answer. My proposal of a world wide grid of solar energy is the way to go. It's doable. Use the solar power to make hydrogen to power the fuel cells. It doesn't take very long to fill a tank of an automobile with hydrogen. It would be very close to how it's done with the internal combustion engine today. My idea will someday come to past. There's an infinite amount of photons out there to be converted to electrical energy for our personal and industrial use.

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#27
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Re: Out With the Old in With the New

08/29/2019 10:34 AM

How far are you from Georgeown, TX? This town bit the bullet and will suffer far into the future

https://www.foxnews.com/opinion/gree...m-chuck-devore

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#28
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Re: Out With the Old in With the New

08/30/2019 4:42 AM

Yes, Georgetown was a big mistake. It should have been thought out better. Every project must be analyzed from when it comes from the earth until it goes back to the earth. 50000 half-life nuclear spent rods don't go back to the earth very easy. During the interim period before the world wide solar grid is built, SAFE nuclear power can be used. Use up the spent rods. The power will cost more. But most people would be willing to pay more to get rid of the spent rods. Even if it costs 50% more, it would be worth it. All the fossil fuels, uranium, and other ores to make power have a finite amount. Photons from the sun do not.

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#18
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Re: Out With the Old in With the New

08/24/2019 8:50 AM

We heard you the first time...
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#19
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Re: Out With the Old in With the New

08/24/2019 10:00 PM

Ratch,

What is your educational qualification on which you say If a radioactive element has a 50,000 year half-life, then its radioactive release is very low and easily contained.?

I believe you said this in reference to the conviction that nuclear energy is the best source for supplying our energy needs in the future. I would dispute that.

  • No nuclear power plant design is free from the creation of significant amounts of radioactive byproducts, many of which have high levels of gamma and beta radiation with half lives far beyond our country's. This applies to the breeder-type plants that have some promise but are not free of the byproducts, as well as to the more conventional U235-powered plants.
  • A long half-life does not automatically mean safety, but needs much more careful evaluation.
  • The first fission of U235 produces alpha particles which can be stopped by the outermost layer of our skin. However many further steps in the radioactive decay chain are far less benign.
  • Radon (Rn222) is about 5th in the decay chain. It is a chemically inert gas but is also radioactive with a half life of only about 4 days. It also produces alpha particles when it decays, but because it is present in rock formations and seeps into basements worldwide, it is easily inhaled making these alpha particles destructive to the lungs. It is the number 1 cause of lung cancer in non-smokers, and testing or mitigation for it is required in many model building codes.
  • In our pursuit of atom and hydrogen bombs, as well as our pursuit of fuel for nuclear-powered reactors we have mined and purified millions of pounds of uranium, and stockpile it in a number of places in the USA and elsewhere. Because of its metallurgical and chemical properties it is highly desired for use in munitions and armaments by at least 6 different nations. However in this use it burns at an amazingly high temperature and produces microscopic aerosol particles that get inhaled. Once in the lungs these particles cross into the blood stream with most being excreted in the urine within a few days. However during that time, the very long decay time still produces a number of alpha particles directly to cells which get genetically damaged. So these alpha particles are not so innocent!
  • All heavy metals are chemically poisonous; some with toxicities greater than that of the widely-vilified lead. Unfortunately chemical toxicity and radioactive toxicity potentiate each other so the harm we create gets worse.
  • I have worked a number of times in nuclear power plants as well as working with radiation in chemistry labs, and have worn film badges and carried Geiger counters, etc. In these plants there are areas where you do not go or linger, and when certain operations are being done humans are kept far away (with robots doing the work).

A 50,000 year half-life, then its radioactive release is very low and easily contained.? NOT.

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#20
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Re: Out With the Old in With the New

08/24/2019 10:35 PM
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#12

Re: Out With the Old in With the New

08/21/2019 9:20 PM

THE MEAN GREEN POLLUTION MACHINE

The following was written by Harold Hamilton https://anokacountywatchdog.weebly.com/

Ratch

--------------------------------------------------------------------------------------

GREEN’S DIRTY SECRET
The “renewable” energy crowd has long gotten away with propagating an image of the industry as pristine, clean, and nothing but beneficial for the environment.Not true.
Take the wind industry, which is dominated by massive, and growing, wind turbines that dot America’s prairie’s and coast lines.
To start, the turbines are an eyesore, which is why so many liberal NIMBY’s don’t want them in their own backyards.
The vista from the veranda of summer homes on Martha’s Vineyard surely can’t be sullied, even if in the name of saving the planet from the ravages of global cooling, er, global warming, er, climate “disruption.”
Moreover, the turbines every year kill and maim increasing numbers of federally protected birds, including the Bald Eagle.
Most importantly, these turbines are filled with a great deal of metals, much of it mined from jurisdictions with appalling environmental records.
While different models require different amounts of these metals, the “ballpark” estimate of one 3 mega-watt turbine is as follows:
335 tons of steel;
4.7 tons of copper;
1,200 tons of concrete;
3 tons of aluminum;
2 tons of rare earth elements, including neodymium and dysprosium.
Much of these elements and their constituent parts must be mined, which is normally anathema to eco-nut crowd, who spend a lot of time opposing mining.
More troubling, the necessary rare earth metals are mined and processed in China, a country both hostile to American national security and a country sporting a reprehensible environmental record.
It is estimated that China controls over 95% of the world’s rare earth deposits, and has the market cornered in large part because most first world countries won’t issue permits for such mining.
The U.S. wind industry requires between 5 and 6 million pounds of rare earth metals each year.
Note that the mining of neodymium and dysprosium produces radioactive waste on a one to one basis.
For every ton of the mineral mined, it produces a ton of radioactive waste, according to the Bulletin of Atomic Science.
As one can appreciate, China doesn’t have disposal safeguards in place that even come close to protecting people and the environment. Horror stories of Chinese citizens near these mines becoming sick and dying are legion.
Compare that to America, where radioactive waste storage is so thick with standards and safeguards, we can’t even get a permanent storage site in desolate Nevada approved.
Solar panels aren’t a whole lot better.
These panels contain materials like cadmium telluride, copper indium selenide, cadmium gallium (di)selenide, copper indium gallium (di)selenide, hexafluoroethane, lead, and polyvinyl fluoride. Additionally, silicon tetrachloride, a byproduct of producing crystalline silicon, is highly toxic.
There are increasing concerns that these chemicals can be washed out of panels by rainwater. Moreover, they certainly get washed into the ground when panels are broken during severe weather outbreaks like thunderstorms and hurricanes.
In any case, despite the presence of these chemicals, solar panels are currently disposed of by chucking them in landfills.
It is estimated that in 2016, 250,000 metric tons of solar panel waste was produced world-wide.
Moreover, the economics of recycling solar panels don’t turn a profit, meaning that there is no market incentive to recycle the panels in the absence of subsidies.
The bottom line is that “clean” energy isn’t so clean and comes with its own trade-offs.
It isn’t just coal, nuclear, and natural gas that comes with a downside.

--------------------------------------------------------------------------------------------

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#21

Re: Out With the Old in With the New

08/24/2019 10:37 PM

To jmueller:

I was replying to PAPADOC's assertion about a single radioactive element whose half life was 50000 years. I addressed it to him at the beginning of my reply. Your assumption is that I am referring to all the radioactive waste generated by a nuclear plant along with the chemical toxicity. I don't know where you got that idea. My assertion is that if a radioactive element has a 50000 year half-life, then it is low level radiation.

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#22
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Re: Out With the Old in With the New

08/25/2019 2:51 PM

I erroneously emphasized uranium (with a much longer half-life) when protesting your 50,000 year mention of PAPADOC's post. You falsely assume that a 50,000 year half-life qualifies it as low level. The reading I have done says otherwise.

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#23
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Re: Out With the Old in With the New

08/25/2019 10:11 PM

Everything depends on the concentration. Nobody worries about the radioactive carbon 14 from a fossil with a half life of 5700 years. Plutonium 239 is nasty stuff with a half-life of 24000 years, but I assume that they would reprocess and recover such a valuable element instead of disposing of it. Same with U235. Strontium 90 has a half life of 29 years, so if it is kept for 500 years, it should be down to safe levels. The only problem is if the reactor explodes and the radioactives scatter.

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#24
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Re: Out With the Old in With the New

08/25/2019 10:25 PM

What reading? Source(s) please.

More generally, if a radioactive substance has a short half-life, it may be "hot" at the start, but it degrades relatively quickly to "low".

Conversely, if a radioactive substance has a long half-life, that means that it is radiating relatively slowly, maybe not even much more than background radiation.

Proper treatment (if any) depends on which of these conditions applies, and there could be intermediate cases as well.

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#25
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Re: Out With the Old in With the New

08/26/2019 9:24 AM

Friends,

One of my sources was https://www.nrc.gov/reading-rm/doc-collections/fact-sheets/radwaste.htm I checked this against a couple others and they all agreed.

PAPADOC was specifically referring to spent fuel rods when he was talking about the 50,000 year half life. The NRC in the cited post classifies them as high-level waste. Much waste (cleaning supplies, protective clothing, and many other items) from nuclear power plants is low-level and is separately handled in ways that very few people would find problematic.

Since the original post related to the planned closing of the Navajo coal-fired power plant, I suspect we have gotten into a side-bar.

--JMM

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#26
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Re: Out With the Old in With the New

08/26/2019 2:21 PM

Thank you.

One item is still puzzling, though. (Some of) the transuranic wastes are described as much less thermally and radioactively hot than "spent" fuel rods. Then why are they designated as high-level?

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#29
In reply to #26

Re: Out With the Old in With the New

08/30/2019 3:06 PM

..."High-level radioactive wastes are the highly radioactive materials produced as a byproduct of the reactions that occur inside nuclear reactors. High-level wastes take one of two forms:

  • Spent (used) reactor fuel when it is accepted for disposal
  • Waste materials remaining after spent fuel is reprocessed

Spent nuclear fuel is used fuel from a reactor that is no longer efficient in creating electricity, because its fission process has slowed. However, it is still thermally hot, highly radioactive, and potentially harmful. Until a permanent disposal repository for spent nuclear fuel is built, licensees must safely store this fuel at their reactors.

Reprocessing extracts isotopes from spent fuel that can be used again as reactor fuel. Commercial reprocessing is currently not practiced in the United States, although it has been allowed in the past. However, significant quantities of high-level radioactive waste are produced by the defense reprocessing programs at Department of Energy (DOE) facilities, such as Hanford, Washington, and Savannah River, South Carolina, and by commercial reprocessing operations at West Valley, New York. These wastes, which are generally managed by DOE, are not regulated by NRC. However they must be included in any high-level radioactive waste disposal plans, along with all high-level waste from spent reactor fuel."...

https://www.nrc.gov/waste/high-level-waste.html

..."Low-level waste contains mostly short-lived radioactivity and can be handled safely with simple precautions. Intermediate-level waste is more highly radioactive and consists primarily of used reactor core components and resins and filters used to purify reactor water systems. High-level waste is the used nuclear fuel.Nov 6, 2015"...

https://www.nwmo.ca/en/More-information/You-Asked-Us/2015/11/06/11/03/What-is-the-difference-between-low-level-intermediate-level-and-high-level-waste

Classification of nuclear waste by level of radioactivity...

https://www.world-nuclear.org/information-library/nuclear-fuel-cycle/nuclear-wastes/radioactive-waste-management.aspx

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#30
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Re: Out With the Old in With the New

08/30/2019 5:32 PM

That is just a repeat of what I already read, and it doesn't answer my question.

However, it seems that these wastes are being classified by their origin rather than by their current level of radioactivity. There is local controversy about this: the US Department of Energy wants to reclassify some of the waste as low level, because it has gone through a number of half-lives; but WA State is resisting that.

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#31
In reply to #30

Re: Out With the Old in With the New

08/30/2019 8:21 PM

The only difference in high level waste and intermediate level waste is the amount of heat generated...

..."High-level waste (HLW) is sufficiently radioactive for its decay heat (>2kW/m3) to increase its temperature, and the temperature of its surroundings, significantly. As a result, HLW requires cooling and shielding. "...

..."Intermediate-level waste (ILW) is more radioactive than LLW, but the heat it generates (<2 kW/m3) is not sufficient to be taken into account in the design or selection of storage and disposal facilities. Due to its higher levels of radioactivity, ILW requires some shielding."..

So the active cooling of waste is only required if the heat generated exceeds the 2 kW/m3 level...

https://www.world-nuclear.org/information-library/nuclear-fuel-cycle/nuclear-wastes/radioactive-waste-management.aspx

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