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According to a US EPA document on depleted uranium, it can also have other deadly, long-lived radionuclides, such as plutonium, americium, and technetium:
US EPA Brian Littleton
Depleted Uranium, Technical Brief,EPA 402-R-06-011, December 2006 http://www.epa.gov/rpdweb00/docs/cleanup/402-r-06-011.pdf
Nuclear Industry Cycle http://web.evs. anl.gov/uranium/guide/uf6/index.cfm
USNRC Comment: Low-Level Radioactive Waste Disposal
ID: NRC-2011-0012-0077 Due Jul 24 2015, at 11:59 PM ET
http://www.regulations.gov/#!documentDetail;D=NRC-2011-0012-0077 Final rule info: http://www.gpo.gov/fdsys/pkg/FR-2015-03-26/pdf/2015-06429.pdf Docket ID: NRC-2011-0012 Nuclear Regulatory Commission (NRC) 10 CFR 60 and 61

Yet another dirty secret of nuclear energy is that for every kilogram (2.2 pds) of enriched uranium, around 7 kg (3% enrichment) to 10.8 kg (5% enrichment) of depleted uranium waste is made. Some countries, such as France, are storing it above ground in metal sheds. The US doesn’t have enough people in the world to shoot the Depleted Uranium (DU) at, though they have tried, and so, EnergySolutions has depleted uranium stacked up in similar sheds but wants to bury the DU, along with other radioactive waste, at its Clive dump, west of the Great Salt Lake-Salt Lake City, Utah. [1] https://miningawareness.wordpress.com/2015/07/21/reclassifying-nuclear-waste-to-dump-on-states-bury-us-nrc-comment-deadline-friday-24-july-11-59-pm-nyc-dc-et/
Clive Utah zoom out
Large nuclear reactor parts, like San Onofre’s old steam generators, and probably their new defective ones too, also get dumped at Clive in Utah, as so-called low level waste. As can be seen in these images, it is a true radioactive junkyard.
Clive Utah zoom in variety waste
Low Level Waste is any radioactive waste not classified as high level or TRU waste. Examples include slightly contaminated soil, D&D debris, protective clothing, job-control waste, equipment, tools, filters, rags and papers. In FY2009, 5,476 cubic meters of solid Low Level Waste were accepted for on-site disposal“. http://www.srs.gov/general/programs/solidwaste/
SRS site to Utah DU
Savannah River Site-DOE Drums containing depleted uranium oxide being loaded into railroad cars bound for Utah. http://www.srs.gov/general/programs/solidwaste/
Can we zoom in a bit on that rust?
zoom of SRS to Utah DU drums
Whereas the original image says that it is for “treatment” in Utah, the image courtesy of Energy Solutions to the Salt Lake Tribune, shows the same rusty oil drums – even rustier – stacked up in a large tin shed. Here’s a zoom in of the rustiest drums in the EnergySolutions picture.
Zoom of ES rusty drums

So, what treatment? It apparently already underwent deconversion to uranium oxide. The only facility is in Tennessee: “As uranium-235 (U235) is extracted, converted, and enriched in the uranium recovery, conversion, and enrichment processes for use in fabricating fuel for nuclear reactors, large quantities of depleted uranium hexafluoride (DUF6), or “tailings,” are produced. These tailings are transferred into 14-ton cylinders which are stored in large yards near the enrichment facilities. A process called “deconversion” is then used to chemically extract the fluoride from the DUF6 stored in the cylinders. This deconversion process produces stable compounds, known as uranium oxides, which are generally suitable for disposal as low-level radioactive waste.http://www.nrc.gov/materials/fuel-cycle-fac/ur-deconversion.html

To show these images means that either Energy Solutions is surprisingly honest or they really don’t know what they are doing. West of the Great Salt Lake is probably salty too, which will speed up corrosion. See picture of DU in shed, awaiting burial, here: http://www.sltrib.com/home/2484177-155/will-depleted-uranium-be-a-time Uranium is a metal and so are the drums. Of course, EnergySolutions investment bankers probably wouldn’t have heard of galvanic corrosion, nor understand that it’s a problem.

The Utah DEQ, and Areva, show these containers. Are the oil drums stacked up in these?
DU Box

The Utah DEQ has lots of info about DU and the Energy Solutions Dump site, west of the Great Salt Lakes: http://www.deq.utah.gov/businesses/E/EnSolutions/depleteduranium/performassess/index.htm

When the rules were originally made, the NRC claims to have not anticipated enriching so much uranium in the US, which is kind of strange because that’s when many nuclear reactors had been recently built and some were still under construction, though it was a few years after the Three Mile Island nuclear accident. Perhaps they didn’t anticipate enrichment for export?

But, there’s a lot more than that. The real issue here appears to be the diluting of nuclear waste with fillers of various sorts, or mixing more and less radioactive waste together, so that it can be passed down to States and buried.

Why do the regulatory requirements need to be revised?
Recently, the industry and the NRC have identified new LLRW streams that were not envisioned during the development of 10 CFR part 61. These LLRW streams include depleted uranium (DU) from enrichment facilities, LLRW from the U.S. Department of Energy (DOE) operations, and blended LLRW streams in quantities greater than previously expected
….
The blending of different classes of LLRW could also result in LLRW streams with concentrations that are inconsistent with the assumptions used to develop tables 1 and 2 of 10 CFR 61.55. Blending of LLRW would enable some materials that would otherwise have been disposed of as a higher class (e.g., Class B or Class C LLRW) to be blended with a lower class (e.g., Class A LLRW) or lower concentration LLRW of the same class. The result of the blending process would be to create large volumes of blended LLRW that have concentrations near the LLRW classification limits. The NRC did not evaluate the disposal of large volumes of LLRW with concentrations near the LLRW classification limits in the final regulatory basis for the current 10 CFR part 61.
” Federal Register / Vol. 80, No. 58 / Thursday, March 26, 2015 / Proposed Rules, 16087-16088

The Federal Gov washes its hands of so-called low level radioactive waste A, B, and C, and dumps responsibility upon the States. They keep fat pork barrel for themselves, but anything that costs money, they dump on the States: “In addition to determining the acceptability of LLRW for disposal in a near-surface land disposal facility, the LLRW classification system is also integral to determining Federal and State responsibilities for LLRW and requirements for transfers of LLRW intended for disposal. The Low-Level Radioactive Waste Policy Act of 1980 (as amended in 1985) defines Federal and State responsibilities for the disposal of LLRW based on 10 CFR 61.55, as in effect on January 26, 1983. Specifically, the Act assigns responsibility for disposal of Class A, Class B, and Class C commercial LLRW to the States and responsibility for disposal of commercial LLRW with concentrations that exceed the limits for Class C LLRW to the Federal Government.” Federal Register / Vol. 80, No. 58 / Thursday, March 26, 2015 / Proposed Rules, 16085 http://www.gpo.gov/fdsys/pkg/FR-2015-03-26/pdf/2015-06429.pdf

What is Technetium 99?

Last year, when reading about Technetium 99, we recall finding info saying that because it is so dangerous, it is only used to check and see if patients are brain dead. Perhaps this was forgotten historic research? It is still used, however, to see if patients are brain dead. This year, all we find is how widely used it is for medical procedures and the following:

Re Techetium at Hanford: “Technetium-99 is difficult to treat. It is soluble and mobile in groundwater. It can be taken up by plants and animals. It has a long half-life and remains dangerous for thousands of years.

Click to access 1005007.pdf

The US EPA:
Where does Technetium-99 come from?

Technetium-99 is produced in commercial quantities mainly as a by product from the operation of nuclear reactors. Most of the Tc-99 produced in a nuclear reactor originates from the fission of uranium-235. The Tc-99 produced in the reactor may become part of its airborne, liquid, or solid wastes. In addition to being produced in nuclear reactors, Tc-99 is produced in the detonation of nuclear weapons.

Medical and academic institutions use molybdenum/technetium generators as a source of Tc-99m for diagnostic tests or research. In this case, the nuclear reactor provides the radioactive parent, molybdenum-99, for the technetium generator. Molybdenum-99 has a short (66 hour) half-life, and decays to the even shorter-lived (6 hrs) Tc-99m…
[With MRI, Ultrasound, Doppler ultrasound, the use of radionuclides in medicine should be obsolete. The only use of ionizing radiation, which appears warranted is x-rays for broken bones. An x-ray machine does not need radionuclides. The short half-life of Tc 99m is discussed, whereas the fact that it becomes Tc 99 with a half-life of 212,000 years is not. While to their credit, and in contrast to the nuclear industry, nuclear medicine has tried to reduce exposure, the use of radionuclides appears completely, or almost completely unneeded. It just serves to provide an excuse for the massive radioactive waste from the nuclear industry. They love to speak of medical and radioactive waste, instead of nuclear waste.]

Technetium-99 has a radioactive half-life of 212,000 years. Technetium-99m (called metastable Tc-99) has a half-life of only about 6 hours and decays to Tc-99 primarily by gamma emission. Technetium-99 decays to form ruthenium-99, which is stable, by emitting beta and gamma radiation.http://www.epa.gov/radiation/radionuclides/technetium.html

It is not benign: “Diagnostic treatment involving technetium-99m will result in radiation exposure to technicians, patients, and passers-by. Typical quantities of technetium administered for immunoscintigraphy tests, such as SPECT tests, range from 400 to 1,100 MBq (11 to 30 mCi) (millicurie or mCi; and Mega-Becquerel or MBq) for adults.[64][65] These doses result in radiation exposures to the patient around 10 mSv (1000 mrem), the equivalent of about 500 chest X-ray exposures.[66] This level of radiation exposure carries a 1 in 1000 lifetime risk of developing a solid cancer or leukemia in the patient.[67] The risk is higher in younger patients, and lower in older ones.[68] Unlike a chest x-ray, the radiation source is inside the patient and will be carried around for a few days, exposing others to second-hand radiation. A spouse who stays constantly by the side of the patient through this time might receive one thousandth of patient’s radiation dose this way.http://en.wikipedia.org/wiki/Technetium-99m Note that the BEIR, 2006, report concurs. 100 mSv carries a 1 in 100 chance of life-shortening cancer and thus 10 mSv carries 1 in 1000.

The US EPA continues:
Technetium-99 is found in the radioactive wastes from defense-related government facilities, nuclear reactor and fuel cycle facilities, academic institutions, hospitals, and research establishments.
….
Most Tc-99 in the environment comes from a few sources:

the detonation of nuclear weapons (especially atmospheric weapons tests)
nuclear reactor airborne emissions
nuclear fuel reprocessing plant airborne emissions
facilities that treat or store radioactive waste.
Extremely small amounts of Tc-99 have entered the environment near a few radioactive waste disposal sites.

How does technetium-99 change in the environment?

Given its long half-life, 212,000 years, Tc-99 remains in the environment. Air, sea water, soils, plants, and animals contain very low concentrations of Tc-99. Organic matter in soils and sediments slows the transport of Tc-99.

In the presence of oxygen, plants readily take up technetium compounds from the soils. Some plants such as brown algae living in seawater are able to concentrate Tc-99. Technetium-99 can also transfer from seawater to animals.

How are people exposed to technetium-99?

Tiny amounts of Tc-99 are part of the environment, and are therefore found in food and water. Higher amounts may be found close to contaminated facilities such as federal weapons facilities or nuclear fuel cycle facilities.

How does technetium-99 get into the body?

Ingestion is the primary entry route for Tc-99 into the body. This may occur by eating food or drinking water contaminated with Tc-99.

What does Technetium-99 do once it gets into the body?

Once in the human body, Tc-99 concentrates in the thyroid gland and the gastrointestinal tract. The body, however, excretes half of the ingested Tc-99 within 60 hours.” [which then goes into the sewers to be ingested by someone or something else or on land as sewer sludge. it goes nowhere]. “It continues to excrete half of the remaining Tc-99 every 60 hours that follow. After 120 hours, only one-fourth of the ingested Tc-99 remains in the body. Nearly all of ingested technetium will be excreted from the body within a month.

Health Effects of Technetium-99
How can technetium-99 affect people’s health?

As with any radioactive material, there is an increased chance that cancer or other adverse health effects can result from exposure to radioactivity.

Because of the large quantity of spent nuclear fuel and defense high-level waste, Tc-99 is one of the more important radionuclides considered.http://www.epa.gov/radiation/radionuclides/technetium.html
[They then give their song and dance that they protect, but this is false. Their standards are also based on concentration and drinking water standards, and the supposition that radionuclides disappear with the wind and flow downstream. Thus, they are someone else’s problem, but they are still there. Dilute and disperse, dilute and deceive is the mantra of the US NRC and the US EPA. The US FDA doesn’t even care – they are ok with people eating enough radiation to give 1% or more chance of cancer in only a few years = 15 x more than allowed in Japan.]

Many medical practitioners are however unaware of the fact that when the Tc-99m disintegrates, it turns into another radioactive materials known as technetium 99 (Tc-99, without the “m”) which gives off beta radiation but no gamma radiation, and which has a half-life of 210,000 years. Since the beta particles are undetectable outside the patient’s body — they do not have sufficient penetrating power — the medical practitioners make no note of the presence of this long-lived radioactive residue. Nevertheless, such “pure beta-emitters” (giving off no gamma rays) can be very damaging to living cells inside the body. Examples of pure beta-emitters that pose serious biological dangers are strontium-90, tritium, and carbon-14.” See this and much more of interest here: http://www.nuclearfreeplanet.org/blogs/waste-transport-dangers-what-is-going-from-chalk-river-to-savannah-river-site.html

Norwegians were unhappy that the UK was dumping technetium into the Irish Sea, which then went to Norway. They still are dumping radionuclides, although in smaller quantity. The reason? It was too dangerous to store in the UK!
Ms Rudjord insists that if it is too dangerous to store technetium-99 on land then it is also too dangerous to pour it into the sea.“, Tuesday, 22 April, 2003, 08:58 GMT 09:58 UK, in “Fishermen vent anger at nuclear waste“, By Jorn Madslien , BBC News Online business reporter in Lofoten, Norway (read the article here: http://news.bbc.co.uk/2/hi/business/2941073.stm_

Sellafield’s liquid radioactive waste is stored in an onshore holding tank. Until last spring, the contents of the tank—which were cleansed of almost all toxic substances except for Tc-99—were being slowly dumped by portions into the Irish Sea three times a year, with the goal of emptying the tank completely by 2007.http://bellona.ru/bellona.org/english_import_area/energy/nuclear/sellafield/33433

Neptunium 237

Neptunium is radioactive, pyrophoric, and can accumulate in bones, which makes handling it dangerous. Neptunium-237, is a by-product of nuclear reactors and plutonium production. 237 Np has a half-life of 2.14 million years. “Finely divided neptunium metal presents a fire hazard because neptunium is pyrophoric; small grains will ignite spontaneously in air at room temperature” Americium 241 has a half-life of 432 years and after 20 years is about 3% neptunium, and after 100 years about 15% neptunium. Neptunium 237 is the most mobile actinide which would be present in nuclear waste. It will become a major contributor to the total radiotoxicity in 10,000 years. https://en.wikipedia.org/wiki/Neptunium

Americium 241

Americium-241 is an unstable (radioactive) isotope with a half-life of 432.7 years. As it decays, it releases alpha and gamma radiation and changes into neptunium-237, which is also radioactive. The americium-241 decay chain ends with bismuth-209, a stable (non-radioactive) element.
[…]
People may be directly exposed to gamma radiation from americium-241 by walking on contaminated land. They may also be exposed to both alpha and gamma radiation by breathing in americium contaminated dust, or drinking contaminated water… americium-241 was widely dispersed globally during the testing of nuclear weapons,… very minute amounts of it are found in the soil, plants, and water. Living near a weapons testing or production facility may increase your chance of exposure to americium-241.

How does americium-241 get into the body?

People who live or work near a contaminated site, such as a former weapons production facility, may ingest americium-241 with food and water, or may inhale it as part of resuspended dust.

What does americium-241 do once it gets into the body?

Once in the body, americium-241 tends to concentrate in the bone, liver, and muscle. It can stay in the body for decades and continue to expose the surrounding tissues to radiation, and increase your risk of developing cancer.

When inhaled, some Am-241 remains in the lungs, depending upon the particle size and the chemical form of the americium compound. The chemical forms that dissolve easily may pass into the bloodstream from the lungs. The chemical forms that dissolve less easily tend to remain in the lungs, or are coughed up through the lung’s natural defense system, and swallowed. From the stomach swallowed americium may dissolve and pass into the bloodstream. However, undissolved material passes from the body through the feces.

Health Effects of Americium-241
How can americium-241 affect people’s health?

Americium-241 poses a significant risk if ingested (swallowed) or inhaled. It can stay in the body for decades and continue to expose the surrounding tissues to both alpha and gamma radiation, increasing the risk of developing cancer. Americium-241 also poses a cancer risk to all organs of the body from direct external exposure to its gamma radiation. One source of direct exposure would be contaminated soil.http://www.epa.gov/radiation/radionuclides/americium.html

Plutonium can also be in Depleted Uranium

Plutonium has at least 15 different isotopes, all of which are radioactive. The most common ones are Pu-238, Pu-239, and Pu-240. Pu-238 has a half-life of 87.7 years. Plutonium-239 has a half-life of 24,100, and Pu-240 has a half-life 6,560 years. The isotope Pu-238 gives off useable heat, because of its radioactivity.

[Note that shorter lived Plutonium 241 with a half life of 14 years, becomes dangerous Americium 241, with a half-life of 432 years. This fact is used to trick people, especially when burying so-called “low level” nuclear waste. (It is also what makes MOX fuel go quickly old.) There is nothing low-level about most of this. Plutonium and Americium accumulate in the body with bodily half-lives of 20 to 50 years, meaning it stays a lifetime – especially the shortened life-times they have planned for everyone. The nuclear industry-regulators’ planned 1 mSv per year exposure for the general public, excludes bioaccumulation and excludes accumulation in the environment, and still, over a lifetime, leads to life-shortening cancers in around 1% of the population, according to the US Gov funded BEIR, 2006, report. The average number of years life is shortened is 14 to 15 according to BEIR. US life expectancy is 78.8 yrs. Thus, there will be no life after retirement. On the other hand, someone will have to pay for costly cancer treatment, etc, unless the US finishes going the way of the Nazis and kills the terminally ill.]

[…]
How do people come in contact with plutonium?

Residual plutonium from atmospheric nuclear weapons testing is dispersed widely in the environment. As a result, virtually everyone comes into contact with extremely small amounts of plutonium.

People who live near nuclear weapons production or testing sites may have increased exposure to plutonium, primarily through particles in the air, but possibly from water as well. Plants growing in contaminated soil can absorb small amounts of plutonium.” [Plutonium mimics iron in the environment and body.]

How does plutonium get into the body?

People may inhale plutonium as a contaminant in dust. It can also be ingested with food or water. Most people have extremely low ingestion and inhalation of plutonium. However, people who live near government weapons production or testing facilities may have increased exposure.

What does plutonium do once it gets into the body?

The stomach does not absorb plutonium very well, and most plutonium swallowed with food or water passes from the body through the feces.” [Thus polluting sewer systems, water, food, and environment].

When inhaled, plutonium can remain in the lungs depending upon its particle size and how well the particular chemical form dissolves. The chemical forms that dissolve less easily may lodge in the lungs or move out with phlegm, and either be swallowed or spit out. But, the lungs may absorb chemical forms that dissolve more easily and pass them into the bloodstream.

Once in the bloodstream, plutonium moves throughout the body and into the bones, liver, or other body organs. Plutonium that reaches body organs generally stays in the body for decades and continues to expose the surrounding tissue to radiation. http://www.epa.gov/radiation/radionuclides/plutonium.html
[But, the US NRC and nuclear industry want people to believe that this is “low level” waste simply because it is a bit diluted with dirt and other things!

About Uranium-Depleted Uranium by the US CDC:
… Everyone is exposed to low amounts of uranium through food, water, and air. Exposure to high levels of natural or depleted uranium can cause kidney disease.” [which, in turn, can cause circulatory disease]. “Uranium has been found in at least 67 of 1,699 National Priorities List sites identified by the Environmental Protection Agency (EPA).
[…]

Uranium is almost as hard as steel and much denser than lead. Natural uranium is used to make enriched uranium; depleted uranium is the leftover product. Enriched uranium is used to make fuel for nuclear power plants. Depleted uranium is used as a counterbalance on helicopters rotors and airplane control surfaces, as a shield to protect against ionizing radiation, as a component of munitions to help them penetrate enemy armored vehicles, and as armor in some parts of military vehicles.” [It has been studied as shielding for nuclear waste, which is the only place it should be used. It could replace lead, if plutonium, etc., could be removed.]

What happens to uranium when it enters the environment?

Natural and depleted uranium that exist in the dust in the air settle onto water, land, and plants. Uranium deposited on land can be reincorporated into soil, washed into surface water, or stick to plant roots. Uranium in air, surface water, or groundwater can be transported large distances.

How might I be exposed to uranium?

Food and drinking water are the primary sources of intake for the general public. Very low levels of uranium are found in the air.

Root crops such as potatoes, parsnips, turnips, and sweet potatoes contribute the highest amounts of uranium to the diet. Because uranium in soil can stick to these vegetables, the concentrations in these foods are directly related to the concentrations of uranium in the soil where the foods are grown.” [Thus, the EU allows higher radiation levels in root crops in the event of a nuclear accident, even though potatoes are staple crops in many Euro countries. The same is true of chocolate and coffee, which get classified as non-foods, so that more radiation is allowed.]

In most areas of the United States, low levels of uranium are found in the drinking water. Higher levels may be found in areas with elevated levels of naturally occurring uranium in rocks and soil.” [In some parts of the US (e.g. in Illinois), uranium sludge cleaned from water, under the clean water act, is applied to fields, which just shifts it from drinking water to food and groundwater.]

People may be exposed to higher levels of uranium if they live near uranium mining, processing, and manufacturing facilities. People may also be exposed if they live near areas where depleted uranium weapons are used.

How can uranium enter and leave my body?

Most of the uranium you breathe or ingest is not absorbed and leaves the body in the feces.” [adding to the burden of the sewer system; environment.] “Absorbed uranium is deposited throughout the body. The highest levels are found in the bones, liver, and kidneys; 66% of the uranium in the body is found in your bones. It can remain in the bones for a long time; the half-life of uranium in bones is 70-200 days. Most of the uranium that is not in bones leaves the body in the urine in 1-2 weeks.

How can uranium affect my health?

Natural uranium and depleted uranium have the identical chemical effect on your body.

Kidney damage has been seen in humans and animals after inhaling or ingesting uranium compounds. However, kidney damage has not been consistently” [note use of word “consistently”, which means it has been found sometimes.] “found in soldiers who have had uranium metal fragments in their bodies for several years. Ingesting water-soluble uranium compounds will result in kidney effects at lower doses than following exposure to insoluble uranium compounds.

Studies in animals have shown that inhalation exposure to insoluble uranium compounds can result in lung damage. In male rats and mice, exposure to uranium has been shown to decrease fertility. Uranium compounds on the skin caused skin irritation and mild skin damage in animals.

Health effects of natural and depleted uranium are due to chemical effects and not to radiation.

How likely is uranium to cause cancer?

Neither the National Toxicology Program (NTP), the International Agency for Research on Cancer (IARC) nor the EPA have classified natural uranium or depleted uranium with respect to carcinogenicity.

How can uranium affect children?

The health effects seen in children from exposure to toxic levels of uranium are expected to be similar to the effects seen in adults.

Exposure of animals to high levels of uranium during pregnancy, which caused toxicity in the mothers, has induced early deaths and birth defects in the young. It is not clear if this can happen in the absence of effects on the mother… There are some studies that suggest that exposure to depleted uranium increased the frequency of birth defects,…

How can families reduce the risk of exposure to uranium?

Avoid eating root vegetables grown in soils with high levels of uranium. Consider washing fruits and vegetables grown in that soil and discard the outside portion of root vegetables.” [But, they put uranium sludge and contaminated sewer sludge on food in many places. Translation: Don’t eat; die of starvation before kidney damage and cancer?]

Consider having your water tested if you suspect that your drinking water might have elevated levels of uranium; if elevated levels are found, consider using bottled water.
[Which may also have radionuclides in it and will increasingly have them.]

Is there a medical test to show whether I have been exposed to uranium?

… there will always be some level of uranium in all parts of your body. If depleted uranium is present, it adds to the total uranium level. Uranium can be measured in blood, urine, hair, and body tissues. Most tests are for total uranium; however, expensive tests are available to estimate the amounts of both natural and depleted uranium that are present.

Has the federal government made recommendations to protect human health?

The government has made recommendations for uranium which apply to natural and depleted uranium combined.

The EPA established a maximum drinking water contaminant level of 0.03 mg/L.

The Occupational Safety and Health Administration has limited workers’ exposure in air to an average of 0.05 mg U/m3 for soluble uranium and 0.25 mg U/m3 for insoluble uranium over an 8-hour workday.

The National Institute for Occupational Safety and Health recommends workers exposure be limited to 0.05 mg U/m3 of air for soluble uranium and 0.2 mg U/m3 for insoluble uranium averaged over a 10-hour workday and recommends that exposure to soluble uranium not exceed 0.6 mg U/m3 for more than 15 minutes.

The Nuclear Regulatory Commission has established air concentration limits for uranium and its individual isotopes that apply to occupational exposure and releases from facilities. Source of Information
Agency for Toxic Substances and Disease Registry (ATSDR). 2013. Toxicological Profile for Uranium. Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service.

http://www.atsdr.cdc.gov/toxfaqs/tf.asp?id=439&tid=77

Existing NRC regulations at 10 CFR 61.55, “Waste Classification,” specify criteria for determining the classification of low-level radioactive waste for land disposal at a near-surface facility. The original development of 10 CFR 61.55 did not explicitly consider the impacts resulting from the disposal of unique waste streams such as significant quantities of depleted uranium from the operation of a commercial uranium enrichment facility. When 10 CFR Part 61, “Licensing Requirements for Land Disposal of Radioactive Waste,” was initially developed, there were no commercial facilities generating significant quantities of depleted uranium waste streams. As a result the analysis only considered the types of uranium-bearing waste streams being typically disposed of by licensees at the time. Additionally, the nature of the radiological hazards associated with DU presents challenges to the estimation of long-term effects from its disposal – namely that its radiological hazard gradually increases due to the ingrowth of decay products, eventually peaking after 1 million years, rather than decreasing significantly over a few hundred years like that of typical LLW.

[This is false. So-called LLW includes very long-lived radionuclides, such as plutonium and americium, which remain radioactive for thousands of years. Iodine 129 remains radioactive for millions of years.]

The U.S. Nuclear Regulatory Commission (NRC) staff has identified several key issues for initial discussion with stakeholders on disposal of DU. These include defining key regulatory terms such as unique waste streams and significant quantities of depleted uranium as well as technical parameters of a site-specific analysis including a time period of performance, appropriate exposure scenarios for protection of the public and individuals from inadvertent intrusion. The NRC staff is also soliciting stakeholder views on technical issues for a site-specific analysis of near-surface disposal of significant quantities of depleted uranium. These technical issues include appropriate considerations for depleted uranium waste form(s), uranium geochemistry, and radon migration and exposure. These issues arose from the results of the NRC staff’s technical analysis (SECY-08-0147) that was submitted to the Commission on October 7, 2008, in response to Commission Order CLI-05-20 regarding depleted uranium. Given those issues, the Commission’s related Staff Requirements Memorandum (SRM-SECY-08-0147), dated March 18, 2009, instructed the staff to begin engagement with stakeholders and interested parties to initiate development of the technical basis for possible revision of the 10 CFR Part 61, “Licensing Requirements for Land Disposal of Radioactive Waste.” Toward that end, the staff has scheduled public workshops to discuss the benefits and impacts of revising 10 CFR Part 61. In so doing, the staff hopes to identify potential conflicts and gain an understanding of any unintended consequences that may result from drafting and implementing related changes to the NRC’s existing regulations.
http://www.nrc.gov/about-nrc/regulatory/rulemaking/potential-rulemaking/uw-streams/bg-info-du.html

Note 1: French journalist Jean-Baptiste Renaud spent 6 months researching France’s (EDF-Areva) nuclear policy of lies. The investigation “Nucleaire la politique du mensonge” aired first on Canal Plus, and Special Investigation put it on their youtube channel at the end of May: http://youtu.be/LDOH9AN_E3s
At 31 min 49 sec he explains that enriching uranium makes a lot of waste. For each kg of enriched uranium, there is 7 kg of depleted uranium produced. In Bessines sur Gartempe, Haute-Vienne, France, Antoine Gatet of the local Association “Sources et Rivieres du Limousin” points out the depleted uranium stored in metal sheds, of the sort used in agriculture – essentially large barns. It has been there for at least 20 years, maybe 30. (At one point they mention that it’s been there 20 and then they speak of 30. It was probably someplace else for the first 10.).