Plutonium

Plutonium

Deadly environmental pollution has become an existential risk that threatens the prospect not just for human immortality, but for the long-term survival of our species and a great many others. Here we will focus on the nuclear waste aspect of the problem and ways to mitigate it before there is a critical tipping point in our global ecosystem. As philosopher Nick Bostrom said in his 2001 paper titled “Existential Risks,” published in the Journal of Evolution and Technology, “Our future, and whether we will have a future at all, may well be determined by how we deal with these challenges.”1

Unlike many radioactive materials that degrade fairly rapidly, some will remain intensely poisonous for incredibly long periods. Plutonium-240 (Pu-240) has a half-life of 6,560 years. The half-life is the time it takes for radioactive decay to decrease by half. But decay does not occur at an even pace, and radioactive isotopes are dangerous for much longer – typically 10 to 20 times the length of their half-life. Pu-238 has an 88-year half-life, and is used for space vehicles despite the frequency of rocket failures. Any exploding rocket including such cargo spreads pollution far and wide. Pu-239 has a half-life of over 24,000 years, and will remain radioactive for about a half a million years. But the situation is more complicated because as Pu-239 decays it transforms to uranium-235 (U-235), which has a half life of 600 to 700 million years. Iodine-129 has a half-life of 16 million years. Pu-244 has a half-life of 80.8 million years. U-238 has a half-life of 4.5 billion years.2

When taken into the body, isotopes of radioactive plutonium are not fully eliminated and tend to accumulate. They are deadly when sufficiently accumulated. Pu-239 was described by its co-discoverer, chemist Glenn Seaborg, as “fiendishly toxic.” In addition to terrible chemical toxicity, plutonium emits ionizing radiation. Pu-239 emits alpha, beta and gamma particles. Gamma radiation can penetrate the entire body and kill cells. Pu-239 has a robust resonance energy of 0.2 96 electron-volts that can badly damage DNA and produce birth defects that carry over generations.3 The body repairs tissues and DNA, but becomes overwhelmed when plutonium concentrates too heavily.

According to a 1975 article in New Scientist Magazine, “But if it is inhaled, 10 micrograms of plutonium-239 is likely to cause fatal lung cancer.”4 Experts estimate that Pu-239 is so noxious that only one pound would be enough to kill everyone on our planet if it were so evenly dispersed in the air that everyone inhaled it.5

Although it occurs in nature in exploding stars, almost all plutonium on Earth is man-made – the product of manufacturing nuclear weapons and energy in nuclear power plants. Of the different forms of nuclear products, deadly Pu-239 is very abundant because it is used to make nuclear weapons and is a by-product of energy production in nuclear reactors. As part of the U.S. weapons program (between 1944 and 1988), 114 tons of Pu-239 was produced in nuclear reactors at the Hanford Works facility, in Washington state, and at the Savannah River Site in South Carolina.6 Large quantities of this u-239 remains at temporary storage facilities at these locations. Hanford stores about 50 million gallons of high-level radioactive nuclear and chemically hazardous wastes in underground storage tanks that were not designed for long-term storage. Roughly a third of these tanks have leaked, so that at least a million gallons of radioactive waste has reached the natural environment. Hanford is the most toxic site in the U.S., and among the most toxic places on Earth. Over 1,000 contaminated sites at Hanford have been identified. Groundwater aquifers are polluted for over 200 square miles beyond Hanford.

No less than nine pounds of Pu-239 is used to make a working nuclear bomb. As of 2015, a total of 15,695 nuclear weapons are stockpiled by nine countries.7 Some of these weapons are 35 years old, but have a shelf-life of only 25 years.8 These aging weapons are undergoing corrosion. oxidation and other detrimental changes, and they must constantly be maintained and upgraded to prevent them from becoming an immanent threat to life on Earth. They are primary war targets. The situation emphasizes the need for absolute global peace.

As of 2014, about 435 nuclear power plants have been built in 31 countries around the world.9 A great number of radioactive products, including Pu-239, are byproducts of U-235 fission occurring in the fuel rods of those plants with uranium reactors. In addition to being susceptible to natural disasters and accidents, these nuclear plants are all vulnerable to acts of war. They, too, emphasize the need for absolute global peace.

Many nuclear power plants are operating beyond their established service lives, and storing their nuclear wastes remains highly problematic. No method for the long-term storage of high-level nuclear products was available when industries began producing them to make commercial energy and weapons. Storage remains very precarious, and there is no realistic way to safeguard those that are long-lived. There are 93 different long-lived radioactive elements that are toxic for a minimum of 17,000 years, and the time scale extends for many billions of years of total decay time for some.10

The U.S. alone stores tens of thousands of tons of spent fuel containing Pu-239 and other highly radioactive materials from the various reactor cores. The quantity continues to increase worldwide as long as the nuclear plants continue to operate. About 1% of spent nuclear fuel is plutonium, and nuclear power provides about 10 percent of the world’s electricity. A uranium reactor will contain about a ton of plutonium. These figures provide a rough idea of the enormity of continual global radioactive waste accumulation. Aside from accidents like the Chernobyl disaster (which contaminated 40% of Europe), dangers include the potential for spontaneous fuel combustion and nuclear meltdown at pools containing spent fuel. The following quote from a National Research Council Panel report provides a rough idea of the growing tonnage build-up of plutonium from commercial nuclear reactors:

“New production of commercial reactor plutonium during the first half of the 1990s was about 70 MT [metric tons] per year.”11

At least four to five tons of Pu-239 are known to have been released into the environment during nuclear weapons testing.12 Much of the Pu-239 remains buried underground at the test sites. But some was released into the air during atmospheric tests, and some traveled for many miles by way of groundwater after underground tests. About two-thirds of the plutonium in the atmosphere winds up in the oceans, where it tends to sink to their bottoms and challenges sea life. The polluted sediment is disturbed and redistributed by underwater tsunamis, earthquakes, volcanoes and enormous landslides.

According to the U.S. Environmental Protection Agency (EPA):

“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.”13

The EPA adds:

“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.”

Given that humans retain plutonium, the longer we live the more of it our bodies can accumulate. Although exposure can vary widely because of the way plutonium becomes distributed in the environment, it is has already reached high enough levels globally to cause serious concern: According to a report from the Proceedings of the NATO Advanced Research Workshop of the year 2000, titled High-Sensitive Determinations of Pu and Am Content in Human Tissues:

“Now plutonium of both industrial and weapon origin is widely spread all over the world and included in the soil cycle, water cycle and the food chain, the end point of which is a human body….Now we warn about the serious hazard of dangerous accumulation of plutonium and americium in human body, especially in liver and bones….As it has been established recently, plutonium in its tetravalent state (TV+) is accumulated in human body during the whole life…”14

Since that report was published, additional plutonium isotopes have been added to our body burden. High levels of Pu-239 were released after the magnitude 9.0 Tōhoku earthquake and tsunami of March 11, 2011 triggered the disaster at Japan’s Fukushima Daiichi power plant. The initial venting from containment vessels into the atmosphere, the meltdown (and melt through) of three of the facility’s nuclear reactor cores, and the continual release of contaminated coolant water into the Pacific Ocean are parts and parcels of the most lethal nuclear accident to date.

After the radioactive plume from Fukuskima began circulating the Earth every 40 days or so (depositing over 1,000 different types of toxic substances on land and in water with each pass), plutonium was measured in the Pacific Ocean and its sea life, and in many U.S. cities and far beyond. A news headline from 2011 reads, “Report: 76 trillion becquerels of Plutonium-239 released from Fukushima — 23,000 times higher than previously announced.”15 The initial radioactive plume was discharged into both the air and water, and the water portion of the plume is expected to reach the U.S. coast along ocean currents by 2017. Smaller plumes continue to be generated as radioactive water is poured directly into the ocean each day. It remains to be seen how much all of this will affect marine life and the food chain along the U.S. west coast. California produces most of the fruits and vegetables for the rest of the country. The rule of thumb is that small particulates move along ocean currents, and large particulates sink to the marine sediments.

Since the accident, 300 to 400 tons of radioactive water from the Fukushima nuclear complex have been pouring into the ocean every day 16 In 2014, Tokyo Electric Power Company (TEPCO), in charge of the cleanup operation, began filtering 62 (out of over 1,000) radioactive isotopes from the millions of gallons going into the sea – and creating water plume after plume crossing the ocean.17 The myriad of resulting toxic water filters, which deteriorate due to radiation exposure, will require permanent storage.

The public receives conflicting information about whether plutonium will be brought under control. A 2014 headline reads, “Tepco NOT to analyze Plutonium or Uranium in bypass water before discharging to the Pacific.”18 Another report says that plutonium is among the treated radioactive contaminants.19 Another says that the volume or output of the radioactive materials that are filtered out will be reduced by 90%.20 This can suggest that each day 90% less plutonium and certain other harmful radioactive toxins will flow into the sea than before.

A 2015 report says, “Expert: “It’s completely unsafe… impossible to remove 100s of radioactive materials” – 1,200 radionuclides, only 62 reduced.” “It’s impossible for them to remove all those hundreds of radioactive materials. They know how to remove about 62 of them, but there’s other ones that they cannot.”21

A headline from 2015 reads: “Experts: Plutonium levels 10,000,000 times normal in water below Fukushima reactors – Plutonium hit record high off coast in 2014 – “Has been transported relatively long distances” – Every sample taken from rivers flowing into Pacific had Pu-239, Pu-240, Pu-241,and Pu-242 from plant.” “…the amount of Pu isotopes directly released into the marine environment remains unknown.” The total oceanic burden is difficult to accurately estimate by taking surface or near-surface samples from flowing ocean water.22

Since it is presently impossible to know how much plutonium has or will be released into the ocean, and since so many conflicting opinions appear in the news, we can make rough estimates based on how much was in the reactor cores in the first place. According to nuclear engineer Arnie Gundersen: “A ton of plutonium was in each Fukushima reactor.”23 Three 100-ton reactor cores melted down, and a fourth is badly damaged. Of the three melted reactors, after they underwent meltdown nuclear fuel penetrated their containment vessels and melted into the ground below (a process termed ‘melt through’). Then an unprecedented event (called ‘melt out’) occurred, so that the locations of the reactor cores is unknown.

Some experts think that the mysterious highly radioactive black particulate deposited all over Fukushima, Tokyo and other parts of Japan includes the remnants of these lost cores. In theory, during the meltdowns the cores exploded with sufficient force to scatter as the black particulate (containing dangerous hot particles and other radioactive materials). This black substance matches, as best as can be determined, with components of core fuel and may include vaporized cores.24 Pu-239 and many other types of ionizing radiation are produced in reactor cores. The black particulate gradually breaks down into smaller particles, soaks into the ground and is scattered into the wind and water.

The cleanup at Fukushima is expected to take four decades, and there is no telling how far into the future highly-contaminated water will continue to pour into the ocean. It will only be stopped under certain conditions: There must be a means of preventing groundwater from entering the reactor buildings (through the basements and failed seals), so that the contaminated coolant water stops blending with the freshwater flowing in and out of the structures. The other condition is that the reactor buildings finally sufficiently cool so that coolant water is no longer required. Four reactor buildings are being cooled by water to prevent dangerous heat build-up that can cause another explosion. So, water is constantly being poured onto the premises and becomes laced with radioactive materials, and then it is partially filtered and put directly into the ocean.

So far, humans cannot go near the melted Fukushima reactors for an hour without being exposed to lethal amounts of radiation poisoning. Robots are the only alternative for performing work. But high-level radiation quickly causes electronics components to malfunction and fail within minutes. In April of 2015, the second robot developed to work within a damaged reactor was abandoned after it failed.25 A new robotic attempt is being planned for next year.

The potential for typhoons, flash floods, earthquakes and tsunamis place the damaged reactor buildings at Fukushima in further jeopardy. At least one tsunami will typically hit some part of Japan every year, which is far lower than the country’s frequency of earthquakes.

Even if plutonium is brought under better control, the other nuclear contaminants being released from Fukushima, the on-going low level radioactive releases permitted around the world at uranium mines and mills, fuel fabrication plants, storage pools, casks, and trenches, etc. accumulate in the environment. Too much body burden brings on birth defects in newborns. Many Iraqi children born after depleted uranium weaponry was used during the Gulf War suffer hideous deformities. Irresponsible radioactive waste disposal is suspected of causing the significant cancer rise in southern Italy.

Five reactors in the U.S. are known to be built in earthquake zones, too.26 New earthquake faults that threaten Hanford have been discovered since it was built. In 2015, Michigan quakes initially left scientists puzzled. The situation resulted in the identification of a previously unconfirmed earthquake fault line.27 Earthquake frequency has increased dramatically in the U.S. over the past few decades, and the frequency rate has continued to increase. Tornadoes are also a threat to the safety of nuclear plants, and the Fermi 2 reactor, located between Detroit and Toledo, experienced a near miss when a tornado ran directly through two of its cooling towers in 2014.

Some physicists assert that humanity will always be plagued by the consequences of the Fukushima disaster.28 Scientists who study the ocean floor report a huge spike in unexplained sea life die-offs.29 Many thousands of tons of radioactive materials have been dumped into the Atlantic, too. The oceans are getting warmer and steadily more acidic, and oxygen is depleting at an increased pace. The entire oceanic ecosystem is threatened by over 70,000 types of pollution, and human CO2 emissions (mostly from fossil fuel combustion, transportation and industrial processes) are usually considered largely to blame.30 There are over 500 large oceanic dead zones, areas in which the oxygen concentration is so low that sea life suffocates. Science cannot predict the ultimate consequences of the changes in our oceans, but mass extinction of ocean life is predicted.31 No wonder some news sources are sounding alarm bells about the potential death of the Pacific Ocean.32 Oceans play a leading role in Earth’s overall climate, and they heavily impact the weather patterns on land. Humankind is not presently set up to endure drastic changes in climate or weather.

Solutions for Trying to Militate the Problems:

Aside from reducing greenhouse gases and balancing their levels in the atmosphere, fortifying our health as much as possible, creating better filtration systems that can gradually capture environmental pollutants of all kinds, and reducing and eliminating the release of dangerous pollutants, a number of less obvious steps can be taken to mitigate the problems described:

Diamond Film Microcircuitry:
Robots will be required to contend with the Fukushima crisis. At the very least, they should be able to seal the buildings to stop the contaminated water leakage. But they are not capable of doing such manual work because their electronics fry in minutes when exposed to the intense hard radiation. In previous articles, I have explained the superiority of electronics and computerized robotics based on Diamond Film Microcircuitry (DMF), made with single crystal diamond film. The links below lead to articles about DMF, including how it is made and why it is superior to conventional electronics and robotics:

http://transhumanity.net/advantages-of-dmf-optical-computing-over-the-d-wave-quantum-computing-opinion/

http://transhumanity.net/ushering-in-the-diamond-age-of-quantum-computing/

In addition to the performance of DMF discussed in the above-linked articles, synthetic diamond is used to make corrosion-hard particle radiation detectors. Diamond will tolerate being directly immersed in Pu-239 diluted in concentrated nitric acid, and it will reliably measure alpha activity.

While 2015 predictions of radiation emissions from Fukushima are not yet available, measurements from 2011 showed a release of 3696 megarads per week:33 Whereas, diamonds routinely take exposures of up to 8000 megarads during color enhancement treatments. During color enhancement, diamonds are subjected to proton bombardment in cyclotrons. The gemstone will tolerate a tremendous amount of high-energy particle radiation of various types, too. Diamonds are subjected to neutron bombardment in nuclear reactors. They are exposed to high electron bombardment by Van de Graaff generators. These very high-energy processes are what it takes to knock carbon atoms out of place in a diamond’s crystal lattice. Diamonds remain in high energy fields for 1,000 hours or more during color enhancement. Diamond naturally acts as a heat spreader, too, and so can be used to help stabilize temperatures in reactors and cool cores faster. Given diamond’s proven properties, there is every reason to expect high performance from robots, computers and other electronic devices made of DMF.

DMF contains three-dimensional internal channels made of graphite, created to carry electricity through devices (such as sensors, robotics, computers, etc.). Graphite shows no degradation when exposed to 1,000 megarads (compare the 22 megrads per hour emitted in Fukushima’s Reactor 2), and in DMF graphite is protected by diamond that can stand even higher radiation levels. Forms of graphite are used in the first wall of the UK’s Joint European Torus, a leading fusion experiment facility. Graphite has ideal thermal and electrical properties. It has an even higher melting point than diamond (the latter of which is 6,420 °F when subjected to high pressure). The use of DMF would be a wise choice for developing robotics that can operate within high-level hard radiation environments.

Geopolymerized Rock:
Ultimately, the Fukushima buildings will be entombed like the Chernobyl nuclear reactor that exploded in 1986. But despite being entombed in 5,000 tons of concrete, Chernobyl has continuously leaked radioactive materials into the environment. These materials are pulled from local soil by trees and other plants through their root systems. This is happening because the Chernobyl reactor is entombed in ordinary Portland cement based concrete, which is inadequate for keeping toxins immobilized. The entombment structure must be frequently repaired to protect the environment.

All of the hundreds of nuclear reactors around the world must ultimately be either dismantled (a very expensive and dangerous process) or else safely entombed after they reach the end of their service lives. Successful remediation that does not leak requires that the entombment structures tolerate freeze thaw cycles and the hydrothermal conditions created when groundwater from rain, snow or floodwaters reaches hot reactors. Every reactor that is shut down to an inactive state continues to generate a significant amount of residual heat. When water comes into contact with the hot reactors, very hot water is produced that will degrade a Portland cement concrete entombment. The result of such containment is either very prolonged environmental contamination or else very prolonged, expensive maintenance.

Geopolymerized rock (geopolymeric concrete) tolerates both hydrothermal conditions and freeze thaw cycles. It is made purely of minerals (which have a high heat tolerance) that are molecularly bound, without using heat or intense presume, to form rock-concrete. The geopolymeric binder is equivalent to silicates that make up over 55% of the Earth’s crust. The Battelle Institute, in Germany, tested geopolymerization for the European high-level nuclear waste classification. The Battelle researchers determined geopolymerization to be a “valuable alternative” to present day vitrification technologies.34 Geopolymers have excellent engineering properties. It would be wise for countries with nuclear reactors to test geopolymers for their particular radioactive waste needs, especially entombment.

Geopolymers and DMF work well together, and are the key components of the GEO-DMF System. A well-made geopolymer entombment can be expected to endure for thousands of years, during which time it would not be degraded by acid rain, salt or other environmental corrosives. DMF sensors and other devices can be built into reactor entombments to monitor internal conditions and maintenance needs. Although not a total solution to the nuclear waste problems plaguing our planet, rock-solid geopolymeric containment coupled with a dependable, automated and enduring monitoring system would be a vast improvement over the present means of securing nuclear wastes and weapons arsenals.

Both geopolymers and synthetic diamond film DMF are impervious to water, which means that flooded buildings made with geopolymeric building blocks and DMF electronics will be as good as new when they dry out. DMF electronics (three-dimensional graphite zones) are encased within the synthetic diamond film. Geopolymerized rock (rock aggregates bound by a geopolymeric binder) can be molded into multi-ton megalithic building blocks that will allow structures to withstand the strongest known hurricane winds. The GEO-DMF System can provide for fireproof, weatherproof housing and other buildings, and help fortify coastal cities against sea level rise. Wise utilization of these technologies would allow humankind to better deal with existential and more localized risks while ushering in mature phases of the coming technological revolution.

Margaret Morris
GEO-DMF System
Contact: matmargaretmorrisbooksdotcom

Endnotes:

1. http://www.nickbostrom.com/existential/risks.html

2. https://en.wikipedia.org/wiki/Isotopes_of_plutonium

3. Management and Disposition of Excess Weapons Plutonium:: Reactor-Related Options Panel on Reactor-Related Options for the Disposition of Excess Weapons Plutonium, National Research Council, Policy and Global Affairs, Office of International Affairs, National Academies Press, Jul 6 (1995), page 351.

4. New Scientist Magazine, Vol. 65, No. 941, Mar 20, 1975, p. 725.

5. Tim Janakos, Collected Writings From Soka University of America, Second American Renaissance Press, Escondido, 2011, p. 54.

6. Michael L. McKinney (ed.), Outlooks: Readings for Environmental Literacy, Second Edition, Jones & Bartlett Learning, London, etc., 2004, p. 89.

7. http://www.ploughshares.org/world-nuclear-stockpile-report

8. https://www.lanl.gov/quarterly/q_w03/shelf_life.shtml

9. John Moore, Conrad Stanitski, Chemistry: The Molecular Science, Fifth Edition, Cengage Learning, 2014, Stamford, CT, p. 807.

10. http://agreenroad.blogspot.com/2012/03/93-long-lived-nuclear-elements.html

11. Panel on Reactor-Related Options for the Disposition of Excess Weapons Plutonium, Office of International Affairs, Policy and Global Affairs, National Research Council, Management and Disposition of Excess Weapons Plutonium: Reactor-Related Options, National Academies Press, 1995, Page 3, note 1.

12. Tim Janakos, Collected Writings From Soka University of America, Second American Renaissance Press, Escondido, 2011, p. 54.

13. http://www.epa.gov/radiation/radionuclides/plutonium.html

14. Yu.T. Chuburkov et al., High-Sensitive Dereminations of Pu and Am Content in Human Tissues, in RadionuKluwer Academic Publishers, Dordrecht (2001), p. 72.

15. http://enenews.com/updated-report-76-trillion-becquerels-plutonium-239-released-fukushima-23000-times-higher-previously-announced

16. Presented by Ecoshock radio, with nuclear engineer Anrie Gundersen as a speaker: ttps://www.youtube.com/watch?v=mCDwByuR_S0

17. http://www.bloomberg.com/news/articles/2014-06-09/tepco-hires-us-company-to-filter-water-stored-in-fukushima-tanks

18. http://fukushima-diary.com/2014/04/tepco-not-to-analyze-plutonium-or-uranium-in-bypass-water-before-discharging-to-the-pacific/

19. http://www.japantimes.co.jp/news/2013/05/21/reference/fukushima-no-1-cant-keep-its-head-above-tainted-water/#.ValFApePW7s

20. http://www.tepco.co.jp/en/press/corp-com/release/2014/1243241_5892.html

21. http://enenews.com/tv-govt-approves-plant-drain-fukushima-nuclear-waste-ocean-fisherman-trust-tepco-expert-completely-unsafe-impossible-remove-all-hundreds-radioactive-materials-video

22. http://enenews.com/experts-plutonium-levels-10000000-times-normal-water-below-fukushima-reactors-plutonium-ocean-japan-hit-record-high-2014-pu-transported-relatively-long-distances-every-sample-rivers-flow-pacific

23. http://enenews.com/gundersen-a-ton-of-plutonium-was-in-each-fukushima-reactor-host-stunned-video

24. http://www.globalresearch.ca/fukushima-didnt-just-suffer-three-meltdowns-the-nuclear-core-has-finally-been-found-scattered-all-over-japan/5379147 )

25. Wall Street Journal Article:
http://enenews.com/cnn-strange-green-glow-inside-fukushima-reactor-reports-yellow-blue-green-other-colors-could-be-video

26. http://usatoday30.usatoday.com/news/nation/2011-04-11-1Anukes11_ST_N.htm

27. http://usatoday30.usatoday.com/news/nation/2011-04-11-1Anukes11_ST_N.htm

28. http://www.globalresearch.ca/physicists-say-fukushima-reactors-pose-eternal-threat-to-humanity/5397537

29. http://thetruthwins.com/archives/fukushima-aftermath-98-percent-of-the-pacific-ocean-floor-covered-by-dead-sea-creatures

30. http://www.unesco.org/new/en/natural-sciences/ioc-oceans/priority-areas/rio-20-ocean/blueprint-for-the-future-we-want/marine-pollution/facts-and-figures-on-marine-pollution/

31. http://www.dailykos.com/story/2013/10/04/1243700/-The-Oceans-are-Dying-Oxygen-is-Depleting-Acidity-Rising-at-Fastest-Rate-in-300-000-000-Years#

32. http://allnewspipeline.com/Pacific_Ocean_Blob_Fukushima.php
http://geroldblog.com/2015/04/11/fukushima-forever-the-pacific-ocean-is-dying/

33. http://www.zerohedge.com/article/japan-nuclear-agency-radiation-level-fukushima-reactor-no-2-its-highest-level-recorded-so-fa

34. Battelle Institut, Germany. Ceramic Transactions, Vol. 36, “Microwaves: Theory and Application in Materials Processing II” (1993), 61–72, Presented at the International Symposium on Microwave Processing, the 95th Annual Meeting of the American Ceramic Society, held in Cincinnati, April 19–22, 1993. Also see A. D. Chervonnyi and N. A. Chervonnaya, “Geopolymeric Agent for Immobilization of Radioactive Ashes after Biomass Burning” Radiochemistry, Vol. 45, Number 2, March (2003), 182-188. The abstract reads, “Solidification of low-level radioactive wastes obtained after biomass burning was studied. Two solidification modes using Portland cement and geopolymeric binder were tested experimentally. The strength at various hardening times, compacting efficiency, and leaching rate of the resulting monolithic concretes were analyzed. The compacting efficiency in concretes prepared by two different modes is similar. At the same time, geopolymeric binder is solidified in significantly shorter period and its compression strength is several times higher, but its main advantage is chemical immobilization of strontium cations. The leaching rate under the static conditions after 28-day hardening is nearly 10- 6 g cm- 2 day- 1. Thus, substitution of geopolymerization of the clay component (in general case, aluminosilicate material) for common solidification of low-level wastes using Portland cement is economically promising due to significant energy and resource saving. The geosynthesis can be easily realized as an environmentally safe process, yielding no liquid waste and involving no high-temperature stages with radioactive
materials.”

Image credit:
U.S. Department of Energy:
http://www.doedigitalarchive.doe.gov/ImageDetailView.cfm?ImageID=2006407&page=search&pageid=thumb