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Radioactivity Neutralization Methods


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Define the Target

Like other industrial processes, generating electricity from nuclear power or making nuclear weapons creates waste. These radioactive and chemically toxic wastes result from the mining and processing of uranium as well as from storing or reprocessing spent reactor fuel.


Waste from Uranium Production

The tailings or waste produced by the extraction or concentration of uranium from its ore contain radioactive isotopes of uranium, thorium, and radium as well as significant concentrations of heavy metal including chromium, lead, molybdenum, and vanadium. More than 200 pounds of tailings are produced for each pound of uranium. This sandy waste material must be contained in carefully monitored sites known as tailings piles – an example of which is shown in Figure 1.


Waste from Conversion, Enrichment, and Fuel Fabrication Processes

Uranium production processes do not affect the level of radioactivity and do not produce significant chemical waste. An enrichment process for one ton of uranium hexafluoride produces 130 kg of UF6 (3.5% U-235) and 870 kg of depleted UF6 containing U-238. Depleted uranium has few applications. However, its high density of 18.7 g/cm3 makes it useful in armor plating and radiation shielding. It is also a potential energy source for fast breeder reactors.




Figure 1 – Containment Site on the Colorado River near Moab, Utah

(Courtesy of WISE Uranium Project)
Waste from Reactors

Spent fuel in the open and closed fuel cycles generates radioactive waste. The components of spent reactor fuel can either be treated as waste (in the open fuel cycle) or reprocessed (in the closed fuel cycle). In either case, spent fuel from the reactor is initially stored in cooling ponds under water at the reactor site to allow a decrease in radioactivity and a corresponding decrease in temperature. The amount of time the spent fuel remains in a pool is determined by whether it is to be kept as waste or reprocessed for either fuel or nuclear weapons.  If it is to be treated as waste, it can remain in the pool indefinitely. If it is to be reprocessed to recover plutonium for weapons, it is removed after several months.


Waste from Nuclear Power Generation – The Open Fuel Cycle

In the open fuel cycle, the spent fuel rods remain in the pools under at least 20 feet of water (Figure 2), which protects the surroundings from radiation.


After a minimum of one year, the rods may be removed from the pool and placed in a cylinder in a chemically inert atmosphere of helium gas (Figure 3). The cylinder is then sealed and encased in steel and concrete to contain the radiation and enhance security for storage or transportation to a permanent repository. In 2008 there were 160,000 assemblies containing 45,000 tons of spent fuel from nuclear power reactors in the United States. The majority of these are stored at the reactor sites in reactor pools with only about 5 percent in dry casks. Each year about 7,800 additional used fuel assemblies are placed into storage. If all of the current assemblies were collected in a single location they would cover a football field to about a height of five and half yards.
Waste from Reprocessing Spent Fuel – The Closed Fuel Cycle

Spent fuel to be reprocessed for mixed oxide (MOX) fuel remains in the pool for several years before removal. The PUREX (link to unit on plutonium production) LINK process, used both for extracting plutonium and uranium in the closed fuel cycle and plutonium for weapons, generates large volumes of chemical and radioactive waste. In addition, the small amount of highly radioactive material remaining in spent reactor fuel after extraction of the uranium and plutonium poses a significant waste management problem.





Figure 2 – Storage of Spent Fuel at the Reactor

(Courtesy of the Union of Concerned Scientists)




Figure 3 – Dry Cast Storage

(Courtesy of the U. S. Nuclear Regulatory Commission)

Lastly, today the mixed uranium and plutonium oxides (MOX) from reprocessing are used only once in thermal reactors due to the buildup of neutron absorbing Pu-240. Thus, this spent MOX fuel becomes waste to be managed.


Waste from Nuclear Weapons Production

The highly radioactive liquid waste from reactors used to produce plutonium for the nuclear weapons of the United States is stored in tanks (Figure 4) at the Hanford, Washington, and Savannah River, South Carolina. The Hanford site manages the largest volume of high-level waste, but the Savannah River site contains more total radioactivity. At Hanford, high-level waste alkaline liquid, salt cake, and sludge are stored in 149 single-shell and 28 double-shell underground tanks, while Savannah River has 51 tanks. These tanks contain approximately 88 million gallons of liquid, which is not only radioactive but also chemically toxic. The composition of the liquid varies from tank to tank.




Figure 4 - Waste Storage Tank

(Courtesy Department of Energy)
The U.S. Department of Energy has begun a process of mixing this waste with sand at high temperatures to form a liquid glass mixture, which is poured into stainless steel canisters where it solidifies and is sealed for permanent storage. This method of stabilization, known as vitrification, has also been used to process waste from power reactors.
Types of Nuclear Waste

According to the U.S. Department of Energy (DOE), the four major elements of the environmental legacy of nuclear weapons production are




  • waste,

  • contaminated environmental media,

  • surplus facilities, and

  • materials in inventory.

We will focus on the first two components. Nuclear weapons production in the United States is a complex series of manufacturing operations that generates large quantities of nuclear and chemical wastes. The term “waste” is defined as solids or liquids that are radioactive, chemically hazardous, or both. This waste consists of materials that have been disposed of previously, await disposal, or have been retrieved in site cleanups and are currently in storage.  Waste is measured in terms of its volume (cubic meters) and its radioactivity (curies). Waste from nuclear weapons production managed by DOE includes 24 million cubic meters containing 900 million curies.


The major categories of waste are

  • high-level waste,

  • transuranic waste,

  • low-level waste,

  • mixed low-level waste,

  • 11e(2) byproduct material,

  • hazardous waste, and

  • THER waste.


High-level waste is the highly radioactive waste resulting from spent nuclear fuel from production or power reactors, as well as from the chemical processing of spent nuclear fuel and irradiated target assemblies. The radioactivity comes from fission fragments and their daughter products resulting from the fission of U-235 in production reactors. Although radiation from short-lived fission products (fragments and their daughters) will decrease dramatically in the next hundred years, radiation risks associated with the long-lived products will remain high for thousands of years. In the initial decay period, most of the radioactivity is due to Cs-137, Sr-90, and their short-lived daughter products. Plutonium, americium, uranium, and their daughter products are the major contributors to long-term radioactivity. Figure 5 plots the radioactivity of high-level radioactive waste versus the numbers of years.


Figure 5 – Radioactive Decay of High-level Waste from Reprocessing One Ton of Spent Reactor Fuel
Transuranic (TRU) waste contains alpha-emitting transuranic elements or actinides with half-lives of greater than 20 years and a combined activity of greater than 100 nanocuries per gram of waste. Because of the long half-lives of many TRU isotopes, TRU waste can remain radioactive for hundreds of thousands of years. Some common isotopes found in TRU are Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, Am-241, and Cu-244. TRU waste results from the fabrication of plutonium components, recycling of plutonium from scrap, retired weapons, and chemical separation of plutonium. Unlike high-level waste, which results from a few specific processes with a narrow range of physical matrices and chemical characteristics, TRU waste exists in many forms with a spectrum of chemical properties.
A small percentage of TRU waste exhibits high direct exposure hazards and is referred to as "remote-handled" TRU waste. The majority of TRU waste emits low levels of direct radiation and is called "contact-handled" waste. The chief hazard of "contact-handled" waste is due to alpha radiation. Alpha particles cannot penetrate the skin but cause serious localized tissue damage when inhaled or ingested. When inhaled, TRU elements tend to accumulate in the lungs; soluble TRU compounds migrate through the body, accumulating in the bone marrow and liver.
Mixed low-level waste contains both chemically hazardous waste subject to the Resource Conservation and Recovery Act (RCRA) and radioactive materials. The radioactive component of mixed low-level waste is similar to low-level waste and thus less radioactive than high-level or TRU waste. Hazardous chemical components present in mixed waste include toxic heavy metals, explosives, halogenated organic compounds, and acids.
By-product materials include waste from uranium production described above. The other category is defined by government regulations. A variety of materials not covered previously fall into these categories. These materials include polychlorinated biphenyls, asbestos, and byproduct materials that have been mixed with chemically hazardous substances.
Waste Repositories in the United States

Two locations in the United States have been identified as repositories for nuclear waste. The operational Waste Isolation Pilot Plant (WIPP) located in southeastern New Mexico is a geologic repository for the disposal of waste such as clothing, equipment, rags, and other items contaminated with transuranic (TRU) elements resulting from nuclear weapons production. This TRU waste is defined as having activity greater than 100 nanocuries per gram due to transuranic isotopes. These isotopes have long half-lives, extending from 20 to thousands of years but much lower levels of radioactivity than the high-level radioactive waste. The waste is packaged in containers and emplaced in salt beds approximately 2,000 feet below ground. It is hoped that the salt will slowly close around the waste, permanently isolating it from the accessible environment.


Yucca Mountain, located about 100 miles northwest of Las Vegas, Nevada, has been selected as the site of a national geological repository for high-level spent nuclear fuel from civilian power plants and defense-related activities (Figure 6). This site is being studied carefully by the Department of Energy (DOE) to ensure public health and safety. If DOE determines that the site is suitable, it will submit a construction application to the Nuclear Regulatory Commission (NRC). As of this writing, the US DOE has been instructed by Presidential Executive Order to close this project permanently. No alternative facility or storage method has been suggested to replace it.



Figure 6 – Yucca Mountain Site in Nevada

Courtesy of the U.S. Department of Defense
As the licensing agency, the NRC will use standards currently being developed by the U.S. Environmental Protection Agency. However, conflicting scientific and technical information as well as strong political opposition from Nevada cloud the future of the site. As of 2009, no nation has opened a permanent repository for the storage of high-level nuclear waste. Most nuclear waste remains stored on the site at which it was produced.
Therefore, the nature and extent of the problem can be easily defined. The only way the dangers intrinsic to high-level radioactive waste materials can be effectively remediated requires the implementation of a methodology that can be shown by carefully controlled experimental protocols to effectively reduce the half-life of radioactive materials with each successive interaction, while at the same time reducing concomitant alpha and beta emissions and gamma ray intensity to ambient background levels. In short, what is required is a treatment technique that effectively disrupts the strong nuclear force [which binds the nuclear particles together] without creating a critical, uncontrollable, catastrophic fission event in the process.
To accomplish this, a number of factors have to be taken into consideration. Unfortunately, after more than 70 years of research and development in the field there is still no consensus about the crucial dynamics which are believed to contribute to the behavior and properties of radioactive isotopes. Models have been developed to describe the behavior of single atoms using newly developed non-linear software modeling systems, but no interactive dynamic modeling system has been developed that is capable of accurately evaluating the 4D interactions between isotopes of any elements with atomic numbers greater than 25. All the elements we are charged with treating are heavier than this upper modeling limit. Therefore, the task of estimating how much extrinsic energy must be applied to effectively disrupt the strong nuclear binding force in any aggregation of interactive radioactive isotopes remains largely speculative.

Nevertheless, it is possible to predict with some certainty what ought to happen when sufficient disruption energy has been effectively applied to a target material. During the development and experimental validation of the proposed methodology, sophisticated instrumentation was used to analyze the products generated by the treatment process. The results reported by the test protocols clearly validate that the methods we have developed work as intended.


Unanswered Questions

Among the questions that must be addressed, the following are of primary importance:





  1. Variable treatment requirements for liquid waste v. solid waste [statistical assessment in gallons, tons, approaches, methodologies, technological alternatives etc.]




  1. Calculations – nuclear bonding energies. What is the threshold energy required to temporarily disrupt the integrity of the targeted nucleus?




  1. Modeling requirements – Schematic diagrams, animated illustration of nuclear structures in action, individually and adjacent to other materials in a crystalline lattice




  1. Calculations – Stochastic electrodynamic [SED] model of radioactive decay [i.e., how many decay stages are needed to reduce current emission structure to generate ambient background levels of gamma, alpha & beta emissions]




  1. Calculations – When minimal disaggregation energy is applied, how much energy is released over what ∆t? What form does the output energy take? What is required to manage it?




  1. Calculations – When temporary disaggregation occurs, how long before reformation occurs, and in what form(s)? What effect does this dynamic exert on half-life and rate of radioactive emissions and decay cycles? Proposed Methodology


Proposed Approach
Liquefied Radioactive Waste
Most treatment and conditioning processes for low and intermediate-level radioactive waste have now reached an advanced industrial scale. Although these processes and technologies are sufficient for effective management of radioactive waste at nuclear power plants, further improvements in this technology are still possible and desirable. The increasing cost of radioactive waste disposal provides an incentive to adopt procedures and techniques to minimize waste quantities and to develop new techniques to minimize volumes at the treatment and conditioning step.
Some examples of such new developments include the use of specific inorganic sorbents to improve liquid waste treatment; use of membrane techniques for liquid waste treatment; de-watering and drying of bead resin and filters slurries; incineration of spent ion-exchange resins; dry cleaning of protective cloth to reduce quantity of laundry drains; use of high integrity containers for packaged dried filter sludges; vitrification of some intermediate-level waste to reduce volumes of waste to be disposed of; and super-compaction of unburnable waste.

Extraordinary Voltage Objects Model
Background
For more than twenty years, scientist Kenneth Shoulders has conducted independentl laboratory experiments focused on a naturally occurring phenomenon exhibited by lightning strikes. The phenomenon is referred to in his patents46 and the scientific literature as ‘High-Density Charge Clusters’ [HDCC]. Shoulders’ latest documents refer to charge clusters as ‘Extraordinary Voltage Objects’ [EVO's]. Other prominent scientists around the world have applied for and been awarded patents for similar discoveries in the field.47
High-Density Charge Clusters

High-density charge clusters consist of micron-sized clusters of electrons, which exhibit soliton-like [standing wave, e.g. a smoke ring] behavior. A typical cluster has been experimentally shown to exhibit electron number density approximately equal to Avogadro's number. These intense clusters of electrons are produced by an explosive electron emission, typically produced on the tip of a metallic needle cathode positioned adjacent to a dielectric (i.e. a metal dielectric vacuum contact point, or triple point) in a vacuum or low-pressure gas environment. The electron cluster is produced by application of a short negative pulse ranging from a few hundred to tens of thousands of volts to the cathode. In laboratory experiments recently conducted in the US, HDCC have been repeatedly and consistently produced by a system, which generates 2.5 kilovolts in a one-nanosecond discharge. Charge clusters were first discovered and developed into new integration by Kenneth Shoulders in the US. The US Patent and Trademark Office as a result of his work has issued several patents.48,49,50,51 Similar and independent discoveries have also been made and reported by G.A. Mesyats of Russia who referred to their discovery as "Ectons".52


A typical individual charge cluster measures on the order of one micron, comprised of electrons numbering on the order of 1011 (i.e., electron number densities approaching that of a solid, ~ 6 x1023 per cubic centimeter). An analytical investigation to determine the self equilibrium of the moving charge clusters and the conditions under which a dynamic equilibrium state could exist, has been accomplished by S. X. Jin, et al.53. This analysis of a plasma fluid description provided, for the first time, analytical criteria, which describes the dynamic conditions under which a charge cluster can exist. This analysis showed that the HDCC is a self-organized toroidal electron vortex. Such an electron vortex has been shown to exist at various combinations of electron densities, velocities, and cluster sizes, all of which satisfy the criteria.
HDCC’s exhibit a tendency to link up like beads in a chain. The spacing of the beads in the chain is approximately equal to the diameter of the individual beads. The HDCC chains have been observed to form closed ring-like structures as large as 20 microns in diameter54,55,56,57.


Figure 1 - EVO Plasma Discharge [Jin]58
In his research, Shoulders discovered that when a high-energy burst of electrons is emitted at the tip of a properly constructed probe, and directed toward a target material, which is placed in front of an anode, in the presence of properly aligned magnetic fields and in the presence of a proton-rich plasma [e.g., deuteride gas] contained in a vacuum chamber, the cloud of electrons emitted at the tip of the probe organizes itself into a toroid measuring 1 micron in diameter.[59]



Figure 2 - T. Banchoff – Flat Torus in 3-Sphere60

The toroidal form of the EVO has been photographed with high-resolution tunneling electron microscopes at the point of emission. This phenomenon, which demonstrates the dynamics of self-organizing criticality and super-symmetry at sub-atomic scales, is specifically prohibited by the standard model of physics because it is believed to violate the Pauli exclusion principle.





Figure 3 - Shoulders - (a) EV & (b) EV Chain



F
Figure 4
igure 4 - Collective Ion Accelerator Layout Scheme

Nevertheless, as the photographic and digital imaging evidence shows, the toroid formed by the self-organizing behavior of the electrons in a vacuum/plasma is both stable and can be directed through a proton-rich environment along the flux lines of a properly aligned magnetic field, to collide with a target material.



The multiple EVO strikes [shown in Fig. 5] are caused by an induction coil-driven electrode being scanned along the top side of the foil with a spacing of about .75 inch. In some regions the EVO penetrates the 0.02-inch thick coating and 0.001 inch thick foil carrying the fluid out the back side showing as a flare in the photo. In other cases, the EVO penetrates the coating and foil and then reverses direction carrying the fluidized SiC out the entry direction with high velocity.61



Figure 5 - Edge View of Multiple EVO Strikes in Air on an

Aluminum Foil with SiC amd Epoxy Mix
Coming from the EVO source at the lower portion of the pinhole camera image, the EVO is seen to follow a helical pattern of motion and decomposing into the individual electrons as it moves at a rate of 1/10 the velocity of light to the top of the photo. The length of the EVO run in this photo is approximately 0.1 inches. This type of charge motion produces a chirped spectrum of radiation sweeping from higher to lower frequencies.62


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