scholarly journals No Hurry to Recycle

2006 ◽  
Vol 128 (05) ◽  
pp. 32-35
Author(s):  
Frank N. Von Hippel

This article discusses the promotion of Global Nuclear Energy Partnership (GNEP) by US Department of Energy. GNEP is a strategy for dealing with the accumulation of radioactive waste from power plants by reprocessing some of the spent fuel. The primary domestic benefit of this initiative would be to reduce the quantity of plutonium and other transuranic waste that would have to be buried in Yucca Mountain, the Nevada site identified as the national depository for nuclear waste. The objective of GNEP is to fission all of the transuranics, aside from process losses. The National Academy of Sciences (NAS) study scaled its cost estimate to 62,000 tons of spent fuel because that is approximately the amount of spent fuel that the Nuclear Waste Policy Act allows to be placed in Yucca Mountain before a second repository in another state is in operation. The huge cost of the GNEP would likely be more of a burden than a help to the future of nuclear power in the United States.

10.6036/10156 ◽  
2021 ◽  
Vol 96 (4) ◽  
pp. 355-358
Author(s):  
Pablo Fernández Arias ◽  
DIEGO VERGARA RODRIGUEZ

Centralized Temporary Storage Facility (CTS) is an industrial facility designed to store spent fuel (SF) and high level radioactive waste (HLW) generated at Spanish nuclear power plants (NPP) in a single location. At the end of 2011, the Spanish Government approved the installation of the CTS in the municipality of Villar de Cañas in Cuenca. This approval was the outcome of a long process of technical studies and political decisions that were always surrounded by great social rejection. After years of confrontations between the different political levels, with hardly any progress in its construction, this infrastructure of national importance seems to have been definitively postponed. The present research analyzes the management strategy of SF and HLW in Spain, as well as the alternative strategies proposed, taking into account the current schedule foreseen for the closure of the Spanish NPPs. In view of the results obtained, it is difficult to affirm that the CTS will be available in 2028, with the possibility that its implementation may be delayed to 2032, or even that it may never happen, making it necessary to adopt an alternative strategy for the management of GC and ARAR in Spain. Among the different alternatives, the permanence of the current Individualized Temporary Stores (ITS) as a long-term storage strategy stands out, and even the possibility of building several distributed temporary storage facilities (DTS) in which to store the SF and HLW from several Spanish NPP. Keywords: nuclear waste, storage, nuclear power plants.


Author(s):  
Donald Wayne Lewis

In the United States (U.S.) the nuclear waste issue has plagued the nuclear industry for decades. Originally, spent fuel was to be reprocessed but with the threat of nuclear proliferation, spent fuel reprocessing has been eliminated, at least for now. In 1983, the Nuclear Waste Policy Act of 1982 [1] was established, authorizing development of one or more spent fuel and high-level nuclear waste geological repositories and a consolidated national storage facility, called a “Monitored Retrievable Storage” facility, that could store the spent nuclear fuel until it could be placed into the geological repository. Plans were under way to build a geological repository, Yucca Mountain, but with the decision by President Obama to terminate the development of Yucca Mountain, a consolidated national storage facility that can store spent fuel for an interim period until a new repository is established has become very important. Since reactor sites have not been able to wait for the government to come up with a storage or disposal location, spent fuel remains in wet or dry storage at each nuclear plant. The purpose of this paper is to present a concept developed to address the DOE’s goals stated above. This concept was developed over the past few months by collaboration between the DOE and industry experts that have experience in designing spent nuclear fuel facilities. The paper examines the current spent fuel storage conditions at shutdown reactor sites, operating reactor sites, and the type of storage systems (transportable versus non-transportable, welded or bolted). The concept lays out the basis for a pilot storage facility to house spent fuel from shutdown reactor sites and then how the pilot facility can be enlarged to a larger full scale consolidated interim storage facility.


Author(s):  
H. Shah ◽  
R. Latorre ◽  
G. Raspopin ◽  
J. Sparrow

The United States Department of Energy, through the Pacific Northwest National Laboratory (PNNL), provides management and technical support for the International Nuclear Safety Program (INSP) to improve the safety level of VVER-1000 nuclear power plants in Central and Eastern Europe.


2002 ◽  
Vol 8 (1) ◽  
pp. 3-9 ◽  
Author(s):  
Zhuang Sun ◽  
J. Donald Rimstidt

Abstract The United States is currently planning to bury high-level radioactive wastes from commercial nuclear power plants and from weapons production in a mined repository in tuff deposits under Yucca Mountain, Nevada. Radioactive decay in these wastes will create steep thermal gradients in the rocks surrounding the repository. This heat might cause the pore water in these tuffs to evaporate, migrate as vapor to cooler areas, and condense to form a solution that can aggressively dissolve the surrounding tuff. Under certain circumstances the silica-rich, bicarbonate solutions produced by this process could migrate under the influence of gravity back toward the canisters where the water would again evaporate leaving amorphous silica behind to form a low permeability silica cap above the repository. Over time, a perched water table containing carbonate and colloidal silica-rich brine could develop above the repository. Thermoelastic fracturing of the silica cap might allow this brine to flow into the repository. We developed a vertical thermal gradient experiment that simulates the silica dissolution and transport processes and used it to determine that each Joule of heat can leach and transport as much as 1.85(+ or -0.56)X10 (super -8) g of silica from a crushed sample of the Topopah Springs Member of the Paintbrush Tuff. Based on this value and the thermal models of Moujaes and Lei (1995), we estimate that the heat from each canister of waste might transport as much as 31.7 kg of silica during the first 100 years and as much as 136 kg of silica during the first 1,000 years after emplacement. Assuming a reasonable fracture density and a 30 mX30 m area of influence for each canister, we estimate that the silica cap above the repository could grow to be 2.1 mm thick after 100 yr and 9.1 mm thick after 1,000 yr.


Author(s):  
Raymond L. Clark ◽  
Kenneth Czyscinski ◽  
Reid J. Rosnick ◽  
Daniel Schultheisz

In 2001, as directed by the Energy Policy Act of 1992, the United States Environmental Protection Agency (EPA) issued public health and environmental radiation protection standards for the proposed repository at Yucca Mountain, Nevada. Several parties sued the Agency on numerous aspects of the rule. A Federal Court upheld EPA on all counts except for the compliance period associated with the individual-protection standard, which the Agency had limited to 10,000 years for a number of technical and policy reasons. However, the National Academy of Sciences (NAS) had recommended that the standard be set for the time of peak risk, within the limits imposed by the long-term stability of the geologic environment, which NAS estimated at 1 million years. EPA’s standards required that the Department of Energy (DOE) project doses to the time of peak dose but did not apply a compliance standard to these longer term projections. The Court ruled that EPA’s 10,000-year compliance period was inconsistent with the NAS recommendation. This aspect of the rule was vacated and remanded to the Agency for revision. In 2005, EPA proposed amendments to the standards. Following public hearings and a public review period, the final amendments were issued in September 2008. This paper discusses the new requirements.


Author(s):  
Rudrapati Sandesh Kumar ◽  
Payal Shrivastava

Finding a solution for nuclear waste is a key issue, not only for the protection of the environment but also for the future of the nuclear industry. Ten years from now, when the first decisions for the replacement of existing nuclear power plants will have to be made, The general public will require to know the solution for nuclear waste before accepting new nuclear plants. In other words, an acceptable solution for the management of nuclear waste is a prerequisite for a renewal of nuclear power. Most existing wastes are being stored in safe conditions waiting for permanent solution, with some exceptions in the former Eastern Bloc. Temporary surface or shallow storage is a well known technique widely used all over the world. A significant research effort has been made by the author of this paper in the direction of underground repository. The underground repository appears to be a good solution. Trying to transform dangerous long lived radionuclides into less harmful short lived or stable elements is a logical idea. It is indeed possible to incinerate or transmute heavy atoms of long lived elements in fast breeder reactors or even in pressurised or boiling water reactors. There are also new types of reactors which could be used, namely accelerator driven systems. High level and long lived wastes (spent fuel and vitrified waste) contain a mixture of high activity (heat producing) short lived nuclides and low activity long lived alpha emitting nuclides. To avoid any alteration due to temperature of the engineered or geological barrier surrounding the waste underground, it is necessary to store the packages on the surface for several decades (50 years or more) to allow a sufficient temperature decrease before disposing of them underground. In all cases, surface (or shallow) storage is needed as a temporary solution. This paper gives a detailed and comprehensive view of the Deep Geological Repository, providing a pragmatic picture of the means to make this method, a universally acceptable one.


Author(s):  
Jas S. Devgun

The experience related to decommissioning of nuclear facilities in the United States is very substantial and covers power reactors, research reactors, and many facilities in the Department of Energy complex. The focus of this paper however is on the commercial power plants. With 104 operating reactors, the U.S. fleet of civilian reactors is still the largest in the world. Nuclear power industry in the United States has undergone a dramatic upturn after decades of stalemate. One effect of this nuclear renaissance has been that the plans have changed for several reactors that were initially destined for decommissioning. Instead, the focus now is on relicensing of the reactors and on power uprates. In fact, after the peak period between 1987 and 1998, no additional power reactors have been shutdown. On the contrary, power uprates in the past twenty years have added a cumulative capacity equivalent to five new reactors. Almost all the operating reactors plan to have license extensions, thus postponing the eventual decommissioning. Nevertheless, in addition to the 9 reactors where licenses have been terminated following decommissioning, 12 power and early demonstration reactors and 14 test & research reactors are permanently shutdown and are in decommissioning phase. Substantial experience and lessons learned are available from the U.S. projects that are of value to the international decommissioning projects, especially where such projects are in early stages. These lessons cover a wide array of areas from decommissioning plans, technology applications, large component removal, regulatory and public interface, decommissioning funding and costs, clean up criteria, surveys of the decommissioned site, and license termination. Additionally, because of the unavailability of a national spent fuel disposition facility, most decommissioning sites are constructing above ground interim storage facilities for the spent nuclear fuel. The U.S. nuclear power projects are also gearing up for the design and licensing of new reactors. Lessons from the past are useful in the development of such designs so that along with the other factors, the designs are optimized for eventual decommissioning as well. This paper provides an overview of the past reactor decommissioning, lessons learned from the past experience, and status of the current decommissioning activities and issues. It also presents some long term projections for the future of decommissioning in the United States.


Author(s):  
Stephen M. Hess ◽  
Nam Dinh ◽  
John P. Gaertner ◽  
Ronaldo Szilard

The concept of safety margins has served as a fundamental principle in the design and operation of commercial nuclear power plants (NPPs). Defined as the minimum distance between a system’s “loading” and its “capacity”, plant design and operation is predicated on ensuring an adequate safety margin for safety-significant parameters (e.g., fuel cladding temperature, containment pressure, etc.) is provided over the spectrum of anticipated plant operating, transient and accident conditions. To meet the anticipated challenges associated with extending the operational lifetimes of the current fleet of operating NPPs, the United States Department of Energy (USDOE), the Idaho National Laboratory (INL) and the Electric Power Research Institute (EPRI) have developed a collaboration to conduct coordinated research to identify and address the technological challenges and opportunities that likely would affect the safe and economic operation of the existing NPP fleet over the postulated long-term time horizons. In this paper we describe a framework for developing and implementing a Risk-Informed Safety Margin Characterization (RISMC) approach to evaluate and manage changes in plant safety margins over long time horizons.


2021 ◽  
Vol 87 (4) ◽  
pp. 111-116
Author(s):  
Anatoliy Omelchuk

Scientists of the V.I. Vernadskii Institute of General and Inorganic Chemistry of National Academy of Sciences of Ukraine developed a method of electrochemical removal of radionuclide contamination from the surfaces of the technological equipment of nuclear power plants. The method was successfully tested at the Chornobyl nuclear power plant and on the Research Nuclear Reactor of the Institute of Nuclear Research of the National Academy of Sciences of Ukraine. Based on the results of the tests, a device for the electrochemical decontamination of metal surfaces of equipment in non-stationary conditions was created and design and technological documentation for its serial production was developed.


2012 ◽  
Vol 1475 ◽  
Author(s):  
D. J. Duquette ◽  
C. A. W. Di Bella ◽  
R. M. Latanision ◽  
B. E. Kirstein

ABSTRACTNuclear waste isolation programs both inside and outside the United States have provided evidence that there are many geologic options for a repository, but virtually all of them rely to some degree on an engineered barrier system (EBS) to isolate and/or retard the migration of radionuclides to the biosphere. At Yucca Mountain, the design of the EBS was unexpectedly challenging because of uncertainties in quantitatively determining the local environment of the EBS particularly during the thermal pulse. The EBS design for the Yucca Mountain site evolved from a thin-walled, limited-lifetime, corrosion-resistant canister through a corrosion-allowance canister, to the present design, which may have a lifetime of more than 106 years. The EBS proposed for the Yucca Mountain repository has many individual sub-barriers, beginning with the spent fuel and waste, the cladding of the spent fuel, the geometry of the package, etc. The anticipated modes of degradation of engineering materials, including corrosion of the fuel, of the canister, and of the drip shield proposed specifically for the Yucca Mountain project, and the consequences of the materials degradation on the performance of the repository are presented. The roles of conservative modeling and simplifying assumptions for radionuclide mobilization and transport in the EBS on characterization of the source term are addressed.


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