This chapter presents an editorial view of essential elements for an effective D&D technology development program, and a compendium of challenges and needs from the perspective of technology end-users. The term “D&D” is used herein to describe a formal project management process that involves removal of real property from active or standby status and transition to a long-term end state (such as an industrial brown-field or an unrestricted green-field). Interim steps depend on the actual facility, and include characterization, deactivation, decommissioning, decontamination, demolition, waste management, and disposition or recycling of excess facilities and equipment. Life-cycle-cost analyses include surveillance and maintenance (S&M) while awaiting completion of D&D.

Chapter 55, authored by Anibal L. Taboas for the second edition has been completely revised for the current third edition. In this edition, author presents an editorial view of Decommissioning Technology Development within a context that energy, environment, education, and economy are inextricably linked. The author highlights related approaches by the US Department of Energy and the UK Nuclear Decommissioning Authority. The causes and contributing factors to significantly increased cost estimates are discussed, as well as the cost of delay (missed regulatory opportunities, reluctance to cut back non-productive expenditures, a bias against innovation, and lack of incentives for transition to other significant missions after the completion of environmental remediation). A compendium of technology challenges and needs is presented, along with an overall program performance rating. The author observes that (1) funding for basic, long, and medium term components, has dwindled as to support primarily paper [or desk] studies, (2) fiduciary responsibility requires demonstrating whether the resources consumed by industry and government in the safe and compliant environmental remediation of radiological and nuclear facilities remains commensurate with the risks averted, and that (3) reverting the funding trend in D&D technology development requires integrated planning, strategic action, and effective communication. The chapter concludes with a call for a plan to (1) develop the business case for investment; (2) invest in high visibility projects of demonstrably high return for investment; (3) meet customer-identified expectations; (4) track leading indicators and contractual incentives; (5) resolve key policy issues; and (6) transparent independent peer review.

Chapter 55, authored by Anibal L. Taboas, provides an overview of the deactivation, decontamination and decommissioning (commonly known as D&D) of nuclear facilities. This chapter addresses the determination of decommissioning alternatives, the planning required for decommissioning (both preliminary and detailed project planning), facility characterization, decommissioning operations and project close-out. The decommissioning alternatives address approaches acceptable to the U.S. NRC, and approaches used by U.S. DOE facilities. Decommissioning pre-planning discusses the regulatory requirements of a number of federal agencies including the U.S. NRC, U.S. EPA, OSHA and U.S. DOT. Decommissioning financial considerations are also addressed along with clearance criteria, license termination, use of technology, radiation exposure, project management quality assurance, public and stakeholder participation and other aspects of pre-planning. Characterization addresses the determination of site and facility contaminants (both radioactive and non-radioactive that may require remediation). Additionally the chapter addresses the detailed project management approaches including cost estimating and scheduling required to effectively complete a decommissioning project. Lastly, the chapter addresses actions needed for effective project closeout and potential actions needed for long term site monitoring or maintenance. This chapter is based primarily on “The Decommissioning Handbook”, published by ASME in 2004, which includes an extensive bibliography and a compact disk with technology descriptions.

Decommissioning brings to closure, or terminates, the mission or useful life of a radiological or nuclear facility. The owner or licensee normally decides when a facility is to permanently cease operations. It must then show that a proposed decommissioning project plan can be conducted safely, and that at completion the facility will comply with regulatory requirements. This chapter presents a road map of the decommissioning process, highlighting the major issues to address in planning, implementing, and completing a project, and including references for further detail.

During the more than half-century history of the U.S. weapons programs, a vast research, production, and testing network was developed that came to be known as the “nuclear weapons complex..” The DOE and its predecessor agencies have been responsible for most of these facilities. DOE-owned plants and equipment include: - Facilities for uranium milling and refining - Gaseous diffusion plants for producing weapons-grade uranium - Facilities for fabricating and testing weapons - Nuclear reactors for testing materials and equipment components - Nuclear reactor prototypes - Cyclotrons - Hot Cells - Research laboratories They also included reactors for making tritium, plutonium, and radioactive and stable isotopes of many elements; and chemical separation facilities for extracting uranium, plutonium, and other radionuclides.

This chapter focuses on decontamination activities at nuclear and radiological facilities regulated by the NRC. If a state is an NRC Agreement State, certain nuclear-related facilities (excluding federal facilities and nuclear power reactors) may be regulated through the relevant individual state agency. The NRC normally accomplishes its regulatory function by issuing and then enforcing the provisions of a license. It licenses and regulates nuclear reactors (both power and nonpower generating) and over 6,000 radioactive material licensees (NRC 2003a). The NRC also regulates several DOE facilities, either by mutual agreement or by specific statute. A relevant example of statute regulation is the licensing of the permanent geologic repository at Yucca Mountain for the disposal of spent nuclear reactor fuel and high-level waste (HLW).

This chapter summarizes the major environmental laws relevant to decommissioning. Whereas the Atomic Energy Act (AEA 1954) is the primary law governing the management of radionuclides, the Resource Conservation and Recovery Act (RCRA) is the primary law governing hazardous waste. Other statutes also address the release and disposal of radioactive and hazardous materials. Although the DOE, the NRC, and the Environmental Protection Agency (EPA) are the primary agencies implementing these requirements, much of the authority to develop environmental regulations and enforce them has been delegated to the states. It is not practical to address the individual state environmental requirements in this handbook, many of which are similar to the federal requirements.

In general, environmental laws, regulations, and other requirements for decommissioning of facilities under DOE management are interpreted and communicated through a directives system and are imposed on specific projects through contracts. The internal focus is on the final phases of the life cycle, including deactivation, decommissioning, surveillance and maintenance, and any potential transfer of ownership. The management system includes mandatory requirements, such as policy notices, orders, notices, and manuals, and guidance with some implementation flexibility, including the graded application of certain technical standards and guides. In addition, the management system is supported by optional handbooks, voluntary standards, and other documents illustrating established practices for meeting requirements. A thorough understanding of this system requires acceptance that the DOE is a mission-oriented federal agency with its share of statutory intricacies, diverse sites, and a diverse set of contractors.

Decommissioning of nuclear facilities requires attention not only to radiation safety but also to other safety requirements collectively referred to as occupational safety and health (OSH). As a general rule, a safety assessment is the initial phase of both radiation safety and OSH. The safety assessment identifies significant hazards during the decommissioning phase of a nuclear facility that are not normally encountered during the operational phase. Hazardous materials are major factors in the decommissioning of old nuclear facilities and represent a risk to the operators undertaking the work. Examples of common hazardous materials are lead, asbestos, PCBs, mercury, and beryllium. All require special disposal. The handling and disposal of mixed (hazardous and radioactive) wastes can pose special problems since, unlike radioactive materials with a relatively short half life, hazardous chemicals may pose a health hazard for a much longer (if not indefinite) time. If decommissioning will be long deferred, due regard should be given to the gradual deterioration of structures, systems, and components. Upon permanent shutdown, a facility should undertake a critical review of all site records (paper, microfilm, and electronic formats) and should resist the initial urge to eliminate records used “for operations only.” Records are critical assets for decommissioning planning; their maintenance and accessibility should preclude any decision as to reductions in related site staffing. Decommissioning normally follows deactivation, and often is followed by long-term storage with S&M. A long time may pass between facility operation, deactivation, and final decommissioning. The S&M activities focus on monitoring and controlling any remaining hazardous substances or contamination and maintaining the facility's structural integrity. In some cases, facility operations may be temporarily suspended, then indefinitely shut down, establishing an S&M phase by default.

Decommissioning a nuclear facility requires a multitude of decisions that may have wide ranging effects. One critical aspect to consider in making decisions is the risk of potential adverse impacts on the facility workforce, the public, and the ecosystem. According to the American Association of Engineering Societies, risk analysis may be considered to include three essential modules: assessment, management, and communication. These modules are interrelated, as shown in Figure 7.1 (AAES 1998).

The end of a nuclear facility's mission and its transition into decommissioning can create substantial hardship on nearby communities, particularly in the case of major facilities built at a distance from large metropolitan areas. A rural setting often promotes the establishment or growth of smaller communities around the nuclear facility that come to rely heavily on the facility for their economic well-being, either directly through taxes, or more indirectly, by services and support functions to the facility and its employees. Eliminating permanent staff during plant closing can result in significant negative economic effects, although a temporary local economic upturn is possible as specialized contractors, managers, and laborers move to the area for lengthy decommissioning activities. Because of these financial impacts, local community opinion could be anywhere from neutral to negative initially, even if shutdown were announced well in advance. The reaction can be more dramatic in the event of swift or unannounced plant closures. This chapter gives a general overview of public and stakeholder participation. In the past, many agencies and organizations responsible for decommissioning made no distinction among various segments of the public. In effect, they identified stakeholders as anyone wishing to be involved. That approach fails to distinguish the general public from people clearly and unambiguously impacted by decommissioning decisions. Furthermore, such an approach makes it virtually impossible to reach the stakeholders of primary concern. The process described here is based on new developments in stakeholder participation and was used by the Peer Review Committee of the American Society of Mechanical Engineers and the Institute for Regulatory Science (ASME/RSI) and has since been applied in several peer reviews (ASME/RSI 2001 and 2002).

Initial decommissioning planning occurs, whether intended or not, before the decision is made to permanently cease operations. The initial planning assessments completed by the facility owner are defined to generate specific and sufficient information, including costs related to continuing operation for specific time periods, ceasing operation by a specific date, and determining the type of decommissioning to pursue and a start date for preliminary activities. Key decisions finalized early in the planning process to make for a safe and cost effective project. There are many examples of nuclear facilities where a determination was made to cease operations for an indeterminate time period, while assessments regarding the facility's future use were completed. Examples include the U.S. Department of Energy's (DOE) Fast Flux Test Facility remaining in hot standby until early 2003 (Lanais 1993), and Millstone Unit 1, a commercial nuclear reactor now in safe storage. In some cases, initial decommissioning studies are performed while a facility is in this shutdown pre-decision mode, A commercial power reactor facility in hot standby requires considerable expenditures to satisfy the U.S. Nuclear Regulatory Commission (NRC) requirements so that the facility might be returned to operation at a reasonable cost without re-testing equipment. This approach is costly since no operational benefits are derived but costs near operating level continue. The costs may be significantly less for small DOE reactors, and may be much less than normal operating costs for non-reactor facilities. Though not required before starting decommissioning activities, determining the ultimate end-state of the facility and the site is a critical decision. Substantially different approaches may be implemented for a facility that will be remediated for potential residential use (greenfield) than for one that is to be partially demolished for potential industrial reuse (brownfield). In the greenfield approach, almost everything with discernible radioactive contamination would likely be removed and shipped off site for disposal. In the brownfield approach there are more options. For example, only some of the high radioactive content structures and components may be dismantled for off site disposal. Only a portion of the above- and below-grade structures might also be removed, along with some of the contaminated soil beneath. While above-grade portions of buildings on a brownfield site may be demolished, their foundations may remain in place with little or no decontamination. Structures intended for reuse might have their internal radioactive components removed and the remaining interior surfaces decontaminated to sufficiently suitable limits to allow unrestricted reuse of the remaining space.

This chapter describes the collection of information needed to plan the decommissioning of a nuclear facility. Characterization is frequently thought of as synonymous to radiation measurement, but the term has a broader meaning. Characterization is the collection of all information needed to describe, in adequate detail, the following: - The hazards present at/in the facility - The condition of the facility structure as it may affect worker health and safety - The extent, nature, and concentration of radiological and hazardous chemical contamination - The institutional, legal, and technical restraints on decommissioning alternatives Characterization is an iterative process that precedes and parallels actual decommissioning. The characterization program discussed here is in support of decontaminating structures to protect workers and future site occupants, but this effort is intimately related to the consideration of ground contaminants, beneath and around the structure, and their potential travel to off-site environs.

Performing site and facility characterisation assessments is often complex Chapter 10 presented the needs for a facility undergoing decommissioning. As discussed in Chapter 7, a key aspect to risk assessment is the evaluation of radiological exposures to hypothetic My maximum exposed individuals.. Computer-based tools have been developed to help address these challenges. This chapter specifically discusses three computer-based aids developed by government agencies for the conduct of decommissioning, namely RESRAD, DandD, and Compass, together with MARSSIM, and the adaptive characterization approach they support. RESRAD and DandD are used to conservatively calculate exposures to the maximum exposed individual through multiple pathways, based on measured values of residual radioactive contamination, These two codes are the primary dose modeling approaches considered acceptable by the NRC and DOE. Compass is a code used to automate some processes from the MARSSIM characterization protocols. The MARSSIM methodology provides information on planning, conducting, evaluating, and documenting the final status radiological surveys of building surface and surface soils for demonstrating compliance with dose- or risk-based regulations or standards. MARSSIM is a multi-agency consensus document that was developed collaboratively by four federal agencies having authority and control over radioactive materials: the Department of Defense (DOD), the DOE, the EPA, and the NRC. The manual was originally issued in December 1997 as NUREG-1575 (NRC 1997a) and then as NUREG 1575, Rev.1 (NRC 2000a) in August 2000 to incorporate comments received on the 1997 version. Errata and modifications that were included in Revision 1 are shown on page xxviii of that document. In general, the two versions are quite similar; the former is part of the documentation of completed projects and the latter is used for future and on-going projects. This chapter also addresses two approaches to characterization in decommissioning, MARSSIM is widely used to optimize a characterization program while helping ensure statistical validity of the results. The program is focused toward field radiological characterization. The second approach is an adaptive sampling and analysis program that has been demonstrated to improve cost and time performance objectives for characterization (DOE 2001c).

The decommissioning cost estimate and schedule do not stand-alone; they are an integral part of the planning for a project from the concept to the final implementation. The cost estimate and schedule are linked inseparably, as changes to the cost affect the schedule, and vice versa. Only with an accurate cost estimate and schedule can management usefully track costs and project trends. Reliable cost estimating is one of the most important elements of decommissioning planning. Alternative technologies may be evaluated and compared based on efficiency and effectiveness, and measured against a baseline cost as to the feasibility and benefits derived. When the plan is complete, those cost considerations ensure that it is economically sound and practical for funding. Estimates of decommissioning costs have been performed and published by many organizations. The results of an estimate may differ because of different work scopes, different labor force costs, different money values because of inflation, different oversight costs, the specific contaminated materials involved, the waste stream and peripheral costs associated with that type of waste, or applicable environmental compliance requirements. Some of the divergence in costs, however, cannot be easily explained, and this lack of consistency prohibits direct estimating by measuring standard quantities, such as initial capital east, facility size (megawatts), square footage of facilities, or volumes of waste streams. At some point, it may be possible to multiply one or more of these measurements by some predetermined number to arrive at a cost estimate. But until such a system is proven to be reliable, a reasonable degree of reliability and accuracy can only be achieved by developing decommissioning cost estimates on a case-by-case basis.

The decisions and process for decommissioning nuclear facilities play a key role in controlling radiation exposures. The immediate goals of such projects are to reduce or eliminate occupational and public radiation exposures, primarily by isolating contaminants from surfaces and subsurfaces, and to enable cost effective radioactive waste management and disposal. Decisions that define the applicability of various processes and techniques arc at the heart of decommissioning. Potential techniques include washing, heating, chemical or electrochemical action, mechanical cleaning, and others. For large facilities and equipment, applicable methods are mostly chemical or mechanical. For components that have a role in a facility with a continuing operation mission, dilute chemical agents are typically used to nondestructively dissolve just the outermost surface film bearing most of the contamination. Conversely, if there is no potential for reuse, the base metal can also be dissolved. The process for a small contaminated metal shack may he brief, as compaction may be obviously the most viable option, while a large highly radioactive facility may require more complex processes, including options, such as the wide use of robotics. Intermediate project objectives on the path to restoring the facility to a defined end state include: - Removing loose radioactive contaminants and fixing the remaining contamination - Minimizing residual radioactive contamination requiring protective storage - Maximizing recycle and salvage of equipment and materials - Minimizing volume requiring disposal as radioactive waste - Segregating waste for shipping and disposal in the least restrictive acceptable form (e.g., unrestricted, clean rubble, sanitary, special class, surface contamination only, hazardous, radioactive low-level, mixed hazardous and radioactive, remote handled, and transuranic waste) - Minimizing any period requiring protective storage or long-term monitoring When chemical decontamination is indicated, it may be necessary to temporarily dedicate appropriate facilities for precipitation, filtration, evaporation, demineralization, stabilization, recycling, and or reclamation. Residual concentrates may represent a significant source of radiation before transportation for treatment and/or disposal. Each step is an expense to the budgeted occupational dose and increases the risk of an unplanned release, such as the uptake of radioactive material that results in higher doses than those from handling the contaminated system without extensive decontamination. Planning is therefore the process of selecting options based on a continual and iterative cost-benefit analysis.

This chapter presents information related to spent fuel acceptance, management, storage options, and the operational and financial considerations faced before and during decommissioning. The generation of electricity by nuclear fission creates highly radioactive waste in the form of spent fuel. As each reactor is refueled, one-fourth to one-third of the fuel is removed and placed in the plant's storage pool, which shields and cools the spent assemblies. Since these fuel pools were initially designed for provisional storage, most plants cannot store all the assemblies generated over the expected reactor operating life. In the late 1960s and early 1970s, assemblies could be transferred off site for reprocessing, freeing up additional space in the storage pools. It was anticipated that the DOE would provide interim storage at centralized sites. In the meantime, sites took measures to extend their own storage capacity, often by replacing the storage racks in the pools with denser ones to extend capacity as. much as practical. When that was no longer sufficient, supplemental storage was acquired, typically as an independent facility, With additional delays in the development of the government's waste management system, plants shut down over the next ten years will have a full compliment of fuel in on-site storage and will need to address its disposition in planning for decommissioning. The NRC gives no specific guidance on managing or funding such storage. It does, however, refer a licensee to the provisions of 10 CFR 50.54(bb) (NRC 2001b), which require the licensee to submit for NRC approval the program by which it intends to manage and fund the management of all irradiated nuclear fuel at the reactor until possession transfers to the DOE. Whether funding is available as government reimbursements, damage claims, or through rate relief, the owner must determine the magnitude of potential financial liability.

Many activities must be performed just before or soon after a nuclear facility concludes its mission and enters the transition from operations to decommissioning. These activities include assurance of immediate and long-term safety for the facility systems, human resources challenges, systems configuration changes, regulatory changes, and stakeholder relations. Long-term stewardship and eventual site closure activities must also be considered and addressed.

Characterization is an essential and substantial part of decommissioning. An initial scoping survey must be done to identify personnel hazards and to develop a decommissioning plan. Detailed characterization data must be collected to determine the type and extent of contaminants before any actual decontamination or dismantling. Surveys must be done during decontamination to test the effectiveness of the efforts; they may be either the in-process type or post-decontamination, or both. A final status survey is required, and a confirmatory survey may also be required to document the facility end-state, In addition, should the facility be placed in some form of long-term or interim storage, it will be necessary to characterize the remaining radioactive material and hazardous chemical waste to support long-term stewardship requirements. Such extensive characterization efforts contribute substantially to the overall cost of a decommissioning project. No single technology can address the full spectrum of requirements for facility and material characterization. Decommissioning managers must identify the appropriate suite of characterization methods needed to thoroughly characterize the facility throughout the life of the project. Often, characterization methods are used in combination with one another to take advantage of the strengths and compensate for the limitations of each method. State-of-the-art characterization technologies show one or more of the following competitive discriminators: - Reduced labor to conduct the characterization activities - Improved data management, including automated generation of data reports - Practical application of standard laboratory practices in the field - Improved data accuracy, precision, and detection limits - Deployment of survey devices into inaccessible locations - Reduced radiation/chemical dose by using remotely deployed instruments - Improved operation - Reduced training and education requirements - Real-time or near real-time generation of data - The easily read data, and interpretation thereof - Acceptance of results by regulators