EPRI support of license renewal

During the early 1980's, the US utility industry recognized that Light Water Reactors (LWRs) could have a useful life substantially in excess of the current licensed term of 40 years service. These observations were confirmed by two plant specific studies and have led to a major initiative undertaken by EPRI and DOE to demonstrate the technical and institutional basis for a predictable, rational, and stable life extension option. The primary objective of the lead plants project is to establish and demonstrate, by the end of 1993, nuclear plant license renewal as a viable option. As part of this initiative, the lead plants project will result in a complete license renewal application to the NRC and will document the license renewal process for use by other utilities. A number of EPRI and DOE sponsored projects are providing technical support for the license renewal process. These projects are identifying deteriorating service environments for key components, systems, and structures and are establishing methods of assessing consequences and remedial actions. Other projects include economic evaluations and life cycle management assessment tools to address deterioration mechanisms. However, the principal means for providing technical support for license renewal is the generic Industry Reports (IRs), which as of October 1990, have all been submitted to the NRC for review. The IRs discussed in this paper are intended to identify and resolve key technical issues associated with extended operation of major LWR components, structures, and systems. The principle means of providing technical support for license renewal is the IRs whose objective is to document results of generic component, structure, or system evaluations to support life extension by addressing potential impacts of aging on components, structures, or systems as it relates to the plant's performance for extended service. Ten IRs on major components or systems have been completed and submitted to the NRC. The IRs show that the majority of component/degradation combinations are not significant for license renewal and that most of the remaining issues can be managed by current effective programs. EPRI expends a significant portion of its R and D funding in support of residual life assessment and age-related degradation management. The guidelines, techniques, and methodologies developed in EPRI programs are used extensively throughout the IRs as some of the effective programs for the management of age-related degradation mechanisms