Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Lessons learned from the Maintenance Rule implementation at Northeast Utilities operating plants

Conference ·
OSTI ID:251006
 [1];  [2];  [3]
  1. Maintenance Engineering Services, Waterford, CT (United States)
  2. Northeast Utilities, Berlin, CT (United States)
  3. ERIN Engineering and Research Inc., Walnut Creek, CA (United States)

The Maintenance Rule as described in 10CFR50.65 requires holders of all operating nuclear power plants to monitor the performance of structures, systems, and components (SSCs) against licensee-established performance criteria. The Industry with the assistance of the Nuclear Energy Institute (NEI) developed a guideline, which includes all parts of the Maintenance Rule, to establish these performance criteria while incorporating safety and reliability of the operating plants. The NUMARC 93-01 Guideline introduced the term ``Risk Significant`` to categorize subsets of the SSCs which would require increased focus, from a Maintenance Rule perspective, in setting their performance criteria. Northeast Utilities Company (NU) operates five nuclear plants three at Millstone Station in Waterford, Connecticut; the Connecticut Yankee plant in Haddam Neck, Connecticut; and the Seabrook Station in Seabrook, New Hampshire. NU started the implementation process of the Maintenance Rule program at its five operating plants since early 1994, and have identified a population of risk significant SSCs at each plant. Recently, Northeast Utilities` Maintenance Rule Team re-examined the initial risk significant determinations to further refine these populations, and to establish consistencies among its operating units. As a result of the re-examination process, a number of inconsistencies and areas for improvement have been identified. The lessons learned provide valuable insights to consider in the future as one implements more risk based initiatives such as Graded QA and Risk-Based ISI and IST. This paper discusses the risk significance criteria, how Northeast Utilities utilized NUMARC 93-01 Guideline to determine the risk significant SSCs for its operating plants, and lessons learned. The results provided here do not include the Seabrook Station.

OSTI ID:
251006
Report Number(s):
CONF-960306--; ISBN 0-7918-1226-X
Country of Publication:
United States
Language:
English

Similar Records

Lessons learned from early implementation of the maintenance rule at nine nuclear power plants
Technical Report · Thu Jun 01 00:00:00 EDT 1995 · OSTI ID:87033

The role of PRA in implementing the maintenance rule
Conference · Thu Dec 31 23:00:00 EST 1992 · Transactions of the American Nuclear Society; (United States) · OSTI ID:6022643

Risk-based selection of SSCs at Peach Bottom
Conference · Thu Dec 31 23:00:00 EST 1992 · Transactions of the American Nuclear Society; (United States) · OSTI ID:5818678