NDTsi 2001 Session: Structural Integrity and NDE I-II
Recent Revisions to the U.S.N.R.C. Regulatory Program for Performing Steam Generator (SG) Inspections (1)
C. Khan, E. Sullivan, D. Coe, US NRC, USA
ABSTRACT
On February 15, 2000, a failure occurred in a steam generator (SG) tube at the Indian Point 2 (IP2) nuclear power plant in Buchanan, New York. The location of the failure was in a low row U-bend location. The reactor was safely shut down by the plant systems and operators. The event resulted in a minor radiological release to the environment that was well within regulatory limits. Because of the significance of the event and the level of interest it generated, an IP2 Lessons-Learned Task Group was formed to evaluate the NRC staff's regulatory processes related to assuring SG tube integrity in order to identify and recommend areas for improvements applicable to the NRC and/or industry. The Task Group concluded that the weaknesses in the SG program at IP2 that contributed to the poor condition of the failed SG tube had generic implications. While the now replaced IP2 SGs were the last of their particular model, Task Group review of other SG designs and tube materials indicated potential generic applicability of the IP2 lessons. Review of pressurized water reactor risk analysis confirms that SG tube integrity is important at all PWRs. Therefore, the Task Group concluded that a highpriority should be assigned to improvements in the SG tube integrity program at IP2, in the industry guidance on SG tube integrity programs, and in associated NRC regulatory programs. This paper will focus on the Task Group recommendations that deal with NRC oversight of licensee SG tube examination programs. As a result of those recommendations, NRC is enhancing its regulatory inspection program for assuring SG tube integrity, including its regulatory inspection program. This paper will discuss the role of industry in this program. It will discuss the Task Group recommendations related to the NRC inspection aspects of this program and will explain how the regulatory inspection program is being revised. The paper will also discuss how the SG regulatory inspection program fits under the relatively new NRC Reactor Oversight Process (ROP) and will provide basic information to explain the new Reactor Oversight Process. (1) USNRC steam generator inspections refer to the program conducted by the regulatory authority for overseeing the non-destructive examinations carried out by the US nuclear power plant operators.
Publication Source: 3nd International Conference on NDE in Relation to Structural Integrity for Nuclear and Pressurized Components, November 14-16, 2001, Seville Spain. Publisher: Tecnatom s.a. - [Homepage]
