ML16172A069
| ML16172A069 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 06/16/2016 |
| From: | Glenn Dentel Reactor Projects Branch 2 |
| To: | Corcoran W - No Known Affiliation |
| Dentel G | |
| References | |
| Download: ML16172A069 (1) | |
Text
ML16172A069 From:Dentel,Glenn Sent:Thursday,June16,20164:32PM To:DRWILLIAMCORCORAN
Subject:
RE:Re:UCSboltassessmentofoperability Dr. Corcoran, I am responding to your email dated June 8, 2016 (ML16168A073). In that email, you raised several questions regarding baffle-former bolting conditions at Indian Point.
The NRC has published a webpage dedicated to baffle-former bolts at nuclear power plants, which provides information on this subject including a background on the issue, safety implications, and the NRCs next steps. For many answers to your questions, please visit our page at http://www.nrc.gov/reactors/operating/ops-experience/baffle-former-bolts.html.
Baffle bolt degradation and failures were first identified in foreign reactors as early as 1988. In response, the NRC issued generic communication to owners of U.S. plants when this condition was first discovered and ensured it was addressed in plants in the U.S. as part of our license renewal reviews. Baffle bolt degradation has also been identified in the United States at D.C.
Cook, H.B. Robinson, Point Beach and Prairie Island, among others, but to a more limited extent than that detected at Indian Point Unit 2. The owners of Indian Point Unit 2 identified the baffle bolt problems by completing the required examinations as a result of our license renewal reviews for these plants.
When Indian Point Unit 2 observed visual indications of bolting problems during its recent refueling outage, the on-site NRC resident inspectors were made aware of the problem and began to follow the issue closely. Inspectors trained in materials science issues from the NRC Region I Office and NRC headquarters staff completed on-site inspections to observe bolt replacement activities, critically reviewed the licensees technical evaluations regarding bolt replacement controls and supporting analyses, and discussed in detail the results of our reviews. Our inspectors also reviewed the licensees evaluation of this information as it pertains to Indian Point Unit 3. While our reviews and inspections continue in this regard, we do not have any immediate safety concerns.
Our inspection results, which will include the NRCs assessment of Indian Point Units 2 and 3, will be provided in an upcoming publicly available inspection report by August 15, 2016. I will reach out to you once the report for Indian Point becomes available and confirm that all of your questions have been answered.
Sincerely, Glenn Dentel, Chief Division of Reactor Projects Branch 2