ML20044F946
| ML20044F946 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 04/26/1993 |
| From: | Virgilio M Office of Nuclear Reactor Regulation |
| To: | Sniezek J NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO) |
| Shared Package | |
| ML20044F925 | List: |
| References | |
| NUDOCS 9306010245 | |
| Download: ML20044F946 (4) | |
Text
.
pm8tcgh UNITED STATES t
., +[
$/
j NUCLEAR REGULATORY COMMISSION 1
'f WASHINGTON, D.C. 205564001
,\\$',b'/
April 26,1993 MEMORANDUM FOR:
James H. Sniezek Deputy Executive Director for Nuclear Reactor and Regulation, Regional Operations and Research FROM:
Martin J. Virgilio, Assistant Director for Regions IV & V Reactors Division of Reactor Projects III/IV/V Office of Nuclear Reactor Regulation
SUBJECT:
BRIEFING 0F CONGRESSMAN DeFAZIO ON TROJAN The purpose of this memo is to provide my response to the ouestions contained in your April 23, 1993 memo to me.
For completeness I have included the three questions.
I. Were you aware of the of the 12/23/91, J. Hopenfeld DP0 at the time of the briefing?
Yes.
I became aware that a staff member in the NRC's Office of Research had raised concerns to his management before we met with Congressman DeFazio on February 5,1992.
- 2. Were you aware of any other staff in RES or NRR that had a different view from the agency approach at the time of the briefing?
No.
I was not aware that any other staff members had a different view from the agency approach at the time of the briefing.
- 3. If the answer to question 1 or 2 is yes, why was this not identified to Congressman DeFazio at the time of the briefing?
I did not consider the staff member's concern in either the pre-paration for or the delivery of the presentation.
In hindsight, I believe it was not considered because I did not view the concern significant enough to bring to the Congressman's attention.
In the Spring of 1991, I was serving as an Assistant Director in the Division of Reactor Projects, Office of Nuclear Reactor Regulation (NRR), responsible for managing all projects activities for Regions IV and V.
Ted Quay was the Project Director responsible for supervising projects activities for Region V.
Roby Bevan was the Project Manager assigned to Trojan. Because of the potential safety significance and level of internal (NRC) and external interest, a large number of NRC managers and staff were involved in the oversight of the Trojan steam generator program.
9306010245 930510 PDR ADDCK 05000344 P
James H. Sniezek,
Steam generator tube inspections conducted at the Trojan plant by Portland General Electric Company (PGE or the licensee) during the Spring 1991 outage revealed a number of degraded tubes. The licensee used an eddy current bobbin probe to inspect the hot leg side of all tubes in each steam generator. A 20% sample of tubes in one steam generator were also inspected over the full length of the tubes using the bobbin probe. The licensee utilized the more sensitive motorized rotating pancake coil (MRPC) probe to confirm and better characterize the indications found with the bobbin probe.
The licensee began pulling tubes in June 1991, to assess the degradation mechanisms and accuracy of their eddy current inspec-tion techniques. Examination of the pulled tubes revealed the presence of axial micro-cracks apparently as a result of two mechanisms IGA (intergranular attack) and IGSCC (intergranular stress corrosion cracking). Destructive tests demonstrated acceptable levels of structural integrity associated with tubes exhibiting micro-cracks. However, the pulled tube examinations called into question the accuracy of the inspection program and prompted the licensee to reassess the data from the inspections they had completed, reclassify some of the indications and conduct more inspections using the MRPC probe.
In September and October 1991 the licensee removed additional tubes. The results of the examinations and tests appeared to confirm previous results. Again, examination of the pulled tubes prompted the licensee to reassess the data from the inspections and reclassify some of the indications. At that point in' time NRC interest in the project led to numerous conference calls to exchange information.
In early October the NRC staff conducted a noticed, open meeting with the licensee at the Headquarters Offices to discuss the Trojan steam generator program. At the conclusion of the meeting the licensee delineated its action plan to provide the results of pulled tube data, respond to questions the staff had asked on water chemistry, and submit a final report to the staff summarizing their assessment.
In late October 1991, I provided a briefing to the State's Energy Facility Sighting Council on the status of HRC's review of the Trojan steam generator program at one of their open meetings in the Portland area.
In early November 1991, Roby Bevan was reassigned to the Cooper project and Lawrence Kokajko was assigned as the Trojan Project Manager. At that point in time the Region V Administrator, Jack Martin, visited the Trojan site and NRR's Executive Team requested the staff to develop an action plan for overseeing the licensee's assessment of the Trojan steam generators. During that time period conference calls with the licensee continued the exchange of technical information. On November 6, 1991 the NRC staff, EPRI
)
James H. Sniezek,
and Westinghouse gave extremely detailed technical presentations to the ACRS (subcommittee) on steam generators.- Much of the information presented came from the Trojan steam generator program. On November 8,1991, Tom Murley, the Director of NRR, visited the Trojan site.
In mid-November an NRC inspection team conducted an on-site assessment of the Trojan steam generator program. The licensee pulled an additional five tubes in November of 1991. The purpose for pulling tubes was to provide additional information on the structural integrity of tubes with meiro-cracks.
Inspections and tests of these tubes provided additional data confirming the accuracy of the inspection program and the acceptability of structural margins remaining in the tubes.
In mid-December 1992, the NRC staff held a noticed, open meeting with the licensee at the Trojan site to discuss the results of the steam generator program. Headquarters and Region management and staff, including Jack Martin, Bill Russell, Jim Richardson and I spent two full days in technical discussions with the licensee and their consultants.
Discussions addressed, in detail, the accuracy of the licensee's eddy current inspection program, the acceptance criteria, the root cause of the tube degradation, and the safety margins associated with the licensee's proposed acceptance criteria.
Throughout the month of January 1992, NRR's technical experts reviewed data and analyses submitted by the licensee to support a technical specification change request to modify the steam generator tube inspection acceptance criteria.
In mid-January NRC technical staff members briefed Commissioners and their staffs on the Trojan steam generator program, steam generators at other facilities and the status of NRC's review of generic industry proposals related to steam generator programs. During this time period the State's representatives, David Steward-Smith and Adam Bless, were extensively involved in the Trojan project. They made direct contact with members of the NRC staff to discuss various aspects of the Trojan steam generator program and the NRC's views on the related issues.
It was during that time period that Lawrence Kokajko advised me that a staff member in RES, J. Hopenfeld, had a differing professional view (DPV) related to steam generator tube inspection techniques.
In conversations with Lawrence Kokajko, I confirmed that RES management and NRR's technical staff were aware of the concerns. That was the only time I recall discussing a DPV related to steam generators before the Spring of 1992 when I learned that RES had proposed a new generic issue based on its evaluation of J. Hopenfeld's DPV.
Toward the end of January 1992, Trojan made its final submittal to the NRC on the steam generators and the technical staffs' assessment was completed. The staff found the licensee had used state-of-the-art inspection techniques. Although not all micro-cracks would be identified those of structural significance were detectable.
The staff
James H. Sniezek,
found the licensee had demonstrated adequate leakage integrity for the most challenging conditioa, the steam line break. Although there was a limited data set from the pulled tubes, the leak rate correlation incorporated conservatism relative to Trojan. The staff concluded that the licensee had demonstrated, with high confidence, that its proposed repair criteria ensured adequate structural integrity and was consistent with regulatory requirements and recommendations. We had received neither comments nor hearing requests challenging the licensee's proposal in response to the Federal Register notice.
The last week in January 1992, I learned that two Congressmen from Oregon had requested a briefing on Trojan. On February 6, 1992, Lawrence Kokajko and I briefed Congressmen Au Coin and DeFazio. The briefing we provided the Congressmen and their staff members included an overview of the licensee's safety performance including SALP results and enforcement history, an explanation of the design of the steam generators and the results of our review of the licensee's steam generator program and technical specification change request.
Later that same day we issued an amendment to Trojan's technical specifications accepting the licensee's proposed steam generatar inspection acceptance criteria.
I am available to meet with you should you desire any additional information on this subject.
Martin J.
irgilio, Assistant Director for Regions IV & V Reactors Division of Reactor Projects III/IV/V Office of Nuclear Reactor Regulation
_