ML15238A097
| ML15238A097 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 06/15/1995 |
| From: | Wiens L NRC (Affiliation Not Assigned) |
| To: | Hampton J DUKE POWER CO. |
| References | |
| REF-GTECI-MI, REF-GTECI-SC NUDOCS 9506280522 | |
| Download: ML15238A097 (12) | |
Text
Mr. J. W. Hampton June 15, 1995 Vice President, OconWSite Duke Power Company P. 0. Box 1439 Seneca, SC 29679
SUBJECT:
AUDIT REPORT OF OCONEE USI A-46/IPEEE IN-PROGRESS SEISMIC WALKDOWN
Dear Mr. Hampton:
During the week of April 17, 1995, a team of three NRC technical staff, two from NRR and one from RES and two, contractors from Brookhaven National Laboratory, conducted an'audit of the USI A-46/IPEEE in-progress seismic walkdown activities conducted by your staff. The objective of the audit was to observe and assess the effectiveness of your process for identifying seismic concerns with the safeshutdown electrical and mechanical equipment.
The audit did not focus on the evaluationof seismic adequacy of equipment, which will be done 'after the submittal,of the IPEEE and A-46 evaluation reports to the NRC.
Therefore, it did not,cover the full extent of the necessary NRC staff's effort to reach closure on these two programs. The information gathered during the walkdown will assist the NRC staff in evaluating your staff's'and The industry's effectiveness in implementing the Generic Implementation Procedures- (GIP) developeifby the Seismic Qualification Utility Group (SQUG) and previously approved by the NRC. Enclosure 1 lists the attendees at, the entrance and exit meetings conducted at the site. provides the details of the audit results.
The audit team successfully accomplished its objectives of assessing the effectiveness of yourtstaffin its seismic walkdown activities and gathering information concerning the practice in use at Oconee in implementing the generic guidance. The cooperation ofoyour staff in assisting the audit team was greatly appreciated and"'sgni'ficantly"contributed to the success of the audit. If you have questions regarding the enclosed audit report, contact me at (301) 415-1495.
Sincerely,
/s/
L. A. Wiens, Senior Project Manager Project Directorate 11-2 Division of Reactor Projects-I/II Office of Nuclear Reactor Regulation Docket Nos. 50-269, 50-270, and 50-287
Enclosures:
- 1. Attendance Lists
- 2. Audit Report cc w/encls:
See next page DISTRIBUTION
PD22 Reading File R. Wessman R. Crlenjak, RII PUBLIC M. Drouin E. Merschoff, RII J. Zwolinski P. Y. Chen S. Varga DOCUMENT NAME: G:\\OCONEE\\SQUTRIP.LTR To receive a copy of this document, Indicate In the box: "C" = Copy without attachment/enclosure "E"
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PM:PD22:DRPfE D:PD22:DRPE NAME LBerry t
LWiens:dt HBerkow 11 DATE 6/
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-W001 June 15, 1995 Mr.
. Hampton Vice President,. Oconee Site Duke Power Company P_ 0,. Box 1439 Seneca, SC 29679
SUBJECT:
AUDIT REPORT OF OCONEE USI A-46/IPEEE IN-PROGRESS SEISMIC WALKDOWN
Dear Mr. Hampton:
During the week of April 17, 1995, a team of three NRC technical staff, two from NRR and one from RES and two contractors from Brookhaven National Laiboratory, conducted an audit of the USI A-46/IPEEE in-progress seismic waikdown activities conducted by your staff. The objective of the audit was to observe and assess the effectiveness of your process for identifying seismic concerns with the safe shutdown electrical and mechanical equipment.
The audit did not focus on the evaluation of seismic adequacy of equipment, which will be done after the submittal of the IPEEE and A-46 evaluation reports to the NRC. Therefore, it did not cover the full extent of the necessary NRC staff's effort to reach closure on these two programs. The information gathered during the walkdown will assist the NRC staff in evaluating your staff's and the industry's effectiveness in implementing the Generic Implementation Procedures (GIP) developed by the Seismic Qualification Utility Group (SQUG) and previously approved by the NRC.
Enclosure I lists the attendees at the entrance and exit meetings conducted at the site. provides the details of the audit results.
The audit team successfully accomplished its objectives of assessing the effectiveness ofyour staff in its seismic walkdown activities and gathering in-formation concerning the practice in use at Oconee in implementing the generic guidance. The cooperation of your staff in assisting the audit team was greatly appreciated and significantly contributed to the success of the audit. If you have questions regarding the enclosed audit report, contact me at,(301) 415-1495,.
Sincerely, L. A. Wiens, Senior Project Manager Project Directorate 11-2 Division of Reactor Projects-I/II Office of Nuclear Reactor Regulation Docket Nos. 50-269, 50-270, and 50-287
Enclosures:
I. Attendance Lists
- 2. Audit Report cc,w/encls: See next page
Mr. J. W. Hampton Duke Power Company Oconee Nuclear Station cc:
A. V. Carr, Esquire Mr. Ed Burchfield Duke Power Company Compliance 422 South Church Street Duke Power Company Charlotte, North Carolina 28242-0001 Oconee Nuclear Site P. 0. Box 1439 J. Michael McGarry, III, Esquire Seneca, South Carolina 29679 Winston and Strawn 1400 L Street, M.
Ms. Karen E. Long Washington, DC 20005 Assistant Attorney General North Carolina Department of Mr. Robert B. Borsum Justice B&W Nuclear Technologies P. 0. Box 629 Suite 525 1700 Rockville Piike Rockville, Maryland 20852-1631 Mr. G. A. Copp Licensing -
ECO50 Manager, LIS Duke Power Company NUS Corporation 526 South Church Street 2650 McCormick Drive, 3rd Floor Charlotte, North Carolina 28242-0001 Clearwater, Florida 34619-1035 Dayne H. Brown, Director Senior Resident Inspector Division of Radiation Protection U. S. Nuclear Regulatory Commission North Carolina Department of Route 2, Box 610 Environment, Health and Seneca, South Carolina 29678 Natural Resources P. 0. Box 27687 Regional Administrator, Region II Raleigh, North Carolina 27611-7687 U. S. Nuclear Regulatory Commission 101 Marietta Street, NW. Suite 2900 Atlanta, Georgia 30323 Max Batavia, Chief Bureau of Radiological Health South Carolina Department of Health and Environmental Control 2600 Bull Street Columbia, South Carolina 29201 County Supervisor of Oconee County Walhalla, South Carolina 29621
ENCLOSURE 1 OCONEE IN-PROGRESS SEISMIC WALKDOWN LISTS OF MEETING ATTENDEES Entrance Meeting on April 17. 1995 NAME GROUP/TITLE Judy E. Smith Reg Group/Tech Specialist Raymond L. McCoy MCE/Sr. Engr.
Darryl A. Kelley MCE/Engr. Sup II J. E. Burchfield Reg Comp/Reg. Comp. Manager Len Wiens NRC/NRR John T. Chen NRC/RES John S. Ma Structural Engineer/NRC Daniel D. Kana Inst. Eng./SwRI (NRC Contr.)
J. W. Hampton VP/ONS Bill Foster 0NS/SA Barry Millsaps ONS/MCE Paul Harmon NRC Resident Lee Keller NRC Resident Pei-Ying Chen NRC/NRR/DE Exit Meeting on April 20, 1995 NAME GROUP/TITLE J. E. Burchfield Reg. Comp. Manager D. A. Kelley Engr. Supervisor L. B. Elrod R. P. Childs Senior Engineer R. V. Hesterr Engineer B. K. Millsaps MCE R. L. McCoy MCE J. S. Ma Joe M. avi Structural Engineer/NRC Joe M. Davis Engineer Manager J. W. Hampton V/N Daniel D. Kana V/N Danil D.KanaInst. Eng./SwRI (NRC Co'ntr.)
Kamal Bandyopadhyay BNL (NRC Contr.)
Len Wiens NRC/NRR/PM Judy E. Smith ONS/Reg. Comp P. Y. Chen NRC/NRR/DE
ENCLOSURE 2 INPAUDIT REPORT ON USI A-46/IPEEE IN-PROGRESEISMIC WALKDOWN AT OCONEE INTRODUCTION The licensee of the Oconee Nuclear Power Plant is currently implementing the USI A-46 program using the procedures developed by the Seismic Qualification Utilities Group (SQUG) and documented in the Generic Implementation Procedure (GIP), Rev. 2 (Reference 1).
An audit of the licensee's A-46 implementation program was performed at the site on April 17-20, 1995, using the guidence in Attachment A (Attachment 4 of Reference 2, USI A-46 and IPEEE Coordination Plan).
The purpose of the audit was to observe the licensee's equipment walkdown activities and assess whether the licensee is reasonably implementing the criteria and procedures delineated in the GIP and the NRC Supplemental Safety Evaluation Report (Reference 3).
The major focus of the site visit was to audit the licensee's walkdown of selected equipment items. In addition, a review of the qualification of the licensee's seismic review team (SRT) and the A-46 equipment selection procedure and screening evaluation work sheets (SEWS) was performed. The licensee has combined its USI A-46 walkdown effort with that for the seismic portion of the Individual Plant Examination of External Events (IPEEE) program. This report provides the results of the audit as observed by the NRC audit team. In addition to the Oconee Project Manager, the audit team included the following technical members:
Pei-Ying Chen - Team Leader, Mechanical Engineering Branch, NRR John S. Ma - Civil Engineering & Geosciences Branch, NRR S
John T. Chen -
Probabilistic Risk & Analysis Branch, RES (part-time)
- Kamal Bandyopadhyay -
Contractor, Brookhaven National Laboratory
- Daniel Kana -
Contractor, Southwest Research Institute QUALIFICATION OF LICENSEE'S SEISMIC REVIEW TEAM During the audit, the following licensee personnel performed the walkdown and provided information to the NRC audit team:
Ray McCoy (Structural/Seismic)
Rusty Childs (Structural/Seismic)
Brant Elrod (Structural/Seismic)
Bob Hester (Mechanical/Structural/Seismic)
Ray Nix (Operational)
The audit team was informed that Messrs. McCoy, Childs, Elrod and Hester from the licensee's staff possess professional engineering licenses and that they have attended the A-46 training course offered by the SQUG. In addition, the following personnel interfaced with the NRC audit team in their respective roles in conjunction with the walkdown effort:
Steve Nader (Systems)
Darren Woods (Systems)
Farrel Moss (Electrical)
2 It was reported that the SRT is being assisted by a few other engineers most of whom are SQUG trained.
The qualification of the licensee's SRI exceeds the minimum qualification required by the GIP. Moreover, through interaction during the audit, the SRit was found to have background in the structural and seismic disciplines and to be well qualified in the application of the GIP provisions.
Furthermore, the SRI was well organized in performing the walkdown (e.g., reviewing available equipment information prior to walkdown; examining equipment and taking notes during walkdown; maintaining retrievable equipment and walkdown data; etc.).
EQUIPMENT SELECTION The licensee has identified 1411 equipment items for implementation of A-46 and IPEEE programs at the three Oconee units, not including the equipment in the Keowee hydroelectric power facility which supplies the emergency power for the three units in case of a loss of offsite power. Because of the limited scope of the audit, the staff had informed the licensee prior to the trip that it would not perform the relay and system engineering reviews during the site visit which in turn precluded an audit of the Keowee facility.
The staff noted that the identification of the equipment items was performed in accordance with the safe shutdown path selected to accomplish the essential safe shutdown functions as described in the GIP. The system engineers first identified the necessary mechanical equipment items from the equipment flow chart. The electrical engineers identified the electrical and control equipment items necessary for the selected mechanical equipment items to perform their functions. Additional equipment was identified in consultation with other documents, such as the Emergency Operating Procedures, to select items that monitor and 'control the reactor environment.
Although the audit team did not perform a system engineering review to determine the adequacy of the selected equipment items to achieve the shutdown functions, the overall procedures adopted by the licensee appear to be in conformance with the GIP. The potential weakness that was observed by the audit team was the apparent reliance on the competence/experience of the system engineers rather than the use of defined procedures to determine the completeness of the necessary equipment list. It was not clear whether this was due to the lack of complete instructions in the GIP.
EQUIPMENT WALKIJOWN The licensee had completed their walkdowns of a majority of the equipment items required for safe shutdown prior to the audit. During the audit, the SRI performed walkdowns of the following equipment items:
- 1.
HBP Blanket Panel (2SA-1O and 11)
- 2.
Motor Control Center (2XA)
- 3.
Wall-Mounted Small Breaker Panel (2FDW-372)
- 4.
Switchgear (2TE)
- 5.
Wall-Mounted Small Breaker Panel (3KG)
- 6.
Switchgear (one bay of 2TC)
0 0
3
- 7.
Instrument Rack (2PIR), Instrument 2RCIS
- 8.
Miscellaneous Termin), Cabinet (2MTCI)
- 90.
Engiedered efaj Relay Cabinet (2ESTC3)
II. Panel Board Mounted on Unistrut (2KRA)
The SRT took notes Of the as-built configurations of the equipment items (e-g., overall-dimension intenals(alhoug e i,
Lopened cabinet doors to visually inspect the anchorage as much as quipment was energized) verified the exisece of checked relay moun Possible, checked potential i
te actence of G hP b ud i relay econt ing, and fo llow ed the "c ave at " list o f i te ract ionp sp o t GIP bounding spectrum approach was being used, on l theia re vn t c v a s w r considered). TeSTapocwabenusdonihtfthe GIP. (Since the sice e d) ad The SRT was able to efficiently e xmne tomele tvheceqepme re Ofianceiou had oeknowleg of th equipment prior to the walkdown as a result sof ateios waovewel osimilar equipment in other units.
The walkdown of some of the above eleven items was incomplete (e.g., collection of data to evaluate anchorage strength). The audit team learned that the SRT plans to per 'form a future walkdown to collect further information.
The licensee's walkdown was found to be detailed and consistent with the GIP approach.
The SRT demonstrated an honest effort to collect information in spite of inaccessibility problems.
EQUIPNENT EVALUATION Further discussions of the walkdown items were held in the office. The SRT plans to use information obtained for similar equipment from previous walkdown and evaluations.* For the eleven walkdown items, the licensee's team obtained most of the information necessary to prepare the SEWS. The staff did not observe the licensee's performance of calculations for equipment anchorages during this audit. Several potential interaction problems were identified and further evaluation by the licensee will be required for their resolution. In some instances, field modifications could be expected.
In addition to the above eleven i temsexamined during the audit, the SRT presented a sample SEWS of previously completed equipment verification including some anchorage calculations (MCCs 2DCA, 2XB and IMVC2; Pump ICCPUOQ2; Tanks 2LPIHXOOQA, lSFTKO02 and 1LPIHOOQQQ; Switchgear 1B1T and 1CRDS; and Instrument Panel 3ADA).
The approach in general follows the GIP procedures and criteria.
STATUS AND DOCUMENTATION The licensee is continuing its A-46 program (in combination with other programs, e.g., IPEEE, updating PRA, etc.). Many equipment items have been identified as outliers mostly because of inadequate anchorage, potential spacial interaction concerns, or their absence from the GIP equipment classes.
Formal documentation that will be submitted to the NRC has not yet been completed for any unit.
The licensee stated that a third-party audit of the Oconee A-46IpEEE results will be performed by eight to ten individuals, some of whom will be "in-house" personnel who have not been involved directly in the A-46/IPEEE implementation programs for 'Oconee units. The licensee feels
4 that an advantage of this approach is that such personnel are much more familiar with the plant-specific equipment than would be the case with contracted personnel.
AUDIT OBSERVATIONS Several observations were made during the audit. Since the work is still in progress, most of these observations are general in nature, as they were noted from various aspects of the audit, such as observations of walkdowns and reviews of SEWS and related documents. Many of the observations are generic in that, in spite of the dedicated effort by well-qualifie personnel (the majority of whom have received the SQUG training course), some of the SRT's interpretations and applications of certain GIP criteria may be questionable.
This may be due to insufficient or unclear guidance in the GIP that may also apply to the A-46 program implementation at other nuclear plants.
mThe following observations were noted by the audit team and do not include earlier observations concerning personnel qualification, equipment selection, walkdown, evaluation, and documentation issues that were discussed above.
I.
During the walkdown the staff observed that the licensee performed a tightness check on all concrete expansion anchor bolts and re-tightened all the anchors by turning the nuts in accordance with the GIP requirements. The licensee measured the location, length and thickness of all welds that served as anchorage to the equipment.
The staff reviewed sample calculations of equipment anchorage which had been completed in the previous walkdown and evaluated by the SRT. The review results indicate that the licensee was familiar with the anchorage criteria and procedures delineated in the GIP and exhibited a good judgement in its evaluations.
- 2.
The GIP allows the exercise of considerable judgement in conforming to the GIP criteria or meeting their intents, and in declaring outliers.
The licensee is rightfully using such judgements. But, some of the licensee's interpretations of the GIP criteria in meeting their intents may be questionable The GIP criteria (e.g., class descriptions, caveats, etc.) were developed over a long period considering reviews and results of a large number of studies of applicable experience data. The bases of the GIP criteria may not be obvious to the users.
Therefore, the licensee needs to be cautious in interpreting the criteria. This becomes more important when a criterion is not satisfied and the licensee decides instead that the intent of the criterion is met.
- 3.
When the GIP criteria (e.g., class descriptions) are not satisfied, the licensee is accepting the deviation as long as the anchorage can transfer the load. This is an oversimplification of the GIP criteria and may overlook the equipment details that can influence its functionality.
- 4.
The term "relay" has been used in the GIP to mean devices sensitive to contact chatter including contactors, switches, motor starters, etc.
5 This definition may not have been clear to the licensee probably due to insufficient guidance in the GIP. For example, Section 4 and other sections of the GIP that the SRT uses for equipment' seismic adequacy verification do not seem to be clear in this respect although it is defined in Section 6 (Relay Functionality Review).
- 5.
The licensee is using guidelines that were not reviewed by the NRC staff (e.g., "Guidelines for Estimation or Verification of Equipment Natural Frequency," EPRI Report TR-102180, March 1993; computerized database containing equipment items that may not meet the GIP equipment class description). This may lead to the licensee's acceptance of equipment parameters that may be outside the GIP "boundaries."
- 6.
In general, a multi-bay electrical cabinet assembly is connected at the bottom with a steel channel.
The channel, in turn, is welded or bolted to the embeded steel to serve as anchorage to the cabinet assembly. Too long spacings of anchorage (bolts or welds) of a cabinet assembly were considered acceptable by the SRT possibly due to lack of guidance in the G IP.
- 7.
There is a potential for confusion concerning equipment that is physically labeled "safety-related," and equipment that is included in the A-46 safe shutdown equipment list. This gives an impression that the "safety-related" and the non-safetygrade equipment identified in the A-46 safe shutdown equipment list may be maintained differently.
Moreover, it is not clear what procedures are being implemented to ensure that the A-46 equipment items will remain functional after the completion of the A-46 program implementation.
This seems to be a potential generic issue since the GIP does not appear to provide any guidance in this regard.
- 8.
The licensee currently seems to consider 14-inch deep motor control centers to be within the GIP equipment class.
But, the class description provided in the GIP specifies the depth of the motor control centers to be between 18 and 24 inches.
- 9.
At Oconee, many electrical cabinets are mounted through elastomeric pads. This may require special considerations that were not included in the GIP.
- 10.
Estimation of the fundamental natural frequency of equipment is a particularly complicated procedure. The licensee may need to prepare documentation of the basis for its frequency estimates.
On balance, the licensee's activities were conducted in general conformance with the GIP provisions. The licensee's SRT was found to be well qualified in the application of the GIP provision. However, as cited above, because there are areas in the GIP that require considerable judgements, the staff found some of the interpretations and applications of certain GIP criteria may be questionable. The audit team's observations were conveyed to the licensee's SRT, and the audit team pointed out that no specific action was being required by the staff.
The staff's final determination on the adequacy of
6 implementation of both programs at Oconee will be based on the review of the final summary reports.
IPEEE PROGRAM The Oconee plant is identified as an outlier plant in the resolution of the Charleston Earthquake issue. The IPEEE process will be used to resolve the safety concern of the seismic portion of the IPEEE program at Oconee. The licensee also uses EPRI's seismic margin method (EPRI Report NP-6041) to assess the equipment capacity in addition to updating its existing seismic PRA.
The licensee estimated that about 94 percent of the IPEEE equipment scope is included in the USI A-46 safe shutdown equipment list. The audit team was informed by the licensee that all equipment within the scope of IPEEE are screened during the plant-specific walkdowns using the IPEEE Review Level Earthquake as specified in NUREG-1407 and the procedures specified in the GIP and EPRI NP-6041. This is acceptable to the staff. The results of the licensee's evaluation will be reviewed by the staff after the licensee submits its IPEEE report.
One area of potential staff concern was noted when the licensee indicated that the deconvolution process was used in the new seismic analysis for Oconee IPEEE program. The preliminary result of the new seismic analysis showed that the ground motion, defined to be the median NUREG/CR-0098 spectrum anchored at 0.3g at free field, was reduced to the median NUREG/CR-0098 spectrum anchored at approximately 0.18g at the foundation (higher than the SSE for Oconee USI A-46 program, which is the Housner spectrum anchored at 0.1g). Because the Oconee plant was founded on rock and the overburden is shallow, the use of deconvolution process for such condition is questionable. A staff review of the aspects related to the deconvolution process will be conducted when the licensee submits its IPEEE report.
REFERENCES
- 1.
"Generic Implementation Procedures (GIP), Revision 2," Seismic Qualification Utilities Group (SQUG), February 14, 1992.
- 2.
"USI A-46 and IPEEE Coordination Plan," USNRC, March 14, 1995.
- 3.
"U.S. NRC Supplemental Safety Evaluation Report No. 2 on Generic Implementation Procedure," May 22, 1992.
Attachment:
Attachment A-Combined NRR/RES Audits of USI A-46/IPEEE
ATTACHMENT A COMBINED NRR/RES AUDITS OF USI A-46/IPEEE LICENSEES' IN-PROGRESS SEISMIC WALKDOWN ACTIVITIES Objective Perform site audits of USI A-46/IPEEE licensees' in-progress seismic walkdown activities to assess licensees' effectiveness in identifying seismic concerns with USI A-46/IPEEE safe shutdown electrical 'and mechanical equipment, including the equipment supports and anchorages. The specific areas that will be examined during the audit will depend on activities being conducted by licensees of selected facilities at that time.
Scope Of Audit Activities The audit team will observe the licensees' walkdown activities of safe shutdown electrical and mechanical equipment in order to assess whether the licensees are reasonably implementing the criteria and procedures delineated in the Generic Implementation Procedure, Revision 2 (GIP-2) and staff's Supplemental Safety Evaluation Report No. 2 dated May 22, 1992. The specific audit activities will include the following:
(1) verifying the qualifications of the licensees' seismic walkdown team members; (2) observing the licensees' walkdown inspections of selected safe shutdown electrical and mechanical equipment; (3 ) reviewing a sample of completed equipment walkdown packages in accordance with the guidance provided in the Temporary Instruction (TI 2515/124, Attachment 3); and (4) assessing the effectiveness of the licensees' activities insofar as identifying and resolving equipment seismic concerns with focus on equipment anchorage and seismic interactions. Prior to the audit, the staff will discuss with the licensee the activities that may be observed and a plant-specific audit plan will be prepared. Plant-specific audit reports will be issued describing the items which were reviewed/observed, and the staff's assessments of the licensees' activities.
This part of the audit may not be possible if the licensee does not maintain the completed equipment walkdown packages at the plant site.
Audit Team Composition The audit team will consist of up to four members selected from NRR, Research and contractors, with mechanical/structural backgrounds. The specific team composition will vary depending on the specific walkdown activities which will be observed during the site audit. The NRR member will be designated as the team leader.
Audit Schedule Each site audit may require up to 5 days depending on the specific licensee activities which will be observed. In general, the audit schedule will be as follows:
2 Day 1 Travel/Badging/Entrance Days 2-4 Audit in-progress walkdown activities, and, if possible sample audit completed walkdown packages.
Day 5 Exit/Travel Prerequisite Knowledge/Training The audit team members should have mechan.ical/structural engineering backgrounds, and knowledge of traditional equipment anchorage and seismic interaction concerns. In general, the audit team as a whole should have in depth knowledge of both the USI A-46 and IPEEE program and related criteria/guidance documents, such as GIP-2 and EPRI NP-6041.
Candidate Facilities for NRC Audit Based on available walkdown dates provided by licensees, the two facilities likely to be targeted for the in-progress seismic walkdown will be selected from the following candidate plants:
Peach Bottom 2 & 3; Browns Ferry 3; Oconee 1, 2 or 3; Quad Cities 1; Vermont Yankee and Duane Arnold.