IR 05000269/1989027
| ML15224A588 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 09/26/1989 |
| From: | Conlon T, Harris J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML15224A587 | List: |
| References | |
| 50-269-89-27, 50-270-89-27, 50-287-89-27, GL-86-10, NUDOCS 8910200013 | |
| Download: ML15224A588 (7) | |
Text
R RE UNITED STATES C,
NUCLEAR REGULATORY COMMISSION
REGION II
101 MARIETTA STREET, ATLANTA, GEORGIA 30323 Report Nos.: 50-269/89-27, 50-270/89-27, and 50-287/89-27 Licensee:
Duke Power Company 422 South Church Street Charlotte, NC 28242 Docket Nos.: 50-269, 50-270, License Nos.: DPR-38, DPR-47, and and 50-287 DPR-55 Facility Name:
Oconee 1, 2, and 3 Inspection Conducted:
August 21-22, 1989 Inspector:____e.,je'
t J R. Harris Date Signed Approved by:
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f f em er t 757 T. E. Conlon, Chief Oate Signed'
Plant System Section Engineering Branch Division of Reactor Safety SUMMARY Scope:
This special, announced inspection was conducted in the areas of open items in fire protection at the Oconee nuclear plan Results:
In the areas inspected, violations or deviations were not identifie The licensee was very cooperative in assisting the inspector in the resolution of these item REPORT DETAILS 1. Persons Contacted Licensee Employees
- S. Christopher, Analytical Engineer
- T. Kelly, Fire Protection Supervisor
- E. Legette, Compliance
- D. Swigart, Operations Supervisor NRC Resident Inspectors
- Skinner
- Attended exit interview 2. Independent Inspection (64704)
Region II sent a letter to NRR dated March 9, 1989, requesting that they clarify existing fire protection criteria pertaining to fire brigade training and requests for offsite fire department assistanc The concerns were, do NRC guidelines stipulate that the training of plant fire brigades include practice on "live fires" involving energized equipmen Also, does NRC require that licensees request the assistance of offsite fire departments for fires inside the plan These issues arose in conjunction with the investigation of the fire and reactor trip at the Oconee Nuclear Station, Unit 1, on January 2 and 3, 198 NRR response to this item was that the licensee should be conducting training of the fire brigade on energized electric equipmen They also concluded that the licensee is not required to summon offsite assistance during a fir However, they indicated that planning should be in place, including periodic training, to facilitate the response by local fire departments if offsite assistance is deemed necessary to respond to a fire at the plan The inspector reviewed training records on "live fires" involving energized electric equipment conducted January 23, 1989, February 20, 1989, March 6, 1989 and proposed training to be conducted September 19, 1989 and November 1989. Also, reviewed fire protection organization which states that the on-site fire brigade is primarily intended to be self sufficient, and the emergency operations coordinator shall have the authority to utilize offsite fire department The offsite fire departments that may be used are Keowee-Ebenezer Fire Department, Cornith Shiloh and Six Mile Fire Department. These fire departments are trained yearly in periodic drills and basic radiation principle. Action on Previous Inspection Findings (92701 and 92702)
(Closed) Unresolved Item 269, 270, 287/87-02-02, Determine the Acceptability of the SSF Dedicated Pum The licensee identified the above deficiency in a licensee event report (LER) dated October 15, 1986 and as discussed in detail under their Station Modification Design. Summary
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NSM-52634 of December 5, 198 The available water supply was not.
adequate to enable the SSF to accomplish its design function to maintain hot shutdown as long as 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> during the Appendix R scenario. In order to resolve this issue, the licensee has provided a portable submersible pumping system with sufficient makeup capability for the SSF water supply to ensure SSF hot shutdown decay heat removal function for a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> period. This portable pumping system is stored inside a vital area when not in use, and will be electrically as well as mechanically assembled and installed at the intake structure as an immediate action upon activation of the SS Since its operation is not required for a least three hours following a postulated fire event which necessitates SSF activation, we find that the portable submersible pumping system is an acceptable means of ensuring a sufficient water supply of the SS The staff notes that the proposed approach at Oconee departs from practices which have previously been found acceptable at other plant However, the staff believes the approach used at Oconee is unique and is supported by plant procedures and operator training which allows installation in sufficient time to support SSF operations, and is therefore acceptabl (Closed)
Unresolved Item 269, 270, 287/87-02-03, Adequacy of Spurious Activation Following Control Room Evacuation By letter dated April 20, 1988, the licensee stated that the NRC approved the design basis for Oconee SSF as documented by the NRC Safety Evaluation Report (SER) dated April 28, 1983. A design feature for the SSF included the assumption that no spurious valve operations will occur in the first ten minutes following a fir The staff's SER refers to the licensee's submittal dated September 20, 198 The above letter included a discussion of the design concept for SSF operation which assumed a 10 minute capability to transfer control to the SSF with no hot shorts or spurious actuation due to a fire postulated within the first 10 minutes of the even The staff's SER, however, did not specifically identify acceptance of the above but did concluded that the SSF met the*
requirements of Sections III.G.3 and III.L of Appendix R to 10 CFR 5 The staff has reconsidered the above deviation to the normally postulated assumption on use of the Appendix R alternate shutdown capability. It has been our position in the past that when the alternate shutdown system is to be utilized, loss of automatic functions and the concurrent most limiting single spurious action are assumed to occur. However, due to the uniquenesses of the SSF design for Oconee Nuclear Station and the
licensee's commitment for prompt manning and transfer of vital control and monitoring functions to the SSF, the staff concludes that the previous tacit acceptance of a 10 minute delay in postulation of spurious signals is still vali Concerning secondary side depressurization, we assume the licensee has verified that the main steam line boundary valves will not open due to spurious actuation signals resulting from the postulated fire after the first ten minutes or has identified designated manual actions or modifications outside the control room complex to ensure that the above valves will remain close Dukes response to this item was that the issue of spurious actuations leading to a lack of secondary side pressure control during operation of the SSF is beyond the original design basis of the system, which did not ensure against spurious failure As a result of internal reviews of Appendix R capabilities, Duke Power Company identified this concern as a potential shortcoming in the Oconee fire protection plan. In following up on this item a comprehensive evaluation of each potential steam leak path was performed as follows:
A. Category 1 In these cases the system design precludes excessive steam flow during catastrophic fir This is clearly acceptable per Appendix R Section II B. Category It is readily apparent that a steam leak will not lead to overcooling unless the leak flow rate exceeds the amount of steam which is produced in a steam generator by decay hea Therefore small leaks (less that 1.9" diameter equivalent size) are acceptabl C. Category 3 In these cases potential steam flow paths will be isolated by two valves such that excessive steam flow will require at least two independent spurious actuations of signal This approach is acceptable per the staff interpretation provided in Generic Letter 86-10 (Reference 3) which states
"The safe shutdown capability should not be adversely affected by any one spurious actuation or signal resulting from a fire in any plant area."
Two means of isolation will be provided, so that any one spurious actuation of valve will not lead to an open steam flow pat I
Isolation will be accomplished by operator action in the control room as a part of the procedure to proceed to the SSF. The valve controls which must be operated are located on the control board and are easily accessibl In previous correspondence with the NRC (Reference 4), Duke stated
"The originally accepted design concept for SSF operation was based on a 10 minute capability to transfer control to the SS Hot shorts of spurious actuation due to fire within the first 10 minutes of the event are not part of the design basi This justification is based on the extreme unlikehood of multiple spurious operations.... essentially coincident with loss of multiple mitigating systems' within a 10 minute perio Fires cannot instantaneously incapacitate all equipment in a large area and can only propagate in some real finite time within physical limits."
Therefore it is reasonable to expect that the valves would be operable from the control room due to the diverse electrical power sources at Oconee and the time which would be required for a real fire to propagate throughout the plan D. Category 4 The Category 4 penetrations (auxiliary steamand steam seals) have only a single isolation function provided. Based on the discussion of Category 3 penetrations, it is expected that this isolation will prevent excessive steam flo However, in the unlikely event that isolation is not accomplished, the SSF will still be capable of performing its design function of maintaining the plant at hot shutdow SSF procedures address the identification of a steam generator with excessive steam flow and call for throttling feedwater to the generator to prevent overcooling. If necessary, a unit will be maintained at hot shutdown utilizing only one steam generator for long term decay heat remova This, like Category 3, is acceptable per Generic Letter 86-10, since the safe shutdown capability will not be adversely affected by any one spurious actuatio Based on the engineering analyses and interpretations of NRC Guideline contained in Generic Letter 86-10, the Oconee approach to achieving and maintaining hot Shutdown following a design basis fire was found to be acceptabl (Closed)
Unresolved Item 269, 270, 287/87-02-04, NRR Resolution to Appendix R Exemptions, paragraphs 5.a.2 and Duke by letter dated November 11, 1982 requested an exemption from the Appendix R Section II G.2 separation requirements for redundant shutdown equipment components and cabling located within the reactor building These exemptions are listed below:
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Separation of SSF cables from other electrical cables within the Cask Decon Rooms,
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Separation of shutdown cables inside reactor building,
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Fire barrier separation between east and west penetration rooms,
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Cork insulation in the seismic gap of fire barrier Response to these issues are being addressed by NRR. Discussions with Len Wiens (NRR)
on August 21, 1989 indicated that Steve Varga was sending a letter to Duke Power Company to respond to these issues.. This item is closed and will be addressed by NR (Closed) Unresolved Item 269, 270, 287/87-02-06, Inadequate Fire Detection to meet requirements of Appendix R. II. G. 3 Section III. of Appendix R to 10 CFR 50 stipulates that where an alternate or dedicated shutdown capability has been provided for an area, room or zone, that location should also be provided with fire detection and a fixed fire suppression system. The following areas in the Auxiliary Building are not provided with fire detection and fire suppression systems:
Storage Areas -
Elevation 844 feet Battery and Cable Rooms -
Elevation 809 feet Equipment Room, Lab Area -
Elevation 796 feet Cask Decon Room Corridor Storage Areas - Elevations 783 and 775 feet The fire hazards in these areas were not considered significant enough to warrant the installation of fixed fire suppression system However, a fire could occur and burn undetected for a significant length of time, potentially affecting adjoining areas and safety systems. Fire detectors located in these areas would provide early notification to the operating crew of the occurrence of a fir Therefore, you are requested to provided a commitment to install additional fire detectors in these locations per the criteria in National Fire Protection Association Standards 72D and 72 This commitment and a schedule for implementation are requested within 60 days of the date of this letter. These items will be addressed by NR (Closed)
Inspector Followup Item 50-287/87-02-07, Sprinkler Protection Required for Instrument Calibration Room in-Area 30 This item was opened to ensure that the sprinkler system protecting the calibration room which is presently only provided above the suspended ceiling is modified to protect the hazards below the ceilin The inspector found that subsequent to the 87-02 inspection the licensee decided to modify the instrument calibration room. This modification is being done under Nuclear Modification (NSM) 52688. The inspector reviewed the NSM package and found that the licensee proposes to install one side wall type sprinkler head in the Instrument Calibration Roo The inspector looked at ongoing work which indicated this item is being done properly. Tentative completion date is October 198 (Closed) Violation 269, 270, 287/89-04-01, Failure to Implement Cutting and Welding Requirements Directive 4.25 for Cutting and Weldin The inspector reviewed the fire watch training scheduled on this item and verified that proper corrective actions were take.
Proposed Technical Specification 3.18 and 4.20 for Standby Shutdown Facility Oconee Nuclear Statio The standby shutdown facility is designed to provide an alternate and independent means to achieve and maintain hot shutdown conditions for one or more of the three Oconee Units thus mitigating the consequences of postualated fire, flood, or industrial sabotage incident By letters dated August 14, 1987 and August 12, 1988, Duke Power Company submitted to the NRC a revised proposed Technical Specification describing operability and surveillance requirements for the SS Duke is currently waiting for a response from NRR on this issu. Exit Interview The inspection scope and results were summarized on August 22, 1989, with those persons indicated in paragraph 1. The inspector described the areas inspected and discussed in detail the inspection result The licensee did not identify as proprietary any of the material provided or reviewed by the inspector during this-inspection.