ML20012B794
| ML20012B794 | |
| Person / Time | |
|---|---|
| Site: | Catawba  |
| Issue date: | 03/06/1990 |
| From: | Tucker H DUKE POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9003160287 | |
| Download: ML20012B794 (5) | |
Text
{{#Wiki_filter:~ V{- ( l 'Dake her Company llu o Tan PO Bat 33198 Lice hesident Charlotte, N C 2C42 - Nuclearhduchon c (7041373 4 531 ' DUKE POWER March 6, 1990 ~ U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D. C. 20555
Subject:
Catawba Nuclear Station, Units 1 and 2 Docket Nos. 50-413 and 50-414 NRC Inspection Report Nos. 50-413 & 50-414/89-29 Reply to a Notice of Violation Gentlement 4 My Ictter dated December 22, 1989 in response to Notice of Violation 89-29 explained in-depth the difference between the Annulus Ventilation (VE) System's, safety limit and its design limit. I also attempted to explain that, contrary to what was stated in the Notice of Violation, the VE system was at all times capable of performing its required safety _ function. In light of this, I requested that the violation be reconsidered or that additional details as to the exact nature of the violation be provided. Mr. Alan R. lierdt's letter dated February 6, 1990 responded to my request 'and concluded-that there were no grounds for withdrawing or changing the _ violation. I have decided to admit the violation in order to close this issue out, accordingly, my reply to the violation is attached. I continue' to take exception, however, to the position taken by the NRC in this matter that the " required safety function" of the VE system is the same as the " design limit." Very truly yours, a.rz k 4 -.--- -Ital B. Tucker RGM/03059002 Attachment I
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V\\?' a.: o s Page 1 of 3 / DUKE POWER COMPANY REPLY 10 A NOTICE OF VIOLATION 413/89-29-04 RESTATEMENT OF VIOLATION 10CFR50 Appendix B, Criterion III Design Control, requires in part that measures be established to assure that applicable regulatory requirements and the design basis for structures, systems, and components are correctly translated into specifications, drawings, procedures, and instructions. It is further required that these measures provide for verifying the adequacy of design, such as by the performance of design reviews, by the use of calculational methods, or the use of a testing program. Contrary to the above, design control measures were inadequate to ensure that the Annulus Ventilation System could perform its required safety function. In September 1989, it was found that the Annulus Ventilation System on both units had been inoperable since initial licensing. It was found that the Annulus Ventilation Systems were unable to produce and maintain a negative pressure of +0.5 inches water gauge throughout the annulus under all possibic outside air temperatures following a loss of coolant accident.
RESPONSE
1. Admission or Denial of Violation Duke Power Company admits that design control measures were inadequate to ensure that the Annulus Ventilation System could perform its design function as described in the FSAR; although, such measures were sufficient to ensure that the system could fulfill its design basis, i.e., required safety function. 2. Reason for the Violation if Admitted The operating setpoint specified by Design Engineering did not explicitly consider the effect of external temperatures on annulus (i.e., secondary containment) pressure. Information Notice 88-76 clearly indicates that this was not an unique situation. The operating setpoint did, as a matter of common practice, contain a degree of engineering margin to provide added assurance that the system would perform its required safety function. The operating setpoint and associated testing were insufficient to ensure that the system would perform its design function in the manner described in the FSAR. As stated previously, however, design control measures were sufficient to l ensure that the system performed its safety function. A detailed discussion is provided in Attachment II of H. B. Tucker's December 22, 1989 letter regarding this violation. I
q s-r 3 L j page 2 of 3 t' 3. Corrective Actions Taken and results Achieved a. A conference call with Region.II personnel on September 11, 1989 3 produced NRC concurrence that the Annulus Ventilation (VE) J l Systems' conditionally operable status was adequate while a permanent resolution was under development. On September 12, 1989 a reduction in the VE operating setpoint was selected as the j permanent resolution. The VE system operating setpoint was reduced to -1.5 inches water gauge on September 12, 1989. This ensured that the design limit of -0.5 inches water gauge would be l-satisfied under all operating conditions. A conference call with l Region II and NRR personnel on September 12 concluded that Catawba's course of action was satisfactory and that discretionary L enforcement was not required. Both trains of VE for both Units were successfully twsted at the new operating setpoints by i September 13, 1989. Test procedures have been revised to reflect j the new operating setpoint. b. All information notices have been reviewed to ensure that they have received an adequate evaluation. c. The Company's Operating Experience program (OEp) ensures that Duke power will be pro-active in evaluating emorging problems and in looking at similar problems across our system, d. performance tests have been established for VE that have acceptance criteria that are more limiting than Technical Specifications and provide a relationship between the Technical Specification surveillance and the Design Basis accident. 4. Corrective Steps Planned a. Design Engineering personnel will review'all safety related ventilation system differential pressure transmitters that indicate or control building pressurization (positive or negative) to ensure that reference point differences are accounted for, t b. Design Engineering personnel will develop a Design Basis document for the VE System. Following completion of this work, FSAR and Technical Specification revisions will be made as appropriate.
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,Q.4-lt i g 103 o.. - .i Page 3 of 3 8- ?. 5. 'Date When Full Compliance Will be Achieved r The Annulus Vent lation System has always been able to perform its safety.related function with regards to maintaining a negative secondary containment pressure. As a result:of the reduction in setpoint on September 12, 1989,. the system now meets the FSAR described ~ operating requirements; therefore. the station is presently ti: in full. compliance. L Completion of the " Corrective Steps Planned" for the VE System is scheduled for August 31, 1991. This date' allows time to complete the Design Basis Document for the VE System, and prepare necessary. license document revisions. The actual implementation date for the p[ TS change is unknown:since it depends upon NRC processing and i[ approval ~. 7 j:. I g I? c l}}