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| {{#Wiki_filter:}} | | {{#Wiki_filter:e e VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRO INIA 2 3 2 61 W. L. STEWART VICE PRESIDENT NUCLEAR OPERATIONS Mr. Harold R. Denton, Director June 27, 1986 Office of Nuclear Reactor Regulation ATTN: Mr. Lester S. Rubenstein, Director PWR Project Directorate |
| | #2 Division of PWR Licensing-A U.S. Nuclear Regulatory Commission Washington, DC 20555 Gentlemen: |
| | VIRGINIA ELECTRIC AND POWER COMPANY SURRY UNITS 1 AND 2 NORTH ANNA UNITS 1 AND 2 SUPPLEMENTAL RESPONSE TO GENERIC LETTER 83-28 ITEMS 4.2.1 AND 4.2.2 Serial NO. 86-334 NO/JWO/jmj:lDJB-001 Docket Nos: 50-280 50-281 50-338 50-339 License Nos: DPR-32 DPR-37 NPF-4 NPF-7 This letter discusses our proposed improvements to the Reactor Trip Breaker (RTB) Maintenance Programs at our North Anna and Surry Power Stations. |
| | The proposed Maintenance and Testing Program revisions were presented to the NRC staff during our April 7, 1986 meeting in Bethesda, Maryland. |
| | The two revisions to the Program consist of: 1. Reducing the number of repetitive RTB tripping in our maintenance procedures from 38 to 27 cycles and, 2. Extending the frequency of Testing Program from six exceeding 200 breaker activities. |
| | the performance of the RTB Maintenance and months to every twelve months, without cycles between inspection/maintenance In addition, each Westinghouse DB-50 RTB on our Surry and North Anna units will be thoroughly inspected and completely refurbished by Westinghouse at least once per 18 months (with extensions as defined in Technical Specifications) for at least three consecutive intervals. |
| | The refurbishment program will include tolerance checks on operating parts and returning breakers to "as built" or new condition, and testing the RTBs to new breaker specifications. |
| | The first such refurbishment has already been accomplished for our North Anna Units 1 and 2 and is in progress for Surry Unit 1. |
| | e 2 The following paragraphs provide the bases and justification for reducing the number of RTB tripping cycles during maintenance as well as the maintenance frequency. |
| | A. Each of the twenty elements described in the Westinghouse Owners Group (WOG) "Maintenance Program for DB-50 Reactor Trip Switchgear", dated October 14, 1983, with WOG-83-296 cover letter, dated December 15, 1983 will remain in the RTB maintenance program and procedures. |
| | The WOG document specifically states that, "The semi-annual activities (frequencies) might be extended to 9-12 months if (operating) experience shows this to be sufficient, provided that 200 breaker cycles are not exceeded during this interval". |
| | The twenty elements were also addressed in our responses to NRC Generic Letter 83-28, items 4.2.1 and 4.2.2, and in the NRC Safety Evaluations, dated April 24, 1985 for North Anna and May 3, 1985 for Surry, regarding these responses. |
| | The 20 elements remain intact in the RTB maintenance program; only the frequency of the interval or the RTB cycling is decreased. |
| | B. A change to the RTB maintenance program concerning breaker cycling or testing frequency does not involve a change to any present or proposed Technical Specification for Surry or North Anna. C. The company has documented and trended the RTB performance data for over two years and has verified that the operating experience and data has not indicated any adverse trends in RTB performance. |
| | The trending and monitoring of these parameters will continue. |
| | D. Frequently, the semi-annual RTB maintenance must be performed during full power operations, which increases the probability of a reactor trip and the probability of challenges to safety systems. Increasing the time between the maintenance intervals will reduce the opportunity for occurrence of these events without reducing the adequacy of the RTB maintenance program. E. The periodic surveillance testing of the RTBs will continue on a monthly basis at Surry and bimonthly at North Anna (staggered testing). |
| | This testing cycles each RTB, measures the breaker response time (Surry only), and independently verifies operability of the undervoltage trip attachment (UVTA) and the shunt trip at both sites. The system response time is measured during refueling outages at North Anna in accordance with Technical Specification requirements. |
| | F. Our experience indicates that excessive cycling of the RTB reduces the effectiveness of lubrication and increases the wear on RTB components. |
| | For example, the alcohol-based molybdenum disulfide UVTA lubricant tends to fall off the UVTA during the energetic opening of the breaker, following evaporation of the alcohol. The finely ground molybdenum disulfide ore can be observed collecting as dust in the breaker, beneath the UVTA and is a primary reason for the implementation of the monitoring and lubricating program every 200 cycles. We have also observed wear on the auxiliary contacts and its latching arm following the repetitive racking in and out operations required by the maintenance and testing programs. |
| | In addition, the energetic and repetitive cycling of the RTB's is hypothesized as the cause, for losing one of the seven spring clip type lock rings from the grooved ends of the UVTA pivot and latch pins. Two of the three UVTA "failures" that occurred during testing at our Surry .I 3 facility after 1981 were due to the loss of a small lock ring which permitted latch or pivot pin displacement and binding of the UVTA. (The third failure was apparently due to an improperly machined UVTA latch pin). Our maintenance procedures require a visual inspection of the lock rings to ensure they are in place and secure. Preoperational inspections and testing of new UVTA's is also performed to ensure operability. |
| | G. Element 17 in the WOG program, "Westinghouse Maintenance Program for DB-50 Reactor Trip Switchgear", identifies the functional RTB check prior to returning the breaker to service. This check closes and trips the breaker electrically and manually to demonstrate that breaker functions including closing, shunt tripping and undervoltage tripping (10 UV trips) are normal. We can determine no firm basis for the 10 undervoltage trips, other than the fact that newly manufactured DB-50 breakers are tripped 10 times by Westinghouse to verify proper operation of the new breaker. After reviewing the comprehensive inspections and testing which we frequently perform on the DB-50 RTBs, we have determined that 10 RTB cycles is excessive. |
| | Subsequent to cycling the RTB 25 times during our periodic Maintenance and Testing Program, we will cycle the RTB two more times to complete the functional check of the RTB prior to returning it to service. Our procedures will, of course, ensure that the breaker or components will be cycled several times whenever cleaning and lubrication are performed (page 39 of WOG Procedure). |
| | H. Handling of the RTBs is excessive. |
| | Every 6 months, the RTBs must be racked out and removed from their respective cubicles to perform maintenance and testing. The likelihood of electrical or mechanical damage to the breaker and its components increases with the frequency of handling. |
| | Similarly, the chance for human error increases when the equipment maintenance and testing increases. |
| | In fact, while the design, maintenance, and testing of the RTBs have been improving (e.g. Auto shunt trip, lubrication techniques, response times, etc.) to increase the reliability of the RTB, the probability for human error or accidental component damage has actually increased due to the frequency of the work and the man-hours involved. |
| | We hope to reduce the risk of human error by reducing the frequency of the RTB maintenance. |
| | Implementation and monitoring of this program will increase the reliability of the Reactor Trip Breakers. |
| | I. As indicated in WCAP-10852, "Report of the DB-50 Reactor Trip Breaker Shunt and UVTA Life Cycle Tests", the shunt trip attachment appears to be a simple and reliable tripping device for the DB-50 RTB. The automatically actuated shunt trip feature has been installed at Surry and North Anna and is routinely tested to verify operability. |
| | The shunt trip attachment on each RTB is also inspected to ensure that the trip lever to trip bar clearance is between 0.031 and 0.125 inches. With the addition of the automatic actuation of the shunt trip attachment, diverse features exist to effect a reactor trip for each RTB. Initially, we were hoping to reduce the number of RTB cycles per year by over 50%; however, after reviewing WCAP-11092 (October 29, 1985 RTB failure at D.C. Cook) and discussing it with members of your staff, we have decided to perform limited testing of our RTBs prior to shipment to Westinghouse for refurbishment. |
| | The RTBs will be tested again when they are returned to the 4 site to measure and record RTB performance data and verify operability. |
| | This data is also important to ensure that any problems which may occur during shipping or handling are promptly identified and corrected. |
| | We are currently working with Westinghouse on the design and fabrication of a molded and cushioned, form-fitting RTB container which would be environmentally sealed during shipment. |
| | The test data would therefore monitor performance of the container and transportation procedures. |
| | The RTB containers could also be used on site to store spare RTBs, as required. |
| | However, the extension of the RTB Maintenance and Testing Program to 12 month intervals should in itself improve the reliability of the Reactor Trip Breakers. |
| | Perhaps the most significant point of our proposed RTB refurbishment and Maintenance and Testing Programs is that the communications and exchange of information between Westinghouse and the Company will be enhanced. |
| | For example, our engineers have observed RTB testing at the Westinghouse facilities and Westinghouse Senior Breaker Engineers have participated in RTB Committee meetings in Virginia. |
| | This team effort by vendor and user will help to ensure reliable Reactor Trip Breaker operation. |
| | We plan to implement our proposed revisions to the RTB Maintenance and Testing Programs within the next 90 days at our Surry and North Anna facilities. |
| | If you require additional information or have any questions, please contact us. Very truly yours, ti~% W. L. Stewart Attachments cc: Dr. J. Nelson Grace Regional Administrator Region II NRC Senior Resident Inspector North Anna Power Station NRC Senior Resident Inspector Surry Power Station Mr. L.B. Engle NRC North Anna Project Manager PWR Project Directorate |
| | #2 Division of PWR Licensing-A Mr. C. Patel NRC Surry Project Manager PWR Project Directorate |
| | #2 Division of PWR Licensing-A}} |
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Category:CORRESPONDENCE-LETTERS
MONTHYEARML18152B3571999-10-22022 October 1999 Requests Relief from Temporary Repair of Through Wall Leak Discovered on 30 Inch Component Cooling Heat Exchanger Discharge Pipe Associated with Service Water Sys Common to Surry Units 1 & 2 ML20217K4391999-10-18018 October 1999 Provides Response to RAI to Support USI A-46 Program Submittal for North Anna Power Station,Units 1 & 2.Rev 10 to BNL Rept 52361,encl ML20217H3301999-10-14014 October 1999 Forwards Rev 0 to COLR for North Anna 2 Cycle 14 Pattern Su. No New Commitments Intended by Ltr ML18152B3581999-10-14014 October 1999 Submits Response to Violations Noted in Insp Repts 50-280/98-201 & 50-281/98-201.Corrective Actions:Visual Insps Were Completed on Accessible Coatings Inside Containment for Both Units 1 & 2 ML18152B3541999-10-12012 October 1999 Requests Use of Code Case N-532 & N-619,per Provisions of 10CFR50.55a(a)(3).Detailed Info Supporting Request,Encl. Attachment 2 Includes Technical White Paper That Provides Further Technical Info ML20216K1681999-10-0101 October 1999 Forwards Vols I-VIII of Rev 35 to UFSAR for Naps.Rev Also Includes Update to Chapter 17 of Ufsar,Which Contains Operational QA Program.Changes to Program Description Do Not Reduce Commitments Contained Therein ML20212J9101999-10-0101 October 1999 Forwards SE Accepting Licensee 990916 & 27 Relief Requests IWE-3 for Plant.Se Addresses Only IWE-3 Due to Util Urgent Need for Relief.Requests IWE-7 & IWE-8 Will Be Addressed at Later Date ML18152B3401999-09-27027 September 1999 Requests That Ma Walker Be Removed from List of Individuals Scheduled to Take Exam IAW Guidance Provided in NUREG-1021, Operator Licensing Exam Stds for Power Reactors ML18152B3391999-09-27027 September 1999 Forwards Revised Relief Request IWE-3,which Now Includes Addl Visual Exam Requirement After post-repair or Mod Pressure Testing Is Completed,Per Telcon with NRC ML20212G5091999-09-22022 September 1999 Forwards in Triplicate,Applications for Renewal of Licenses for Listed Individuals.Encls Withheld,Per 10CFR2.790(a)(6) ML18152B3381999-09-21021 September 1999 Forwards in Triplicate,Applications for Renewal of License for Bf Jurewicz & JW Heide.Without Encls ML18152B3331999-09-17017 September 1999 Forwards Revised 180-day Response to NRC GL 96-05, Periodic Verification of Design-Basis Capability of Safety-Related Motor-Operated Valves. ML18152B6671999-09-17017 September 1999 Forwards Two NRC Forms 536,containing Info on Proposed Site Specific Operator Licensing Exam Schedules & Estimated Number of Applicants Planning to Take Exams And/Or Gfes,In Response to NRC Administrative Ltr 99-03 ML18152B3341999-09-16016 September 1999 Requests Relief from Specific Requirements of Subsection IWE of 1992 Edition with 1992 Addenda of ASME Section XI Re Containment Liner Examination Requirements,For North Anna & Surry Power Stations ML18152B4521999-09-14014 September 1999 Forwards Comments on Review of Preliminary Accident Sequence Precursor Analysis of Operational Event That Occurred at Plant,On 980508,as Reported in LER 98-009 ML20216F1381999-09-0808 September 1999 Forwards Retake Exam Repts 50-280/99-302 & 50-281/99-302 on 990824.One SRO Applicant Who Received re-take Operating Test Passed re-take Exam ML18152B4501999-09-0808 September 1999 Submits in Triplicate,Application for Renewal of License for Rd Scherer,Iaw 10CFR55.57.Requests That Certification of Medical Exam by Facility Licensee,Nrc Form 396,be Withheld from Public Disclosure,Per 10CFR2.790(a)(6) ML20211N2531999-09-0808 September 1999 Responds to Request to Exceed 60,000 Mwd/Mtu Lead Rod Burnup in Small Number of Fuel Rods in North Anna Unit 2.Informs That NRC Offers No Objection to Requested Use of Rods in Reconstituted Fuel Assembly.Se Supporting Request Encl ML20211L9151999-09-0101 September 1999 Forwards Response to NRC Request for Comments Re Closure of Review of Response to GL 92-01,Rev 1,Suppl 1, Reactor Vessel Structural Integrity ML18152B4471999-09-0101 September 1999 Requests That NRC Remove Listed Labels from Distribution ML20211J2211999-08-31031 August 1999 Approves Request to Remove Augmented ISI (Aii) Program for RCS Bypass Lines from North Anna Licensing Basis.Se Re Request to Apply LBB to Eliminate Augmented Insp Program on RCS Bypass Lines Encl ML20211H4131999-08-27027 August 1999 Informs That Util Revised Encl Bases for TS 2.2.1, Reactor Trip Sys Instrumentation Setpoints, Discussing Steam Flow/ Feed Flow Mismatch Portion of Steam Flow/Feed Flow Mismatch & Low SG Water Level Reactor Trip Setpoint ML18152B3711999-08-27027 August 1999 Forwards LER 99-005-00,per Plant TS Table 3.7.6.Rept Has Been Reviewed by Station Nuclear Safety & Operating Committee.Commitment Made by Util,Listed ML18152B3851999-08-23023 August 1999 Forwards Revised TS Basis Pages for TS 3.1.B,deleting Reactor Vessel Toughness Data Duplicated in Ufsar.Ref to Applicable UFSAR Section Included in TS Basis ML20138B3241999-08-23023 August 1999 Forwards Draft Response to Question 1 Re NAPS USI A-46 ML20211D9041999-08-20020 August 1999 Forwards Revised Pages to Third Ten Year ISI Program & Relief Requests, Replacing Pages in 990408 Submittal ML18152B3681999-08-20020 August 1999 Submits 30-day Rept Re Two Instances in Which Conditions of Approval in Coc Were Not Observed in Making Shipment.Two Type B Shipments Using Model CNS 8-120B Package Were Made After Expiration of QA Program Approval Between 990531-0628 ML18152B3661999-08-20020 August 1999 Provides Medical Status Rept for E Washington,As Required by License Conditions.Summary of E Washington Current Physical Exam & Pertinent Lab Data Attached.Encl Withheld,Per 10CFR2.790(a)(6) ML18152B3651999-08-20020 August 1999 Requests Removal of License Condition from Sh Wightman Operator License SOP-21538.Updated NRC Form 396 Is Encl.Form NRC 396 Withheld,Per 10CFR2.790(a)(6) ML18152B3801999-08-18018 August 1999 Forwards Technical Rept NE-1206,Rev 0, Surry Unit 2,Cycle 16 Startup Physics Tests Rept, Summarizing Results of Physics Testing Program Performed After Initial Criticality on 990525 ML20211B3871999-08-17017 August 1999 Requests Permission to Routinely Discharge from SW Reservior to Waste Heat Treatment Facility Under Existing Vpdes Permit Through Outfalls 108 & 103.Discharges Are Scheduled to Commence on 990907,due to High Priority Placed on Project ML20210T0671999-08-13013 August 1999 Informs of Completion of Review of Proposed Revs of Schedule for Withdrawal of Rv Surveillance Capsules Submitted by VEPCO on 981217.Approves Proposed Revs.Forwards Safety Evaluation ML18152B3781999-08-13013 August 1999 Forwards ISI Summary Rept for Surry Power Station,Unit 2 for 1999 Refueling Outage.Rept Provides Summary of Examination Performed During Outage for Third ISI Interval.No New Commitments Were Made ML18152B3751999-08-13013 August 1999 Forwards LER 99-004-00,IAW 10CFR50.73.Commitment Made by Util,Listed ML20210Q9841999-08-12012 August 1999 Forwards Rev 1 to Vepc COLR for North Anna Unit 2,Cycle 13 Pattern Ud, Per TS 6.9.1.7.d.COLR Was Revised to Include Temp Coastdown Operation at End of Cycle 13 ML20210Q7661999-08-0606 August 1999 Requests Exception to 10CFR50.4 Requirement to Provide Total of Twelve Paper Copies When Submitting Surry & North Anna UFSAR Updates.Seek Approval to Submit Only Signed Original & One CD-ROM Version,Per Conversation with J Skoczlas ML18152B4081999-08-0606 August 1999 Forwards Response to NRC 990520 & 0525 RAIs Re North Anna & Surry Responses to GL 95-07, Pressure Locking & Thermal Binding of SR Power-Operated Gate Valves. ML18152B4091999-08-0505 August 1999 Forwards Vepc semi-annual fitness-for-duty Program Performance Data Rept for 990101-990630,IAW 10CFR26.71(d) ML20210N2921999-08-0505 August 1999 Discusses Which Submitted Proposed TSs Bases Change for Containment Leakage. Licensee Changes to Bases May Be Subj to Future Insps or Audits ML20210J8861999-08-0202 August 1999 Provides Clarification to Commitment Made in Identifying Extent by Which Existing Plant Design Complied with RG 1.97,specifically Re Variable, Radiation Exposure Rate ML18152B4001999-07-29029 July 1999 Requests Relief from Certain Impractical Requirements of ASME Section XI Code Associated with Partial Exams Conducted During 1998 Surry Unit 1 Refueling Outage.Relief Request SR-020 Encl ML18152B3981999-07-28028 July 1999 Forwards 60-day Response to GL 99-02, Lab Testing of Nuclear-Grade Activated Charcoal. Commitments Contained in Ltr,Listed ML20210F6121999-07-28028 July 1999 Forwards Supplemental Info on Proposed Irradiation of Fuel Rods Beyond Current Lead Rod Burnup Limit,Documenting Info Provided During 990624 Meeting & Suppl Original Submittal ML18152B3971999-07-26026 July 1999 Provides Estimates of Licensing Actions Expected to Be Submitted in Fys 2000 & 2001,in Response to NRC AL 99-02 ML18152B3961999-07-23023 July 1999 Forwards Preliminary,Uncertified License Application & Medical Certification for License to Operate Surry Power Station Units 1 & 2 for Ds Cobb.Encl Withheld,Per 10CFR2.790 (a)(6) ML18152B3991999-07-23023 July 1999 Requests That License for Jz Laplante Be Canceled as License Is No Longer Required ML18151A6281999-07-23023 July 1999 Forwards Revised Epips,Including Rev 19 to EPIP-4.02,rev 14 to EPIP-4.16,rev 8 to EPIP-4.21 & Rev 7 to EPIP-4.30.EP & EPIPs Continue to Meet Stds of 10CFR50.47(b) ML18152B3931999-07-16016 July 1999 Forwards Updated NRC Form 396 & Ltr,Which Documents Medical Status of Mb Gross,License SOP-20476-2.Encl Withheld from Public Disclosure,Per 10CFR2.790(a)(6) ML20209E7621999-07-0909 July 1999 Provides Addl Info to Justify Use of Less than One Gpm Detectable Leakage Rate to Establish Required Margin for Crack Stability in LBB Analysis,Per 980623 Application on Reactor Coolant Loop Bypass Lines 05000338/LER-1999-005, Forwards LER 99-005-00,IAW 10CFR50.73.Commitment Made by Util Encl1999-07-0808 July 1999 Forwards LER 99-005-00,IAW 10CFR50.73.Commitment Made by Util Encl 1999-09-08
[Table view] Category:INCOMING CORRESPONDENCE
MONTHYEARML18152B3571999-10-22022 October 1999 Requests Relief from Temporary Repair of Through Wall Leak Discovered on 30 Inch Component Cooling Heat Exchanger Discharge Pipe Associated with Service Water Sys Common to Surry Units 1 & 2 ML20217K4391999-10-18018 October 1999 Provides Response to RAI to Support USI A-46 Program Submittal for North Anna Power Station,Units 1 & 2.Rev 10 to BNL Rept 52361,encl ML20217H3301999-10-14014 October 1999 Forwards Rev 0 to COLR for North Anna 2 Cycle 14 Pattern Su. No New Commitments Intended by Ltr ML18152B3581999-10-14014 October 1999 Submits Response to Violations Noted in Insp Repts 50-280/98-201 & 50-281/98-201.Corrective Actions:Visual Insps Were Completed on Accessible Coatings Inside Containment for Both Units 1 & 2 ML18152B3541999-10-12012 October 1999 Requests Use of Code Case N-532 & N-619,per Provisions of 10CFR50.55a(a)(3).Detailed Info Supporting Request,Encl. Attachment 2 Includes Technical White Paper That Provides Further Technical Info ML20216K1681999-10-0101 October 1999 Forwards Vols I-VIII of Rev 35 to UFSAR for Naps.Rev Also Includes Update to Chapter 17 of Ufsar,Which Contains Operational QA Program.Changes to Program Description Do Not Reduce Commitments Contained Therein ML18152B3401999-09-27027 September 1999 Requests That Ma Walker Be Removed from List of Individuals Scheduled to Take Exam IAW Guidance Provided in NUREG-1021, Operator Licensing Exam Stds for Power Reactors ML18152B3391999-09-27027 September 1999 Forwards Revised Relief Request IWE-3,which Now Includes Addl Visual Exam Requirement After post-repair or Mod Pressure Testing Is Completed,Per Telcon with NRC ML20212G5091999-09-22022 September 1999 Forwards in Triplicate,Applications for Renewal of Licenses for Listed Individuals.Encls Withheld,Per 10CFR2.790(a)(6) ML18152B3381999-09-21021 September 1999 Forwards in Triplicate,Applications for Renewal of License for Bf Jurewicz & JW Heide.Without Encls ML18152B6671999-09-17017 September 1999 Forwards Two NRC Forms 536,containing Info on Proposed Site Specific Operator Licensing Exam Schedules & Estimated Number of Applicants Planning to Take Exams And/Or Gfes,In Response to NRC Administrative Ltr 99-03 ML18152B3331999-09-17017 September 1999 Forwards Revised 180-day Response to NRC GL 96-05, Periodic Verification of Design-Basis Capability of Safety-Related Motor-Operated Valves. ML18152B3341999-09-16016 September 1999 Requests Relief from Specific Requirements of Subsection IWE of 1992 Edition with 1992 Addenda of ASME Section XI Re Containment Liner Examination Requirements,For North Anna & Surry Power Stations ML18152B4521999-09-14014 September 1999 Forwards Comments on Review of Preliminary Accident Sequence Precursor Analysis of Operational Event That Occurred at Plant,On 980508,as Reported in LER 98-009 ML18152B4501999-09-0808 September 1999 Submits in Triplicate,Application for Renewal of License for Rd Scherer,Iaw 10CFR55.57.Requests That Certification of Medical Exam by Facility Licensee,Nrc Form 396,be Withheld from Public Disclosure,Per 10CFR2.790(a)(6) ML18152B4471999-09-0101 September 1999 Requests That NRC Remove Listed Labels from Distribution ML20211L9151999-09-0101 September 1999 Forwards Response to NRC Request for Comments Re Closure of Review of Response to GL 92-01,Rev 1,Suppl 1, Reactor Vessel Structural Integrity ML20211H4131999-08-27027 August 1999 Informs That Util Revised Encl Bases for TS 2.2.1, Reactor Trip Sys Instrumentation Setpoints, Discussing Steam Flow/ Feed Flow Mismatch Portion of Steam Flow/Feed Flow Mismatch & Low SG Water Level Reactor Trip Setpoint ML18152B3711999-08-27027 August 1999 Forwards LER 99-005-00,per Plant TS Table 3.7.6.Rept Has Been Reviewed by Station Nuclear Safety & Operating Committee.Commitment Made by Util,Listed ML18152B3851999-08-23023 August 1999 Forwards Revised TS Basis Pages for TS 3.1.B,deleting Reactor Vessel Toughness Data Duplicated in Ufsar.Ref to Applicable UFSAR Section Included in TS Basis ML20138B3241999-08-23023 August 1999 Forwards Draft Response to Question 1 Re NAPS USI A-46 ML20211D9041999-08-20020 August 1999 Forwards Revised Pages to Third Ten Year ISI Program & Relief Requests, Replacing Pages in 990408 Submittal ML18152B3681999-08-20020 August 1999 Submits 30-day Rept Re Two Instances in Which Conditions of Approval in Coc Were Not Observed in Making Shipment.Two Type B Shipments Using Model CNS 8-120B Package Were Made After Expiration of QA Program Approval Between 990531-0628 ML18152B3661999-08-20020 August 1999 Provides Medical Status Rept for E Washington,As Required by License Conditions.Summary of E Washington Current Physical Exam & Pertinent Lab Data Attached.Encl Withheld,Per 10CFR2.790(a)(6) ML18152B3651999-08-20020 August 1999 Requests Removal of License Condition from Sh Wightman Operator License SOP-21538.Updated NRC Form 396 Is Encl.Form NRC 396 Withheld,Per 10CFR2.790(a)(6) ML18152B3801999-08-18018 August 1999 Forwards Technical Rept NE-1206,Rev 0, Surry Unit 2,Cycle 16 Startup Physics Tests Rept, Summarizing Results of Physics Testing Program Performed After Initial Criticality on 990525 ML18152B3781999-08-13013 August 1999 Forwards ISI Summary Rept for Surry Power Station,Unit 2 for 1999 Refueling Outage.Rept Provides Summary of Examination Performed During Outage for Third ISI Interval.No New Commitments Were Made ML18152B3751999-08-13013 August 1999 Forwards LER 99-004-00,IAW 10CFR50.73.Commitment Made by Util,Listed ML20210Q9841999-08-12012 August 1999 Forwards Rev 1 to Vepc COLR for North Anna Unit 2,Cycle 13 Pattern Ud, Per TS 6.9.1.7.d.COLR Was Revised to Include Temp Coastdown Operation at End of Cycle 13 ML20210Q7661999-08-0606 August 1999 Requests Exception to 10CFR50.4 Requirement to Provide Total of Twelve Paper Copies When Submitting Surry & North Anna UFSAR Updates.Seek Approval to Submit Only Signed Original & One CD-ROM Version,Per Conversation with J Skoczlas ML18152B4081999-08-0606 August 1999 Forwards Response to NRC 990520 & 0525 RAIs Re North Anna & Surry Responses to GL 95-07, Pressure Locking & Thermal Binding of SR Power-Operated Gate Valves. ML18152B4091999-08-0505 August 1999 Forwards Vepc semi-annual fitness-for-duty Program Performance Data Rept for 990101-990630,IAW 10CFR26.71(d) ML20210J8861999-08-0202 August 1999 Provides Clarification to Commitment Made in Identifying Extent by Which Existing Plant Design Complied with RG 1.97,specifically Re Variable, Radiation Exposure Rate ML18152B4001999-07-29029 July 1999 Requests Relief from Certain Impractical Requirements of ASME Section XI Code Associated with Partial Exams Conducted During 1998 Surry Unit 1 Refueling Outage.Relief Request SR-020 Encl ML18152B3981999-07-28028 July 1999 Forwards 60-day Response to GL 99-02, Lab Testing of Nuclear-Grade Activated Charcoal. Commitments Contained in Ltr,Listed ML20210F6121999-07-28028 July 1999 Forwards Supplemental Info on Proposed Irradiation of Fuel Rods Beyond Current Lead Rod Burnup Limit,Documenting Info Provided During 990624 Meeting & Suppl Original Submittal ML18152B3971999-07-26026 July 1999 Provides Estimates of Licensing Actions Expected to Be Submitted in Fys 2000 & 2001,in Response to NRC AL 99-02 ML18152B3991999-07-23023 July 1999 Requests That License for Jz Laplante Be Canceled as License Is No Longer Required ML18152B3961999-07-23023 July 1999 Forwards Preliminary,Uncertified License Application & Medical Certification for License to Operate Surry Power Station Units 1 & 2 for Ds Cobb.Encl Withheld,Per 10CFR2.790 (a)(6) ML18151A6281999-07-23023 July 1999 Forwards Revised Epips,Including Rev 19 to EPIP-4.02,rev 14 to EPIP-4.16,rev 8 to EPIP-4.21 & Rev 7 to EPIP-4.30.EP & EPIPs Continue to Meet Stds of 10CFR50.47(b) ML18152B3931999-07-16016 July 1999 Forwards Updated NRC Form 396 & Ltr,Which Documents Medical Status of Mb Gross,License SOP-20476-2.Encl Withheld from Public Disclosure,Per 10CFR2.790(a)(6) ML20209E7621999-07-0909 July 1999 Provides Addl Info to Justify Use of Less than One Gpm Detectable Leakage Rate to Establish Required Margin for Crack Stability in LBB Analysis,Per 980623 Application on Reactor Coolant Loop Bypass Lines 05000338/LER-1999-005, Forwards LER 99-005-00,IAW 10CFR50.73.Commitment Made by Util Encl1999-07-0808 July 1999 Forwards LER 99-005-00,IAW 10CFR50.73.Commitment Made by Util Encl ML18152B4401999-07-0101 July 1999 Informs NRC That on 990511,Dominion Resources,Inc,Executed Amended & Restated Agreement & Plan of Merger with Consolidated Natural Gas Co ML18152B4371999-06-24024 June 1999 Forwards Response to NRC Request for Clarification of Relief Requests Submitted on 990212,requesting Relief from Performing Hydrostatic Testing for Certain Small Diameter Class 1,RCS Pressure Boundary Connections ML18152B4361999-06-22022 June 1999 Forwards Response to RAI Re Surry & North Anna Power Stations,Units 1 & 2,per GL 96-06 ML20212J2951999-06-22022 June 1999 Forwards Corrected Markup & Typed Version of Affected Pages. Requests That Attached Pages for Those Previously Provided in 990506 Submittal Be Replaced & Incorporated Into NRC Review of Proposed TS ML20196F1151999-06-22022 June 1999 Forwards Relief Requests NDE-047 & NDE-048 for North Anna Power Station,Unit 1 Re ASME Section XI ISI Program ML20195J7011999-06-15015 June 1999 Forwards Revised EPIP 2.01 Which Corrects Typo That Was Found in Step 10 of Procedure.Rev Does Not Implement Actions That Decrease Effectiveness of EP ML18152B4301999-06-0303 June 1999 Informs of Util Intention to Revise Schedule for Submittal of License Renewal Applications for Surry & North Anna Power Stations to March 2002 1999-09-08
[Table view] Category:UTILITY TO NRC
MONTHYEARML18153C3661990-09-20020 September 1990 Forwards Topical Rept VEP-NE-3-A, Qualification of WRB-1 CHF Correlation in VEPCO Cobra Code. ML20065D5671990-09-20020 September 1990 Forwards Rev 15 to Security Personnel Training & Qualification Plan.Rev Withheld ML18153C3701990-09-18018 September 1990 Forwards Addl Info Re Facility Containment Isolation Valve Type C Test,Per 900914 10CFR50,App J Exemption Request ML18152A2341990-09-14014 September 1990 Requests Exemption from 10CFR50,App J Section III.D.3 Re Local Leak Rate Testing During Every Reactor Shutdown. Basis & Justification for Exemption Encl ML20059J3341990-09-13013 September 1990 Forwards Rev 15 to Nuclear Security Personnel Training & Qualification Plan.Rev Withheld ML20059H7391990-09-10010 September 1990 Forwards Rev 15 to ISFSI Nuclear Security Personnel Training & Qualification Plan.Rev Withheld ML20059H2931990-09-0707 September 1990 Advises of Review & Approval of ASME Section XI Inservice Insp Program Interval 1 Repair & Replacement Program Change to Applicable Code Edition & Addenda ML20064A5201990-09-0707 September 1990 Responds to NRC Re Violations Noted in Insp Repts 50-338/90-15 & 50-339/90-15.Corrective Actions:Procedures Revised to Include Tolerance Bands for Temp Control Switch Setpoints & Involved Personnel Counseled ML18151A2901990-08-31031 August 1990 Forwards Rev 10 to Updated FSAR for Surry Power Station Units 1 & 2,representing Second Updated FSAR Submitted This Yr ML20059E5481990-08-31031 August 1990 Forwards Supplemental Info Re Deletion of Pressurizer Safety Valve Requirement During Mode 5.Current Tech Spec Requiring One Operable Safety Valve in Mode 5 Unnecessary & May Be Deleted ML18153C3451990-08-29029 August 1990 Forwards Proprietary Semiannual Fitness for Duty Program Performance Data Rept for 900103-0630.Rept Includes Summaries of Mgt Sanctions Imposed,Actions Taken to Correct Program Weaknesses & Events Reported to Nrc.Encl Withheld ML18153C3381990-08-22022 August 1990 Responds to NRC 900723 Ltr Re Violations Noted in Insp Rept 50-280/90-21 & 50-281/90-21.Corrective actions:as-found-as- Left Conditions of Auxiliary Feedwater Evaluated & Found Operable ML18153C3391990-08-22022 August 1990 Requests Approval for Use of Plugs Fabricated of nickel- chromium-iron Uns N-06690 Matl (Alloy 690) to Plug Tubes in Steam Generators for Mechanical & Welded Applications ML20063Q1241990-08-15015 August 1990 Provides Supplemental Info for 900115 Tech Spec Change Request Re Max Allowable Control Rod Drop Time.Retained DNBR Margin Tracked & Documented by Calculational Note ML20058N5941990-08-0808 August 1990 Responds to NRC Re Violations Noted in Insp Repts 50-338/90-11 & 50-339/90-11.Corrective Actions:Procedure Revised to Limit Applicablity to Small Refueling Cavity Leaks & Listed Evaluations & Revs Will Be Made to EOP ML18153C3171990-08-0101 August 1990 Resubmits Synopsis of Changes to Updated Operational QA Program Topical Rept Vep 1-5A ML18153C3161990-08-0101 August 1990 Provides Supplemental Response to NRC 900629 Ltr Re Electrical Crossties,Load Shedding on Nonblackout Unit & Emergency Diesel Generator Reliability.Emergency Diesel Generator Reliability Program in Place,Per Reg Guide 1.155 ML18153C3091990-07-30030 July 1990 Provides Outline of Plan to Meet 10CFR50 App G Requirements, for Low Upper Shelf Energy Matls,Per NRC 900521 Request ML18153C3061990-07-30030 July 1990 Forwards Revised Tech Spec Pages,Addressing Constitution of Quorum & Timeliness of Mgt Safety Review Committe Meeting Minutes,Per NRC Request ML18153C3101990-07-26026 July 1990 Forwards Decommissioning Financial Assurance Certification Rept..., Nuclear Decommissioning Trust Agreement & Nonqualified Nuclear Decommissioning Trust Amended & Restated Trust Agreement, Per 10CFR50.75 ML18153C3051990-07-26026 July 1990 Advises That Util Submitted Decommissioning Funding Plan & Financial Assurance Info W/Isfsi License Application ML18153C3041990-07-26026 July 1990 Responds to NRC 900626 Ltr Re Violations Noted in Insp Rept 50-281/90-20.Corrective Actions:Leaking Drain Plug & Upper Drain Plug on Motor Replaced W/Oil Drain Assemblies Composed of Piping & Valves ML18153C3031990-07-26026 July 1990 Advises of Withdrawal of Request for NRC Review & Approval of Engineering Evaluation 8.Revised Evaluation Will Be Maintained Onsite for NRC Audit During Future Insps,Per Generic Ltr 86-10 ML20055H5651990-07-20020 July 1990 Requests for Temporary Waiver of Compliance from Requirement of Tech Spec 3.3.1.1,Table 2.3-2 Re Response Time Testing. Request Does Not Pose Significant Hazards Consideration ML18153C2901990-07-18018 July 1990 Responds to NRC Bulletin 90-001, Loss of Fill-Oil in Transmitters Mfg by Rosemount. Listed Transmitters Compiled.Transmitters Found Installed within Reactor Protection or ESFAS Have Been Replaced ML20055F9361990-07-16016 July 1990 Advises That No 30-day Rept Will Be Made Re Degradation of Seismic Support Bolts of post-accident Hydrogen Recombiners 1-HC-HC-1 & 2-HC-HC-1 ML20044B3501990-07-13013 July 1990 Forwards Monthly Operating Repts for June 1990 & Corrected May 1990 Rept Pages for North Anna Power Station ML18153C2861990-07-12012 July 1990 Requests Cancellation of Operator Licenses for Listed Individuals.Licenses No Longer Required ML18153C2871990-07-11011 July 1990 Responds to Violations Noted in Insp Repts 50-280/90-18 & 50-281/90-18.Corrective Actions:Permanent Drain Line Installed & Matrix Which Describes Proper Ventilation Alignment for Plant Conditions Provided for Personnel Use ML20055E8121990-07-0909 July 1990 Requests Cancellation of Licenses Listed ML18153C2851990-07-0606 July 1990 Forwards Response to Generic Ltr 90-04 Re Status of Generic Safety Issues ML18153C2831990-07-0303 July 1990 Advises That MW Hotchkiss No Longer Needs Operator License SOP-20548-1.Cancellation of License Requested ML18153C2821990-07-0303 July 1990 Requests Exemption from 10CFR50,App J,Paragraph III.A.6(b), Which Requires That When Two Consecutive Periodic Type a Tests Fail to Meet Applicable Acceptance Criteria Type a Test Shall Be Performed at Plant ML20055D4841990-07-0303 July 1990 Requests That Operator Licenses for Listed Individuals Be Cancelled.Licenses No Longer Required ML20055D4831990-07-0303 July 1990 Requests That Operator License for Bl Shriver Be Cancelled. License No Longer Required ML20055D7701990-06-29029 June 1990 Submits Supplemental Response to Violations Noted in Insp Repts 50-338/90-04 & 50-339/90-04 Re Failure to Take Timely Corrective Action for Repair of B Low Head Safety Injection Pump (1-SI-P-1B).No Addl Purchasing Procedure Required ML18153C3591990-06-28028 June 1990 Responds to SALP Repts 50-280/90-16 & 50-281/90-16 for Period 890701-900331.Corrective Actions Focus on Issues of Maint Backlog,Maint planning,post-maint Testing,Staffing & Procurement ML18153C2611990-06-21021 June 1990 Responds to NRC 900522 Ltr Re Violations Noted in Insp Repts 50-280/90-07 & 50-281/90-07.Corrective actions:as-built Configurations of 120-volt Ac & Dc Vital & Semivital Panel Breaker Installations Verified to Be Acceptable ML20043H9421990-06-21021 June 1990 Forwards Proprietary WCAP-12351, North Anna Unit 1 Evaluation for Tube Vibration Induced Fatigue, Per Bulletin 89-001, Failure of Westinghouse Steam Generator Tube Mechanical Plugs. Rept Withheld (Ref 10CFR2.790) ML18153C2591990-06-18018 June 1990 Forwards Response to NRC 900524 Request for Addl Info Re NRC Bulletin 88-004, Potential Safety-Related Pump Loss. Engineering Will Initiate Study to Evaluate Enhancements of Cooldown & Possible Heatup Operation ML18153C2581990-06-18018 June 1990 Forwards Reissued Semiannual Radioactive Effluent Release Rept,Jul-Dec 1989. Rept Contains Info Re SR-89,Sr-90 & Fe-55 Analytical Results for Liquid Composite Samples ML20055C8661990-06-15015 June 1990 Forwards Application for Reissuance of NPDES Permit ML18153C2541990-06-15015 June 1990 Forwards Corrected Tech Specs Page 3.1-3,per Identification of Typo in 900522 Application for Amends to Licenses DPR-32 & DPR-37 ML20043G5711990-06-15015 June 1990 Forwards Response to Request for Addl Info Re Insp Rept 50-339/89-20 Concerning Plant Safety Sys Outage Mod Insp. Response Withheld (Ref 10CFR73.21) ML20043H1131990-06-15015 June 1990 Concludes That Removal of Temporary Loose Parts Monitoring Sys Does Not Increase Probability of Acccident,Create Possibility of New Kind of Accident & Does Not Reduce Margin of Safety ML20043G8731990-06-14014 June 1990 Discusses Evaluation of ASME Section XI Testing for Outside Recirculation Spray Pumps ML18153C2521990-06-14014 June 1990 Responds to NRC 900515 Ltr Re Violations Noted in Insp Repts 50-280/90-09 & 50-281/90-09.Corrective Actions:Abnormal Procedures & Fire Contingency Action Procedures Being Upgraded Via Technical Procedure Upgrade Program ML20043H2091990-06-13013 June 1990 Forwards List of Corrective Actions & Current Status in Response to NRC Bulletin 88-004, Potential Safety-Related Pump Loss. ML20043F4531990-06-0808 June 1990 Forwards, Core Surveillance Rept for North Anna 2,Cycle 7 W/Extended License Burnup Limit. Rept Contains Specific Power Distribution Limits Applicable for Cycle 7 Operation W/Burnup Limit Extension ML18153C2501990-06-0808 June 1990 Confirms That Primary Policy Re Onsite Property Damage Insurance,Provided by Nuclear Mutual Limited 1990-09-07
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Text
e e VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRO INIA 2 3 2 61 W. L. STEWART VICE PRESIDENT NUCLEAR OPERATIONS Mr. Harold R. Denton, Director June 27, 1986 Office of Nuclear Reactor Regulation ATTN: Mr. Lester S. Rubenstein, Director PWR Project Directorate
- 2 Division of PWR Licensing-A U.S. Nuclear Regulatory Commission Washington, DC 20555 Gentlemen:
VIRGINIA ELECTRIC AND POWER COMPANY SURRY UNITS 1 AND 2 NORTH ANNA UNITS 1 AND 2 SUPPLEMENTAL RESPONSE TO GENERIC LETTER 83-28 ITEMS 4.2.1 AND 4.2.2 Serial NO.86-334 NO/JWO/jmj:lDJB-001 Docket Nos: 50-280 50-281 50-338 50-339 License Nos: DPR-32 DPR-37 NPF-4 NPF-7 This letter discusses our proposed improvements to the Reactor Trip Breaker (RTB) Maintenance Programs at our North Anna and Surry Power Stations.
The proposed Maintenance and Testing Program revisions were presented to the NRC staff during our April 7, 1986 meeting in Bethesda, Maryland.
The two revisions to the Program consist of: 1. Reducing the number of repetitive RTB tripping in our maintenance procedures from 38 to 27 cycles and, 2. Extending the frequency of Testing Program from six exceeding 200 breaker activities.
the performance of the RTB Maintenance and months to every twelve months, without cycles between inspection/maintenance In addition, each Westinghouse DB-50 RTB on our Surry and North Anna units will be thoroughly inspected and completely refurbished by Westinghouse at least once per 18 months (with extensions as defined in Technical Specifications) for at least three consecutive intervals.
The refurbishment program will include tolerance checks on operating parts and returning breakers to "as built" or new condition, and testing the RTBs to new breaker specifications.
The first such refurbishment has already been accomplished for our North Anna Units 1 and 2 and is in progress for Surry Unit 1.
e 2 The following paragraphs provide the bases and justification for reducing the number of RTB tripping cycles during maintenance as well as the maintenance frequency.
A. Each of the twenty elements described in the Westinghouse Owners Group (WOG) "Maintenance Program for DB-50 Reactor Trip Switchgear", dated October 14, 1983, with WOG-83-296 cover letter, dated December 15, 1983 will remain in the RTB maintenance program and procedures.
The WOG document specifically states that, "The semi-annual activities (frequencies) might be extended to 9-12 months if (operating) experience shows this to be sufficient, provided that 200 breaker cycles are not exceeded during this interval".
The twenty elements were also addressed in our responses to NRC Generic Letter 83-28, items 4.2.1 and 4.2.2, and in the NRC Safety Evaluations, dated April 24, 1985 for North Anna and May 3, 1985 for Surry, regarding these responses.
The 20 elements remain intact in the RTB maintenance program; only the frequency of the interval or the RTB cycling is decreased.
B. A change to the RTB maintenance program concerning breaker cycling or testing frequency does not involve a change to any present or proposed Technical Specification for Surry or North Anna. C. The company has documented and trended the RTB performance data for over two years and has verified that the operating experience and data has not indicated any adverse trends in RTB performance.
The trending and monitoring of these parameters will continue.
D. Frequently, the semi-annual RTB maintenance must be performed during full power operations, which increases the probability of a reactor trip and the probability of challenges to safety systems. Increasing the time between the maintenance intervals will reduce the opportunity for occurrence of these events without reducing the adequacy of the RTB maintenance program. E. The periodic surveillance testing of the RTBs will continue on a monthly basis at Surry and bimonthly at North Anna (staggered testing).
This testing cycles each RTB, measures the breaker response time (Surry only), and independently verifies operability of the undervoltage trip attachment (UVTA) and the shunt trip at both sites. The system response time is measured during refueling outages at North Anna in accordance with Technical Specification requirements.
F. Our experience indicates that excessive cycling of the RTB reduces the effectiveness of lubrication and increases the wear on RTB components.
For example, the alcohol-based molybdenum disulfide UVTA lubricant tends to fall off the UVTA during the energetic opening of the breaker, following evaporation of the alcohol. The finely ground molybdenum disulfide ore can be observed collecting as dust in the breaker, beneath the UVTA and is a primary reason for the implementation of the monitoring and lubricating program every 200 cycles. We have also observed wear on the auxiliary contacts and its latching arm following the repetitive racking in and out operations required by the maintenance and testing programs.
In addition, the energetic and repetitive cycling of the RTB's is hypothesized as the cause, for losing one of the seven spring clip type lock rings from the grooved ends of the UVTA pivot and latch pins. Two of the three UVTA "failures" that occurred during testing at our Surry .I 3 facility after 1981 were due to the loss of a small lock ring which permitted latch or pivot pin displacement and binding of the UVTA. (The third failure was apparently due to an improperly machined UVTA latch pin). Our maintenance procedures require a visual inspection of the lock rings to ensure they are in place and secure. Preoperational inspections and testing of new UVTA's is also performed to ensure operability.
G. Element 17 in the WOG program, "Westinghouse Maintenance Program for DB-50 Reactor Trip Switchgear", identifies the functional RTB check prior to returning the breaker to service. This check closes and trips the breaker electrically and manually to demonstrate that breaker functions including closing, shunt tripping and undervoltage tripping (10 UV trips) are normal. We can determine no firm basis for the 10 undervoltage trips, other than the fact that newly manufactured DB-50 breakers are tripped 10 times by Westinghouse to verify proper operation of the new breaker. After reviewing the comprehensive inspections and testing which we frequently perform on the DB-50 RTBs, we have determined that 10 RTB cycles is excessive.
Subsequent to cycling the RTB 25 times during our periodic Maintenance and Testing Program, we will cycle the RTB two more times to complete the functional check of the RTB prior to returning it to service. Our procedures will, of course, ensure that the breaker or components will be cycled several times whenever cleaning and lubrication are performed (page 39 of WOG Procedure).
H. Handling of the RTBs is excessive.
Every 6 months, the RTBs must be racked out and removed from their respective cubicles to perform maintenance and testing. The likelihood of electrical or mechanical damage to the breaker and its components increases with the frequency of handling.
Similarly, the chance for human error increases when the equipment maintenance and testing increases.
In fact, while the design, maintenance, and testing of the RTBs have been improving (e.g. Auto shunt trip, lubrication techniques, response times, etc.) to increase the reliability of the RTB, the probability for human error or accidental component damage has actually increased due to the frequency of the work and the man-hours involved.
We hope to reduce the risk of human error by reducing the frequency of the RTB maintenance.
Implementation and monitoring of this program will increase the reliability of the Reactor Trip Breakers.
I. As indicated in WCAP-10852, "Report of the DB-50 Reactor Trip Breaker Shunt and UVTA Life Cycle Tests", the shunt trip attachment appears to be a simple and reliable tripping device for the DB-50 RTB. The automatically actuated shunt trip feature has been installed at Surry and North Anna and is routinely tested to verify operability.
The shunt trip attachment on each RTB is also inspected to ensure that the trip lever to trip bar clearance is between 0.031 and 0.125 inches. With the addition of the automatic actuation of the shunt trip attachment, diverse features exist to effect a reactor trip for each RTB. Initially, we were hoping to reduce the number of RTB cycles per year by over 50%; however, after reviewing WCAP-11092 (October 29, 1985 RTB failure at D.C. Cook) and discussing it with members of your staff, we have decided to perform limited testing of our RTBs prior to shipment to Westinghouse for refurbishment.
The RTBs will be tested again when they are returned to the 4 site to measure and record RTB performance data and verify operability.
This data is also important to ensure that any problems which may occur during shipping or handling are promptly identified and corrected.
We are currently working with Westinghouse on the design and fabrication of a molded and cushioned, form-fitting RTB container which would be environmentally sealed during shipment.
The test data would therefore monitor performance of the container and transportation procedures.
The RTB containers could also be used on site to store spare RTBs, as required.
However, the extension of the RTB Maintenance and Testing Program to 12 month intervals should in itself improve the reliability of the Reactor Trip Breakers.
Perhaps the most significant point of our proposed RTB refurbishment and Maintenance and Testing Programs is that the communications and exchange of information between Westinghouse and the Company will be enhanced.
For example, our engineers have observed RTB testing at the Westinghouse facilities and Westinghouse Senior Breaker Engineers have participated in RTB Committee meetings in Virginia.
This team effort by vendor and user will help to ensure reliable Reactor Trip Breaker operation.
We plan to implement our proposed revisions to the RTB Maintenance and Testing Programs within the next 90 days at our Surry and North Anna facilities.
If you require additional information or have any questions, please contact us. Very truly yours, ti~% W. L. Stewart Attachments cc: Dr. J. Nelson Grace Regional Administrator Region II NRC Senior Resident Inspector North Anna Power Station NRC Senior Resident Inspector Surry Power Station Mr. L.B. Engle NRC North Anna Project Manager PWR Project Directorate
- 2 Division of PWR Licensing-A Mr. C. Patel NRC Surry Project Manager PWR Project Directorate
- 2 Division of PWR Licensing-A