Letter Sequence Other |
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Results
Other: 05000266/LER-1979-010-01, /01T-0 on 790620:plant Safeguards Actuation Circuitry Review Indicated Need for Circuitry Changes.Caused by Changes in IEEE Std Since Plant Design.Mods to Four Applicable Safeguard Circuits Will Be Performed, ML19210C482, ML19242D259, ML19253A712, ML19253B006, ML19257A367, ML19257B511, ML19289C679, ML19310A971, ML19323H481, ML19345H544, ML20010E141, ML20027A527, ML20038C635, ML20039A258, ML20040F029, ML20065R665
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MONTHYEARML20027A5271978-11-28028 November 1978
Discusses Possible Dangers of LOCA in Containment Purging During Normal Plant Oper.Requests Either Commitment to Limit Purging or Justification for Continuing.W/Encl ANO 7812080207
Project stage: Other
ML19289C6791979-01-16016 January 1979
Responds to Re Purging During Normal Operation. Need for Purging Has Been Limited,But It Is Essential That Capability of in-containment Activities at Power Be Maintained
Project stage: Other
05000266/LER-1979-010-01, /01T-0 on 790620:plant Safeguards Actuation Circuitry Review Indicated Need for Circuitry Changes.Caused by Changes in IEEE Std Since Plant Design.Mods to Four Applicable Safeguard Circuits Will Be Performed1979-07-0303 July 1979
/01T-0 on 790620:plant Safeguards Actuation Circuitry Review Indicated Need for Circuitry Changes.Caused by Changes in IEEE Std Since Plant Design.Mods to Four Applicable Safeguard Circuits Will Be Performed
Project stage: Other
ML19253A7121979-08-0808 August 1979
Confirms Action Taken as Result of 790803 Telcon Re Util Request to Leave Containment Purge Values Closed Above Cold Shutdown Condition.Proposal Acceptable on one-time Basis
Project stage: Other
ML19242D2591979-08-10010 August 1979
Appreciates Prompt Approval of Request to Purge Containment. Approval Reduced Personnel Inconvenience & man-rem Exposure. Will Pursue Review of Containment Purge Sys
Project stage: Other
ML19253B0061979-09-0606 September 1979
Discusses Containment Purge Valve Operations.Notifies of Potential Mods to Ensure That Valves Will Close Against Containment Pressure Transients.Consultants Will Conduct Studies & Analyses of Potential Mods
Project stage: Other
ML19323H4811979-09-30030 September 1979
Technical Evaluation of Electrical Instrumentation & Control Design Aspects of Override Containment Purge Valve Isolation & Other Engineered Safety Feature Signals for Point Beach Nuclear Power Station,Units 1 & 2
Project stage: Other
ML19210C4821979-11-0101 November 1979
Responds to Re Guidelines for Operability of Containment Purging & Venting Valves During Normal Operations.Evaluation Will Consider Consultant Studies of Potential Mods to Valves
Project stage: Other
ML19257A3671979-11-19019 November 1979
Forwards Interim Position on Containment Purging & Venting During Normal Operation Pending Resolution of Isolation Valve Operability.Commitment to Comply W/Encl Position Should Be Submitted within 45 Days
Project stage: Other
ML19310A9711979-12-27027 December 1979
Requests Preliminary Evaluation of Licensee Response to NRC 791023 Interim Position for Containment Purge & Vent Valve Operation Pending Resolution of Isolation Valve Operability, Generic Item B-24.Evaluation Form Encl
Project stage: Other
ML19257B5111980-01-0909 January 1980
Provides Commitments Sought in NRC .Forwards to Bechtel Re Purge Valve Capability Verification.Nrc Guidelines Will Be Considered During Evaluation of Mods for Improved Purge Valve Reliability
Project stage: Other
ML19257C8081980-01-11011 January 1980
Forwards Safety Evaluation to Be Substituted for Encl in Ltr Per Agreement Reached at 791213 Meeting Re Containment Purge
Project stage: Approval
ML19257C8101980-01-11011 January 1980
Safety Evaluation Approving Electrical,Instrumentation & Control Design Aspects of Override of Containment Purge Valve Isolation,Except Radiation Monitors Used to Initiate Containment Purge Isolation
Project stage: Approval
ML19323H4781980-05-22022 May 1980
Forwards Safety Evaluation Supporting Design Aspects of Containment Purge Valve Isolation Override & Other Engineered Safety Feature Actuation Signals Except Radiation Monitors Which Initiate Containment Purge Isolation
Project stage: Approval
ML19345H5441981-05-0707 May 1981
Documents Basis for Containment Isolation Pressure Setpoint Reported in Item II.E.4.2 of NUREG-0737 Response Per NRC 810414 Telcon.Present 5 Psig Setpoint Considered Realistic & Appropriate
Project stage: Other
ML20008F4471981-07-21021 July 1981
IE Info Notice 81-21, Potential Loss of Direct Access to Ultimate Heat Sink. Provides Addl Info to IE Bulletin 81-03
Project stage: Request
ML20038C6351981-07-31031 July 1981
Srp,Revision 2 to Section 6.2.4, Containment Isolation Sys
Project stage: Other
ML20010E1411981-08-28028 August 1981
Proposed Tech Spec Revision Pages 15.3.6-2,15.3.6-3, 15.4.4-12,15.4.4-15 & 15.4.4-15a Re Testing of Containment Purge Supply & Exhaust Sys Isolation Valves
Project stage: Other
ML20010E1361981-08-28028 August 1981
Application for Amend to Licenses DPR-24 & DPR-27 Submitted as Tech Spec Change Request 68 to Incorporate Addl Restrictions Re Use & Testing of Containment Purge Supply & Exhaust Sys Isolation Valves,Per NRC Request
Project stage: Request
ML20033C0321981-11-23023 November 1981
Second Discovery Progress Rept for Period Ending 811122,per ASLB 811113 Memorandum Order.Licensee 811027 Responses to Wi Environ Decade 811023 Interrogatories Are Not Fully Responsive.Certificate of Svc Encl.Related Correspondence
Project stage: Request
ML20039B0181981-11-24024 November 1981
Requests That Util Remit Class III Fee for Unit 1 & Class I Fee for Unit 2 to Cover Review of 810828 Application for Tech Spec Changes Re Containment Purge Valve Operability
Project stage: Approval
ML20033A9071981-11-24024 November 1981
Advises of Significant Error in 811117 Telcon Transcript
Project stage: Request
ML20039A2581981-12-0707 December 1981
Requests That NRC Reconsider Requirement of Class III Approval Fee During Final Review Re Tech Spec Change Request 68.Changes to Tech Specs Result of NRC Request.No Approval Fee for Amend Review Necessary
Project stage: Other
ML20040F0291982-01-28028 January 1982
Proposed Tech Spec 15.3.6 Re Containment Purge Supply & Exhaust Valves
Project stage: Other
ML20040F0221982-01-28028 January 1982
Application for Amend to Licenses DPR-24 & DPR-27,consisting of Tech Spec Change Request 68 Re Containment Purge Valve Operability
Project stage: Request
ML20065R6651982-10-22022 October 1982
Provides Results of Confirmatory Analysis Demonstrating That Unacceptable Radioactive Release from Containment Would Not Take Place as Result of Small Break LOCA in Which Operator Action Required.Radioactive Release Negligible
Project stage: Other
1980-01-11
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\\s_,s) wisconsin Electnc voua couvany 231'A EST MICHIGMt MIL A AUKE E, WISCONSIN 53201 January 16, 1979 Mr. IIarold R. Denton, Director Office of Nuclear Reactor Regulation U.
S.
NUCLEAR REGULATORY COMMISSION Washington, D.
C.
20555 Attention:
Mr.
A.
Schwencer, Chief Operating Reactor Branch 1 Gentlemen:
DOCKETS 50-266 and 50-301 CONTAINMENT PURGING DURING NORMAL PLANT OPERATIONS POINT BEACll NUCLEAR PLANT UNITS 1 AND 2_
This is in reply to your letter of November 28, 1978 in respect to containment purging during normal operation.
In that letter you cclled attention to events relating to containment purging w erations, and raised questions concerning possible failure of purge line valves, requesting we take certain alternative actions in response.
You also requested that we review safety actuation signal circuits, incorporating manual override or bypass features to assure that overriding of one safety actuation signal does not also bypass any other safety actuation signal.
We regret that our reply has been delayed, but the nature of the matters raised in your letter involves substantial review and analysis, which we have been unable to complete.
We are continuing to examine the issues raised in your November 28 transmittal, and will respond more fully at a later date.
In the meantime, we present herewith our interim reply.
In respect to containment purging, we have found at Point Bec.ch that extended activities inside containment with a reactor at power or in hot shutdown are infrequent.
Accordingly, the need for purging at our facility has been limited.
Nevertheless, we believe it is essential that the capability of in-containment activities at power be maintained.
This requires containment
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p purging if personnel exposures are to be minimized.
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Mr. Ilarold R.
Denton January 16, 1979 You suggested three options governing such containment purging activities.
We have requested design and analytical data from the manufacturer of our purge isolation valves.
Pending receipt of these data, we are unable to determine which of the options you offered would be appropriate to Point Beach.
In the interim, we will continue to limit purging to the minimum necessary.
A brief description of the actuation system at Point Beach follows.
The containment purge inlet and outlet valves are automatically closed by a containment ventilation isolation signal.
The containment ventilation isolation signal is formed by an OR function of the following signals:
High Containment dadiation Safety Injection Manual Spray Manual Containment Isolation A reset or override function is provided on the containment ventilation isolation signal.
If any of the above-listed input signals are continuously present and it is desired to open the centainment purge inlet and outlet valves, this can be done by pressing the reset button.
The reset circuit contains a seal-in which prevents reactivation of containment ventilation isolation by another input signal as long as the original input is continuously present.
As soon as the input signal is interrupted, the seal-in is dropped and any of the input signals will again generate the containment ventilation isolation signal.
Thus, for example, if a high containment radiation signal is continuously present, the purge inlet and outlet valves could be opened by resetting the containment ventilation isolation signal.
Under these conditions, a safety injection signal would not reclose the valves.
The valves can be reclosed manually from the control room.
Presence of reset on the containment ventilation isolation signal is not presently annunciated.
Reset of the containment ventilation isolation signal does not affect any other signal.
In particular, it does not affect actuation of the containment (fluid) isolation signal or the safety injection signal.
A review of past operating experience with the containment purge system verifies that the inlet and outlet valves have never been opened using the reset capability to bypass one safety actuation signal in order to open the valves.
When the high radiation signal has been present, it has been adjusted upward from its initial conservatively low setpoint until it is cleared.
The purge inlet and oatlet valves are opened by pushing the reset function and opening the valves.
Should any safety actuation signal occur while the valves are open, they would close automatically.
This mode of operation will continue until the system can be modified, if required, to remove the bypassing of other safety actuation signals when the system is reset with an actuation signal present.
.e Mr. Ilarold R. Denton January 16, 1979 We will provide to you, in approximately 90 days, our review of the design of the remaining safety actuation circuits and a schedule for the development of any design or procedural changes planned to assure correction of any non-conforming circuits.
Very truly yours, Exec tive Vice President Sol Burstein
