ML20009A029

Application for OL Amend,Revising Tech Specs to Allow 72-h Exemption from Containment Oxygen Concentration Requirement

ML20009A029
Person / Time
Site:	Brunswick
Issue date:	06/29/1981
From:	Utley E CAROLINA POWER & LIGHT CO.
To:	Ippolito T Office of Nuclear Reactor Regulation
Shared Package
ML20009A030	List: ML20009A029 ML20009A032
References
NO-81-1105, NUDOCS 8107070393
Download: ML20009A029 (3)

Text

, v

'~ ~

CP&L Carolina Power & Light Company June 29, 1981 File: NG-3514(b) Serial No.: NO-81-1105 Office of Nuclear Reactor Regulation t-ATTENTION: Mr. T. A. Ippolito, Chief h Operating Reactors Branch No. 2 United States Nuclear Regulatory Commission h

lj(

e[

f .g Washington, D. C. 20555 S,-

gUL O G i98w Q,q BRUNSWICK STEAM ELECTRIC PLANT UNIT NO. 2 h Mg,ammum

• DOCKET NO. 50-324 VA LICENSE NO. DPR-62 / U REQUEST FOR LICENSE AMENDMENT $* j CONTAINMENT OXYGEN CONCENTRATION N 4

SUMMARY

In accordance with the Code of Federal Regulations, Title 10, Section 50.90 and Section 2.101, Carolina Power & Light C.mpany (CP&L) hereby requests revisions to the Technical Specifications for its Brunswick Steam Electric Plant (BSEP) Unit No. 2. Thes6 changes would allow an exemption for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> from the containment oxygen concentration Technical Specification LCO 3.6.6.3. This was discussed with NRC staff on June 28-29, 1981. This change is necessary to allow Brunswick-2 to operate until repairs can be made to a rupture in the Containment Attrospheric Control (CAC) inerting line which is common to both units.

DISCUSSION During a startup sequence, Brunswick-2 sached 15% power 'evel at 6:30 a.m. on June 28, 1981. We began to inert coi:".ainment at about 11:00 a.m.

using the CAC system. However, at 12:10 p.m., June 28, the CAC inerting line experienced a rupture downstream of the vaporizer valve. This event terminated the inerting procedure and caused Brunswick-2 to be unable to reach 4% oxygen concentration by 6:30 a.m. on June 29 as required by Technical Specifications.

1 0 eio7o7o393 810629 n g) e 6

DR ADOCK 05000 g i -

yit ayenege SUeet

• P. O. Box 1551

• Ral9 gh. N. C. 27602

nes -

Mr. T. A. Ippolito June 29, 1981 v

A temporary repair has been installed on the CAC inerting line, and inerting is presently in progress on Brunswick-2. If no problems are encountered with the temporary repair, the Brunswick-2 containment atmosphere should be inerted to less than 4% oxygen concentration by noon time on June 29. Oxygen concentration would then be maintained by the Containment Atmospheric Dilution (CAD) System while CAC is taken out of service for permanent repairs. These repairs would begin during the afternoon of June 29 and would require about 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

Erunswick-1 is scheduled to start up on June 30, 1981, and a similar Technical Specification change may be needed for this unit. If this proves to be necessary, it will be handled separately.

SAFETY EVALUATION The following safety considerations have been evaluated in preparation of this Technical Specification change request:

(1) The probability of occurrence of a LOCA during the 72-hour exemption period is extremely renote. Present Technical Specifications allow deinerting for a total of two days during and after a shutdown, and

, the time period requested by this change will present no significant additional safety hazard.

(2) CP&L is operating the Brunswick containment purging system in accordance with NRC's October 22, 1979 " Interim Position on

Containment Purging and Venting." The purge isolation valves are capable of closing against the dynamic forces of a L7CA.

( 3) Regulatory Guide 1.7 Revision 2 discusses product.- af combustible gases resulting from a LOCA and states that hydrogea concentrations would reach flammable limits within a day to a month after a LOCA.

The CAD System at the Brunswick Plant is fully qualified (seismic, safety-related) and is designed to maintain containment inerted following a LOCA. The CAD System can be operated to inject nitrogen into containment to dilute combustible gases after a LOCA.

CP&L commits to utilize this system as a combustible gas control measure if a LOCA were to occur during the period Brunswick-2 operates deinerted.

(4) The latest edition of Standard Technical Specifications (STS) for BWR-4 plants allows deinerted operation for 120 Effective Full Power days during the Startup Test Program. This is a significantly longer time period than the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> being requested for Brunswick-2.

(5) With regard to fire protection considerations for operating in a deinerted condition, the plant fire brigade will be alerted to the degraded fire protection condition in containment.

o. .

Mr. T. A. Ippolito June 29, 1981 ADDITIONAL CONSIDERATIONS Brunswick Plant is convening a meeting to study this even~ and determine its root cause so that a solution can be expedited. In addition, Brunswick Plant will station an operator at the local CAC control station each time inerting via CAC is in progress. This will provide prompt notification to operations personnel in case of a recurrence and will allow additional surveillance during inerting operations.

CON (:URRENCE This Technical Specification change request and its safety justifications have been reviewed and concurred with by both the on-site safety review group (Plant Nuclear Safety Committee) and the off-site safety review group (Corporate Nuclear Safety Unit).

CONCLUSION It is CPEL's intent to inert the Brunswick-2 containment as soon as possible. Since Technical Specifications require oxygen concentration to be less than 4% within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after exceeding 15% of rated thermal, power, we request an expedited review of this request.

Attached you will find the revised Technical Specifications page with the changes indicated by vertical lines in the right-hand margin. We believe that this request involves a single technical issue and thus constitutes one Class III amendment in accordance with 10CFR170.22.

Accordingly, our check for $4000 is enclosed.

Should you have any questions regarding this matter, please contact my staff.

Yours very truly, E.E.Utley)

Executive Vice President Power Supply and Engineering & Construction JAM /je (N#62)

Attachments Sworn to and subscribed before me this -

29th day of June, 1981.

Erni ~ e Gs L Notary Publicz My commission expires: g

-___- - -