ML20062H236

RCS Vents, Technical Evaluation Rept

ML20062H236
Person / Time
Site:	Browns Ferry
Issue date:	06/02/1982
From:	Barnhart B, Butcher E LAWRENCE LIVERMORE NATIONAL LABORATORY
To:	Office of Nuclear Reactor Regulation
Shared Package
ML20062H235	List: ML20062H236
References
CON-FIN-A-0246-2, CON-FIN-A-246-2, RTR-NUREG-0737, RTR-NUREG-737, TASK-2.B.1, TASK-TM NUDOCS 8208130448
Download: ML20062H236 (4)

Text

.

g

LAWRENCE LIVERMOFiE LABORATORY Operating Reactor - TMI Lessons Learned NUREG-0737 Response Evaluations (Program II) l' Project 1 - Reactor Coolant System Vents (Item II.B.1)

NRC FIN A0246-2 4

i a

FINAL TECHNICAL EVALUATION REPORT FOR BROWNS FERRY 1, 2, and 3 li i

i Prepared by Energy Incorporated - Seattle for Lawrence Livermore National Laboratory under. contract to the NRC Office of Nuclear Reactor Regulation, Division of Licensing, i

. .t DL Cognizant Manager - Ed-Butcher DL Project Manager - Beverly Barnhart l:

NOTICE "This report was ared as an account of work sponsored by th '

nited States Government.

Neither the United States nor the' United States Department of Energy, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or respon- ,

sibility for the accuracy, completeness or usefulness of any information, apparatus, product or process disclosed, or represents that its use would not ininnge privately-owned rights."

June 2, 1982 l

8208130448 820802 PDR ADOCK 05000259 P PDR

• E~.r Crm:rtEmovy Ikun:yo!Cadyra PO 63v 80'? Lw-orse Cttvna 94550 Tc'rttoneH1Sr4221100 Tws 910-386 8339 UCLLL LVMR l

I.

Docket Numbsrs 50-259,50-260, and 50-296 l ~

NRC TAC Numbers 44355,44356, and 44357 i 1 l 1 TECHNICAL EVALUATION REPORT

! ON REACTOR COOLANT SYSTEM VENTS 4

l FOR BROWNS FERRY I,2, AND 3

(  ;

INTRODUCTION i

i The requirements for Reactor Coolant System High Point Vents are stated in porograph l

{ (CX3Xiii) of 10 CFR S0.44, " Standards for Combustible Gos Control System in Light

i Water Cooled Power Reactors," and are further described in item II.B.I of NUREG-0737, jl '

"Clorification of TMI Action Plan Requirements." In re:rponse to these and previous

+

j requirements, the Tennessee Valley Authority has submitted information in References I

and 2 in support of the vent system on Browns Ferry Nuclear Plant Units I,2, cnd 3.

f,

'f

. [

't EVALUATION  !

i The function of the reactor coolant systeri[(RCS) vent system is to vent noncondensible l I

gases from the high points of the RCS to assure that core cooling during natural circulation will not be inhibited. The Boiling Water Reactor (BWR) Owners' Group Ims submitted documentation'(References 3 through 6) on how the RCS venting requirements

i are met in General Electric (GE) BWRs. The BWR Owners' Group position has been

!i ,

endorsed by the licensee.

.q ,

i 1 in occordance with the BWR Owners' Group position, the primary means of venting

,j.

'j noncondensible gases from the reactor pressure vessel at Browns Ferry 1,2 and 3 ore six I power-operated, safety-grade automatic depressurization system (ADS) safety / relief I, volves which alone provide adequate venting. -

i i We have reviewed design information on the volves ossociated with the obove system  ;

i that will serve os RCS vents and confirmed that they are operable from the main control '

i room. We have also determined that the volves are provided with emergency' power and that a degree of.redundoney in the RCS vent system is provided by powering different vent paths from different emergency buses. NRC has previously verified that the i

?

p e

---

,---,.---wwy - ., - -.--,,-,.ww - . - - - - . - - - ,,..,+-.---we-,e--- -

i safety / relief volves are provided with positive position indication in the main control room (Reference 7). Additional RCS venting occurs at the high pressure coolant injection (HPCI) and reactor core isolation cooling (RCIC) system turbine exhausts. The j licensee has also verified that no protection system that is necesscry to maintain adequate core cooling requires remote venting since none are susceptible to the. buildup 1 of a large amount of noncondensible gas that could cause c loss of function of these systems.

CONCLUSION We conclude, based on the applicability of the BWR Owners' Group position to Browns Ferry 1, 2, and 3 and our specific review of the Browns Ferry 1,2, and 3 design, that the existing systems at Browns Ferry 1, 2, end 3 are sufficient to effectively vent noncondensible gases from the RCS and meet the requirements of NUREG-0737 Item II.B.I and paragraph (cX3Xiii) of 10 CFR 50.44. We therefore recommend that the Browns Ferry 1,2, and 3 RCS venting capability be found acceptable by NRC contingent on NRC review and approval of the existing operating procedures and technical specifications for use of the existing systems',os RCS vents.  !

I l-1 1.

i I

I i

i

l 1

1 REFERENCES l

1 l 1

1. Letter, L.M. Mills (Tennessee Valley Authority) to D.G. Eisenhut (NRC), dated October 17, 1979.

2. Letter, L.M. Mills (Tennes:ee Valley Authority) to D.B. Vossallo (NRC), dated d

May 4,1982.

l

3. Letter, T.D. Keenan (BWR Owners' Group) to D.G. Eisenhut (NRC), "BWR Owners' Group Positions on NUREG-0578," dated October 17, 1979.

D.G. Eisenhut),

4. Letter, D.B. Waters (BWR Owners' Group) to NRC (Attn:

" Preliminary Clarification of TMI Action Plan Requirements - BWR Owners' Group Comments," dated October 8,1980.

S. General Elc-tric Report NEDO-24708A, Revision I, " Additional Information Required for NRC Staff Generic Report on Boiling Water Reactors," dated Dccember 1980.

D.G. Eisenhut), f

6. Letter, D.B. Waters (B'WR Owners' Group) to NRC (Attn:

"NUREG-0660/0737 Requirement II.B.1: Reactor Coolant System Vents," dated i April 24,1981.

{

i

7. NUREG-0737," Clarification of TMI Action Plan Requirements," item II.D.3," Direct Indication of Relief- and Safety- Valve Position," dated November 1980. l i

(

[

e e

w.

+---w--- - - - - . . - . . ,. - _. . .