ML19259A638

Notifies That Initial Review of Systematic Evaluation Program Safety Topic V-11.A Is Completed.Forwards Table of Docketed Info on Reactor Coolant Sys Interfaces W/Low Pressure Sys & Plant Info Obtained During Safe Shutdown

ML19259A638
Person / Time
Site:	Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date:	12/21/1978
From:	Ziemann D Office of Nuclear Reactor Regulation
To:	Counsil W CONNECTICUT YANKEE ATOMIC POWER CO.
References
TASK-05-11.A, TASK-5-11.A, TASK-RR NUDOCS 7901080359
Download: ML19259A638 (8)

Text

[

UNITED STATES y

~g NUCLEAR REGULATORY COMMISSION j

WASHINGTON, D. C. 20565 x,

e

' k

.,/

December 21, 1978 Docket No. 50-213 Mr. h. G. Counsil, Vice President Nuclear Engneering and Operations Connecticut Yankee Atomic Power Company Post Office Box 270 Hartford, Connecticut 06101

Dear Mr. Counsil:

RE: VERIFICATION OF PLANT INFORMATION ON SEP TOPIC V-ll.A,

" REQUIREMENTS FOR ISOLATION OF HIGH AND LdW PRESSURE SYSTEMS" Our initial review of SEP Safety Topic V-ll.A has been completed. The enclosed table presents docketed infonnation on reactor coolant system interfaces with low pressure systems. Also included is plant information obtained during our recent safe shutdown review of your facility.

Only systems that had direct interfaces with the primary system were considered. These were the water cleanup systems, the ECCS, the sampling systems, and the RHR systems. High pressure systems connected to the primar,' system that indirectly interfaced with a low pressure system (i.e., service water or component cooling through a heat exchanger) were not considered. Systems designed to operate at high pressure were also not included (i.e., BWR isolation condenser) except for the high pressure RHR system on several BWRs, which were included for completeness.

For PWRs the seal injection system was included because it was identified in a memo ' rom E. G. Case to R. F. Fraley (Ref.1) as having the potential to inadver antly overpressurize the water makeup tank. For BL'Rs the reactor vessel head spray cooling system was included because the potential for overpressurizing the condensate storage tank, if not properly vented, may exist.

790108o357

Mr. W. G. Counsil December 21, 1978 Isolation requirements for the ECCS system injection lines as stated in Standard Review Plan (SRP) 6.3 are listed below:

(1) One or more check valv's in series with a normally closed motor-operated valve. The motor-operated valve is to be opened upon receipt of a safety injection signal once the reactor coolant pressure has decreased below the ECCS design pressure.

(2) Three check valves in series.

(3) Two check valves in series, provided that there are desig..

provisions to permit periodic testing of the check valves for leak tightness and the testing is performed at least annually.

The isolation requirements for the RHR system as stated in Bran'h Technical Position BTP-RSB 5-1 are listed below:

(1) The following shall be provided in the suction side of the RHR system to isolate it from the RCS.

(a)

Isolation shall be provided by at least two power-operated valves in series. The valve positions shall be indicated in the control room.

(b) The valves shall have independent diverse interlocks to prevent the valves from being opened unless the RCS pressure is below the RHR system design pressure. Failure of a power supply shall not cause any valve to change positions.

(c) The valves shall have independent diverse interlocks to protect against one or both valves being open during an RCS increase above the design pressure of the RHR system.

(2) One of the following shall be provided on the discharge side of the RHR system to isolate it from the RCS:

(a) The valves, position indicators, and interlocks described in item 1(a) - (c),

(b) One or more check valves in series with a nonnally closed power-operated valve. The power-operated valve position shall be indicated in the control room.

If the RHR discharge line is used for an ECCS function, the power-operated valve is to be opened upon receipt of a safety injection signal once the reactor coolant pressure has decreased,

Mr. W. G. Counsil December 21, 1978 (c) Three check valves in series, or (d) Two check valves in series, provided that there are design provisions to permit periodic testing of the check valves for leak tightness and the testing is performed at least annually.

Isolation requirements for the cleanup and sampling system are dictated by the requirements of SRP 6.2.4 and GDC 55 related to lines that pene-trate the primary containment boundary and are listed below:

(1) One locked closed isolation valve--inside and one locked closed isolation valve outside containment; or (2) One automatic isolation valve inside and one locked closed isolation valve outside containment; or (3) One locked closed isolation valve inside and one autcmatic isolation valve outside containment; or (4) One automatic isolation valve inside and one automatic isolation valve outside containment.

The table indicates (1) if the systems meet the isolation requirements identified; the types of valves used, (2) if the capability for leak testing individual valves exists, (3) the high pressure low pressure interfaces, (4) method of pressure reduction in closed loop systems and (5) how the systems are isolated (by procedures or automatically).

Check valve orientation was included because there has been some recent concern that vertically mounted check valves are not as effective as those mounted horizontally. There was, however, no data in the FSARs on check valve orientation.

For isolation of the systems identified to meet current criteria, they must satisfy conditions in the appropriate SRPs, GDC 55 and Section XI of the ASME Code. These documents establish the combinations of accept-able valves, the tasting interval, and the individual valve leak te= Lins requirements.

8

,Mr. W. G. Counsil December 21, 1 978 To meet SEP schedule requirements, we need your verification of the correctness of the data presented in the enclosed table and all additional infomation you may have pertaining to Safety. Topic V-11.A by January 29, 1979.

Sincerely, h' ?.

DennisL.Ziemann), Chief y),yvrn; /L v ! % '"'

Operating Reactors Branch #2 Division of Operating Reactors

Reference:

Memo:

E. G. Case to R. F. Fraley, Executive Director ACRS, dated July 11, 1977.

Subject:

" Isolation of Low Pressure Systems from Reactor Coolant System".

Enclosure:

As stated cc w/ enclosure:

See next page

+,.,

s '

h Mr. W. G. Counsil December 21, 1978 q

cc Day, Berry & Howard Counselors at Law One Constitution Plaza Hartford, Connecticut 061 03 Superintendent Haddam Neck Plant RFD #1 Post Office Box 127E East Hampton, Connecticut 06424 Russell Lit;.cy 119 Broad Street Middletown, Connecticut 16457 1

s Mr. James R. Hininelwricht Post Office Box 270 Hartford, Connecticut 06101

^

i 5

s I

M

._ Y K

____.....-....._._..._..,...-..._...._...y, 1

En et

PLANT: Haddam Neck (Conn. Yankee)

Evaluation of Isulation of Ic t Pressure Systeos From Reactor Coolant System Meets Redundancy Testable Location of Method of Ofrect Interfaces *4 Isolatio9 of Type Between HP/LP Check Valve Pressure Method of 3

Criteria isolation Valves Valves Interface Orientation Reduction Isolation Remarks 6

idater Cleanup System Inlet Yes 1HO &

No One valve inside &

NA Orifice DWG 248041 (FSAR) 8 1 Manual one outside Discharpes Yes IMO &

No Inside containment NA Discharges to CVCS 1 Check charging line l

Seal Injection Systee,5 ECCS*

IMO &

Low Pressure Yes No Inside containment NA See remarks under RHR Injection l Core discharge elay)

I Accumulators No accumulators Sampilng Systes Yes IMO &

No One valve it. side NA Throttling Procedural 4 types of sampling lines -

1 Hanual and one outside valve down steam & Ifquid pressurizer containment except stream of space, hot leg & loop drain for loop drain lines isclation press.' Steam space line which are outside valves except normally open directly to containment for pressurizer CVCS (CWG 298042) steam space line which uses capillary tube RIR System Yes 2MO No Inside containment NA NA Outboard Taction Side valve key-lock contro11ed Uigh press-ure inter-lock on in-a board valve (prevents open-ing, does not auto shut.)

• HPSI design press is 1500 psig, e

s PIANT: Haddas Neck (Conn. Yankee)

Evaluattor. of Isolation of ice Pre ssure.ystems From Reactor Coolant System (Con't)

Meets Redundancy Testable Location of Method of 91 rect Interfaces *4 Isolatio9 of Type Setween HP/LP Check Valve Pressure Method of 3

Criteria Isolation Valves Valves Interface Orientation Reduction Isolation Remarks Discharge Side Yes 2M0 No Inside contairment NA Outboard Low pressure sakty in-(RHR) valve key-jection systems and RHR lock con-system share same dis-trolled.

charge lines and there-High press-fore have common DWG ure inter-298044 (FSAR). Core lock on in-delays MOV opens on board valve receipt of SI signal.

(preventsopen-ing, doeg not auto, shut.)

e

e t

i NOTE:

1. PWRs only

2. BWRs only 8

3. Only direct interfaces considered--service water and component cooling water systems not evaluated t'

4. High pressure systems (i.e., control rod drive hydraulic, isolation condenser, standby liquid control, i,

high pressure injection, & RCIC) connected to reactor coolant pressure boundary not evaluated

5. Inadvertent overpressurization of makeup tank due to reactor coolant pump seal leak off

6. Reactor water cleanup system for BVRs and CVCS or Letdown System for PWR5

7. Isolation requirements for ECCS specified in SRP 6.3 (Section III), for RHR system in BTP RSB 5-1

. attached to SRP 5.4.7 and for water cleanup and sampling system in GDC 55

8. NA - Not Applicable I

y 0

1 S

I

=

ee

.