ML20212M112

Safety Evaluation Granting Relief from Inservice Insp Program Hydrostatic Pressure Test Requirements of Svc Water Sys,Per Util 860617 Request

ML20212M112
Person / Time
Site:	Zion  File:ZionSolutions icon.png
Issue date:	08/20/1986
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20212M095	List: ML20212M090 ML20212M112
References
NUDOCS 8608250380
Download: ML20212M112 (3)

Text

. r 8 \o -

UNITED STATES

• NUCLEAR REGULATORY COMMISSION

{ ,fr wAsHawoTow, n. c. noses

%,*****p$

t SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION

'RELATED'TO' OPERATION OF ZION NUCL AR POWER STATION, UNITS 1 AND 2 C0Ptl0NWEALTH EDISON COMPANY DOCKET NOS. 50-295 AND 50-304 I. BACKGROUND . -

( By letter dated June 17, 1986, CommonwealthEdisonCompany(theifcensee)

{ . submitted an updated set of relief requests for the inservice testing (IST) y program and a single relief request for the inservice inspe.ction (ISI) program

{

for the second t'en-year inspection interval at Zion Nuclear Power Station Units 1 & 2.

Attachment 2 to the submittal contains Revision 2 of the Zion ISI/IST Second Interval Program which consists of the single ISI relief request. The licensee requested relief from certain ISI hydrostatic pressure test requirements which had been detemined to be impractical to perfom at Zion Units 1 & 2 based on the requirements of the 1980 Edition through Winter V

1981 Addenda of Section XI of the ASME Code. This report provides an

[. evaluation of the licensee's request, supporting inforriation, and alternative examinations' or tests, as well as the staff's bases for grantinD or denying therequestpursuantto10CFR50.55a(g). The relief granted remains in effect for the second ten-year inspection interval unless revised or modified prior to the end of the interval. The relief request is evaluated below.

The relief request is reprinted on page 141e of Attachment 3 to the submittal.

l However, the first sentence on page 141e contains a typographical error such

t

' hat the lines OSWOO1-12" and OSW008-10" are omitted. .

II G608200380 8603CO PDP ADOCk 0Sd00095 O PDR

._. -.s,.- -

- - - - - - - - - - - ~ - ' ~ " ~ ~ ~ ~ ~ ~ -

g.-

c.,

{s  : .z- *

}

[ ,

II. EVALUATION OF RELIEF REQUEST

(.

F Class 3 Hydrostatic Pressure Test of Service Water Systems Code Examination Requirteents The pressure retaining buried components within the class 3 boundary are 1 subject to the hydrostatic test requirements of IWA-5244(a) during each I inspection interval. Specifically, the requirements of IWA-5244(a) are as lf follows:

Ib 4 In nonredundant systems where the buried components are isolatable by

{ means of valves, the visual examination VT-2 shall consist of a leakage -

? test that detemines the rate of pressure loss. Alternatively, the test may detemine the change in flow between the ends of the buried ft

components. The acceptable rate of pressuis loss or flow shall be

established by the owner.

L L

Code Relief Request

( _

h. ,

f Relief is requested free hydrostatic pressure tests in the buried piping sections of the service water systems on lines 0$W013-48", OSV014-48",

[{

OSW001-12", and OSW008-10".

l.

, Licensee Basis for Relief Hydrostatically testing the buried pipe portion using a pressure decay test as required by IWA-5244(a) is restricted due to the limiting design of tne valves used for test bounc' aries. The alternative test for buried components in IWA-5244(a) is a flow test. The use of a flow meter was attempted, however.

due to the pipe configurations, the required straight pipe length at the test

locations does not exist. As a result, the data obtained was inaccurate. In

(

i f ~

r

~

! . _ - - - 1 --- -

7 o .

t 6-f -3.- . .

~

additiontotherequiredtestmethodsofIWA-5244(a),anacousticalemission leak test was considered, but the limiting design configurations of the valves we'lld produce questionable and/or inaccurate results.

This relief has been previously submitted and approved for Zion's First

Interval ISI program.

i; Licensee Proposed Alternative Test

$ Testing for evidence of leakage shall be performed on these buried portions of lj the system listed above at their nominal operating conditions. The testing

!k shall consist of a verification that flow during operation is not impaired.

!k This is per IWA-5244(c).' -

p Staff Evaluation and Conclusions

The design of the valves cannot provide pressure isolation for the turfed components. The licensee attempted to measure the change of flow between the l[ ends of the components but obtained inaccurate data due to component design

!N limitations. The alternative test proposed by the licensee is the Code-

f.. required examination for nonisolatable buried components and will provide assurance of the integrity of the subject components. Furthermore, there are

existing independent surveillance test requirements of the service water systems that can provide an indication of system performance.

Based on the staff's evaluation and the licensee's discussion above, Code twquirements are impractical. It is further concluded that the alternative examination discussed above will provide necessary added assurance of the service water systems' structural reliability. Therefore, relief may be granted as requested.

l l

1 l

i: - - _ . - - _ __.___.-._._--.::_._---,

~ ~ T T:L _.__ . - - _ _ _ _ _ _