ML20211P890

Forwards Engineering Evaluation Rept AEOD/E608, Reexam of Water Hammer Occurrences, in Response to Action Item 2 in EDO 860204 Memo

ML20211P890
Person / Time
Issue date:	07/14/1986
From:	Hebdon F NRC OFFICE FOR ANALYSIS & EVALUATION OF OPERATIONAL DATA (AEOD)
To:	Speis T Office of Nuclear Reactor Regulation
Shared Package
ML20211P894	List: ML20211P890 ML20211P897 ML20211P904
References
REF-GTECI-A-01, REF-GTECI-PI, TASK-A-01, TASK-A-1, TASK-OR AEOD-E608, NUDOCS 8607230409
Download: ML20211P890 (2)

Text

July 14, 1986 AE0D/E608

.o MEMORANDUM FOR: Themis P. Speis, Director

. DISTRIBUTION Division of Safety Review and Oversight CPOR.

Office of Nuclear Reactor Regulation AE00 SF AE0D CF FROM:

Frederick J. Hebdon, Deputy Director ROAB CF Office for Analysis and Evaluation Eleeds of Operational Data SRubin KBlack

SUBJECT:

RE-EXAMINATION 0F WATER HAMMER OCCURRENCES FHebdon CHeltemes Enclosed is AEOD engineering evaluation report (AE0D/E608) concerning a review of water hammer events which have occurred since the resolution of Unresolved Safety Issue (USI) A-1, " Water Hammer." The study was initiated by AE0D to support NRR's response to staff action Item No. 2 enclosed with the February 4, 1986 ED0 memorandum:~ " Staff Actions Resulting from the Investigation of the November 21, 1985 San Onofre Nuclear Generating Station, Unit 1 Event (NUREG_1190)."

The study was primarily concerned with identifying and evaluating water hammer events caused by check valve leakage or failure. The study found that the underlying causes and general nature of the water hammer events which have occurred over the past five years do not appear to indicate any new generic concern not already identified and examined by the staff. Check valves were involved in only 2 of the 40 water hammer events evaluated.

Furthermore, check valves were found to have been specifically cited as contributing to only five of the almost 200 water hammer events evaluated since 1969.

Therefore, the study concludes that check valve leakage or failure was not and is not a significant generic cause of water hammer.

The information, analysis and evaluation contained in the enclosed report would appear to be useful for supporting your assessment of this issue.

In this regard, we understand that your proposed response for action Item No. 2 incorporates elements of the enclosed AE0D report.

If you or your staff have any question concerning the enclosed engineering evaluation report, please contact Eric Leeds of my staff on extension 24445.

IM Frederick J. Hebdon, Deputy Director Office for Analysis and Evaleation of Operational Data

Enclosure:

yj As Stated cc w/ enclosure:

A. W. Serkiz, NRR V. Hodge, IE g72go9860714 NEXD W. Minners, NRR D. Humenansky, OCM J. Sniezek, DEDROGR

' *See previous concurrence OFC :ROAB

C:ROAB

DD:AEOD

D:

_____:_____.______:____________:_____aj____:.

' NAME :Eleeds

SDRubin

FJHebdon

CJ temes DATE :6/27/86*

6/27/86*

7/9/86

7/686 0FFICIAL RECORD COPY

MEMORANDUM FOR: Themis P. Speis, Director DISTRIBUTION Division of Safety Review and Oversight PDR Office of Nuclear Reactor Regulation AEOD SF AEOD CF FROM:

Frederick J. Hebdon, Deputy Director R0AB CF Office for Analysis and Evaluation ELeeds of Operational Data SRubin KBlack

SUBJECT:

RE-EXAMINATION OF WATER HAMMER OCCURR.CES FHebdon CHeltemes Enclosed is AEOD engineering evaluation report (AF0D/E

) concerning a review of water hammer events which have occurred sincejthe resolution of Unresolved Safety Issue (USI) A-1, " Water Hammer." The stddy was initiated by AE0D to support NRR's response to staff action Item Np'. 2 enclosed with the February 4, 1986 ED0 memorandum:

" Staff Actions Resulti,ng from the Investigation of the November 21, 1985 San Onofre Nuclear Generating Station, Unit 1 Event (NUREG-1190)."

The study was primarily concerned with,fdentifying and evaluating water hammer events caused by check valve leakage or failure. The study found that the underlying causes and general nature of the water hammer events which have j

occurred over the past five years do not appear to indicate any new generic concern not already ioentified and/ examined by the staff. Check valves were involved in only 2 of the 40 water hammer events evaluated.

Furthermore, check valves were found to have,been specifically cited as contributing to only.five of the almost 200 water hammer events evaluated since 1969.

Therefore, the study concludes' that check valve leakage or failure was not and is not a significant gene'ric cause of water hammer.

/

The information, analysis a'nd evaluation contained in the enclosed report would appear to be useful/for supporting your assessment of this issue.

In this regard, we understand that your proposed response to ED0 action Item No. 2 incorporates elements of the enclosed AE0D report.

If you or your staff.have any question concerning the enclosed engineering evaluation report, please contact Eric Leeds of my staff on extension 24445.

i Frederick J. Hebdon, Deputy Director Office for Analysis and Evaluation of Operational Data

Enclosure:

l As Stated cc w/ enclosure A. W. Serkiz, NRR V. Hodge, IE W. Minners, NRR D. Humenansky, OCM J. Sniezek, DEDR0GR

/

N _ __ _

l OFC

____AE0D D:AE0D

_ _ _ _ _ : _ _R_O_A_B_.IJ._ _ : _ C_: RO_AB_ _ _ _ _ ::

DD: ________:____________:____________:____________:___________

jNAME : ELee SDRubin FJHebdon CJHel temes

, _ _ _ _ _ :... _ _ 'd s (p/27/86

/ /86

/ /86 l DATE :f /J 7 /86 :

l oft 1CIAL RECORD COPY

_..