ML16340C426
| ML16340C426 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 03/03/1982 |
| From: | Fair J, Herring K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE), Office of Nuclear Reactor Regulation |
| To: | Miraglia F Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML16340C425 | List: |
| References | |
| IEB-79-14, NUDOCS 8203240039 | |
| Download: ML16340C426 (18) | |
Text
~R Ately c>
"o
~
~y I
0O I
C
+~
~O
++*++
UNITEDSTATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 MAR 3 1'?
l MEMORANDUM FOR:
Frank Miraglia, Chief Licens in g B ranch No.
3 Division of Licensing, NRR FROM:
SUBJECT:
Kenneth S. Herring Systematic Evaluation Program Branch Divison of'Licensing, NRR John R. Fair Engineering.
8 Technical Support Branch Divison of Engineering and guality Assurance, NRR DIABLO CANYON SEISMIC VERIFICATION PROGRAM INSPECTIONS - FEBRUARY 22 - 26, 1982 As a part. of Region V's ongoing acti.vities to keep abreast of the current Diablo Canyon seismic verification program, we conducted unannounced inspections at the R. L. Cloud offices on February 22 and 23,
- 1982, and at the PGSE offices on February 24, 1982.
In addition, a walk-down of cer-tain aspects of the Diablo Canyon design was conducted at the plant on February 25 and 26, 1982, to gain a better understanding of issues identi-fied during the meetings at the R. L. Cloud and PGRE offices.
Our observa-tions and recommendations are discussed below.
R.
L. Cloud Ins ection 1)
Pi in and Su orts The piping analysis procedures, signed on 2/22/82, were reviewed.
The procedures were based on criteria presented in Section 8.2 of the Hosgri Report with additional criteria for overlap (NUREG/CR-1980),
decoupling (piping diameter ratio >4) and small diameter piping con-nected to large pipe (either (1) large pipe response in the span where the attachment point is located is greater than 20Hz or (2) the large line displacement
<1/16 inch).
The procedures did not include the load combi nation or stress allowable criteri a.
Two of the R. L. Cloud employees performing piping analyses were inter-viewed.
These employees were familiar with the piping analysis proced-ures and criteri.a.
Approved support evaluation procedures were not available at the time of the inspection.
The support frequency calculations were available but they had not been approved at the time of the inspection.
The re-sults of these calculations showed 19 of the 20 supports met the PG8E criteria for frequency as reported in the R.'L. Cloud progress report
-dated January 9, 1982.
Review of the calculations showed that snubber I
8203240039 820310 I
PDR ADOCK 05000275
- ,P,-., ',.'...'..'.,"
PDR,. ',...:..'ig
L g I
<<2 MAR 3
)ging flexibilities had not been included in the computations.
Cloud employees stated that these calculations had not been approved and the snubber flexibilities would be included in the final calcula-tions.
2)
E ui ment Calculation Review The only completed, checked and a'pprove'd calculation packages in any area were those for the Main Annunciator Cabinet located in the Cable Spreading Room and the Diesel Generator Fuel Oil Priming Tank.
Review of these calculations indicated the following.
a)
Main Annunciator Cabinet - In the calculation of the cabinet
- response,
- 1) 12 ga.
sheet metal side panels
( 25" x 85") were treated as simple beams without verification of the appropriate-ness of this assumption,
- 2) angle structural members were treated as simple beams without appropriate consideration of torsion, and
~ 3) the locations of the centroids of the angles were computed er-roneously.
The last error was found to be due to an error in the handbook used for calculations, however, it appeared 'that insuf-ficient consideration was given to the applicability 'of handbook formulas and the basic assumptions ingrained in handbook and simple beam formula formulations.
Dr. Cloud agreed that the calcuation should be redone.
He'urther indicated that this calculation, in addition to 3 others, had been performed by EDAC under a previous, since cancelled, subcontract.
These other calculations were found to be inappropriate by Cloud personnel and were'being redone.
The cabinet calculation was not checked in as much detail as the other 3 since it indicated that an EOI was to be generated.
Therefore, he felt that this was an isolated occurance of an approval of an erroneous calculation.
b)
Diesel Fuel Oil Priming Tank - No obvious errors were detected in the review of this calculation.
However, insufficient attention was given in the evaluation of the concrete anchor bolts used for the supports.
This appeared to be due to the low magnitude of the calculated seismic responses,
.however, we indicated to Cloud that these should be appropriately evaluated. in all future calculations.
Given that an error was found in 1 of the 2 completed equipment calcula-tions reviewed, it is recommended that the NRC staff review additional com-pleted equipment calculations.to determine whether or not this is an isolated case.
In addition, it was observed that procedures for perform-ing the analyses of all items in the Cloud verification effort have not yet been finalized by Cloud.
I~
3&
~IE I
1)
PGSE and Blume Civil 'En ineerin Related Calculations I
Several topics related to the calculations performed by the PGSE and Glume "Civil Engineering personnel were discussed.
These discussions are described below.
~
g g
a)
Containment Polar Crane - Discussions similar to those which took place on January 29, 1982, between Mr. Herring and PGLE and Blume personnel were reported.
Since that first discussion, PGEE had no new information relative to this issue and indicated that they intended to pursue it further.
(See Trip Report K. Herring to F. Miraglia, February 3, 1982.)
b)
Containment Internal Structure
Response
Above Elevation 140' The steam gener ator and pressurizer enclosures which extend about 40 feet above the operating deck (el.'140') were not modeled in the containment structural model.. Therefore, floor spectra at el. 140'ere used for the design of.piping and equipment attached above el. 140'nd coupled
-to these enclosures.
The effects of the enclosure flexibility are be-ing evaluated.
They indicated that affected items include Main Steam and Containment Spray piping, and the safety and power operated relief valves.
The analysis of the Containment Polar Crane in the parked and locked position (at the tops of the steam generator enclosures) is also affected since the flexibilityof these enclosures was not considered in Blume's analyses of this crane.
c)
Containment Pipeway - This steel frame structure, attached to the containment shell exterior, was initially assumed rigid. It appears that this assumption is not valid and the effects of its flexibility are being investigated.
PGSE indicated that items affected include the Main Steam, Main Feedwater and Auxiliary Feedwater
- piping, and the Main Steam Isolation Valves.
d)
Main Annunciator Cabinet '-
PGSE 'is analyzing the cabinet flexibility in light of Cloud's finding that it was not rigid as assumed initially.
They indicated that their prelimiary calculations were demonstrating that the cabinet was rigid.
However, the PGSE personnel performing the anal-yses were not aware of the connection details for the doors, internal member and cabinet supports to substantiate the validity of the assump-tions made in their analyses.
e)
Containment E>(haust Vent Structure Flexibility - Blume initially deter-mined (November, 19?0) that the exhaust vent had a natural frequency of 50 Hz and notified PGM of this fact.
In December,
- 1970, Blume determined that the 50 Hz was in error and that the frequency was 2 Hz.
However, they never notified PG&E of this change.
Hosgri evaluations done by PG&E relied upon the 50 Hz'requency and determined that the vent would remain elastic.
PG&E stated that with a 2 Hz natural fre-
- quency, recent evaluations indicate that modifications are required for the vent to remain elastic under the Hosgri criteria and they are
~
evaluating the feasibility of a non-linear analysis to demonstrate acceptability without modification.
Annulus Spectra Revisions - Three revisions to the containment annulus spectra have occurred since the initial discovery of the annulus problem.
The first accounted for appropriate orientation, and the second accounted for appropriate mass and stiffness distri-butions.
PG&E indicated that'he latest revision has been necessitiated by Blume discovering (in a recent internal Blume de-sign audit) tha't the upper vertical massess of the internal struc-ture in the initial Hosgri analyses inappropriately included such items as the Steam Generator, Reactor and Reactor Coolant Pumps.
In addition, the two masses of the internal structure were trans-posed in the recent evaluations.
Given these and previously identified problems relating to the analyses performed by Blume, PG&E stated that they were currently formulating a
program to be instituted'y Blume to check the adequacy of Blume's past analyses and to identify appropriate final analyses results.
We indicated that we concurred with the need for such a program.
2)
PG&E Pi in Desi n and Construction Recent R. L. Cloud progress reports have identified several as-built descrepancies during piping walk-downs. 'ne issue identified was valve operator orientation.
Correct measurements of valve operator orien-tations apparently were not made during the IE Bulletin 79-14 walk-downs.
PG&E currently plans to walk-down all piping to record correct valve orientations.
According to PG8E the majority of the as-built dimensional descrepancies identified by Cloud were errors in drafting and not in the analyses.
PG&E stated that the original piping drawings 'that were marked-up during the 'field as-built walk-downs were used by the piping analysts.
These drawings were then sent to the drafting department to develop the final isometrics.
These drawings were riot treated as record drawings and therefore, were not subject to stringent quality control procedures.
PG&E currently plans to upgrade the drawing controls on the piping i so-metric drawings and they also plan to perform a sample of 17 walk-downs to the IEB 79-14 criteria.
This effort will require further NRC review when PG&E completes the current evaluations on all open items.
0 3)
On oin PG5E Investi ations In addition to the work descri bed above, PGSE is in the process of instituting strong project management control of the'in-house seismic reverification effort.
Since PG8E has initiated and is initiating several additional internal programs to address the concerns identified by Cloud and themselves, it is recommended that the NRC staff meet with PG8E to discuss the adequacy of these programs and to address the open items identified to date..Special attention should be given to assuring that the resolution of problems is approached in an orderly fashion.
Site Visit Observations On our site visit, we inspected the containment exhaust vent, the steam gen-erator and pressurizer enclosures, and the Main Annunciator Cabinet.
Our observations are presented below.
1)
Containment Exhaust Vent From a visual inspection of this structure, it appeared obvious that the natural frequencies were substantially lower than the 50 Hz calculated initially by Blume, and used by PG8E in its Hosgri evaluation of this structure.
2')
Steam Generator and Pressurizer Enclosures From a visual inspection of these structures, the potential for further amplification of motion above el. 140'ppeared obvious, especially con-sidering the connection of the Polar Crane to the steam generator enclo-ures.
3)
Main Annunciator'anel From a visual inspection of this panel, it was observed that:
a)
The conception of this cabinet ingrained in the Cloud analyses was more representative of the physical configurati'on than that ingrained in recent PG&E evaluations.
b)
The analysis performed recently by PG8E contained several as-sumptions which were not representative of the physical situation.
c)
Several loose and missing bolts were obvious.
1 4
Based upon the above observations and the previous discussions of the problems in these areas, it appear s that many of these problems could have been avoided if analysts had been required to walkdown these structures.
(Eq paul!s Ieuppo Orfginal signe'd bY3.
Kenneth S, Herring Systematic Evaluation Program Branch Division of Licensing, NRR e'
~Is Nett<<.~<<'~
John R. Fair
~ Bigineering 8 Technical Support Bra ch Division of Engineering and guality Assurance, IE CC:
See next page OFFICE/
SURNAMEP DATEf MPS............
KHerring: b B/Qr/82 o ~ ~ ~
~
DE A....
JFair Sf82---
'QL...
glia 8f
'/82'RC FORM BIB (10-80) NRCM 0240 OFFICiAL RECORD COPY USQPO: 1981-335-9NI
t
'n"','
~ p, * %
~ w
~ ~,
t~
<<pw V
t ~ a[
w't I
il
~"p",i s
u tÃtl c 0
~ ".-
~ s 'l.'
4 ~
It" 8 j 0
S' r
~
~
s J
~ <
1 g'.
J K
h
Nr. Malcolm H. Furbush Vice President - General Counsel Pacific Gas h Electric Company P.O.
Box 7442 San Francisco, California 94120 DIABLO CANYON e
CC:
Philip A. Crane, Jr.,
Esq.
Pacific Gas 8 Electric Company P.O.
Box 7442 San Franc isco, Cal i fornia 94120 Janice E. Kerr, Esq.
California Public Utilities Commission 350 NcAllister Street San Francisco, California 94102 Nr. Frederick Eissler, President Scenic Shoreline Preservation Conference, Inc.
4623 Nore mesa Drive Santa 8'arbara, Cali fornia 93105 Ns. Elizabeth Apfelberg 1415 Cozadero San Luis Obispo, California 93401 Nr. Gordon A. Silver h1s.
Sandra A. Silver 1760 Alisal Street San Luis Obispo, California 93401 Harry N. Willis,.Esq.
Seymour 8
Willis'01 California Street, Suite 2100 San Francisco, California 94108 Nr. Richard Hubbard h1HB Technical Associates Suite K
1723 Hamilton Avenue San Jose, California 95125 Nr. John Narrs, h1anaging Editor San Luis Obispo County Telegram-Tribune 1321 Johnson Avenue P. 0.
Box 112 San Luis Obispo, California 93406
,A t 4
r
't
~
'I y
Mr. Malcolm H. Furbush I
cc:
Resident Inspector/Diablo Canyon NPS c/o U. S. Nuclear Regulatory Commission P. 0.
Box 369 Avila Beach, California 93424 Ms. Raye Fleming 1920 Mattie Road Shell Beach, Cali fornia 93440 Joel
- Reynolds, Esq.
John R. Phillips, Esq.
Center for Law in the Public Interest 10951 West Pico Boulevard Third Floor Los Angeles, California 90064 Paul C. Valentine, Esq.
321 Lytton Avenue Palo Alto,.California 94302 Mr. Byron S. Georgiov Legal Affairs Secretary Governor's Office State Capitol Sacramento, California 95814 Herbert H. Brown, Esq.
Hill, Christopher 8 Phillips, P.C.
1900 M Street, N.W.
Washington, D.C.
20036 Mr.'ichard E.
Bl ankenburg, Co-Publisher Mr. Wayne A. Soroyan, News-Reporter South County Publ> shing Company P. 0.
Box 460 Arroyo Grande, California 93420 Mr. James
- 0. Schuyler Vice President
- Nuclear Generation Department Pacific Gas 8 Electric Company P.O.
Box 7442 San Francisco, California 94120 Bruce Norton, Esq.
Suite 202 3216'orth 3rd Street
- Phoenix, Arizona 85012
n C
P
Mr. Malcolm H. Furbush Hr.
W. C. Gangl off Westinghous'e Electric Corporation P. 0.
Box 355 Pittsburgh, Pennsylvania 15230 David F. Fleischaker, Esq.
P. 0.
Box 1178 Oklahoma City, Oklahoma 73101 Arthur C. Gehr, Esq.
Snell 8 Wilmer 3100 Valley Center
- Phoenix, Arizona, 85073 Mr. Owen H. Davis, Director Federal Agency Relations Pacific Gas and Electric Company 1050 17th Street, N.W.
Suite 1180 Washington, D.c.
20036
4 E
l
~
4