ML17083A993

Draft Commission Paper Requesting Approval of AO Determination Re Seismic Design Errors at Facility.Proposed Fr Notice Encl

ML17083A993
Person / Time
Site:	Diablo Canyon
Issue date:	02/05/1982
From:	Dircks W NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO)
To:
Shared Package
ML17083A991	List: ML17083A990 ML17083A992 ML17083A993
References
NUDOCS 8203040037
Download: ML17083A993 (20)

Text

for:

From:

The Commissioners William J. Dircks Executive Director for Operations

Purpose:

Di scussion:

ABNORMAL OCCURRENCE RECOMMEHDATIOH - SEISMIC DESIGN ERRORS AT DIABLO CANYON NUCLEAR POWER PLANT t

Approval of an abnormal occurrence determination.

Enclosed is a draft Federal Regi,ster notice in regard to the seismic design errors at.the Diablo Canyon Nuclear Power Plant with the subsequent suspension of the fuel load and low-power operating license of Unit 1 on November 19, 1981.

'I This item is proposed for reporting based on one of the general criteria of the Abnormal Occurrence Policy Statement; i.e., major deficiencies in design, construction, use of, or management controls for licensed facilities or material can be considered an abnormal occurrence.

CONTACT:

J.

Crooks/P.

Bobe 492-4425/492-4426 8203040037 S2021h

,, PDR ADOCK 05000275

'; -P, PDR

Recommendation:

That the Commission:

Approve the subject proposed abnormal occurrence together with its associated Federal Register Notice and Z.,

Note that following approval, the Office of Congressional Affairs will notify the appropriate Congressional Committees of the intent to publish the Federal Register Notice.

Scheduling:

While no specific circumstances require Commission Action by a particular date, it is desirable to disseminate abnormal occurrence information to the public as soon as possible.

It is expected that Commission action within two weeks of receipt of this draft proposal would permit publication in the Federal Register about 10 days later.

Enclosure:

Oraft Federal Register Notice William J.

Dircks Executive Oirector for Operations

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[?590-013 NUCLEAR REGULATORY COHHI SSION SEISl1IC DESIGN ERRORS AT DIABLO and Electric (PGAE} submitted letters to the NRC stating that certain draw'ings

("diagrams")

used in the seismic design in the Diablo Canyon Unit 1 containment annulus area were in error.

The "diagrams" used were

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ABNORHAL OCCURPENCE

~ V CANYON NUCLEAR POHER PLANT

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~ 34 Section 208 of the Energy Reorganization Act of 1974, as

amended, requires e

the NRC to disseminate information on abnormal occurrences (i.e., unscheduled incidents or events which the Commission determines are significant from the standpoint of public health and safety}.

The following incident was 'determined to be an abnormal occurrence using the criteria published in the Federal o

> Register on February 24, 1977 (42 FR 10950).

One of the general criteria C

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notes that major deficiencies in design, construction, use 'of, or management 4e

~~ controls for licensed facilities or material can be considered an abnormal occurrence.

The following description of the incident also contains the C'

remedial actions taken to date.

Date and Place -

On September 28, 1981 and September 30, 1981, Pacific Gas applicable to Diablo Canyon Unit 2, but were identified for use in.the Unit 1 seismic design.

Subsequent investigation into this issue revealed additional design errors.

This resulted in suspension of the Diablo Canyon Unit 1 fuel load and low-power operating license.

(Unit 2 was

,still under construction and had not yet received an operating license).

Diablo Canyon Units 1 and 2 utilize pressurized water reactors and are located in San Luis Obispo County, California.

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'L >5SO-0>j Nature and Probable Consequences On September 21,

1981, an engineer employed by PGEE in the hanger design group, was performing work for Diyblo Canyon Unit 2 in response to NRC IE Bulletin NO.

79-14 ("Seismic Analysis for As-Built Safety-Related Piping Systems" ).

This work involved the use of "diagrams" of the containment building annulus area.

The engineer became suspicious that the supposed Unit 2 "diagrams" did not accurately represent Unit 2 structural configuration.

On September 21-22,

1981, he continue'd to investigate this apparent dis-crepancy and brought it to the attention of his immediate supervisor.

On September 24, the responsible Senior Civil Engineer had been informed of the apparent discrepancy.

On September 25, second level PGRE management were notified and they in turn contacted their seismic desi gn contractor, URS/John A. Blume and Associates (URS/Blume).

VRS/Blume confirmed that the wrong "diagrams" had been used.

On September 26, PGSE management continued to evaluate the problem.

On September 27, the Plant Superintendent notified the NRC Senior Resident Inspector that a problem did indeed exist.

NRC investi gation into the situation disclosed the following:

( 1)

The "diagrams" were developed at PGfiE and apparently given to URS/Blume on March 8, 1977 for their use in the development of vertical seismic response spectra for the Unit 1 and Unit 2 containment building annulus areas.

(2)

URS/Blume, when given the "diagrams,"

knew the "diagrams" were applicable to Unit 2.

However, they were not aware that the Unit 1 and Unit 2 con-tainment annulus areas are mirror images.

Therefore, during the

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30-01 3 development of the associated seismic response

spectra, URS/Blume assumed that both Unit 1 and Unit 2 containment buildings were of the same configuration.

(3)

PGSE, upon receipt of the seismic response spectra in Hay 1977 and July 1977, developed by URS/Blume, assumed the spectra and associated containment annulus frame ori entation "diagrams" were for the Unit 1

containment since it was identified as such by URS/Blume.

In actuality, the containment annulus frame orientation "diagrams" represented the Unit 2 containment.

PGSE, in turn, performed erroneously used Unit 1 containment annulus frame orientation subsequent design calculations for Unit 2 and, thus in turn, c4 "diagrams" for the development of Unit 2 design requirements.

~f Upon confirmation that wrong "diagrams" Here used in the development o

of Unit 1 design requirements, PGSE reanalyzed the design requirements go using the. appropriate containment annulus frame orientation "diagrams" and 9

determined that, as a result of the error, modifications were required to C'

C.~j $ be made on 31 Unit 1 pipe.su orts.

These modifications involved such g

~ actions as adding snubbers, changing the snubber size, adding braces, 1

p~>> replacing structural

members, and stiffening base plates.

u 'O'ubsequent investigations by the

HRC, and design reviews by PGSE

<~ and their consultant have identified a significant number of additional h

i,J i~ i'design concerns.

These include:

failure to use the latest revision of the vertical response spectra in design of conduit and cable tray supports; incorrect weight distribution used to determine the containment annulus vertical seismic response s

e tral curves; erroneous spectra used to

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+590-01]

complete safety injection piping problem; and two small bore piping snubbers required by seismic analyses were not designed or installed.

The design reviews are continuing at this time.

Cause or Causes

- The problem related to the use of the wrong "diagrams" appears to have been caused by the informal manner in which certain data were developed by PGKE and transmitted to URS/Blume and the lack of independent review of these data within PGSE prior to submittal to URS/Blume.

Identification of the additional design errors indicates a more general failing in the licensee's design quality controls for service type contractors.

Actions Taken to Prevent Recurrence Licensee - At the end of September 1981, the licensee verbally requested the services of a consultant, R.

L. Cloud Associates, Inc.

(R. L. Cloud) to I

conduct a seismic design review to determine if other errors had been made in the seismic design of Diablo Canyon Unit 1.

This request was subsequently formalized by the licensee with the issuance of a contract to R.

L. Cloud.

HRC - In October 1981, the HRC conducted a special inspection at the PGSE URS/Blume offices in San Francisco, California to evaluate the quality assurance programs and other management control systems in effect at PGEE and at URS/Blume during the period from 1970 to present; the extent P

to which these quality assurance programs and management control systems were implemented as they relate to the development, transmittal, and use of safety-related design information; and, how the identified seismic problems involving the Diablo Canyon containment building annulus areas

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/590-01]

were caused and subsequently discovered.

The results of this special i nspection indicated, among other things, that required quality controls were not imposed upon PGGE's safety-related, service type contractors

ntil late 1977 or. early 1978; and, many of the work activities perfori)od by PGGE with regard to the URS/Blume contract were performed n

in an informal manner.

On November 19,

1981, an order was issued by the Commission which suspended License No.

DPR-76.

DPR-76 had been issued on September 22,

1981, and had authorized fuel loading and the conduct of tests at up to five percent of rated power at Diablo Canyon Unit 1.

This order, in conjunction with a letter from the HRC Office of Nuclear Reactor Regulation, defined what would be required from PG8E prior to start of fuel loading and prior to power operation above five percent power at Diablo Canyon Unit 1.

These requirements included the completion of an independent design verification program for seismic related service contracts.

In conjunction with this the licensee was directed to submit a detailed program plan for conducting the design verification and to supply information that demonstrates the independence of the companies proposed to conduct the independent verfication.

The licensee has submitted a program plan and information regarding the independence. of the contractor (R.

L. Cloud) selected by the licensee.

Prior to an HRC decision on the acceptability of the program plan and the designated independent contractor an additional issue arose. 'his issue involves the licensee's review and comment on draft editions of the independent consultant's report prior to the submittal of the report to the

NRC, and statements made by licensee representatives to the NRC which led the HRC to believe that the licensee had not seen drafts of I

the report.

The issue is currently under HRC investigation.

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0 590-013 Future reports on the findings of the investigation, acceptability of the program plan and the independent contractor will be made, as appropriate, i.n..the quarterly Report to Congress on Abnormal Occurrences (NUREG-0090 Series).

Dated at l<ashington, D.C. this day of 1982.

Samuel J. Chilk Secretary of the Commission

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PLEASE RBVK< 'THE>DUE~ DATEI'bREDE'ATELY If the aX'P date does not allow adequate time to respond to this ticket, you may request a revised due date.

The request must include a valid justification and be submitted through your correspondence coordinator to the NRR mail room.

Such'.

request for green tickets must be made withi 3 days after assignment.

Requests for re-vision of yellow ticket due dates may be made, with justification, through the weekly WITS update.

The revised due date, if approved by PPAS, will be used to track division correspondenci completion schedules.

All green tickets are due to Mr. Case/via ERR mail room two days before the EDO-stated due date.

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F IDIOM CarlyIe M.chelson DATE'F DOCUMENT REPORT:

OTHER DATE RECEIVED NO"'2/8/82HRR-82-057 TO ORIG.I CCI OTHER:

H. Benton CLASS IF~

DESCRIPTION IMssss Be IAscsessAed)

POST OFFICE REG. NOI ACTION NECE'SSARY Q

NO ACTION NECESSARY Q FILE COOEI REFERRED TO CONCURRENCE COMMENT DATE P

DATE ANSWERED, 0

BYs2 RECEIVED BY DATE proposed abnonaal occurence-seismic design errors at Diablo

-Gayea Nuclear POTPIer Plant f ~

ENCLOSURES;1 Bisenhut cc' benton 2.

1lanauer 4.

Volleyer 6.

Check REMARKS U. S NUCLEAR REGULATORY COMMISSION MAILCONTROL FORM FORM NRC326 11 751

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