ML20199J634

Responds to NRC Re Violations Noted in Insp Rept 50-298/86-12.Corrective Actions:Switchgear Cabinets Welded to Embedded Channel Located Directly Beneath Cabinets

ML20199J634
Person / Time
Site:	Cooper
Issue date:	06/12/1986
From:	Pilant J NEBRASKA PUBLIC POWER DISTRICT
To:	Gagliardo J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20199J536	List: IR 05000298/1986012 ML20199J634
References
CNSS867445, NUDOCS 8607080385
Download: ML20199J634 (3)

Text

'

. 1' Nebraska Public Power District " ~ * "%$ bks $ffbst*** "

CNSS867445 ggggg June 12,1986 Jalism Mr. J. E. Gagliardo, Chief 'rs d.ame='- '

Reactor Projects Branch - - - - _

U.S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 1000 Arlington, TX 76011

Subject:

NPPD Response to Inspection Report 50-298/86-12

Dear Mr. Gagliardo:

This letter is written in response to your letter dated May 13, 1986, transmitting Inspection Report 50-298/86-12. Therein you indicated that one of our activities was in violation of NRC requirements.

Following is a statement of the violation and our response in accordance with 10CFR2.201.

STATEMENT OF VIOLATION Seismic Support of Emergency Switchgear Cabinets The Cooper Nuclear Station Technical Specification, Section 5.6, establishes that there is a seismic design required for Class I structures and equipment. The emergency diesel generators and attendant switchgear cabinets are Class I equipment. The General Electric instruction manual for the switchgear cabinets requires that the cabinets be anchored by welding or by bolting.

Contrary to the above, on March 18, 1986, it was found that the switchgear cabinets for the emergency diesel generators, which are Class I equipment, had not been anchored either by welding or bolting.

This is a Severity Level IV violation (Supplement I.D.)(298/86-12-01).

Reason for the Violation The statement of violation correctly describes the mounting anomalies discovered on the EG-1 and EG-2 switchgear cabinets for the Emergency Diesel Generators.

8607080385 860624 8 PDR ADOCK 0500 G

'h

T J. E. GIgliardo

June 12,1986 Page 2 The related original construction records were researched in an attempt to determine the cause for the Emergency Diesel Generator switchgear cabinets not being properly mounted.

Ilowever, the document search did not reveal any inconsistencies that would have resulted in the switchgear cabinet mounting anomaly.

Therefore, the District considers the mounting anomalies discovered on the Emergency Diesel Generator switchgear cabinets to be an isolated incident possibly caused by a construction oversight.

Corrective Steps Taken and Results Achieved When discovered, the mounting anomalies were immediately brought to the attention of CNS management. The problem was rigorously pursued to define the scope of the problem and to determine corrective steps required to return the cabinet mountings to full compliance with Technical Specifications.

After conversations with Cooper Station's Architect / Engineer (Burns and Roe) and review of the switchgear vendor recommendations, it was decided to v.sid the switchgear cabinets to the embedded channel located directly beneath the switchgear cabinets.

The welding was completed and conservative calculations l were performed that demonstrated these welds adequately met the seismic requirements.

The District has conducted a preliminary visual inspection of all floor mounted, safety-related switchgear at Cooper Station as plant conditions permitted. From the results of this inspection, the District has concluded that the EG-1 and EG-2 mounting anomaly was an isolated incident.

Corrective Steps Which Will Be. Taken to Avoid Further Violations A final thorough inspection of all floor mounted ,

l safety-related switchgear at Cooper Station will be l performed during the Fall 1986 outage.

l l

In addition, a complete review of construction reords l

related to safety-related, floor mounted switchgear will be

! performed to verify that the seismic criteria on this switchgear was initially addressed and documented.

l

r

. ".* J. E. G:glbrds

• ' Juns 12,1986 Page 3 Date When Full Compliance Will Be Acideved CNS is currently in full compliance.

Should you have any questions regarding this response, please contact me.

Sincerely, J. M. Pflant Technical Staff Manager Nuclear Power Group JMP:EMM:rs/CNS.401(COMM10)

P