ML16154A657
| ML16154A657 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 08/24/1994 |
| From: | Boger B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Hampton J DUKE POWER CO. |
| Shared Package | |
| ML16154A658 | List: |
| References | |
| EA-94-125, NUDOCS 9409120031 | |
| Download: ML16154A657 (18) | |
See also: IR 05000269/1994021
Text
ALUG
1'2'24
Docket Nos.:
50-269, 50-270, 50-287
License Nos.: DPR-38, DPR-47, DPR-55
EA 94-125
Duke Power Company
ATTN: Mr. J. W. Hampton
Vice President
Oconee Site
P. 0. Box 1439
Seneca, SC 29679
Gentlemen:
SUBJECT:
ENFORCEMENT CONFERENCE SUMMARY AND NOTICE OF VIOLATION
(NRC INSPECTION REPORT NOS. 50-269/94-21, 50-270/94-21, AND
50-287/94-21)
This letter refers to the enforcement conference held at our request on
August 4, 1994, at the Region II office in Atlanta, Georgia. This meeting
concerned activities authorized for your Oconee facility. The issues
.discussed
at this conference related to the inspection findings addressed in
Inspection Report 50-269,270,287/94-21 concerning the ability of your Keowee
Hydro-Electric Power facility to provide reliable emergency power to the
Oconee Nuclear Station. A list of attendees and a copy of your presentation
materials are enclosed.
Your presentation provided additional information and clarification with
respect to the apparent single failure violation and associated issues
identified in the subject Inspection Report. Our report indicated that
portions of the air system for Keowee Air Circuit Breakers (ACB) 1-4 were not
safety-related. This information was based on discussions with Oconee
personnel and was consistent with statements in Licensee Event Report
269/94-03 (dated July 25, 1994), which concerned a postulated single failure
that would result in the loss of the Oconee emergencypower-system. However,
during the enforcement conference, you stated that all portions of the subject
air system were designed, procured, built, and maintained to the same
standards; and therefore, your previous identification of certain parts of the
system as nonsafety-related was in error. Confirming that the air system in
question was not seismically qualified, you expressed your confidence that the
system could withstand a seismic event without loss of function. Addi
tionally, you asserted that even though a failure on an underground path ACB
could have caused a lockout of the overhead path, independence between the two
emergency power paths was maintained since the failure in question would not
result in the loss of the underground path. You further stated that credit
was taken for all portions of the air system, including those portions
previously identified and maintained as nonsafety-related, to replenish air to
the ACB reservoirs. Accordingly, you stated that no single-failure,
O
associated with the air system, would result in the loss of both Keowee
emergency power paths.
9409120031 940824
ADOCK 05000269
SDPDR
211
Duke Power Company
2
AUG 2 4 1994
Based on the information provided in your presentation, and a review of the
Oconee licensing basis, the NRC staff concluded that if the air supply system
had been maintained at appropriate safety-related standards to assure its
operability, one could assume that the air system was available when applying
single failure criteria to the emergency power system. However, the NRC does
not agree that all portions of the subject air system were maintained as
safety-related. Specifically, we attribute the excessive ACB check valve
leakage and the failure of the air system pressure regulating valve discussed
in Inspection Report 50-269,270,287/94-21, to inadequate preventive
maintenance. These deficiencies contributed to the lockout of the emergency
overhead path on June 14, 1994. Additionally, a lack of recognition as to the
importance of this system was demonstrated in that controlled drawings for the
air supply system did not exist, and controls for maintenance and operational
activities on this equipment were inadequate. These deficiencies resulted
from the failure to include all components of the air supply system for
ACBs 1-4 in your Quality Assurance Program. The failure to include these
components in the Quality Assurance Program and the failure to maintain and
control the air supply system to an extent consistent with its importance to
safety is a violation of the requirements of 10 CFR 50, Appendix B,
Criterion II, as specified in the enclosed Notice of Violation (Notice).
The NRC continues to be concerned that the staff at Oconee failed to
adequately identify and maintain all portions of the Keowee air system as
safety-related. The NRC is also concerned that your previous programmatic
efforts to identify the equipment that should be maintained as safety-related
did not correct this deficiency. You should take expeditious steps to ensure
that all the equipment at Keowee has the appropriate Quality Assurance
classification. During the enforcement conference, you committed to prepare
and have available by the end of September 1994, an aggressive schedule/plan
that addresses the open emergency power system issues for Oconee.
You are required to respond to this letter and should follow the instructions
specified in the enclosed Notice when preparing your response. In your
response you should document the specific actions taken and any additional
actions you plan to prevent recurrence... After-reviewing your response,
including your proposed corrective actions and the results of future
inspections, the NRC will determine whether further NRC enforcement action is
necessary to ensure compliance with NRC regulatory requirements.
In accordance with 10 CFR 2.790 of the NRC's "Rules of Practice," a copy of
this letter and its enclosures will be placed in the NRC Public Document Room.
The responses directed by this letter and the enclosed Notice are not subject
to the clearance procedures of the Office of Management and Budget as required
by the Paperwork Reduction Act of 1980, Pub. L. No.96-511.
AUG
L4 1994
Duke Power Company
3
Should you have any questions concerning this letter, please contact us.
Sincerely,
Bruce A. Boger, Acting Director
Divisiontof Reactor Projects
Enclosures:
1. List of Attendees
2. Licensee Presentation Materials
cc w/encls:
Mr. Steve Benesole
Compliance
Duke Power Company
P. 0. Box 1439
Seneca, SC 29679
OMr. A. V.
Carr, Esq.
Duke Power Company
422 South Church Street
Charlotte, NC 28242-0001
Mr. Robert P. Gruber
Executive Director
Public Staff - NCUC
P. 0. Box 29520
Raleigh, NC 27626-0520
Mr. Robert B. Borsum
Babcock and Wilcox Company
Nuclear Power Generation Division
1700 Rockville Pike, Suite 525
Rockville, MD 20852
Mr. J. Michael McGarry, III, Esq.
Winston and Strawn
1400 L Street, NW
Washington, D. C. 20005
Office of Intergovernmental Relations
116 West Jones Street
Raleigh, NC 27603
(cc w/encls cont'd - See page 4)
Duke Power Company
4
2 4 1994
(cc w/encls cont'd)
Mr. Max Batavia, Chief
Bureau of Radiological Health
South Carolina Department of Health
and Environmental Control
2600 Bull Street
Columbia, SC 29201
Manager, LIS
NUS Corporation
2650 McCormick Drive
Clearwater, FL 34619-1035
Mr. G. A. Copp
Licensing - ECO50
Duke Power Company
P. 0. Box 1006
Charlotte, NC 28201-1006
Ms. Karen E. Long
Assistant Attorney General
N. C. Department of Justice
P. 0. Box 629
Raleigh, NC 27602
bcc w/encls:
(See page 5)
Duke Power Company
5
AUG24 1994
bcc w/encls:
L. A. Wiens, NRR
R. Carroll, RH
M. V. Sinkule, RH
Document Control Desk
NRC Resident Inspector
U.S. Nuclear Regulatory Commission
Route 2, Box 610
Seneca, SC 29672
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DOCUMENT NME: P:\\ONSMTNQ-1
ENCLOSURE 1
LIST OF ATTENDEES
U. S. Nuclear Requlatory Commission
L. Reyes, Deputy Regional Administrator, Region II (RH)
B. Mallett, Acting Deputy Director, Division of Reactor Safety
(DRS), RII
H. Berkow, Director, Project Directorate 11-3, Office of Nuclear
Reactor Regulation (NRR)
P. Skinner, Acting Chief, Division of Reactor Projects (DRP)
Branch 3, RH
T. Peebles, Chief, Operations Branch, DRS, RH
B. Bonser, Acting Chief, Reactor Projects Section 3A, DRP, RH
P. Humphrey, Acting Project Engineer, Section 3A, DRP, RH
L. Wiens, Project Manager, Project Directorate 11-3, NRR
P. Harmon, Senior Resident Inspector, Oconee, DRP, RH
L. Keller, Resident Inspector, Oconee, DRP, RII
F. Burrows, Electrical Engineering Branch, NRR
L. Watson, Enforcement Specialist, Enforcement and Investigation
Coordination Staff, RH
C. Evans, Regional Counsel, RH
K. Clark, Public Affairs Officer, RH
Duke Power Company
J. Hampton, Vice President, Oconee Nuclear Station (ONS)
J. Davis, Engineering Manager, ONS
B. Dolan, Safety Assurance Manager, ONS
C. Little, Electrical Engineering, ONS
J. Rowell, System Engineer, ONS
G. Savage, Public Affairs, Duke Power Company
M. Bailey, Regulatory Compliance, ONS
H. Grant, Electrical Engineer, ONS
R. Severance, System Engineer, ONS
ENCLOSURE 2
LICENSEE PRESENTATION MATERIALS
AGENDA
BACKGROUND
SEQUENCE OF EVENTS
LICENSING BASIS
ACTIONS BEING TAKEN
SAFETY SIGNIFICANCE
Keowee Emergency
Power Paths To Oconee
OCONEE
OVERHEAD
Emergency
Power Path
Keowee
Main Step-Up
Transformer
OCONEE
CT4
UNDERGROUND
Emergency
Power Path
ACB2
ACB4
ACB3
ACB1
2
KEOWEE
ARC CHUTE-
SPLITTER-
-
COOLER
CONTACT
FINGER
UPPER
AR TTERMINAL
MOVING
CONTACT
LOWER
TERMINAL
0 0
BLAST TUBE-
OPERATING
ROD
BLAST VALVE
SHAFT CAM
MAGNET
VALVE
PI STO0N---
PNEUMATICL
M ECHAN IS M-- -
MAGNET
VALVE
RESERVOIR
INCOMING AIR .CHECK
VALVE
SUPPLY
WIRING
CHANNEL
FIG.
2
Breaker Side View Showing Comoressed Air Flow
Photo 326022
33-680-C2
6
DIAGRAMMATIC LAYOUT
OF KEOWEE GENERATOR ACB AIR SYSTEM
UNIT I ACD
UNIT 2 ACB
AIR COMPRESSOR
AIR COMPRESSOR
AND ACCUMULATOR
AND ACCUMULATOR
o
0
ACB1
ACB3
ACB4
ACB2
Ll
LEGEND:
Z = Manual Valve
(
=Regulator
z
=Low Pressure Protection Isolation Valve
SEQUENCE OF EVENTS
JUNE 14, 1994
PERFORMING ANNUAL PREVENTATIVE
MAINTENANCE ON ACB 1
DURING SEQUENCE OF CHARGING ACB 1 RESERVOIR,
COMBINATION OF REGULATOR STICKING AND
LEAKS IN ACB 3 CAUSED ACB 3 RESERVOIR
.
PRESSURE TO DROP TO 118 PSI
TRANSFORMER LOCKOUT INITIATED
NOTE:
1.
Purpose of lock-out is to protect Keowee
Generators and is part of original design
2.
Engineers and technicians aware of the features
3.
PM procedures require calibration of alarms and
lock-out pressure switches
JUNE 14 (CONT)
OPENED TIE VALVE TO UNIT 2 AIR HEADER
RESTORING AIR PRESSURE TO UNIT 1
ENTERED LCO FOR OVERHEAD UNAVAILABILITY
OPERABILITY CHECKS MADE OF BOTH UNITS TO
BOTH PATHS
INITIATED PROBLEM IDENTIFICATION PROCESS ON
EVENTS
EXITED LCO
JUNE 15
PERFORMED PM ON ACB 3
JUNE 16
INSPECTED AND REPAIRED UNIT 1 AIR COMPRESSOR
AIR REGULATOR
TESTED ACB 3 AIR SYSTEM USING IMPROVED TEST
KEOWEE CONSIDERED OPERABLE
JUNE 20
PERFORMED PM ON ACB 4
PERFORMED IMPROVED AIR TEST ON ACBs 1 AND 4
JUNE 21
INVESTIGATED BASIS OF AIR LEAKAGE ACCEPTANCE
CRITERIA
PREPARATION MADE FOR REPAIRING ACB 4
JUNE 22
REPAIRED ACB 4 AND TESTED SYSTEM FOR AIR
LEAKAGE
PERFORMED PM ON ACB 2
ENTERED LCO DUE TO UNCERTAINTY IN DESIGN
ASSUMPTIONS
JUNE 23
INSTALLED TEMPORARY MODIFICATION TO REMOVE
LOCKOUT FEATURE ON LOW AIR PRESSURE IN ANY
ACB
LICENSING BASIS
KEOWEE DESIGNED AND BUILT TO RELIABLE
HYDRO STANDARDS WITH ADDED FEATURES TO
PROVIDE ALTERNATE PATHS OF POWER AND
AUTOMATIC STARTUP FEATURES
OCONEE DESIGN BASED ON "THE LARGE NUMBER OF
POWER SOURCES, THE RELATIVELY LARGE
CAPACITY OF THESE SOURCES, AND THE HIGH
RELIABILITY OF THE HYDRO UNITS."
AIR SUPPLY SYSTEM WAS CONSIDERED A PART OF
THE ACB'S AND AVAILABLE TO MAINTAIN NORMAL
OPERATING PRESSURE IN THE ACB RESERVOIRS
ACB AIR SUPPLY SYSTEM SEISMICALLY ADEQUATE
ACTION BEING TAKEN
ADDITIONAL RESOURCES BEING COMMITTED TO
EXPEDITE COMPLETION OF OUR PLANS ASSOCIATED
WITH EMERGENCY POWER
AGGRESSIVE SCHEDULE BEING PREPARED AND
AVAILABLE ON SEPTEMBER 15, 1994
SAFETY SIGNIFICANCE
KEOWEE EMERGENCY START NOT AFFECTED
UNDERGROUND ALWAYS AVAILABLE
CT 5 FROM LEE/CENTRAL AVAILABLE
SSF AVAILABLE
TWO AIR PRESSURE SYSTEMS AVAILABLE
PROBABILITY OF AN EVENT RESULTING IN LOSS OF
ALL POWER TO OCONEE IS EXTREMELY LOW