ML17059C112
| ML17059C112 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 06/26/1998 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML17059C110 | List: |
| References | |
| 50-220-98-11, NUDOCS 9807070062 | |
| Download: ML17059C112 (20) | |
See also: IR 05000220/1998011
Text
U.S. NUCLEAR REGULATORY COMMISSION
REGION I
Docket/Report No.:
50-220/98 5Q
License No.:
Licensee:
Niagara Mohawk Power Corporation
P. O. Box 63
Lycomiin, NY 13093
Facility:
Nine Mile Point, Unit 1
Location:
Scriba, New York
Dates:
April4- June 9, 1998
Inspectors:
Approved by:
B. S. Norris, Senior Resident Inspector
T. A. Beltz, Resident Inspector
R. A. Skokowski, Resident Inspector
W. A. Cook, Project Engineer
Lawrence T. Doerflein, Chief
Projects Branch
1
Division of Reactor Projects
9807070062
980626
ADOCK 05000220
8
EXECUTIVE SUMMARY
Nine Mile Point Unit 1
50-220/98-1
1
April 4 - June 9, 1998
This NRC special inspection report includes the results of independent inspection and a
review of licensee activities in response to the failure to properly restore
a safety system to
,an operable condition and the resultant degradation of primary containment integrity for
3.5 days.
PLANT OPERATIONS
A Unit 1 reactor operator failed to follow the operating procedure for restoration of the
containment spray system to its standby configuration resulting in the system being in a
degraded condition for 3.5 days.
This was a violation of Technical Specification 6.8.1,
involving the failure to implement procedures,
as written.
(VIO 50-220/98-11-01)
Between April 7 and 11, over sixty control panel walkdowns were unsuccessful
in
identifying this containment spray system mis-positioned valve.
This was a significant
operations staff oversight and indicative of a lack of attentiveness
to safety system
configuration.
In contrast, the in-plant operator's identification of the breaker open/closed
indicating lights deficiency demonstrated
good attention to detail, proper awareness
of
plant conditions, and prompt and appropriate response to a deficient condition.
The licensee's immediate action to conduct control panel system line-up verifications
without referring to the system operating procedures was a poorly founded decision based
upon the control room operators not having identified the flow control valve out-of-position
for 3.5 days by relying on unaided memory of proper systems'onfiguration.
The identification of FCV 80-118 as a primary containment isolation valve by the systems
engineer was good, but the oversight by the operations staff of this valve's primary
containment isolation function reflects poorly on their systems knowledge and sensitivity
to containment integrity monitoring. The failure to maintain primary containment integrity
for 3.5 days was a violation of the Unit 1 Technical Specification 3.3.0.
{VIO50-220/98-
1 1-02)
TABLE OF CONTENTS
EXECUTIVE SUMMARY
TABLE OF CONTENTS
~
III
I. OPERATIONS........... ~........ ~... ~..................
~ ~...
1
01
Conduct of Operations ....
'
~
1
01.1
Failure to Follow the Operating Procedure Resulted in the Unit 1
Containment Spray System Being Degraded
..
1
01.2
FCV 80-118 Primary Containment Isolation Function ...........
3
08
Miscellaneous Operations Issues ....................
~
~
~
~
~
~ 5
08.1
(Closed)
LER 50-220/98-04:
Containment Isolation Valve Left
Open in Violation of Technical Specifications Due to Personnel
Error 5
V. MANAGEMENTMEETINGS...
X1
Exit Meeting Summary
.
~ ..
~
~
~
~
5"
~
~
~
~
~
~
~ 5
ATTACHMENT
Attachment
1 - Partial List of NMPC Persons Contacted
- Inspection Procedures
Used
- Items Opened, Closed, and Updated
- List of Acronyms Used
REPORT DETAILS
Nine Mile Point Unit 1
50-220/98-1 1
April 4 - June 9, 1998
I. OPERATIONS
01
Conduct of Operations
01.1
Failure to Follow the 0 eratin
Procedure
Resulted in the Unit 1 Containment
S
ra
S stem Bein
De raded
a.
Ins ection Sco
e
71707'n
April 7, 1998, while operating at full power, the Unit 1 reactor operator (RO)
responsible for restoring the containment spray (CS) system to the standby
condition failed to close the remote manual test return valve.
This adverse
condition was not recognized for 3.5 days, even though there were over 60 control
room panel walkdowns conducted by three different operating shift crews.
The inspectors discussed the event with the Unit 1 Operations Manager and the
General Supervisor of Operations
(GSO) and conducted independent interviews with
the responsible
RO and several other ROs and senior reactor operators
(SROs) who
performed the panel walkdowns before the open valve was identified.
In addition,
the inspectors observed management
meetings related to the event, including a
Station Operations Review Committee (SORC) meeting, and reviewed the
associated
operating procedures,
the Unit 1 Technical Specifications (TSs) and
Updated Final Safety 'Analysis Report (UFSAR). The inspectors also conducted
an
independent walkdown of the control room panels to verify that all safety systems
were aligned properly.
b..Observations
and Findin s
On April 7, operators were using the ¹121 CS pump to lower water level in the
torus per NMPC Oper'ating Procedure N1-OP-14, "Containment Spray System."
As
required by the TSs, the appropriate Limiting Condition for Operations (LCOs) were
entered.
After the desired torus level was achieved, the Assistant Station Shift
Supervisor (ASSS) directed the operators to restore the containment spray system
to the standby condition, using Section "G" of N1-OP-14.
The Chief Shift Operator
(CSO) performed the portions of the procedure
in the control room and directed an
in-plant operator to perform those steps outside of the control room.
The inspectors
determined that the CSO was using a controlled'working copy of the procedure and
was using the "place keeping" method, of checking off the steps as they were
1 Topical headings such as 01, MS, etc., are used in accordance with the NRC standardized reactor inspection report outline.
Individual reports are not expected to address
all outline topics.
The NRC inspection manual procedure or temporary instruction
ITI) that was used as inspection guidance is listed for each applicable report section.
completed.
The day-shift crew that started the restoration completed steps G.1.1
through G.2.12.
This crew was then relieved by the night-shift crew.
The night-
shift CSO was tasked with completing the remainder of the restoration; specifically,
steps G.2.13 through G.2.19. At 8:23 pm, the CSO reported that the containment
system restoration was complete, and that the ASSS could exit the applicable TS
LCOs.
However, as discovered on April 11, the CSO failed to perform step G.2.18
which states,
in part, to verify closed valve 80-118, the containment spray test
return to torus flow control valve (FCV). The failure to properly complete step
G.2.18 of procedure N1-OP-14 is a violation of Unit 1 TS, Section 6.8.1, which
requires procedures to be implemented, as written.
(VIO 50-220/98-11-01)
The inspector. determined that for the remainder of the April 7 night shift, and
subsequent
shifts until April 11, the CSO or extra control room operator (CRE)
performed panel walkdowns every two hours, as prescribed by the Operations
Manager.
This expectation
is contained in the Nine Mile Point 0 erations Manual
(common to both units) and the Unit I Reference Manual (predecessor
to the
Operations Manual).
However, the inspector noted that there is no specific
guidance for the panel walkdowns, such as systems'alve
position checklists, to
ensure the standby configuration of each safety system.
Additionally, procedure
N1-ODP-OPS-0101, "Shift Turnover and Brief," requires each oncoming RO and
SRO to walkdown the control room panels prior to assuming the shift. This
requirement, likewise, does not provide specific guidance as to what the turnover
panel walkdown should accomplish.
As a consequence,
over 60 control room panel
walkdowns.were unsuccessful
in identifying the mispositioned FCV 80-118,
At approximately 8:30 am, on April 11, an in-plant operator noted that both the
open (red) and closed (green) indicating lights on the local panel for the FCV 80-118
motor operator breaker were not lit. After replacing the light bulbs, the operator
recognized that FCV 80-118 should be closed and immediately notified the control
room. The SSS directed that the valve be closed and the TS LCOs properly exited
(valve 80-118 was closed before the CS system LCO allowed outage time expired)
~
The SSS initiated Deviation/Event Report (DER) 1-98-0851 to document this event
and to initiate a root cause analysis and identify appropriate corrective actions.
At
that time, the event was determined not reportable to the NRC.
Inspector follow-up identified that a verification checklist previously used at Unit 1,
on a shiftly basis, had been eliminated about three years ago.
The inspectors
learned that the checklist had been removed from N1-ODP-OPS-0101
because
the
control room operators did not see any benefit to the checklist based upon no
valves ever being identified as out-of-position using the checklist.
As a corrective
action, the GSO re-instituted the use of a checklist at Unit 1. The inspectors
confirmed that a system status checklist was still in use at Unit 2. After using the
new checklist for several weeks, the checklist was revised and incorporated into the
preventive maintenance
program (N1-PM-S5, "Control Room System Lineup
Verification").
Additional corrective actions for this event included a verification, using N1-OP-14,
that the other valves manipulated to lower torus level were in the proper position
and a panel walkdown (without using system operating procedures),
to ensure that
all safety systems were properly aligned in their standby configuration.
No
discrepancies
were identified. The inspectors considered the decision to conduct
the panel walkdowns without referring to the system lineups in the operating
procedures to be a weak corrective action because
of the susceptibility to human
error by verifying the safety system standby line-ups from memory. This
observation was discussed with the GSO and a second panel walkdown was
performed using the applicable operating procedures.
No discrepancies
were
.
identified.
The inspectors conducted
an independent safety system panel
walkdown using the Operational Safety Verification Checklist, developed by the
resident staff, and identified proper systems'onfiguration.
C.
Conclusions
A Unit 1 reactor operator failed to follow the operating procedure for restoration of
the containment spray system to its standby configuration resulting in the system
being in a degraded condition for 3.5 days.
This was a violation of Technical Specification 6.8.1, involving the failure to implement procedures,
as written.
(VIO 50-220/98-1 1-01 )
Between April 7 and 11, over sixty control panel walkdowns were unsuccessful
in
identifying this containment spray system mis-positioned valve.
This was a
significant operations staff oversight and indicative of a lack of attentiveness
to
safety system configuration.
In contrast, the in-plant operator's identification of the
breaker open/closed indicating lights deficiency demonstrated
good attention to
detail, proper awareness
of plant conditions, and prompt and appropriate response
to a deficient condition.
The licensee's
immediate action to conduct control panel system line-up
verifications without referring to the system operating procedures was a poorly
founded decision based upon the control room operators not having identified the
flow control valve out-of-position for 3.5 days by relying on unaided memory of
proper systems'onfiguration.
01.2
FCV 80-118 Primar
Containment Isolation Function
a ~
Ins ection Sco
e
71707
During the licensee's follow-up of the FCV 80-118 mis-position event, they
identified that FCV 80-118 is also a primary containment isolation valve (PCIV). As
such, the DER was revised and a 10 CFR 50.72 notification was made.
The
inspectors reviewed the revised DER, the LIFSAR and TSs, and discussed the issue
with Unit 1 management.
The inspectors also interviewed the SSS who made the
original reportability decision and observed the SORC meeting for the associated
Licensee Event Report (LER).
Observations
and Findin s
The system engineer's involvement in the disposition of DER 1-98-0851 resulted in
the recognition that FCV 80-118 also serves
a primary containment isolation
function. The Unit 1 UFSAR, Table Vl-3b, "Primary Containment Isolation Valves
[for] Lines Entering Free Space of the Containment," lists the normal position of
FCV 80-118 as "Closed."
FCV 80-118 is a remote manual valve and does not have
an automatic containment isolation feature.
Unit 1 TS, Section 1.11.a, defines
primary containment integrity and lists the conditions which must be satisfied.
One
of those conditions is that all non-automatic PCIVs, not required to be open for
routine plant operations, must be maintained closed.
TS Section 3.3.0 requires
primary containment to be maintained when the reactor is critical ~ The failure to
maintain primary containment integrity from April 7 through April 11, 1998, is a
violation of Technical Specifications.
(VIO 50-220/98-11-02)
In-office inspector review of the primary containment integrity TS non-compliance
identified that, although TS defined containment integrity (remote manual valves
closed) was not satisfied, containment integrity was not significantly challenged by
the open FCV 80-118.
The design of the containment spray system, as a closed
loop extension of primary containment and the inability to local leak rate test the
system's PCIVs (pre-Standard
Review Plan facility), necessitated
an NRC approved
exemption from 10 CFR 50, Appendix J, testing requirements.
Specifically, the
automatic operation of the containment spray system under design basis accident
(DBA) conditions ensures the establishment of a water seal between the primary
containment free air space
and the outside environment.
The inspectors determined
that, even under worst case single failure conditions (loss of one emergency diesel
generator and its associated
electrical bus), the water seal is maintained.
With FCV
80-118 open, the water seal is degraded
due to the diversion of flow and resultant
lower CS system developed head at the containment spray nozzles.
However, a
single operating CS pump in each loop ensures sufficient system pressure
above
containment accident pressure to provide containment integrity.
The inspectors identified that there was no TS required periodic verification of PCIV
status.
In contrast, the Unit 2 TSs have a monthly surveillance for this specific
purpose.
Following discussions with the GSO, this issue was captured in another
DER (1-98-1033) and forwarded with a recommendation to perform such a
verification at Unit 1. The inspectors consider the absence of such a verification to
be a weakness
in the Unit 1 surveillance program.
Conclusions
The identification of FCV 80-118 as a primary containment isolation valve by the
systems engineer was good, but the oversight by the operations staff of this valve's
primary containment isolation function reflects poorly on their systems knowledge
and sensitivity to containment integrity monitoring. The failure to maintain primary
containment integrity for 3.5 days was a violation of the Unit 1- Technical
Specification 3.'3.0.
(VIO 50-220/98-11-02}
08
Miscellaneous Operations Issues
08.1
Closed
LER 50-220 98-04: Containment Isolation Valve Left 0 en in Violation of
Technical S ecifications Due to Personnel
Error
90712
The events associated with this LER were described in Sections 01.1 and 01.2 of
this inspection report.
The inspectors conducted
an in-office review and verified
that the LER fulfilledthe requirements of 10CfR50.73.
Specifically, the description
and analysis of the event were consistent with the inspectors'nderstanding
of the
event.
The root cause and corrective actions described in the LER were
appropriate.
This LER is closed.
V. MANAGEMENTMEETINGS
X1
Exit Meeting Summary
At periodic intervals, and at the conclusion of the inspection period, meetings were
held with senior station management to discuss the scope and findings of this
inspection.
A preliminary exit meeting was held on May 8, during which the
inspectors initial findings were presented.
On June 10, 1998 the final exit was
held.
NMPC did not dispute any of the findings or conclusions.
Based on the NRC
Region
I review of this report, and discussions with NMPC representatives,
it was
determined that this report does not contain safeguards
or proprietary information.
ATTACHMENT1
PARTIAL LIST OF NMPC PERSONS CONTACTED
R. Abbott
B. Booth
J. Conway
P. Farsaci
T. Gardner
P. Mezzafero
J. Mueller
B. Murtha
B. Ness
R. Sanaker
R. Smith
C. Terry
D. Wolniak
Vice President,
Nuclear Engineering
General Supervisor of Operations, Unit 1
Vice President,
Nuclear Generation
Supervisor of Operations, Unit 1
Chief Shift Operator, Unit 1
Manager, Unit 1 Technical Support
Senior Vice President 5 Chief Nuclear Officer
Manager, Unit 1 Operations (Acting)
Assistant Station Shift Operator, Unit
1
Station Shift Supervisor, Unit 1
Plant Manager,:Unit
1
Vice President, Nuclear Safety Assessment
Bc Support
Manager, Licensing
INSPECTION PROCEDURES USED
IP 90712
Plant Operations
In-Office Review of Written Reports of Nonroutine Events at Power
Reactors
ITEIVIS OPENED
CLOSED AND UPDATED
OPENED
50-220/98-1 1-01
50-220/98-1 1-02
Failure to follow operating procedure for restoration of
containment spray system
Failure to maintain primary containment integrity
CLOSED
50-220/98-04
LER
Containment isolation valve left open in violation of TSs
due to personnel error
UPDATED
none
Attachment
1 (cont.)
LIST OF ACRONYMS USED
ASSS
CFR
DER
GSO
IR
LER
NRC
SORC
TS
Unit 1
Assistant Station Shift Supervisor
Code of Federal Regulations
Deviation/Event Report
Enforcement Action
Escalated Enforcement Item
Engineered Safeguards
Feature
General Supervisor of, Operations
Inspection Report
Licensee Event Report
Niagara Mohawk Power Corporation
Nuclear Regulatory Commission
Reactor Operator
Station Operating Review Committee
Senior Reactor'perator
Station Shift Supervisor
Technical Specification
Updated Final Safety Analysis Report
Nine Mile Point Unit 1
Violation
Primary Containment Isolation Valve
A-2