ML17265A206
| ML17265A206 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 03/31/1998 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML17265A204 | List: |
| References | |
| 50-244-98-02, 50-244-98-2, NUDOCS 9804070230 | |
| Download: ML17265A206 (10) | |
See also: IR 05000244/1998002
Text
U.S. NUCLEAR REGULATORY COMMISSION
REGION I
License No.
Report No.
50-244/98-02
Docket No.
50-244
Licensee:
Rochester Gas and Electric Corporation (RGRE)
Facility:
R. E. Ginna Nuclear Power Plant
II
Location:
1503 Lake Road
Ontario, New York 14519
Inspection Period:
March 3-12, 1998
Inspectors:
Herb Williams, Senior Operations Engineer, DRS (Lead)
~ Steve Dennis, Operations Engineer, DRS
Peter Drysdale, Senior Resident Inspector
Clyde Osterholtz, Resident Inspector
Approved by:
Richard J.
Conte, Chief
Operator Licensing and
Human Performance
Branch
Division of Reactor Safety
9804070230
98033i
ADQCK 05000244
6
EXECUTIVE SUMMARY
R. E. Ginna Nuclear Power Plant
NRC Inspection Report 50-244/98-02
This special inspection reviewed the event that occurred on March 3, 1998, in which the
'ressurizer pressure increased to the opening set point of a power-operated
relief valve
(PORV).
The instrument and control (ISC) calibration activities being performed before the event
were found to have been well coordinated with the operating crew.
Operator response to
the event was good after they became aware of the pressurizer pressure
increase.
There was ample time and indications of the pressure increase to allow operators to correct
the problem before the pressure increased to the point of the PORV opening.
The event
was caused by the failure of the operators to adequately monitor panels and respond to
alarms.
The failure to notice and respond to the'alarms and indications is a violation of
NRC requirements.
'(VIO 60-244/98-02-01)
RGRE management
response was quick to initiate troubleshooting of'the instrumentation
and controls, but appeared slow in reviewing the human performance aspects of the event.
RG5E investigations and corrective actions were not completed at the end of this
inspection.
The investigation included a Human Performance Evaluation System (HPES)
evaluatio'n.
The results of these activities will be reviewed in a follow-up inspection.
There were no adverse consequences
associated
with this event.
The safety importance
of the transient was that it was an unnecessary
challenge to the PORV, which could have
resulted in a small break loss of coolant accident had the PORV and its associated
block
valve failed to close.
Re ort Details
Plant Status and Back round
The plant was operating at 100% power.
On March 3, 1998, pressurizer pressure
increased to the opening setpoint of a power-operated relief valve (PORV). The pressure
increase started because
of a malfunction in the pressurizer heater control circuit during an
instrumentation calibration.
In response to this event, Region
I dispatched two inspectors to join with the resident
inspectors
in reviewing the event for underlying causes
and safety consequences.
I. 0 erations
01
Conduct of Operations
01.1
0 erator Res
onse
93702
a.
~Scc
e
The inspectors evaluated the significance of the event, the performance of plant
systems,
and the actions of reactor operators. Interviews were conducted with
instrument and controls (IKC) technicians and reactor operators involved in the
event.
a
A sequence
of events on March 3, 1998, is given in at the end of this report.
b.
Observations and Findin s
The Control Operator (CO) placed the pressurizer pressure control switch back in
automatic at 0802 hours0.00928 days <br />0.223 hours <br />0.00133 weeks <br />3.05161e-4 months <br /> as directed by the IRC calibration'procedure
and monitored
plant parameters to ensure there were no perturbations following the switch
movement.
At 0805, after observing proper response from pressurizer pressure
controls, the CO gave a briefing to the Head Control Operator (HCO) and left the "at
the controls" area to go to the restroom.
The HCO acknowledged the CO turnover
and returned to working on administrative duties at his desk in the "at the controls"
area.
These duties included performing containment leakage calculations, logging
data and entering data into the new computer log record system.
The Control Room foreman (CRF) was also performing duties in the control room at
a desk directly behind the HCO. The Shift Supervisor (SS-SRO) had previously left
the control room for a meeting.
At 0808 pressurizer pressure
began to increase from 2235 psig, unnoticed by the
HCO and CRF, and continued to increase until at 0816 it reached 2335 psig and a
power-operated
relief valve (PORV)-430 opened.
During that time period, operators
did not observe and/or acknowledge
a plant process computer system (PPCS) alarm
denoting a high pressure warning for pressurizer pressure,
main control board
indication denoting pressurizer backup heaters energized, and instrumentation
showing increasing pressurizer pressure.
The six PPCS alarms that came in were
annunciated
by a one second audible alarm and a small blinking red light in the
upper right corner of the three PPCS monitors located in the control room. The
overhead annunciator for pressurizer high'pressure
at 2310 psig did not alarm
apparently due to an ongoing malfunction in the automatic pressurizer pressure
control system.
An annunciator did alarm at 2335 psig when the PORV opened.
Interviews with operators. confirmed that the reactor coolant system (RCS) pressure
increase went unnoticed until the PORV opened and the main control board alarms
came in. Also, operators were fully aware of the IRC calibration in progress.
Responding to the overhead annunciator, the HCO by 0817 had placed pressurizer
pressure control in manual and adjusted pressure until the backup heaters were
deenergized.
The CO returned from the restroom and was the first operator to observe that PPCS
had alarmed denoting high pressurizer pressure
and the PORV had opened and
reclosed.
The CO informed the other operators of the indications and continued to
monitor plant parameters
as required.
The HCO placed manual pressurizer spray in
service to lower pressure
and by 0822 pressurizer pressure was restored to 2235
psig.
Pressurizer pressure control remained in manual to commence
evaluation/troubleshooting
of the event.
The operators followed up their immediate
response
by referencing procedure AP-PRZR.1, "Abnormal Pressurizer Pressure," to
ensure all appropriate actions had been taken.
RGS.E Ginna Station Procedure 0-6, Revision 63, "Operations and Process
Monitoring," step 5.3.3.1, requires that operators acknowledge all computer alarms
and take appropriate actions.
Station Procedure A-52.11, Revision 8, "Conduct of
Activities in the Control," requires that on-shift operators maintain awareness
of
pertinent plant instrumentation.
Reactor operators did not respond to PPCS alarms
in a timely manner, nor did they monitor control board indication adequately as
required by these procedures.
The operators'ailure to adhere to these procedures
is a violation of 10 CFR 50, Appendix B, Criterion V, "Instructions, Procedures
and
Drawings."
Conclusions
The IRC calibrations were well coordinated with the operators prior to the event.
Operators had alarms, indications, and time to respond to the pressurizer pressure
increase before the PORV opened.
The event was due to operator failure to monitor
the control boards and respond to alarms in accordance with established
procedures.
This was a violation of NRC requirements.
{VIO50-244/98-02-01)
After the control board alarms came in, the operators took prompt and effective
actions to reduce pressurized
pressure
and stabilize the plant.
I
01.2
Licensee Event Review 93702
a.
Ins ection Sco
e
The inspectors reviewed the appropriateness
of internal facility notifications, event
analysis, and corrective actions.
Also, the inspectors discussed the event with
RG &E management.
b.
Observations
and Findin s
RG&E management
response was quick to direct troubleshooting the instruments,
but appeared to be slow in reviewing the human performance aspects of the event.
The licensee initiated an ACTION Report (98-0334) on March 3rd and started on
HPES review on March 5th.
Initial troubleshooting indicated that the Pressurizer
Pressure
Defeat Switch P/429A had malfunctioned.
The licensee's review was still
in progress at the end of this inspection.
The results and corrective actions will be
reviewed in a future NRC Inspection.
It was evident to licensee management
soon after the event that operators
responded
inadequately to the plant computer alarms and had not monitored
pressurizer pressure
on the main control board.
However, a prompt review of the
human performance aspects was not initiated until 24-hours after the event
occurred.
Also, it appeared that RG&E management
did not assure that operator
performance was appropriately remediated in a timely manner to assure that
operator attentiveness to main control room indications met management
expectations.
C.
Conclusions
RG&E management
response was quick to address the plant equipment technical
aspects of the pressurizer pressure transient, but apparently slow to address the
inadequate
human performance aspects of the event.
Facility follow up actions will be reviewed in a future inspection.
(IFI 50-244/98-02-
02)
01.3
Safet
Si nificance 93702
.
a.
Ins ection Sco
e
The inspectors evaluated the increase
in risk and the safety consequences
of the
event of March 3, 1998, considering plant systems response
and operator actions.
b.
Observations
and Findin s
The safety importance of this event was that it unnecessarily challenged the PORV
and therefore, contributed to the probability of having a small break loss of coolant
accident.
This could occur if there were a combined failure of the PORV and its
block valve to close.
During this actual event, which was within the plant's design.
basis, one PORV opened for a short time and reseated without leaking.
There were
no adverse consequences.
C.
Conclusions
The PORV liftwas a design basis event with no adverse consequences.
There was
no significant increase
in risk. The event was an unnecessary
challenge to the
PORV.
E9
Review of Updated Final Safety Analysis Report {UFSAR)
The inspectors verified that the Pressurizer Pressure
Control System as described in
section 7.7.1.3.1 of the Ginna UFSAR was accurate.
V. Mana ement IVleetin s
X1
Exit Meeting Summary
RGSE was informed of the scope and purpose of this inspection at an entrance meeting on
March 5, 1998. An exit was conducted by telephone on March 12, 1998.
RGSE
acknowledged the findings identified during the inspection.
They noted that they were
considering the human performance aspects but had probably not communicated this well
to NRC staff during the early post event stages.
PARTIALLIST OF PERSONS CONTACTED
Rochester Gas 5 Electric
R. Mecredy
R. Marchionda
J. Widay
G. Wrobel
R. Smith
T. Harding
T. Laursen
A. Jones
G.
Cain
K. McLaughlin
J.
Banke
S. Stinson
K. Moynihan
K. Garnish
J.
Hamm
T. Fouts
Vice President,
Nuclear Operations
Production Superintendent
Plant Manager
Nuclear Safety S. Licensing Manager
Senior Vice President,
Energy Operations
Senior Licensing Engineer
Operating Experience Engineer
0'perating Experience Engineer
System Engineer
Shift Supervisor
System Engineer
ISC Foreman
IRC Technician
Control Room Foreman
Control Room Operator
Head Control Operator
INSPECTION PROCEDURES USED
IP 93702, Prompt Onsite Response to Events at Operating Power Reactors
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
~Oened
50-244/98-02-01
50-244/98-02-02
Failure to monitor control room panels and attend to alarms
IFI
Review the licensee's event review'and corrective actions for
the pressurizer pressure transient.
EVENT DESCRIPTION
Alltimes on March 3, 1998
NOTE:
Times and values are approximate and based on computer alarm reports and
chart recorder interpretation.
0731
IRC technicians began calibration procedure CPI-TRIP-TEST-5.30, "Reactor
Protection System Trip Test/Calibration for Channel 3 Bistable Alarms."
0808
Pressurizer backup heaters energized; indicated by a red light illuminated on
main control board.
Pressurizer pressure
begins to increase from 2235 psig
as indicated on main control board instrumentation (indicators and recorder),
0810
Plant Process Computer System (PPCS) alarmed when pressurizer pressure
increased to 2260 psig. A total of 4 alarms were received, one for each of
the 3 remaining valid pressure channels and
1 for average pressurizer
pressure.
0812
PPCS alarmed when pressurizer pressure increased to 2285 psig.
0814
PPCS alarmed when pressurizer average pressure increased to 2310 psig.
Main control board overhead annunciator F-2, PRESSURIZER HIGH
PRESSURE, failed to annunciate at its set point of 2310 psig.
0816
Pressurizer pressure
increased to 2335 psig.
PORV 430 opened and
reclosed about two seconds later.
Main control board overhead annunciators
alarmed for PRESSURIZER HIGH PRESSURE, PRESSURIZER RELIEF TANK
(PRT) HIGH PRESSURE, and PORV OUTLET HIGH TEMPERATURE (expected
due to PORV lift). Pressurizer pressure initiallydecreased to 2315 psig and
began to rise after the PORV closed.
0817
Operators took manual control of pressurizer pressure,
deenergized
backup
heaters,
and began to reduce pressurizer pressure
using spray.
0822
Pressurizer pressure restored to 2235 psig.