ML061700510
ML061700510 | |
Person / Time | |
---|---|
Site: | River Bend |
Issue date: | 06/19/2006 |
From: | Howell A NRC/RGN-IV/DRP |
To: | Hinnenkamp P Entergy Operations |
References | |
EA-06-103 IR-06-011 | |
Download: ML061700510 (26) | |
See also: IR 05000458/2006011
Text
June 19, 2006
Paul D. Hinnenkamp
Vice President - Operations
Entergy Operations, Inc.
River Bend Station
5485 US Highway 61N
St. Francisville, Louisiana 70775
SUBJECT: RIVER BEND STATION - NRC INSPECTION REPORT 05000458/2006011;
Dear Mr. Hinnenkamp:
On May 10, 2006, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at
your River Bend Station. The purpose of the inspection was to assess the impact that the
removal of seismic monitor instrumentation from service had on the ability of River Bend Station
personnel to make an accurate and timely emergency action level classification following a
seismic event. The enclosed inspection report documents an inspection finding which was
discussed on May 10, 2006, with you and other members of your staff.
The report discusses a finding that appears to have low to moderate safety significance. As
described in Section 1EP04 of this report, this issue involved a failure to ensure that adequate
preplanned measures were in place to ensure accurate and timely emergency classification
using seismic activity emergency action levels during periods when seismic monitoring
instrumentation was out of service at various times in 2004 and 2005. With certain seismic
monitor instrumentation removed from service, the River Bend Station Emergency Plan would
not provide adequate direction to station personnel to declare a Site Area Emergency following
a seismic event. This finding was assessed based on the best available information using the
applicable Significance Determination Process and was preliminarily determined to be a White
finding.
This finding does not present a current safety concern because your staff returned the seismic
monitors to an operable condition. Additionally, your staff issued Standing Order 194 on
April 11, 2006, which provided preplanned measures for implementing the Emergency Plan
emergency action levels should the seismic monitors be removed from service.
This finding is also an apparent violation of NRC requirements and is being considered for
escalated enforcement action in accordance with the NRC Enforcement Policy. The
current enforcement policy is included on the NRCs website at
http://www.nrc.gov/what-we-do/regulatory/enforcement.html.
Entergy Operations, Inc. -2-
Before the NRC makes a final decision on this matter, we are providing you an opportunity to:
(1) present to the NRC your perspectives on the facts and assumptions, used by the NRC to
arrive at the finding and its significance, at a Regulatory Conference or (2) submit your position
on the finding to the NRC in writing. We note that a position paper was provided to the NRC on
April 18, 2006, related to the safety significance and regulatory considerations associated with
this issue. The NRC will consider this information prior to making a final decision on this
matter. If you request a Regulatory Conference, it should be held within 30 days of the receipt
of this letter and we encourage you to submit any additional supporting documentation at least
one week prior to the conference in an effort to make the conference more efficient and
effective. If a Regulatory Conference is held, it will be open for public observation. If you
decide to submit only a written response, such submittal should be sent to the NRC within
30 days of the receipt of this letter.
Regardless of the method you select to present your position on this matter, we request that
you specifically discuss the procedures that existed at River Bend Station, the training provided
to Operations Shift Managers and Emergency Directors, and the specific methods (including
data sources) that would be utilized by personnel to make an accurate and timely emergency
action level classification following a seismic event during the periods that seismic monitoring
instrumentation was out of service.
Please contact Mr. Kriss Kennedy at (817) 860-8144 within 10 business days of the date of this
letter to notify the NRC of your intentions. If we have not heard from you within 10 days, we will
continue with our significance determination and enforcement decision and you will be advised
by separate correspondence of the results of our deliberations on this matter.
Since the NRC has not made a final determination in this matter, no Notice of Violation is being
issued for the inspection finding at this time. In addition, please be advised that the
characterization of the apparent violation described in the enclosed inspection report may
change as a result of further NRC review.
In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter, its
enclosure, and your response will be made available electronically for public inspection in the
NRC Public Document Room or from the Publicly Available Records (PARS) component of
NRCs document system (ADAMS). ADAMS is accessible from the NRC Web site at
http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Should you have any questions concerning this inspection, we will be pleased to discuss them
with you.
Sincerely,
/RA/
Arthur T. Howell III, Director
Division of Reactor Projects
Entergy Operations, Inc. -3-
Docket: 50-458
License: NPF-47
Enclosure:
NRC Inspection Report 05000458/2006001
w/attachments
cc w/enclosure:
Senior Vice President and
Chief Operating Officer
Entergy Operations, Inc.
P.O. Box 31995
Jackson, MS 39286-1995
Vice President
Operations Support
Entergy Operations, Inc.
P.O. Box 31995
Jackson, MS 39286-1995
General Manager
Plant Operations
Entergy Operations, Inc.
River Bend Station
5485 US Highway 61N
St. Francisville, LA 70775
Director - Nuclear Safety
Entergy Operations, Inc.
River Bend Station
5485 US Highway 61N
St. Francisville, LA 70775
Wise, Carter, Child & Caraway
P.O. Box 651
Jackson, MS 39205
Winston & Strawn LLP
1700 K Street, N.W.
Washington, DC 20006-3817
Manager - Licensing
Entergy Operations, Inc.
River Bend Station
5485 US Highway 61N
St. Francisville, LA 70775
Entergy Operations, Inc. -4-
The Honorable Charles C. Foti, Jr.
Attorney General
Department of Justice
State of Louisiana
P.O. Box 94005
Baton Rouge, LA 70804-9005
H. Anne Plettinger
3456 Villa Rose Drive
Baton Rouge, LA 70806
Bert Babers, President
West Feliciana Parish Police Jury
P.O. Box 1921
St. Francisville, LA 70775
Richard Penrod, Senior Environmental
Scientist
Office of Environmental Services
Northwestern State University
Russell Hall, Room 201
Natchitoches, LA 71497
Brian Almon
Public Utility Commission
William B. Travis Building
P.O. Box 13326
1701 North Congress Avenue
Austin, TX 78711-3326
Chairperson
Denton Field Office
Chemical and Nuclear Preparedness
and Protection Division
Office of Infrastructure Protection
Preparedness Directorate
Dept. of Homeland Security
800 North Loop 288
Federal Regional Center
Denton, TX 76201-3698
Entergy Operations, Inc. -5-
Electronic distribution by RIV:
Regional Administrator (BSM1)
DRP Director (ATH)
DRS Director (DDC)
DRS Deputy Director (RJC1)
Senior Resident Inspector (PJA)
Branch Chief, DRP/C (KMK)
Senior Project Engineer, DRP/C (WCW)
Team Leader, DRP/TSS (RLN1)
RITS Coordinator (KEG)
S. O'Connor, OEDO RIV Coordinator (SCO)
ROPreports
RBS Site Secretary (LGD)
W. A. Maier, RSLO (WAM)
K. S. Fuller, RC/ACES (KSF)
M. R. Johnson, D:OE (MRJ1)
OE:EA File (RidsOeMailCenter)
SUNSI Review Completed: ______ ADAMS: G Yes G No Initials: ______
- Publicly Available G Non-Publicly Available G Sensitive : Non-Sensitive
R:\_REACTORS\_RBS\2006\RB2006-011RP-PJA.wpd
RIV:RI SRI C:DRS/OB Senior Enf. Spec. C:DRP/C lD:DRP
MOMiller PJAlter ATGody GMVasquez KMKennedy lATHowell III
T - KMK E - KMK /RA/ E - MHaire /RA/ l /RA/
6/19/06 6/19/06 6/15/06 6/19/06 6/15/06 l6/19/06
OFFICIAL RECORD COPY T=Telephone E=E-mail F=Fax
U.S. NUCLEAR REGULATORY COMMISSION
REGION IV
Docket: 50-458
License: NPF-47
Report: 05000458/2006011
Licensee: Entergy Operations, Inc.
Facility: River Bend Station
Location: 5485 U.S. Highway 61
St. Francisville, Louisiana 70775
Dates: May 3-10, 2006
Inspectors: P. Alter, Senior Resident Inspector, Project Branch C
M. Miller, Resident Inspector, Project Branch C
Approved By: K. M. Kennedy
Chief, Project Branch C
-1- Enclosure
SUMMARY OF FINDINGS
IR 05000458/2006011; 05/03/2006 - 05/10/2006; River Bend Station; Emergency Action Level
and Emergency Plan Changes
The report documents the NRCs inspection of the impact that the removal of seismic monitor
instrumentation from service had on the ability of River Bend Station personnel to make an
accurate and timely emergency action level classification following a seismic event. During this
inspection, a finding was identified which was preliminarily determined to be of low to moderate
safety significance (White). The significance of most findings is indicated by their color (Green,
White, Yellow, Red) using Inspection Manual Chapter 0609, Significance Determination
Process. The NRC's program for overseeing the safe operation of commercial nuclear power
reactors is described in NUREG-1649, Reactor Oversight Process, Revision 3, dated July
2000.
A. NRC-Identified and Self-Revealing Findings
Cornerstone: Emergency Preparedness
- TBD. An apparent violation of 10 CFR 50.54(q) was identified for the licensees failure
to ensure that adequate preplanned measures for Emergency Plan Emergency Action
Levels were in place when seismic monitoring instrumentation was out of service at
various times in 2004 and 2005. The seismic monitoring equipment was required to
ensure the prompt implementation of the River Bend Emergency Plan as required by
10 CFR 50.54(q) and the risk significant planning standard function,10 CFR 50.47(b)(4).
The issue was entered into the licensees corrective action program as
The finding was more than minor because it is associated with the procedure quality
attribute of the Emergency Preparedness Cornerstone objective to ensure that the
licensee is capable of implementing adequate measures to protect the health and safety
of the public in the event of a radiological emergency. Utilizing the Failure to Comply
flow chart in Manual Chapter 0609, Appendix B, Emergency Preparedness Significance
Determination Process, the inspectors determined that the finding was a failure to
comply with an NRC requirement and was a Risk-Significant Planning Standard
Problem involving a degraded Risk-Significant Planning Standard Function. The
performance deficiency represents a degraded risk-significant planning standard
function in that, during the periods that Reactor Mat Response Spectrum Recorder
ERS-NBR2D or Free Field Seismic Trigger ERS-NBS4A were out of service, an existing
Site Area Emergency emergency action level would not be declared. Based on the
results of this evaluation, the finding was preliminarily determined to be of low to
moderate safety significance (Section 1EP04).
-2- Enclosure
REPORT DETAILS
Summary of Plant Status: The plant was shut down for Refueling Outage 13 during this
inspection.
REACTOR SAFETY
Cornerstone: Emergency Preparedness
1EP04 Emergency Action Level (EAL) and Emergency Plan Changes
a. Inspection Scope
On January 15, 2006, during a review of a seismic monitor surveillance performed on
November 10, 2005, conducted in accordance with Surveillance Test Procedure STP-
557-4209, Seismic Monitoring - Reactor BLDG MAT EL 70' 0", Triaxial Response
Spectrum Recorder Channel Calibration Test (ERS-NBR2D, ERS-NBI101),
Revision 07D, the inspectors noted that the procedure required removal of Reactor Mat
Response Spectrum Recorder ERS-NBR2D from service. Reactor Mat Response
Spectrum Recorder ERS-NBR2D provides input to Control Room Annunciator P680-
02A-B06, Seismic Event High-High. This annunciator, in turn, is an initiating condition
listed in Emergency Plan Implementing Procedure EIP-2-001, Classification of
Emergencies, Revision 12, Attachment 3, Alert, EAL 14, Severe Natural Phenomena
Experienced Beyond Notification of Unusual Event Levels, and Attachment 4, Site
Area Emergency, EAL 13, Severe Natural Event Near Site Being Experienced or
Projected with Plant Not in Cold Shutdown.
The inspectors observed that the test procedure did not require, and the licensee had
not taken any actions to ensure that, with Reactor Mat Response Spectrum Recorder
ERS-NBR2D removed from service, the emergency response organization could identify
the initiating conditions for an Alert or Site Area Emergency in an accurate and timely
manner.
As a result of these observations, the inspectors reviewed work control records and
control room and Technical Specification log entries for similar instances when seismic
monitoring instruments were removed from service. The inspectors reviewed the River
Bend Station Emergency Plan and Emergency Plan Implementing Procedures (EIP) to
determine what actions should have been taken, reviewed condition reports (CRs), and
questioned operators and members of the emergency preparedness staff with respect
to the consequences of removing these instruments from service.
b. Findings
Introduction: The inspectors identified an apparent violation of 10 CFR 50.54(q) and
10 CFR 50.47(b)(4) for the failure of the licensee to ensure that adequate preplanned
measures were in place for the accurate and timely classification of Emergency Plan
EALs during periods when seismic monitoring instrumentation was out of service in
2004 and 2005.
-3- Enclosure
Description: River Bend Station Procedure EIP-2-001, Classification of Emergencies,
Revision 12, described the initiating conditions under which seismic activity would
require the declaration of a Notification of Unusual Event (NOUE), Alert, or Site Area
Emergency (SAE). The initiating conditions for the various EALs related to seismic
events, and the seismic monitors that provide input to the indications, are listed below:
Emergency Action Level Initiating Condition Seismic Monitor Input
Notification of Unusual Event
Unusual Natural Events Receipt of annunciators Reactor Mat Seismic
Near Site Seismic Event High Switch ERS-NBS4B
(P680-02A-C06)
AND
Seismic Tape Recording Free Field Seismic
System Start Trigger ERS-NBS4A
(P680-02A-D06)
Alert
Severe Natural Receipt of annunciators Reactor Mat Response
Phenomena Experienced Seismic Event High-High Spectrum Recorder
Beyond Notification of (P680-02A-B06) ERS-NBR2D
Unusual Event Levels AND
Seismic Tape Recording Free Field Seismic
System Start Trigger ERS-NBS4A
(P680-02A-D06)
AND
Amber light(s) on Panel Reactor Mat Response
NBI-101 Spectrum Recorder
ERS-NBR2D
Site Area Emergency
Severe Natural Event Receipt of annunciators Reactor Mat Response
Near Site Being Seismic Event High-High Spectrum Recorder
Experienced or Projected (P680-02A-B06) ERS-NBR2D
With Plant Not in Cold AND
Shutdown Seismic Tape Recording Free Field Seismic
System Start Trigger ERS-NBS4A
(P680-02A-D06)
AND Reactor Mat Response
Red light(s) on Panel Spectrum Recorder
NBI-101 ERS-NBR2D
The inspectors found that the licensee had removed seismic monitoring instrumentation
from service on numerous occasions during 2004 and 2005 without providing adequate
measures for the Operations Shift Manager, as Emergency Director, to assess plant
-4- Enclosure
conditions against the criteria in EIP-2-001, Classification of Emergencies,
Revision 12, for determining the appropriate EAL for a seismic event.
From January 19 to August 26, 2004, Free Field Seismic Trigger ERS-NBS4A was out
of service for 216 days over a period of 220 days because of the planned demolition of
concrete. Free Field Seismic Trigger ERS-NBS4A provides input to the Seismic Tape
Recording System Start (P680-02A-D06) annunciator. (The seismic Tape Recording
System records the output signals from four seismic accelerometers for postevent
playback and analysis.) Thus, with this instrument out of service, the Operations Shift
Manager could not have determined if a seismic event met the criteria for declaring a
NOUE, Alert, or SAE using Emergency Plan Implementing Procedure EIP-2-001,
Classification of Emergencies, Revision 12, Attachment 2, Notification of Unusual
Event; Attachment 3, Alert; or Attachment 4, Site Area Emergency. During this
period that Free Field Seismic Trigger ERS-NBS4A was out of service, Reactor Mat
Response Spectrum Recorder ERS-NBR2D was also out of service for a total of
20 days because of a planned surveillance in one instance and an instrument
malfunction in another. Reactor Mat Response Spectrum Recorder ERS-NBR2D
provides input to the Seismic Event High-High (P680-02A-B06) annunciator and the
amber and red lights on Panel NBI-101. Thus, with this instrument out of service, the
Operations Shift Manager could not have determined if a seismic event met the criteria
for declaring an Alert or SAE using Procedure EIP-2-001, Classification of
Emergencies, Revision 12, Attachment 3, Alert or Attachment 4,Site Area
Emergency.
From July 29 to September 22, 2004, Reactor Mat Seismic Switch ERS-NBS4B was out
of service for 35 days over a period of 55 days due to a failed surveillance in one
instance and the discovery that a wrong part had been installed in another instance.
Reactor Mat Seismic Switch ERS-NBS4B provides input to the Seismic Event High
(P680-02A-C06) annunciator. Thus, with this instrument out of service, the Operations
Shift Manager could not have determined if a seismic event met the criteria for declaring
a NOUE using Procedure EIP-2-001, Classification of Emergencies, Revision 12,
Attachment 2, Notification of Unusual Event.
The inspectors also found that between January 17 and March 2, 2005, Free Field
Seismic Trigger ELS-NBS4A was out of service for 32 days in a 44-day period for
maintenance; Reactor Mat Response Spectrum Recorder ERS-NBR2D was out of
service for 16 days from October 25 to November 10, 2005, for a surveillance; and
Reactor Mat Seismic Switch ERS-NBS4B was out of service for 22 days from
February 8, 2005, to March 2, 2005, for a surveillance.
The inspectors determined that the River Bend Station Emergency Plan did not provide
adequate instructions to the Operations Shift Manager or Emergency Director to make
an accurate and timely EAL classification following a seismic event during the periods
that seismic monitoring instrumentation was out of service. The inspectors noted,
however, that each time the seismic monitoring instruments were out of service, the
operators entered the appropriate Technical Requirements Manual (TRM) Limiting
Condition for Operation. Technical Requirement 3.3.7.5, Seismic Monitoring
Instrumentation, required that, with one or more seismic monitoring instruments
-5- Enclosure
inoperable, actions be taken within 30 days to restore the affected monitor to operable
status. If the affected instrument was not returned to service within 30 days, then
Technical Requirement 3.3.7.5 directed personnel to initiate action to prepare an
appropriate deficiency document. CR-RBS-2004-00823 was written on March 17, 2004,
to document the inoperability of Free Field Seismic Trigger ERS-NBS4A. The condition
report did not identify the impact that the inoperable instrument had on implementation
of the River Bend Station Emergency Plan, and did not require any actions related to the
condition. CR-RBS-2004-02712 was written on September 18, 2004, to document the
inoperability of Reactor Mat Seismic Switch ERS-NBS4B. The CR did not identify the
impact that the inoperable instrument had on implementation of the River Bend Station
Emergency Plan and did not require any actions related to the condition.
Based on a review of licensee training material and interviews with plant personnel, the
inspectors determined that Operations Shift Managers and Emergency Directors had
not received training on how to implement the River Bend Station Emergency Plan and
properly classify seismic events in a timely manner during periods when the seismic
monitors were out of service. In addition, licensee procedures did not provide specific
instructions on what criteria the Operations Shift Manager or Emergency Director should
utilize to classify a seismic event during periods when seismic monitoring was out of
service. The inspectors noted that personnel were not trained, nor direction provided,
on methods to assess the magnitude of a seismic event during periods when seismic
monitor Recorder ERS-NBR2D was out of service. The correlation between an
Operating Basis Earthquake (OBE, ground acceleration of 0.05 g) and an Alert, and a
Safe Shutdown Earthquake (SSE, ground acceleration of 0.1 g) and a SAE was not
explained in licensee procedures. The licensee informed the inspectors that they
believed there was sufficient guidance provided in the River Bend Station alarm
response procedures, surveillance procedures, and Procedure EIP-02-001 (allowing the
Emergency Director to use his own judgment in assessing plant conditions against the
Emergency Plan EAL schemes) for the Operations Shift Manager or Emergency
Director to make an accurate and timely event classification during the periods that
these instruments were out of service. However, based on inspector interviews, three
shift managers were unable to demonstrate that they would make the correct event
classification if Recorder ERS-NBR2D was out of service.
The inspectors noted that NRC Information Notice 2005-19, Effect of Plant
Configuration Changes on the Emergency Plan, issued on July 18, 2005, described
instances in which licensees failed to properly evaluate the effect of plant configuration
changes (procedures, equipment, and facilities) on the Emergency Plan, including the
failure to identify the impact of equipment deficiencies on the Emergency Plan. The
Notice stated that Site configuration changes should be evaluated to ensure that the
licensee continuously maintains the ability to implement an effective emergency plan.
Configuration changes that impact the ability of a site to implement its emergency plan
need to be evaluated to determine the impact and, if necessary, to implement
compensatory measures. The inspectors reviewed the licensees evaluation of NRC
Information Notice 2005-19 documented in CR LO-OPX-2005-00241, Corrective
Action 6. The licensees evaluation concluded that their plant modification process and
procedure change process provided a cross-discipline review, including the emergency
-6- Enclosure
preparedness organization, for any permanent plant equipment or procedure change.
However, the licensees evaluation did not address instances in which equipment was
out of service for other planned or unplanned reasons.
The inspectors reviewed Condition Report LO-OPX-2004-00224, initiated on
October 11, 2004, in which the licensee documented their evaluation of an emergency
preparedness peer group recommendation that licensees evaluate conditions when
instruments used to determine EALs are temporarily out of service for extended periods
of time. Specific reference was made to an NRC finding at another site that a licensee
removed a seismic monitor from service without evaluating its impact on the seismic
event EAL classification scheme. In their evaluation, River Bend Station personnel
stated that operators routinely contact the emergency preparedness staff when
performing an operability and reportability review for CRs or when reviewing
maintenance requests associated with equipment used to implement the Emergency
Plan, and that significant equipment outages are identified and compensatory actions
are built into the Emergency Plan Implementing Procedures, as needed. The inspectors
noted that neither of these actions were taken during the periods that seismic monitoring
instrumentation was out of service during the periods previously described.
In response to this finding, the licensee wrote Condition Report CR-RBS-2006-01283.
The licensee stated that they did not agree with the inspectors characterization of the
issue and did not believe a violation of regulatory requirements had occurred. The
licensee documented their position in Regulatory Position Regarding Seismic
Monitoring Instrumentation Allowed Outage Time, and provided a copy to the
inspectors. The licensees position paper is attached to this report.
In their position paper, the licensee concluded that they were confident that operators
would implement existing site procedures, evaluate available seismic instruments, be
sensitive to physical parameters, request site engineering assistance, and call upon
offsite seismology resources enabling the station to determine the magnitude of an
event and permit classification. They also believed that past performance served as
validation, using existing Alarm Response Procedures, shift briefings, and physical
indications of a seismic event, that appropriate actions would be taken to protect the
plant as well as the health and safety of the public.
In their paper, the licensee stated that a seismic event is by nature a self-revealing
event that the operators would have adequate indication of seismic activity and there
would be alarms in the control room for oscillating pool levels. The Operations Shift
Manager would then consult the seismic monitor alarm response procedures for the
disabled instruments and would be directed to Procedure STP-557-3700, Seismic
Event Report, where guidance is given to consult with the National Earthquake
Information Center. The Operations Shift Manager would then use the information
provided to assess the severity of the seismic activity against the criteria for the Alert
In response to the inspectors observations, the licensee contacted the National
Earthquake Information Center and found that the information provided by the Center on
the magnitude of seismic activity would be for the seismic epicenter location based on
-7- Enclosure
the Richter Scale, which was not easily correlated to ground motion acceleration at
River Bend Station. The inspectors also noted that there was no direct correlation
between actual ground motion acceleration and the seismic event EALs in either
Procedure EIP-02-001 or the seismic monitor alarm response procedures. In order for
the Operations Shift Manager to make this correlation, he would have to know that the
Alert EAL corresponds to an OBE and that an SAE corresponds to an SSE. He would
then have to look up the definitions of OBE and SSE in the Updated Safety Analysis
Report (USAR) and relate that data to the information provided from the National
Earthquake Information Center. The inspectors determined that this effort would not
meet the requirements of Emergency Plan Section 13.3.7, Maintaining Emergency
Preparedness, which states, in part, The EIPs contain detailed information extracted
from this plan and other pertinent documents. These procedures will enable station
personnel to implement this plan and take proper action without referral to numerous
documents. On April 11, 2006, Standing Order 194 was issued to provide specific
guidance for the Operations Shift Managers to contact the National Earthquake
Information Center following sensed seismic activity when the required seismic monitors
were out of service and how to interpret the information provided with respect to the
seismic event EAL criteria in Procedure EIP-2-001.
In their paper, the licensee stated that River Bend Station TRM Section 3.3.7.2, provided
for a 30-day allowed outage time for the seismic monitoring instruments to perform
maintenance or be removed from service. The TRM did not provide any specific actions
to be taken while an instrument was out of service. The inspectors noted that the TRM
action statement does not obviate the need to comply with 10 CFR 50.47(b)(4). The
licensee also documented that the NRC has stated in Emergency Planning Position 1,
dated June 1, 1995, that Standard technical specifications allow a plants seismic
monitoring system to be out of service for days. In addition, loss of instrumentation
does not represent a significant loss of assessment capability. The inspectors review
of Emergency Preparedness Position No. 1 found that the NRC was stating that
licensees could remove the requirement to enter a NOUE when seismic activity
assessment capability is lost due to instrumentation being out of service and that it did
not relate to the requirement to maintain the seismic event EAL scheme at all times,
particularly with respect to the ability to classify seismic events at the Alert or SAE level.
The licensees position paper also referenced Regulatory Guide 1.166, Pre-Earthquake
Planning and Immediate Nuclear Power Plant Operator Postearthquake Actions, dated
March 1997, which described a method for evaluating on-site seismic activity to
determine if an OBE has occurred when seismic instrumentation is not available. The
licensees position was that the NRC was acknowledging that seismic instrumentation
was permitted to be out of service. The inspectors reviewed the guidance provided by
Regulatory Guide 1.166 for evaluating whether an OBE had occurred and determined
that this guidance was provided to assist the licensee in determining whether or not the
plant was required to be shut down following seismic activity greater than OBE. It did
not provide guidance to assist licensees in making an accurate and timely emergency
classification following a seismic event. The inspectors also noted that this guidance
was not available in any station procedure, the USAR, or the Emergency Plan, and
operators had not been trained on its use.
-8- Enclosure
Analysis: The failure to provide adequate measures and instructions to enable the
Operations Shift Manager or Emergency Director to make accurate and timely
emergency classifications during periods when seismic monitoring instrumentation was
out of service was determined to be a performance deficiency. The finding was more
than minor because it is associated with the procedure quality attribute of the
Emergency Preparedness Cornerstone objective to ensure that the licensee is capable
of implementing adequate measures to protect the health and safety of the public in the
event of a radiological emergency. The licensees failure to reliably classify seismic
events could result in the failure to adequately protect members of the public and
nonemergency workers at River Bend Station and impacts offsite authorities ability to
implement measures to protect the health and safety of the general public. Utilizing the
Failure to Comply flow chart in Manual Chapter 0609, Appendix B, Emergency
Preparedness Significance Determination Process, the inspectors determined that the
finding was a failure to comply with an NRC requirement and was a Risk-Significant
Planning Standard Problem involving a degraded Risk-Significant Planning Standard
Function. The performance deficiency represents a degraded risk-significant planning
standard function in that, during the periods that Reactor Mat Response Spectrum
Recorder ERS-NBR2D or Free Field Seismic Trigger ERS-NBS4A were out of service,
an existing EAL would not be declared for a Site Area Emergency. As a result, the
finding was preliminarily determined to be of low to moderate safety significance
(White).
Enforcement: Title 10 CFR 50.54 (q) requires, in part, that a licensee shall follow and
maintain in effect emergency plans which meet the planning standards in
Section 50.47(b). Risk significant planning standard 10 CFR 50.47(b)(4) requires that a
standard scheme of emergency classification and actions levels be in use. Contrary to
this, at various times in 2004 and 2005, the licensee failed to maintain a standard
scheme of emergency classification and action levels in use. Specifically, River Bend
Station failed to ensure that adequate preplanned measures were in place for evaluating
the Emergency Plan EALs when seismic monitoring instrumentation was out of service.
The licensee entered this issue into their corrective action program as CR-RBS-2006-
01283. On April 11, 2006, Standing Order 194 was issued as an interim measure to
provide specific guidance for the Operations Shift Managers to contact the National
Earthquake Information Center following seismic activity and how to interpret the
information provided against the seismic event EAL criteria of Procedure EIP-2-001,
Classification of Emergencies. This violation of 10 CFR 50.54(q), was identified as an
apparent violation (AV 05000458/2006011-01), Failure to Maintain a Standard Scheme
of Emergency Classification and Action Levels in Use.
4OA6 Meetings, Including Exit
On May 10, 2006, the inspectors presented the results of the inspection to Paul
Hinnenkamp, Vice President - Operations, and other members of his staff who
acknowledged the finding.
The inspectors confirmed that proprietary information was not provided by the licensee
during this inspection.
-9- Enclosure
ATTACHMENTS: SUPPLEMENTAL INFORMATION
LICENSEE POSITION PAPER
-10- Enclosure
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee Personnel
P. Hinnenkamp, Vice President - Operations
R. King, Director, Nuclear Safety Assurance
J. Leavines, Manager, Emergency Planning
D. Lorfing, Manager, Licensing
J. Miller, Manager, Training and Development
C. Stafford, Manager, Operations
D. Vinci, General Manager - Plant Operations
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
Opened
05000458/2006011-01 AV Failure to Maintain a Standard Scheme of Emergency
Classification and Action Levels in Use
LIST OF DOCUMENTS REVIEWED
Section 1EP04: Emergency Action Level and Emergency Plan Changes
Control Room Logs
Technical Specification (TRM) Entry Logs
Operations Standing Order 194, Interim Actions for a Seismic Event with Seismic
Instrumentation Out Of Service, dated April 11, 2006
STP-557-3700, Seismic Event Report, Revision 03A
STP-557-4209, Seismic Monitoring - Reactor BLDG MAT EL 70' 0", Triaxial Response
Spectrum Recorder Channel Calibration Test (ERS-NBR2D, ERS-NBI101), Revision 07D
Alarm Response Procedure, ARP-680-02, P680-02 Alarm Response, Revision 15A
EIP-2-001, Classification of Emergencies, Revision 12
River Bend Station Emergency Plan
River Bend Station USAR
System Training Manual - 557, Seismic Monitoring System
A1-1 Attachment
NRC Information Notice 2005-19, Effect of Plant Configuration Changes on the Emergency
Plan, dated July 18, 2005
Regulatory Guide 1.12, Nuclear Power Plant Instrumentation for Earthquakes, dated March
1997
Regulatory Guide 1.166, Pre-Earthquake Planning and Immediate Nuclear Power Plant
Operator Post-Earthquake Actions, March 1997
NRC Emergency Preparedness Position on Acceptable Deviations from Appendix 1 of
NUREG 0654, based upon the Staffs Regulatory Analysis of NUMARC/NESP-007,
Methodology for Development of Emergency Action Levels, dated June 1, 1995
Condition Reports
CR-RBS-2006-01283 CR-RBS-2002-00483
CR-RBS-2004-00483 CR-RBS-2002-01723
CR-RBS-2006-00337 CR-RBS-2004-02712
CR-RBS-2004-00823 LO-OPX-2004-00142
CR-RBS-1991-00510 LO-OPX-2004-00224
LIST OF ACRONYMS
AV apparent violation
CR condition report
EAL emergency action level
EIP emergency plan implementing procedure
NOUE Notification of Unusual Event
OBE operating basis earthquake
SAE site area emergency
TRM Technical Requirements Manual
USAR Updated Safety Analysis Report
A1-2 Attachment
Regulatory Position Regarding Seismic Monitoring Instrumentation Allowed
Outage Time
NRC has stated in an exit meeting that River Bend Station must have compensatory
measures in place whenever the station removes from service any of its seismic
monitoring equipment. Additionally, NRC stated that, Emergency Implementing
Procedures are inadequate in that the appropriate EAL cannot be determined when the
instrumentation is out of service given no compensatory action was implemented.
RBS is dedicated to fully and effectively implementing all elements of its Emergency
Plan and procedures. During this inspection activity, NRC has identified areas where
RBS believes enhancements could be made. RBS has improved the clarity and linkage
of existing information within our Alarm Response Procedures, Emergency
Implementing Procedures and Surveillance Test Procedures.
This position is being prepared to evaluate the regulatory implications of temporarily
removing seismic monitoring equipment from service at River Bend Station (RBS) as
allowed by TR 3.3.7.5 while complying with Required Action A.1. The stations
Technical Requirements Manual (TRM) requires the instruments to be removed from
service periodically for maintenance/testing.
RBS believes that the NRC positions referred to in this paper are taken with the
knowledge that the allowed outage time for the seismic monitoring system used for
Emergency Action Level (EAL) determination, would be subject to the requirements of a
Discussion
It should be recognized that a seismic event is by nature self-revealing and would
cause plant operators to immediately initiate actions to assess the event by all means
available. The Operating Bases Earthquake (OBE) and the Safe Shutdown Earthquake
(SSE) are such that instrumentation would not be the only means to determine that an
event of sufficient nature to be classified within the stations Emergency Action Level
scheme has occurred.
EIP-02-001, Revision 13, Classification of Emergencies provides the following
guidance:
q Event Category N, Emergency Action Level 10 - Unusual natural events near
site (NOUE), Initiating Condition 1:
o Receipt of annunciator Seismic Event High (P680-02A-C06) AND
o Seismic Tape Recording System Start (P680-02A-DO6)
A2-1 Attachment
q Event Category N, Emergency Action Level 14- Severe natural phenomenon
experienced beyond Notification of Unusual Event levels (ALERT), Initiating
Condition 1:
o Receipt of annunciator Seismic Event High-High (P680-02A-B06) AND
o Seismic Tape Recording System Start (P680-02A-D06) AND
o Amber Light (s) on panel NBI-101
q Event Category N, Emergency Action Level 13 - Severe Natural Event Near
Site Being Experienced or Projected with Plant Not in Cold Shutdown (SAE),
Initiating Condition 1:
o Receipt of annunciator Seismic Event High-High (P680-02A-B06) AND
o Seismic Tape Recording System Start (P680-02A-D06) AND
o Red light (s) on panel NBI-101
This guidance provides the expected instrumentation that may indicate a seismic event
and allows classification of the event and in no way restricts the use of felt physical
indicators of an event.
Existing Alarm Response Procedures coupled with Surveillances, provide sufficient
information to enable the operators (Emergency Director) to contact the National
Earthquake Information Center1 and gain station engineering assistance as needed.
The National Earthquake Center will provide specific information relative to the
magnitude of an event to be used to aid in classification.
Additionally, Emergency Implementing Procedure, EIP-2-001, Classification of
Emergencies contains the following guidance to an Emergency Director:
For Emergency Action Levels based on plant instrumentation, the indication
shall be a valid indication. When all indications for a certain parameter have
been lost, the Emergency Director should use his best judgment and other plant
indications to classify the emergency (e.g., loss of level trend on all RPV level
instrumentation).
The station operations department past performance has demonstrated that the
expected behaviors related to seismic event response could reasonably be expected to
recur. For example, on November 3rd, 2002, the main control room received multiple
alarms related to the upper and lower Spent Fuel Pool Cooling Pools (SFC). Alarms
were also received for high suppression pool water level. Upon further investigation, it
1
The National Earthquake Information Center and the USGS are essentially the same organization and can
be used interchangeably.
A2-2 Attachment
was discovered that an earthquake was experienced near McKinley Park, Alaska at
5:12 PM EST.
The effect of this earthquake at RBS was limited to oscillations on the surface of
holding tanks including the Suppression Pool, the Reactor Cavity/associated pools, and
the Spent Fuel Pool.
The entire plant was walked down with particular attention being paid to Safety-Related
systems. No abnormalities were found. The Seismic Monitoring System recorders did
not start and no 'Seismic' alarms were received in the Main Control Room; therefore,
the magnitude of this event was far less than the River Bend Operating Basis
Earthquake (OBE) and Safe Shutdown Earthquake (SSE). Based on the plant walk
down, absence of alarms, the Operability of plant equipment was not impacted by this
condition and no EAL was determined to require entry.
Other examples of appropriate operator response to seismic monitoring/events
demonstrate expected behavior; for example, Condition Report 2004-1630 details an
instance when Alarm Number 567, SEISMIC EVENT HIGH/HIGH was received.
Operators performed alarm response procedure actions (ARP), called the duty
Engineering Supervisor, and contacted the seismic lab at the National Earthquake
Information Center and verified that no seismic activity was recorded at St. Francisville,
RBS concedes that the time to classify a seismic event may in some instances take
longer; however given the type of event, station procedures (ARPs, EIPs), available
seismic instrumentation, physical cues and National Earthquake Information Center
resources, the station would effectively implement appropriate EALs.
Position
The River Bend Station Emergency Plan and the implementing procedures were
approved by the NRC and all subsequent changes have received appropriate reviews
as required by regulations.
Subsection 50.47(b)(4) and Appendix E of 10 CFR Part 50 require licensees to develop
an emergency classification scheme whose purpose is to initiate a minimum set of
onsite and offsite emergency response actions commensurate with existing plant
conditions and the trend of those conditions. RBS has developed and implemented this
scheme.
Subsection 50.54(q) of 10 CFR Part 50 requires licensees to follow and maintain their
emergency plans which meet the standards in 50.47(b) and the requirements of
Appendix E. Thus, licensees are required to classify emergencies in accordance with
their approved emergency classification schemes.
A2-3 Attachment
RBS has implemented its Emergency Plan requirements relative to EALs in Emergency
Implementing Procedures (EIPs). EIP-2-001, Classification of Emergencies, contains
guidance for the Emergency Director to use if available primary instrumentation is out of
service. Specifically, Section 5.3 states:
For Emergency Action Levels based on plant instrumentation, the indication
shall be a valid indication. When all indications for a certain parameter have
been lost, the Emergency Director should use his best judgment and other plant
indications to classify the emergency (e.g., loss of level trend on all RPV level
instrumentation).
RBS recognizes that the declaration may be more complicated due to out of service
seismic instruments; however, the requirement to declare EALs ultimately will be
satisfied2. Below is an excerpt from NRC position3 stating clearly that the NRC staff
recognizes that no explicit regulatory requirement exists related to time to classify an
event and that availability of indications will start the time clock to classification:
Although the regulations do not provide an explicit time limit for classifying
emergencies, they do imply that classification should be made without delay. The
ultimate goal of the classification scheme is to ensure that emergency response
personnel and equipment are already in place if it becomes necessary to
implement actions to protect the public health and safety. Therefore, if
classification is not made promptly, following the availability of indications that an
emergency condition exists, the goal of the classification scheme is undermined
and the intent of the regulations would not be met.
The events in question (OBE and SSE) are of such a nature that instrumentation
would not be the only means to determine that a seismic event requiring
classification has occurred. The .05 g (OBE) event will be felt in the Main
Control Room, as will the .10 g (SSE) event. This is sufficient to trigger the
Operations Shift Manager (OSM) to pursue classification of the event even if the
instrumentation is out of service. This method of classification is recognized
within the more recent regulatory guidance provided to licensees as an
acceptable alternative4.
In the event the magnitude cannot be exactly determined, the EIP directs the
Emergency Director (ED) to use his best judgment in making an EAL determination. It
is reasonable to assume that the Alarm Response Procedures (ARP), physical
2
NRCs position is that no specific time requirement exists to classify an event only that when indications
are available the event will be classified (generally within 15 minutes of access to indications).
3
EPPOS No. 2 dated August 1, 1995, Emergency Preparedness Position (EPPOS) on Timeliness of
Classification of Emergency Conditions.
4
Reg Guide 1.166, March 1997, Provides in Appendix A that it is acceptable to use felt indicators backed
by National Earthquake Information Center data.
A2-4 Attachment
indicators (felt motion, suppression pool wavelets, etc.) and training5 would be used to
estimate the size of the earthquake and an EAL selected.
The current Alarm Response Procedure provides information which will allow the OSM
to contact the Earthquake Center to assist in determining the magnitude of the event
(recognized in the license basis as off-site resources), at the site. The Center can
provide this information for the site in the form of a magnitude. Guidance exists in the
System Training Manual as to the comparison of the magnitude of an earthquake and
its associated range of ground acceleration values. Assistance from Engineering or
other sources could also be obtained to assess and classify the event.
Using newer NRC and industry guidance6, it is reasonable to conclude that the exact
magnitude of the event is not as important initially as the fact that an event did occur.
NRC has endorsed this new guidance that would expect actual determination of an
OBE to take up to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> or more. Therefore, this condition alone should not
constitute the inability to declare an EAL.
River Bend Station has implemented the Required Actions of TR 3.3.7.5 and is in full
compliance with its requirements. Historical NRC policies recognize that licensees will
take seismic monitoring equipment out of service in accordance with their license bases
and this is acceptable.
NRC Emergency Preparedness Position (EPPOS) on acceptable deviations from
Appendix 1 of NUREG-0654 based upon the staffs regulatory analysis of
NUMARC/NESP-007, Methodology for Development of Emergency Action Levels,
allows, among other things, the deletion of a NOUE classification for loss of seismic
instrumentation. The basis is that: Standard technical specifications allow a plants
seismic monitoring system to be out of service for days. In addition, loss of this
instrumentation does not represent a significant loss of assessment capability. These
statements link the out of service time for the seismic monitoring system used for EAL
determination, to the requirements of the current TRM section on seismic instruments
(formerly part of the Technical Specifications).
In view of the presented information, we believe that no regulatory basis exists for
issuance of a violation for this equipment having been out of service as allowed by the
Required Action time of TR 3.3.7.5. The NRC EPPOS establishes that the basis for
seismic monitoring instrumentation allowed outage time is the TRM as implemented by
RBS. Therefore, RBS does not believe that this would constitute a violation with a
significance of greater than green.
Regulatory Bases
5
RBS System Training Manual provides instruction on how to classify seismic events given various
common measures of magnitude. Operators have been trained on this activity and the information is
readily available.
6
Regulatory Guide 1.166 dated 1997
A2-5 Attachment
EAL BASIS
Federal Regulations dictate that River Bend Station must develop and implement an
Key regulatory requirements are provided below:
q 10CFR50.54 (q) A licensee authorized to possess and operate a nuclear power
reactor shall follow and maintain in effect emergency plans which meet the
standards in § 50.47(b) and the requirements in appendix E of this part [...]
q 10CFR50.47 (b) (4) A standard emergency classification and action level
scheme, the bases of which include facility system and effluent parameters, is in
use by the nuclear facility licensee, and State and local response plans call for
reliance on information provided by facility licensees for determinations of
minimum initial offsite response measures.
RBS responded to specific questions from NRC during their review of the stations
Emergency Plan (then a part of the SAR).
The station has implemented its Emergency Plan requirements relative to EALs in
Emergency Implementing Procedures (EIPs). EIP-2-001, Classification of
Emergencies, contains guidance for use by the Emergency Director if available primary
instrumentation is out of service. Specifically, Section 5.3 states
For Emergency Action Levels based on plant instrumentation, the indication
shall be a valid indication. When all indications for a certain parameter have
been lost, the Emergency Director should use his best judgment and other plant
indications to classify the emergency (e.g., loss of level trend on all RPV level
instrumentation).
Seismic Monitoring Basis
During initial licensing activities, NRC reviewed and approved the seismic monitoring
instruments at RBS. The depth of this review is evidenced by the questions and
answers some of which are provided below for demonstrative value.
River Bend Station FSAR Amendment 8 Question 810.32:
The plan does not adequately describe [] Geophysical phenomena monitors
(h.5.a) [] referred to in Section 13.3.6.3.1
Response:
A2-6 Attachment
The response to this request is provided in revised Section 13.3.6.3.1.
Section 13.3.6.3.1, The seismic instrumentation at the station is utilized to
monitor and record [] complies with Regulatory Guide 1.12. []
Changes made were also included on Amendment 8, Table 13.3-8 listing the
monitors and their applicability.
River Bend Station FSAR Amendment 8 Question 810.33:
The capability to acquire or have access to offsite seismic and hydrological data
is not addressed. (H.6.a)
Response:
Seismic and hydrological data are available to GSU through the offices of the
U.S. Army Corps of Engineers in New Orleans, Louisiana and the U. S.
Geological Survey7 in Baton Rouge, Louisiana.
Allowed Outage Time as Applied to Seismic Monitoring
In Regulatory Guide 1.12, Revision 1, NRC provides a position requiring seismic
monitoring instrumentation. NRC goes on to state that Paragraph (c) of 10 CFR 50.36,
Technical Specifications, requires that the technical specifications include surveillance
requirements to assure that the necessary quality of systems and components is
maintained, that the facility operations will be within safety limits and that the limiting
conditions for operations (LCO) will be met. The 10 CFR Part 100, Appendix A,
Seismic and Geological Siting Criteria for Nuclear Power Plants, also describes the
instrumentation acceptable to the Regulatory Staff. This scheme was implemented and
approved by NRC at RBS8.
Upon NRC approval, RBS implemented the Technical Specification 3.3.7.2, Seismic
Monitoring Instrumentation. An excerpt is below:
Limiting Condition for Operation
3.3.7.2 - The Seismic monitoring instrumentation shown in Table 3.3.7.2-1 shall
be operable.
ACTION:
a. With one or more of the above required seismic monitoring instruments
7
USGS and National Earthquake Information Center are used interchangeably.
8
RBS USAR Section 3.7.4.1A states that seismic monitoring instrumentation complies with RG 1.12.
A2-7 Attachment
inoperable for more than 30 days, prepare and submit within the next 10 days a
Special Report to the Commission, pursuant to Specification 6.9.2, outlining the
cause of the malfunction and the plans for restoring the instrument(s) to
OPERABLE status.
With implementation of Improved Technical Specifications, the station relocated the
seismic monitoring requirements to the Technical Requirements Manual (TRM) with a
License Amendment Request (LAR). Below is the relocated specification discussion
approved by NRC9:
R.1 The seismic monitoring instrumentation provides information only and is not
considered in any design basis accident or transient. It does provide information
regarding the severity of an earthquake; however, the evaluation summarized in
NEDO-31466 determined the loss of this instrumentation to be a non-significant
risk contributor to core damage frequency and off-site release. Therefore, the
requirements specified for this function did not satisfy the NRC Interim Policy
Statement technical specification screening criteria as documented in the
Application of Selection Criteria to the RBS TS and have been relocated to plant
documents controlled in accordance with 10 CFR 50.59.
Given the Action Statement of the TS (now TRM), RBS has 30 days to perform
maintenance or otherwise take out of service the seismic monitors. Additionally, the
requirements allow separate entry for each channel. The TRM10 does not provide any
specified actions to be taken while an instrument is out of service.
Absent any specific regulatory guidance contained within the TRM, RBS reviewed
applicable NRC positions.
q In EPPOS No. 111, NRC prepared a position providing guidance to the staff on
the acceptability of proposed emergency action level (EAL) revisions when those
revisions depart from the guidance in Appendix 1 of NUREG-0654.
Unusual Event #11 ...significant loss of assessment...all meteorological
instrumentation
Basis: Due to the shift in emphasis from classification based upon dose
assessment to classification based upon plant conditions [] For licensees who
have incorporated the loss of seismic monitoring instrumentation as an Unusual
9
The relocation essentially moved the requirements from the Technical Specifications to the Technical
Requirements Manual unchanged.
10
RBS USAR Section 3.7.4A states that surveillance requirements for seismic instrumentation are listed
and controlled by the RBS Technical Requirements Manual (TRM).
11
EPPOS Number 1, dated June 1, 1995, This paper provides examples of some of the acceptable
changes that licensees may make based upon the staffs current understanding of the thresholds of the four
emergency classes.
A2-8 Attachment
Event, this EAL may also be eliminated. Standard technical specifications allow a
plants seismic monitoring system to be out of service for days. In addition, loss
of this instrumentation does not represent a significant loss of assessment
capability.
q Regulatory Guide 1.12, Revision 2,12 Nuclear Power Plant Instrumentation for
Earthquakes, dated March 1997, provides an additional data point that
demonstrates NRCs recognition that seismic monitors may be out of service.
SEE below:
An NRC staff evaluation of seismic instrumentation noted that instruments have
been out of service during plant shutdown and sometimes during plant operation
[] If the seismic instrumentation or data processing hardware and software
necessary to determine whether the OBE has been exceeded is inoperable, the
guidelines in Appendix A to Regulatory Guide 1.166 should be used []
Regulatory Guide 1.166, March 1997 states in Section 4.4:
Inoperable Instrumentation or Data Processing Hardware or Software
If the response spectrum and the CAV (Regulatory Positions 4.1 and 4.2) cannot
be obtained because the seismic instrumentation is inoperable, data from the
instrumentation are destroyed, or the data processing hardware or software is
inoperable, the criteria in Appendix A to this guide should be used to determine
whether the OBE has been exceeded.
Regulatory Guide 1.166, March 1997, Appendix A:
For plants at which no free-field or foundation-level instrumental data are
available, or the data processing equipment is inoperable [] the OBE will be
considered to have been exceeded and the plant must be shut down if one of the
following applies:
1. The earthquake resulted in Modified Mercalli Intensity13 (MMI) VI or greater
within 5 km of the plant,
2. The earthquake was felt within the plant and was of magnitude 6.0 or greater,
or
3. The earthquake was of magnitude 5.0 or greater and occurred within 200 km
of the plant.
A post earthquake plant walkdown should be conducted after the earthquake.
12
RBS is not committed to this revision; however, this example clearly supports that NRC understands that
seismic monitors are at times out of service for various reasons; one of which would be per the TRM.
13
Modified Mercalli Intensity is based upon subjective criteria that are non-scientific; for example: people
awakening, furniture moving, damage to chimneys, etc. The data is gathered post-earthquake and
tabulated. The epicenter is where the observed intensity generally occurs (USGS sourced information).
A2-9 Attachment
Note: The determinations of epicenter location, magnitude, and intensity by the
U.S. Geological Survey, National Earthquake Information Center, will usually
take precedence over other estimates; however, regional and local
determinations will be used if they are considered to be more accurate. Also,
higher quality damage reports or a lack of damage reports from the nuclear
power plant site or its immediate vicinity will take precedence over more distant
reports.
RBS believes that these referenced NRC positions are taken with the knowledge that
the allowed outage time for the seismic monitoring system used for EAL determination,
would be subject to the requirements of a licensees (RBS) TS or TRM. This then
establishes the TRM as the basis for allowed outage time.
Complying with TLCO 3.3.7.5, Condition A, Required Action A.1, instruments can be
out of service for up to 30 days (each channel). Should the need to exceed 30 days
arise, an appropriate action to be taken would be the initiation of a corrective action
document (CR).
Conclusion
RBS is confident that operators would implement existing site procedures (ARPs, EIPs,
STPs), evaluate available seismic instruments, be sensitive to physical parameters (felt
motion, tanks levels, pool level, etc.), request site engineering assistance, and call upon
offsite seismology resources enabling the station to determine the magnitude of an
event and permit classification.
Additionally, RBS believes that the stations past performance serves as validation that
using existing Alarm Response Procedures, TRM TLCO status (shift briefings), and
felt physical indicators of a seismic event, that appropriate actions will be taken to
protect the plant as well as the health and safety of the public. In 2002, operations
demonstrated that when suspected seismic events have occurred, they have called the
offsite seismic labs for validation14, initiated condition reports and have conducted
appropriate investigations to ensure plant and public safety.
14
CR 2002-1723 - This Condition regards the effects felt at River Band Station from a Magnitude 7.9
earthquake near McKinley Park, Alaska. The effect of this earthquake at RBS was limited to oscillations on
the surface of holding tanks including the Suppression Pool, the Reactor Cavity and associated pools, and
the Spent Fuel Pool. The entire plant has been walked down, paying particular attention to all Safety-
Related systems. No abnormalities have been found. The Seismic Monitoring System did not start and no
'Seismic' alarms were received in the Main Control Room; therefore, the magnitude of this event was far
less than the River Bend Operating Basis Earthquake and Safe Shutdown Earthquake. Based on the plant
walk down, absence of alarms, the Operability of plant equipment is not indicted by this condition.
A2-10 Attachment