ML051670575
ML051670575 | |
Person / Time | |
---|---|
Site: | Crystal River ![]() |
Issue date: | 06/16/2005 |
From: | Mccree V Division of Reactor Safety II |
To: | Young D Florida Power Corp |
References | |
EA-05-114, IR-04-009 IR-05-007 | |
Download: ML051670575 (13) | |
See also: IR 05000302/2005007
Text
June 16, 2005
Mr. Dale E. Young, Vice President
Crystal River Nuclear Plant (NA1B)
ATTN: Supervisor, Licensing &
Regulatory Programs
15760 West Power Line Street
Crystal River, FL 34428-6708
SUBJECT: CRYSTAL RIVER UNIT 3 - NRC TRIENNIAL FIRE PROTECTION INSPECTION
(FOLLOW UP) REPORT NO. 05000302/2005007; PRELIMINARY GREATER
THAN GREEN FINDING
Dear Mr. Young:
On June 8, 2005, the U.S. Nuclear Regulatory Commission (NRC) completed an in-office
examination of an unresolved item (URI) associated with the Crystal River 3 facility which was
identified in NRC Inspection Report 05000302/2004009 (ADAMS Accession Number
ML050740113) forwarded to you on March 14, 2005. Specifically, URI 05000302/2004009-01,
Unprotected Post-Fire Safe Shutdown Cables and Related Non-feasible Local Manual Operator
Action, was identified as unresolved pending completion of a significance determination. The
finding, as indicated by the enclosed supporting documentation, appears to be of greater than
very low safety significance (GREEN). The finding and the preliminary significance
determination were discussed on June 16, 2005, with you and other members of your staff.
As discussed in NRC Inspection Report 05000302/2004009, a fire in the 3A 4160V engineered
safeguards (ES) compartment could result in a total loss of offsite power. In addition fire
damage to the metering and protection electrical cables located in or just above the 3A 4160V
ES switchgear could trip and lock out all feeder breakers to both 4160V ES busses causing a
loss of all safety-related A.C. power. These protection and metering circuits were not physically
separated or protected from fire damage as required by 10 CFR 50, Appendix R, Section
III.G.2. Instead an unapproved local manual operator action was used to restore A.C. power.
However, this local manual operator action to reset the 3B emergency diesel generator breaker
lockout on the 3B 4160V ES switchgear was not feasible.
This finding was assessed based on the best available information, including influential
assumptions, using the applicable Significance Determination Process (SDP). The finding was
preliminarily determined to be Greater than Green. The finding has a greater than very low
safety significance because it could affect fire protection defense in depth. In addition,
uncertainties associated with identifying all the fire scenarios that can impact the metering and
protection circuitry, the primary plant response to a delay in secondary side heat removal, the
effectiveness of secondary side heat removal systems following an overcooling event, and
FPC 2
operator response to these fires contribute to the preliminarily characterization of the finding as
greater than green. This issue was also determined to be an apparent violation of NRC
requirements, as discussed in the Enclosure. However, the finding does not represent a
current safety concern because you have modified and corrected the nonconforming condition
before the inspection team left the site.
Our SDP Phase 2 evaluation of this finding is provided in Attachment 2. Additional information
from Progress Energy Florida (Florida Power Corporation) that addresses the assumptions in
our evaluation will permit a more refined risk analysis.
Before we make 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. 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 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.
This apparent violation is being considered for escalated enforcement action in accordance with
the Enforcement Policy, because it is associated with a greater than Green finding. The current
Enforcement Policy is included on the NRCs Web site at http://www.nrc.gov/reading-
rm/adams.html
Please contact Mr. D. Charles Payne at (404) 562-4669 within seven days of the date of this
letter to notify the NRC of your intentions regarding the regulatory conference for the
preliminary Greater than Green finding. If we have not heard from you within 10 days, we will
continue with our significance determination and associated enforcement processes on this
finding, 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 number
and characterization of the apparent violation described in the referenced inspection report may
change as a result of further NRC review. For administrative purposes, this letter is issued as a
separate NRC Inspection Report, No. 05000302/2005007, and the above apparent violation is
identified as AV 0500302/2005007-01, Unprotected Post-Fire Safe Shutdown Cables and
Related Non-feasible Local Manual Operator Action. Accordingly, URI 05000302/2004009-01
is closed.
In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter,
portions of its enclosure and your response (if any) will be available electronically for public
inspection in the NRC Public Document Room or from the Publicly Available Records (PARS)
component of NRCs document system (ADAMS). However, the NRC is continuing to review
the appropriate classification of the SDP Phase 2 Evaluation (Attachment 2) within our records
management program, considering changes in our practices following the events of September
FPC 3
11, 2001. Using our interim guidance, the attached analyses have been marked as Proprietary
Information or Sensitive Information in accordance with Section 2.390(d) of Title 10 of the Code
of Federal Regulations and will not be placed in the PDR. Please control the document
accordingly (i.e., treat the document as if you had determined that it contained trade secrets
and commercial or financial information that you considered privileged or confidential). We will
inform you if the classification of these documents change as a result of our ongoing
assessments. ADAMS is accessible from the NRC web site at http://www.nrc.gov/reading-
rm/adams.html (the Public Electronic Reading Room).
If you have any questions regarding this letter, please contact me at 404-562-4600.
Sincerely,
\\RA\\
Victor M. McCree, Director
Division of Reactor Safety
Docket No.: 50-302
License No.: DPR-72
Enclosure: Inspection Report 05000302/2005007
w/Attachments: 1. Supplemental Information
cc w/encl:
Daniel L. Roderick
Director Site Operations
Crystal River Nuclear Plant (NA2C)
Electronic Mail Distribution
Jon A. Franke
Plant General Manager
Crystal River Nuclear Plant (NA2C)
Electronic Mail Distribution
Richard L. Warden
Manager Nuclear Assessment
Crystal River Nuclear Plant (NA2C)
Electronic Mail Distribution
cc w/encl contd - (See page 4)
FPC 4
cc w/encl:
Michael J. Annacone
Engineering Manager
Crystal River Nuclear Plant (NA2C)
Electronic Mail Distribution
R. Alexander Glenn
Associate General Counsel (MAC - BT15A)
Florida Power Corporation
Electronic Mail Distribution
Steven R. Carr
Associate General Counsel - Legal Dept.
Progress Energy Service Company, LLC
Electronic Mail Distribution
Attorney General
Department of Legal Affairs
The Capitol
Tallahassee, FL 32304
William A. Passetti
Bureau of Radiation Control
Department of Health
Electronic Mail Distribution
Craig Fugate, Director
Division of Emergency Preparedness
Department of Community Affairs
Electronic Mail Distribution
Chairman
Board of County Commissioners
Citrus County
110 N. Apopka Avenue
Inverness, FL 36250
Jim Mallay
Framatome Technologies
Electronic Mail Distribution
_________________________
OFFICE RII:DRS RII:DRS RII:DRP* RII:OI
SIGNATURE WGR1 DCP JTM CFE
NAME WRogers DPayne JMunday CEvans
DATE 6/14/2005 6/14/2005 6/13/2005 6/16/2005 6/ /2005 6/ /2005 6/ /2005
E-MAIL COPY? YES NO YES NO YES NO YES NO YES NO YES NO YES NO
U. S. NUCLEAR REGULATORY COMMISSION
REGION II
Docket No.: 50-302
License No.: DPR-72
Report No.: 05000302/2005007
Licensee: Progress Energy Florida (Florida Power Corporation)
Facility: Crystal River Unit 3
Location: 15760 West Power Line Street
Crystal River, FL 34428-6708
Dates: January 28, 2005 - June 16, 2005
Inspectors: R. Rodriguez, Reactor Inspector
R. Schin, Senior Reactor Inspector (Lead Inspector)
W. Rogers, Senior Reactor Analyst
Approved by: D. Charles Payne, Chief, Engineering Branch 2
Division of Reactor Safety
SUMMARY OF FINDINGS
IR 05000302/2005007; Crystal River Nuclear Plant, Unit 3; Significance Determination of
Unresolved Item from Triennial Fire Protection Inspection.
This in-office review was conducted by two regional inspectors and a senior reactor analyst.
One preliminary Greater than Green finding with an apparent violation was identified. The
significance of most findings is indicated by their color (Green, White, Yellow, Red) using IMC 0609 Significance Determination Process (SDP). Findings for which the SDP does not apply
may be Green or be assigned a severity level after NRC management review. 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: Initiating Events and Mitigating Systems
- Preliminary Greater than Green. An apparent violation of 10 CFR 50, Appendix
R,Section III.G.2, for failure to physically protect or separate cables from fire
damage and instead relying on an unapproved local manual operator action.
The unprotected cables were associated with a common electrical protection and
metering circuit which was installed such that fire damage to a cable in or just
above the 3A 4160V engineered safeguards (ES) switchgear could result in
tripping and locking out all feeder breakers to both 4160V ES busses, resulting in
a loss of all safety-related alternating current power.
In addition, the local manual operator action to reset the 3B emergency diesel
generator breaker lockout on the 3B 4160V ES switchgear was determined to be
non-feasible. During a severe fire in the adjacent 3A 4160V Switchgear Room
the fire response activities would cause the location for the operator action (the
3B 4160V Switchgear Room) to be exposed to hot smoke, water mist, and water
on the floor.
This finding is greater than minor because it degraded the defense in depth for
fire protection and also because it is associated with the protection against
external factors attribute and degraded the reactor safety mitigating systems
cornerstone objective. The finding adversely affected the reliability and
capability of equipment required to achieve and maintain a safe shutdown
condition following a severe fire in the 3A 4160V ES Switchgear Room.
(Section 4OA5.01)
B. Licensee-identified Violations:
None
Report Details
4. OTHER ACTIVITIES
4OA5 OTHER
.1 (Closed) URI 05000302/2004009-01. Unprotected Post-Fire Safe Shutdown Cables and
Related Non-feasible Local Manual Operator Action.
Introduction. An apparent violation (AV) of 10 CFR 50, Appendix R, Section III.G.2, for
failure to physically protect or separate cables from fire damage and instead relying on a
local manual operator action that was not approved by the NRC. The unprotected
cables were in common electrical protection and metering circuits which were installed
such that fire damage to a cable in or just above the 3A 4160V ES switchgear could trip
and lock out all feeder breakers to both 4160V ES busses, resulting in a loss of all
safety-related alternating current (a.c.) power.
In addition, the team found that the licensees local manual operator action to mitigate
this condition was not feasible. The action was to reset the 3B emergency diesel
generator (EDG) breaker lockout on the 3B 4160V ES switchgear. However, that action
was not feasible because the fire in the 3A 4160V Switchgear Room and fire fighting
activities through the adjacent 3B 4160V Switchgear Room would cause the location for
the operator action (in the 3B 4160V Switchgear Room) to be exposed to hot smoke,
water mist, and water on the floor. This inspection finding was assessed using the SDP
and preliminarily determined to be Greater than Green (i.e., an issue with low to
moderate increased importance to safety, which may require additional NRC
inspections.)
Description. During the baseline triennial fire protection inspection, the inspectors
identified a finding involving cables for the electrical protection and metering circuit
located in the 3A 4160V ES Switchgear Room were vulnerable to fire damage that could
disable both the 3A 4160V ES switchgear and the redundant train 3B 4160V ES
switchgear, having potential safety significance greater than very low significance.
Specifically, the licensees 10 CFR 50 Appendix R Fire Study and post-fire safe
shutdown (SSD) procedure OP-880A, Appendix R Post-Fire Safe Shutdown
Information, Rev. 5, Step 9-6, included a local manual operator action that was not
approved by the NRC and also was not feasible. The action was to reset the 3B EDG
breaker lockout on the 3B 4160V ES switchgear during a fire in the 3A 4160V ES
Switchgear Room. This action was time critical and required to be completed within 30
minutes of entering OP-880A. Operators were to trip the reactor and enter OP-880A if a
fire in the 3A 4160V Switchgear Room impacted safe operation of the plant. The
licensee had considered that the action was needed because a fire in the 3A 4160V ES
switchgear could affect cables for the electrical protection and metering circuit and could
lock out all feeder breakers to both the 3A and the 3B 4160V ES switchgear. However,
the licensees post-fire SSD methodology relied upon equipment powered from the 3B
4160V ES switchgear. Specifically, the licensees analysis determined that power to the
3B 4160V switchgear was needed within 30 minutes to enable operators to restore
2
ventilation cooling to the Emergency Feedwater Initiation and Control (EFIC) rooms.
The EFIC system was needed for automatic EFW flow control.
The team found that cables for the electrical protection and metering circuit were
located within and directly above the 3A 4160V switchgear, where a fire originating in
certain sections of the switchgear could immediately damage them. The team noted
that these cables were four-conductor, #8 American Wire Gage (AWG), Institute of
Institute of Electrical and Electronic Engineers (IEEE) 383 qualified, thermoset-type
cables with no protective fire wrap. Damage to one of these cables could result in
immediate loss of both the 3A and the 3B 4160V ES switchgear, and a loss of all safety-
related a.c. power. Plant operators would conclude this had an impact on safe
operation of the plant, would trip the reactor, and immediately enter OP-880.
During this fire condition, the primary plant operator (PPO) had a number of
proceduralized time-critical local manual operator actions to perform in a prescribed
sequence. Based on Pre-fire Plans and fire brigade drill results, the fire brigade would
attack a fire in the 3A 4160V Switchgear Room through the 3B 4160V Switchgear Room
about 15 minutes after confirmation of the fire. Based on licensee time validations and
NRC team walkdowns of the actions, the team determined that the PPO would arrive at
the 3B 4160V Switchgear Room about 25 minutes into the fire event. When the PPO
arrived, the fire brigade would have the door between the two switchgear rooms open
and would have sprayed fire water into the 3A 4160V Switchgear Room. Hot smoke
from the fire would have filled both the 3A and 3B 4160V ES switchgear rooms and the
hallway leading to those rooms because the fire brigade would have all doorways
between the two rooms and the hallway blocked open with their fire hose. In addition,
water from the fire hose would have created mist in the air and water on the floors of
both switchgear rooms (the switchgear rooms had no floor drains). At 25 minutes into
the fire event, the fire brigade would not yet have had time to evacuate the smoke with
portable fans. In addition, the portable fans would not have electrical power available
because the outlets for the fans were powered from the 3A and 3B 4160V switchgear,
which would potentially be de-energized. While the fire brigade could obtain a portable
generator to power the fans, this would take too long to allow the operator to complete
the action within the time-critical 30 minutes. In view of all of these conditions, the team
concluded that the operator action was not feasible.
This finding was an immediate safety concern and the licensee made modifications to
correct the nonconforming condition before the inspection team left the site.
Analysis: This finding degraded the defense in depth for fire protection and also it is
associated with the protection against external factors attribute and degraded the
reactor safety mitigating systems cornerstone objective. The finding adversely affected
the reliability and capability of equipment required to achieve and maintain a SSD
condition following a severe fire. The finding is applicable to post-fire SSD from the
control room during a fire in the 3A 4160V ES Switchgear Room. Because the finding
affects fire protection, it was assessed in accordance with the NRC Reactor Oversight
Processs SDP as described in NRC Inspection Manual Chapter 0609, Appendix F (MC 0609, App. F). In the Phase 1, the finding was associated with post-fire safe shutdown,
3
it was assigned a high degradation rating and it existed for more than 30 days. As a
result, a Phase 2 Risk Evaluation was required.
Summary of Phase 2 SDP Analysis
This evaluation was performed by Region II inspectors with the assistance of the
regional SRA. The Crystal River Phase 2 SDP Analysis is included in this inspection
report as Attachment 2.
The Phase 2 analysis involves a quantitative assessment of CDF increase given a
finding. There are nine analysis steps and five screening checks. This assessment
includes quantification of a Fire Frequency, Fire Damage State, Non-Suppression
Probability and Conditional Core Damage Probability (CCDP). The report also contains
several appendices documenting supplemental information used in the Phase 2
analysis.
Effects from a fire in the 3A 4160V switchgear room were postulated and evaluated. Not
all ignition sources were counted in the fire area, only the cabinets where the CT
circuitry is located were considered. The room has no automatic suppression and no
manual suppression credit is applied with the target damaged within 1 minute. This
yielded an Fire Frequency of 2.4E-04.
A loss of offsite power and a plant trip were postulated and the appropriate plant
initiating event worksheet from the plant risk-informed inspection notebook was used to
account for the plant SSD response and required human recovery actions in order to
quantify the factor CCDP for each fire scenario of interest.
The Phase 2 analysis concluded that the change in Core Damage Frequency ( CDF)
[the difference between the conforming case CDF and the non-conforming case CDF]
was 2.4E-05 (substantial importance to safety).
SDP/Enforcement Review Panel (SERP) Evaluation
The total change in CDF due to the performance deficiency was found to be 2.4 E-05/yr
for the unit. The dominant accident sequences that cause the largest CDF are fully
developed fires that require Emergency AC Power and Emergency Feedwater. The
color associated with this magnitude of change in CDF is Greater than Green.
Therefore, the SERP has preliminarily determined this issue to be a Greater than Green
finding.
4
Enforcement: 10 CFR 50.48(b)(1) requires, in part, that all nuclear power plants
licensed to operate prior to January 1, 1979, must satisfy the applicable requirements of
Appendix R,Section III.G.Section III.G.2 applies to the ability to achieve and maintain
hot SSD from the control room during a fire. It states, in part, that where cables or
equipment, including associated non-safety circuits that could prevent operation or
cause maloperation due to hot shorts, open circuits, or shorts to ground, of redundant
trains of systems necessary to achieve and maintain hot shutdown conditions are
located within the same fire area outside of primary containment, one of three means of
protecting cables to ensure that one of the redundant trains is free of fire damage shall
be provided. The three means include, among others, the physical protection or
separation of cables to preclude fire damage.
Contrary to the above, on January 26, 2005, cables for the electrical protection and
metering circuit located in the 3A 4160V ES Switchgear Room were vulnerable to fire
damage that could disable both the 3A 4160V ES switchgear and the redundant train 3B
4160V ES switchgear. Specifically, these protection and metering circuits were not
physically separated or protected (as discussed above) from fire damage as required by
10 CFR 50, Appendix R, Section III.G.2. This apparent violation is identified as AV
05000302 /2005007-01, Unprotected Post-Fire Safe Shutdown Cables and Related
Non-feasible Local Manual Operator Action. Accordingly, URI 05000302/2004009-01 is
closed.
4OA6 Meetings, Including Exit
On June 16, 2005, the inspectors presented the inspection results by telephone to
Mr. Dale E. Young and other members of your staff, who acknowledged the findings.
The inspectors confirmed that proprietary information was not provided or examined
during the inspection.
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee personnel
NRC personnel
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
Opened
05000302/2005007-01 AV Unprotected Post-Fire Safe Shutdown Cables and
Related Non-feasible Local Manual Operator Action
(Section 4OA5.1)
Closed
05000302/2004009-01 URI Unprotected Post-Fire Safe Shutdown Cables and
Related Non-feasible Local Manual Operator Action
(Section 4OA5.1)
LIST OF DOCUMENTS REVIEWED
Procedures:
OP-880A, Appendix R Post-Fire Safe Shutdown Information, Rev. 5
Drawings:
E-215-031, Electrical Conduit Layout Control Complex, Rev. 56
Attachment 1
2
Other Documents:
10CFR50 Appendix R Fire Study, Rev. 12
Licensee Event Report 50-302/2005-001, Design Change Create Engineered Safeguards Bus
Protective Relay Scheme Single Failure Vulnerability, dated March 23, 2005
NRC Information Notice 2005-04: Single-failure and Fire Vulnerability of Redundant Electrical
Safety Buses, dated February 14, 2005
LIST OF ACRONYMS
AV Apparent Violation
AWG American Wire Gage
CCDP Conditional Core Damage Probability
CDF Core Damage Frequency
CFR Code of Federal Regulations
CR Condition Report
EDG Emergency Diesel Generator
EFIC Emergency Feedwater Initiation and Control
ES Engineered Safeguards
IEEE Institute of Institute of Electrical and Electronic Engineers
IEL Initiating Event Likelihood
MCR Main Control Room
No. Number
NRC U.S. Nuclear Regulatory Commission
PARS Publicly Available Records System
PPO Primary Plant Operator
SBO Station Blackout
SDP Significance Determination Process
SERP SDP/Enforcement Review Panel
SSD Safe Shutdown
URI Unresolved Item
VIO Violation
Attachment 1