ML20198L362
| ML20198L362 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 12/12/1998 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20198L349 | List: |
| References | |
| 50-317-98-10, 50-318-98-10, NUDOCS 9901040176 | |
| Download: ML20198L362 (34) | |
See also: IR 05000317/1998010
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U. S. NUCLEAR REGULATORY COMMISSION
REGION 1
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Docket Nos:
50-317/50-318
License Nos:
DPR-53/DPR-69
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-Report Nos:
50-317/98-10,50-318/98-10
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Licensee:
Baltimore Gas and Electric Company (BG&E)
Post Office Box 1475
Baltimore, Maryland 21203
Facility:
Calvert Cliffs Nuclear Power Plant
Unit 1 and Unit 2
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Location:
Lusby, Maryland
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Dates:
July 6 - 10,1998 & November 18,1998
Inspector:
Keith A. Young, Reactor Engineer
- Approved by:
David C. Lew, Chief
Electrical Engineering Branch
Division of Reactor Safety
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9901040176 981212
ADOCK 05000317
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EXECUTIVE SUMMARY
Calvert Cliffs Nuclear Power Plant, Units 1 and 2
Inspection Report No. 50-317,318/98-10
This inspection included aspects of licensee plant support with emphasis on the 10 CFR 50, Appendix R program. The report covers a five-day announced onsite inspection
conducted by a regional engineering inspector. Additional in-office review was also
conducted by a regional engineering inspector.
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Plant Suooort
. The licensee's Appendix R program self-assessment was of good qualit'.' and was effective
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in identifying non-compliances and areas for improvement, in response to these findings,
the licensee implemented effective corrective actions, including plant modifications to
motor-operated valve circuits and Appendix R hand switches, and enhancements to
. abnormal operating procedures (AOPs). Appropriate compensatory actions were taken for
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required changes that were planned, but not yet completed. Additional analyses to review
all cable to cable hot shorts, which could affect the ability of the plant to reach safe
shutdown, was a good initiative. The completion schedule for resolution for identified
issues was appropriate. Resolution of the seven issues outlined in the October 22,1998,
letter to BG&E were adequate. The licensee's Appendix R self assessment identified five
non-compliances. These licensee identified and corrected violations were dispositioned as
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non-cited. (NCV 50-317,318/98-10-01 through 98-10-05) (Section F8.1)
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Report Details
IV. Plant Suonort
Backaround
The purpose of this inspection was to review two open unresolved items and the licensee's
actions in response to a Notice of Violation (NOV). The inspector reviewed actions taken
by BG&E to disposition Appendix R self-assessment findings, and control room and
switchgear room fire protection issues.
F8
-Miscellaneous Fire Protection issues
F8.1
(Closed) Unresolved item 50-317,318/97-08-08: Potential for issues identified
during Appendix R self-assessment to be not in compliance with regulatory
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requirements. The licensee performed a self-assessment of compliance with
Appendix R in response to escalated enforcement relating to switchgear room
ventilation issues identified in 1996. The inspector reviewed 34 specific issues
identified in the Appendix R self-assessment for regulatory compliance, corrective
actions, compensatory actions, and timeliness of schedule completion.
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The inspector found that the licensee had completed comprehensive evaluations for
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most of the 34 issues that were identified in their Appendix R self-assessment.
Some evaluations, such as those for the issue of hot shorts, continue to be
performed with an anticipated completion date scheduled for the Spring of 1999.
Where modifications were determined to be necessary, the licensee completed
modifications for Unit 1 in 1998 and scheduled Unit 2 modifications for completion
during the 1999 refueling outage (RFO). Where plant modifications were not -
completed, adequate compensatory measures were in place.
As part of the disposition of this unresolved item, the inspector reviewed the
licensee's Appendix R self-assessment. During this review, the inspector identified
five issues to be violations of regulatory requirernents. In all cases, the licensee
identified and implemented acceptable corrective actions for these issues.
Discussion of these five issues follow:
Anoendix R Emeraency Liaht Units
The licensee had identified a condition in which safe shutdown Appendix R
emergency lighting was inadequate in the Unit 1 main steam isolation valve (MSIV)
room and in the area of the Unit 2 emergency shutdown panel. The licensee
performed blackout tests and instituted modifications to move or add emergency
lights to those areas. During a walkdown of these areas, the inspector verified that
the licensee moved or added emergency lights appropriately and that the lights
illuminated and provided adequate lighting patterns when the " press to test"
buttons were pushed by licensee personnel.
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This violation of requirements stated in 10 CFR 50, Appendix R, Ill.J, " Emergency
Lighting," is not being cited,'in accordance with Section Vll.B.4 of the General
Statement of Policy and Procedures for NRC Enforcement Actions (Enforcement
Policy) since it was identified by the licensee as part of the corrective action for the
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previous enforcement action, has the same or similar root cause as the violation for
which enforcement action was issued, does not substantially change the safety
significance or character of the regulatory concern arising out of the initial violation
and was or will be corrected, and would not be characterized at a Severity Level 1.
(NCV 50-317,318/98-10-01)
Portable Air Bottles
The licensee identified portable air bottles, used to operate the auxiliary spray valve
(CV-517) to depressurize the reactor coolam <,ystem (RCS) in certain fire scenarios,
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were stored in room 529 where their availability would be in question if a fire
occurred in that room. The air bottles are used to depressurize the RCS tb reach
safe shutdown conditions. The inspector found that the licensee evaluated this
condition and completed an issue report to relocate the air bottles to an appropriate
location (69 ft spent fuel pool exhaust room) where they would be retrievable by
operators to depressurize the reactor coolant system, if a fire occurred in room
No. 529. The inspector verified the new location of the air botties during a walk
down of the spent fuel pool exhaust room. The inspector also found that the
licensee changed the appropriate procedure to reflect the new location of the air
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bottles.
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This violation of requirements stated in 10 CFR 50, Appendix R, Ill.L.3, " Alternate
and Dedicated Shutdown Capability," is not being cited, in accordance with
Section Vll.B.4 of the General Statement of Policy and Procedures for NRC
Enforcement Actions (Enforcement Policy), since it was identified by the licensee as
pa:t of the corrective action for the previous enforcement action, has the same or
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similar root cause as the violation for which enforcement action was issued, does
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not substantially change the safety significance or character of the regulatory
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concern arising out of the initial violation and was or will be c
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not be characterized at a Severity Level I. (NCV 50 317,318A.d-10-02)
Anoendix R isolation Hand Switches
The licensee identified that Appendix R isolation hand switches (control transfer
switches) installed in the safe shutdown panel were single fused and may not
operate properly in the event that the fuse is blown because of a fire in the control
room. The inspector found that the licensee evaluated this concern against
Information Notice (lN) 85-00, " Isolation Transfer Switches arid Post-Fire Shutdown
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Capability," and issued an engineering package to perform modifications to provide
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dual fusing, such that in the event a remote fault blows a control power fuse when
the hand switch is in " Local," control power will still be available to the circuit. The
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licensee _ issued an engineering package, which the inspector found acceptable, to
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modify the hand switch circuits accordingly. The inspector noted that the
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modifications had been completed for Unit 1 during the 1998 RFO and Unit 2
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modifications had been scheduled to be completed during the 1999 RFO. The
inspector also noted that the licensee had implemented appropriate compensatory
actions for Unit 2 until the modifications are completed.
This violation of requirements stated in 10 CFR 50, Appendix R, Ill.L.3, " Alternate
and Dedicated Shutdown Capability," is not being cited, in accordance with
Section Vll.B.4 of the General Statement of Policy and Procedures for NRC
Enforcement Actions (Enforcement Policy) since it was identified by the licensee as
part of the corrective action for the previous enforcement action, has the same or
similar root cause as the violation for which enforcement action was issued, does
not substantially change the safety significance or character of the regulatory
concern arising out of the initial violation and was or will be corrected, and would
not be characterized at s Severity Level I. (NCV 50 317,318/98-10-03)
Motor-Ocerated Valve (MOV) Issues
The licensee had identified a condition which could cause a hot short in MOV
control cables that would bypass MOV limit switches, cause spurious operation,
and potentially damage the valve. The inspector found that the licensee evaluated
this issue against IN 92-18, " Potential for Loss of Remote Shutdown Capability
During a Control Room Fire, and Generic Letter (GL) 89-10, Safety Related Motor-
Operated Valve Testing and Surveillance," ultimately determining, that modifications
were necessary for MOVs needed for safe shutdown. The licensee had issued an
acceptable engineering package to modify thirty-two MOVs for Unit 1 and Unit 2.
The modifications to the MOVs consisted of rewiring Appendix R circuits at the
motor control centers in accordance with the recommendations of IN 92-18 and
replacement of MOV hand switches for circuits affected by shorts in the limit
switch cable. The inspector verified that the modifications had been completed for
Unit 1 during the 1998 RFO and Unit 2 had been scheduled to be completed during
the 1999 RFO. The inspector noted that appropriate compensatory actions were in
place for Unit 2 until the modifications are completed. The compensatory actions
implemented consisted of controls of hot work and transient combustible
walkoowns or fire watches.
This violation of requirements stated in 10 CFR 50, Appendix R, Ill.G.1.a, " Fire
Protection of Safe Shutdown Capability," is not being cited, in accordance with
Section Vll.B.4 of the General Statement of Policy and Procedures for NRC
Enforcement Actions (Enforcement Policy) since it was identified by the licensee as
part of the corrective action for the previous enforcement action, has the same or
similar root cause as the violabon for which enforcement action was issued, does
not substantially change the safety significance or character of the regulatory
concern arising out of the initial violation and was or will be corrected, and would
not be characterized at a Severity LevelI. (NCV 50-317,318/98-10-04)
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Accendix R Self-Assessment Topics
Further review of the licensee's Appendix R self-assessment by regional
management resulted in additional questions on seven of the issues. On
November 18,1998, a meeting was held at NRC headquarters with BG&E, the
Plant Systems Branch, NRR, and the Electrical Engineering Branch, Region I, to
discuss / resolve the seven issues identified in an October 22,1998, letter to the
licensee. The information presented at this meeting is provided as an enclosure to
this inspection report. The topics and resolution of these topics are documented
below.
External Hot Shorts
The Appendix R self-assessment report recommended that BG&E re-evaluate
Appendix R safe shutdown component circuits and consider all single external hot
short cable faults.
BG&E's original Appendix R design approach assumed hot shorts between
conductors within a cable and multiple cables for high/ low pressure interfaces only.
The inspector reviewed the safety evaluation report (September 27,1982) and
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concluded that the licensing basis appeared not to require the licensee to consider
all external hot short in their analysis. Therefore, no violation of NRC requirements
occurred.
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However, as an enhancement, the licensee instituted a plan to perform cable to
cable hot short analysis including all cables that could affect safe shutdown. BG&E
had planned to consider all spurious actuations as part of this analysis. The
licensee expected to complete the analysis for this task by January 1999. This
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would include istuance of a new interactive cable analysis and revision to their
AOP-09 procedures. The NRC staff concluded that the actions taken by the
licensee were acceptable.
Reoortability
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The Appendix R self-assessment report recommended that the reportability of
potential Appendix R non-conformance be re-evaluated.
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BG&E identified an example of an Appendix R reportable issue in their Appendix R
self-assessment. In the example, BG&E determined that the RCS/LPSI suction
valves (MOV-651 and 652) could open based on a postulated fire in several
locations since the breaker for at least one of the valves in series had not been
placed in the "OFF" position during normal plant operation. This is a condition that
would not meet the requirements of 10 CFR 50, Appendix R, section Ill.G.1.a, " Fire
Protection of Safe Shutdown Capability," thus placing the plant outside of its design
basis. This failure is further discussed in the high/ low pressure interface section of
this report. The inspector concluded that this condition was reportable under
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The licensee stated that NUREG 1022," Event Reporting Systems 10 CFR 50.72
and 50.73," revision 0, did not provide specific guidance on the definition of,
"outside the design basis of the plant" and that their reportability threshold did not
identify Appendix R issues as a reportable condition because they were not
considered a condition, "outside the design basis of the plant." The licensee had
instituted a plan to revise their reportability criteria to meet the guidance outlined in
NUREG 1022, revision 1, stating that this revision includes guidance on what,
"outside the design basis of the plant" means and provides several specific
examples of Appendix R reportable issues. BG&E planned to complete this effort by
the Spring of 1999.
The inspector reviewed GL 86-10 and found reportability was addressed in
paragraph E, " Notification of the NRC when Deficiencies are Discovered" of the
cover letter. GL 86-10 reminds licensees of their obligation to notify the NRC of fire
protection deficiencies which meet the criteria of 10 CFR 50.72 or 10 CFR 50.73 as
applicable. The inspector reviewed NUREG 1022, revision 0, and found that the
guidance given did not provide specific examples of Appendix R reportable issues.
The guidance provided in revision 0 could be interpreted in many ways giving
licensee's leeway to establish their own thresholds. Based on the age of this issue
and the lack of clear guidance given the circumstances, the failure to report the
above condition constitutes a violation of minor significance and is not subject to
formal enforcement action. Based on the review above, the NRC staff concluded
that the actions taken by the licensee to upgrade their reportability criteria using
NUREG 1022, revision 1 was adequate.
Self-Induced Station Blackout
The Appendix R self-assessment report recommended that the self-induced 4 kV
bus blackout actions be re-evaluated and that cooling water (and other plant
supports) needed by the emergency diesel generators (EDGs) should be provided by
performance of plant modifications and/or system lineup procedure changes,
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BG&E reviewed an issue that occurred at another nuclear facility regarding a
concern that the diesels, if running too long without service water in an Appendix R
scenario, may result in failure. Based on their review, BG&E determined that there
is reasonable assurance that their AOP-9 procedures will protect the originally
installed diesels (1B,2A, and 2B) from this occurrence by shutting them down
when service water is lost under certain post-fire conditions. BG&E determined that
no AC power is needed for 90 minutes and their AOP-9 procedures ensures
operators will restore AC power within 60 minutes. The inspector reviewed a letter
to the NRC from BG&E, dated May 14,1982, describing the action of shutting
down the originally installed diesels to align cooling water. The inspector
determined BG&E's actions were consistent with the wording in the May 14,1982
letter and their licensing basis. The inspector also reviewed the protective functions
listed in the UFSAR for the originally installed diasels and found no functions that
would affect diesel startup once cooling water was aligned. No violations of NRC
requirements were identified. The NRC staff concluded that the actions taken by
the licensee were adequate.
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Raceway Enclosure
The Appendix R self-assessment recommended that BG&E re-evaluate the basis for
acceptability of a one-hour conduit enclosure installed on charging pump number 11
power feed (room 115C).
BG&E performed an engineering evaluation of the one-hour fire barrier that encloses
conduit containing the number 11 charging pump power cable conduit where it
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traverses the number 13 charging pump room. This evaluation determined that the
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configuration was acceptable and that smoke detection and sprinkler systems in the
area along with low combustible loading ensured that the fire exposure to the
enclosure would be minimal. The inspector verified that smoke detection, sprinkler
systems, and low combustible loading were present where the power cable conduit
traverses the number 13 charging pump room during a walk down of AOP-9
procedures.
The NRC staff was concerned that the configuration was not acceptable with
respect to meeting Appendix R requirements. However, the licensee indicated that,
for a potential fire in the number 13 charging pump room, the number 12 charging
pump would be relied upon to place the plant in safe shutdown. The licensee
indicated that the number 11 charging pump was a redundancy, which they believe
would be available based upon the above evaluation. The NRC concluded that the
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number 12 charging pump would assure that the plant could be placed in safe
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shutdown for a fire in the number 13 charging pump room, therefore no violations
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of NRC requirements were identified. The NRC staff concluded that the actions
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taken by the licensee were adequate.
Manual Reoair issues
The Appendix R self-assessment recommended that BG&E re-evaluate the use of
wrenches and fuse pullers (tools) which may constitute a hot shutdown repair.
BG&E has evaluated the issue of manual repairs and had determined that their
licensing basis supports their current approach to achieving hot shutdown. The
inspector reviewed a letter to the NRC dated September 30,1981,in which the
potential of removing fuses and disconnecting air lines from valves by operators
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was described by BG&E. The inspector found that these actions were consistent
with the licensing basis. The inspector also reviewed a previous NRC inspection
report (IR 84-04) and found previous review of operator actions to reach hot
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shutdown were found to be acceptable. Additionally, BG&E trained their operators
to pull fuses and to break air compression fittings, if necessary. Through these
reviews by the inspector, it appeared that BG&E was within their licensing basis.
No violation of NRC requirements were identified. The NRC staff concluded that the
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actions taken by the licensee were adequate.
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Multiole Hiah Impedance Fault (MHIF) Analysis
The Appendix R self-assessment recommended that BG&E complete an AC and DC
Multiple High impedance Fault analysis.
BG&E had completed calculation 95-0049," Multiple High Impedance Faults-AC
Distribution System," revision 0, and was reviewing calculation CA04043," Multiple
High Impedance Faults - 125 VDC Distribution System," for approval. BG&E had
planned to approve this calculation by the Spring of 1999. The inspector reviewed
BG&E's approach to performing a MHIF analysis and determined that BG&E used a
worst-case bounded approach that considered all shutdown circuits. The inspector
held discussions with NRR staff and Brookhaven National Laboratories personnel to
determine if the bounded methodology approach was acceptable. The NRC staff
concluded that the approach taken by the licensee to perform a bounded MHIF
analysis appeared reasonable and was acceptable.
Hiah/ Low Pressure interface
The Appendix R self-assessment report recommended that BG&E revise procedures
to reflect new breaker configurations for high/ low pressure interfaces. The report
also recommended that a section be added to the interactive cable analysis to
address the basis for exclusion of potential high/ low pressure boundary paths
(e.g., reactor head vents and pressurizer PORVs, etc.).
BG&E had determined that the wording in the self-assessment project plan was
confusing and that they did consider PORVs, Reactor Head Vents, and MOV-651
(one of two Shutdown Cooling Return isolation Valves) as high/ low pressure
interfaces. However, the Appendix R self assessment identified a condition in
which the RCS/LPSI suction valves (MOV-651 and 652) could open based on a
postulated fire, since the breaker for at least one of the valves in series had not
been placed in the "OFF" position during normal plant operation. This is a condition
that would not meet the requirements of 10 CFR 50, Appendix R, section Ill.G.1.a,
" Fire Protection of Safe Shutdown Capability." As a result of this finding, BG&E
created an issue report to evaluate this condition. BG&E determined that a change
in operating procedures to lock the MOV-651 breaker open with the valve in the
closed position was necessary to prevent a fire from causing spurious operation of
the valve. BG&E had revised the appropriate procedure to lock the MOV-651
breaker open. BG&E has also revised the appropriate procedure to deenergize both
PORVs by placing their associated breakers to "OFF." The inspector verified these
actions through review of operating procedures and the issue report. The inspector
reviawed the basis for these manual actions and determined that they were taken to
preserve the RCS due to spurious operation of these valves during an Appendix R
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fire scenario. The NRC staff concluded that the manual actions taken by the
licensee were adequate.
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This violation of requirements stated in 10 CFR 50, Appendix R, Ill.G.1.a, " Fire
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Protection of Safe Shutdown Capability,"is not being cited,in accordance with
Section Vll.B.4 of the General Statement of Polic't and Procedures for NRC
Enforcement Actions (Enforcement Policy) since it was identified by the licensee as
part of the corrective action for the previous enforcement action, has the same or
similar root cause as the violation for which enforcement action was issued, does
not substantially change the safety significance or character of the regulatory
concern arising out of the initial violation and was or will be corrected, and would
not be characterized at a Severity Level I. (NCV 50-317,318/98-10-05)
Conclusion
The licensee's Appendix R program self assessment was of good quality and was
effective in identifying non-compliances and areas for improvement. In response to
these findings, the licensee implemented effective corrective actions, including plant
modifications to motor-operated valve circuits and Appendix R hand switches, and
enhancements to abnormal operating procedures (AOPs). Appropriate
compensatory actions were taken for required changes that were planned, but not
yet completed. Additional analyses to review all cable to cable hot shorts, which
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could affect the ability of the plant to reach safe shutdown, was a good initiative.
The completion schedule for resolution for identified issues was sgpropriate.
Resolution of the seven issues outlined in the October 22,1998, letter to BG&E
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were adequate. The licensee's Appendix R se f-assessment identified five non-
compliances. These licensee-identified and corrected violations were dispositioned
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as non-cited. (NCV 50-317,318/98-10-01 through 98-10-05)
F8.2 (Closed) Unresolved item 50-317.318/92-27-02: Control room ventilation
' Appendix R concerns. Inspection Report 50-317,318/92-27, section 7.3,
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documented Appendix R fire concerns in which the licensee had not completed a
detailed evaluation to more accurately determine the adverse affects of losing both
trains of control room heating, ventilation and air conditioning (HVAC) following a
postulated fire. The inspector reviewed documents related to the corrective actions
of this deficiency.
The inspector found that the licensee had completed a detailed analysis of the
effects of a fire in different areas of the plant that could potentially disable both
trains of the control room HVAC system. The inspector also found that the
licensee's calculations determined that without any cooling, the control room and
cable spreading room may heat-up to high enough temperatures, that continued
operation of the safe shutdown equipment in those rooms would be marginal. As a
result of these findings, the licensee prepared a modification package to install fan
coil units and staged flexible hoses to provide cooling air to the control room and
cable spreading room HVAC ducts in the event both HVAC trains are lost due to
fire. The inspector found that the engineering package (including 10 CFR 50.59
evaluations and calculations) for this modification was acceptable and that
installation of the modification had begun, with a p;anned completion date of the
end of 1998. The inspector also found that the engineering package contained
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sufficient documentation, acceptable installation instructions, and acceptable post-
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modification testing to ensure' operability of the modification. The inspector verified
-that various facets of the installation were in place during a walkdown of the
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system. The inspector noted that the scope of this project was expanded to include
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chiller replacement, economizer cycle deletion, tornado related modifications, as
well as Appendix R modifications.
The inspector concluded that the licensee had performed an acceptable evaluation
to determine the affects of losing both trains of control room HVAC following a
postulated fire. The inspector also concluded that the engineering package to install
this modification was acceptable. No violations of regulatory requirements were
identified during review of this issue. This item is closed.
F8.3 IC_losed) Notice of Violation (NOV) 50-317.318/96-05-01: Failure to provide
adequate protection against consequential damage of a fire in the 45 ft switchgear
room (loss of ventilation to 27 ft switchgear room). An evaluation performed by a
contractor did not support long term operation of the equipment needed to
shutdown the reactor at temperatures of up to 150 F. The inspector reviewed
documents relating to corrective actions of this deficiency.
The inspector reviewed the corrective actions stated in the licensee's response
letter to the NOV, dated August 23,1996, and found the implementation
acceptable, in particular, the inspector reviewed engineering evaluation
ES199601186, revision O. The inspector found that the licensee had analyzed
equipment needed to shut the reactor down following a loss of ventilation in the
45 ft and 27 ft switchgear rooms and found that this equipment would be operable
under these conditions. The inspector found that the evaluation supports safe-
shutdown equipment operation in the 45 ft and 27 ft switchgear rooms. During a
walkdown of the switchgear rooms, the inspector verified that two fans for each of
the switchgear rooms was staged to provide adequate cooling in the event
ventilation is lost in those rooms.
The licensee also committed to perform an Appendix R compliance overview
evaluation. The review of the Appendix R self-assessment is discussed in section
F8.1 of this report.
Additionally, the licensee committed to initiate an Appendix R training program for
engineering personnel and engineering management. The focus of this training was
to raise the level of knowledge of Appendix R among site engineers. The inspector
verified the implementation of this program by witnessing a class given on July 9,
1998. The class provided the following learning objectives and was presented by
fire protection engineering personnel:
Understanding the PotentialImpact of Fire at Calvert Cliffs
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Understanding the Development of Fire Protection Requirernents
Understanding the Primary Objective of 10CFR50, Appendix R
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Understanding the Basic Elements of Appendix R Compliance
Understanding the Calvert Cliffs Fire Protection Program
Defense in Depth Approach as it relates to the Fire Protection Program
Current NRC and Industry Fire Protection / Appendix R issues
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The inspector attended the class and found it to be well planned and informative.
The class provided a good overview of Appendix R and fira protection issues and
provided acceptable training to engineering and management personnel.
- The inspector concluded that appropriate and acceptable corrective actions had
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been implemented by the licensee. The inspector also concluded that the licensee
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performed an acceptable evaluation of safe shutdown equipment operation in the
45 ft and 27 ft switchgear rooms.
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V. Manaaement Meetinas
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Exit Meeting Summary
The inspector presented the inspection results to members of licensee management at an
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exit meeting on July 10,1998, and a supplemental exit meeting on December 3,1998.
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The licensee acknowledged the findings presented.
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The inspector asked the licensee whether any material reviewed during the inspection
should be considered as proprietary information. No proprietary information was identified.
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The inspector indicated to the licensee that the slides presented to the NRC at the meeting
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held at NRC headquarters on November 18,1998, would be included as an enclosure to
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this report. These slides provided BG&E's response to questions provided to them in a
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letter from the NRC dated October 22,1998,
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PARTIAL LIST OF PERSONS CONTACTED
Calvert Cliffs (BG&E)
J.
Biggans, Senior Assessor
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Buttner, Senicer Engineer DES
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Cellars, Manager - Nuclear Energy Division
G.
Cooper, Sr. Electrical Engineer (Bechtel)
C.
Cruse, Vice President - Nuclear Energy Division
G.
Detter, General Supervisor - Design Engineering
K.
Eser, Regulatory Analyst
D.
Findlay, Field Engineer - Fire Protection
A,
Henni, Senior Engineer - MEU
P.
Katz, Plant General Manager
C.
Ludlow, Principal Engineer - MEU
E.
McCann, Electrical Engineer
J.
Osborne, Director - NRM (Acting)
M. Polak, Supervisor - EAU
'
P.
Robinson, Assessor - Nuclear Performance Assessment Department
C.
Sinopoli, Appendix R and Fire Protection Engineer
C.
Sly, Senior Engineer, NRM
R.
Sydnor, Appendix R Project Manager
J.
Wood, Fire Protection Design Engineer
NBC
F.
Bower, Resident inspector
l
A.
Dromerick, Project Manager for Calvert Cliffs - NRR
D.
Lew,. Chief, Electrical Engineering Branch
L.
Marsh, Chief, Plant n 7 stems Branch - NRR
P.
Qualls, Fire Protection Engineer - NRR
W. Ruland, Chief, Electrical Engineering Branch (on temporary assignment)
J.
Stewart, Senior Resident inspector
K.
West, Chief. Plant Support Systems Section - NRR
- - - - -
- - - - -
-
-
'
.
.
INSPECTION PROCEDURES USED
IP 92904:
Followup - Plant Support
ITEMS OPENED, CLOSED, AND DISCUSSED
noened
50-317,318/98-10-01
NCV emergency lighting was inadequate in Unit 1 MSIV
room and the Unit 2 emergency shutdown panel
50-317,318/98-10-02
NCV air bottles stored in wrong location for a fire in
room 529
50-317,318/98-10-03
NCV Appendix R isolation hand switches were single fused
50-317,318/98 10-04
NCV hot shorts in MOV control cables could bypass MOV
limit switches, cause spurious operation, and potentially
damage the valve
50-317,318/98-10-05
NCV RCS/LPSI suction valves could open based on a
potential fire
Closed
50-317,318/97-08-08
potential issues identified during appendix R self
assessment to be not in compliance with regulatory
compliance
50-317,318/92-27-02
control room ventilation Appendix R concerns
50-317,318/96-05-01
failure to provide adequate protection against
consequential damage of a fire in the 45 foot
switchgear room (loss of ventilation to 27 foot
switchgear room).
50-317,318/98-10-01
NCV emergency lighting was inadequate in Unit 1 MSIV
room and the Unit 2 emergency shutdown panel
50-317,318/98-10-02
NCV air bottles stored in wrong location for a fire in
room 529
50-317,318/98-10-03
NCV Appendix R isolation hand switches were single fused
50-317,318/98-10-04
NCV hot shorts in MOV control cables could bypass MOV
limit switches, cause spurious operation, and potentially
damage the valve
50-317,318/98-10-05
NCV RCS/LPSI suction valves could open based on a
potential fire
. . . . .
. .
.
.
..
..
.
_ ._
_.
___
_. _
_
,
,
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1
LIST OF ACRONYMS USED
Alternating Current
i
i
Abnormal Operating Procedure
Direct Current
BG&E
Baltimore Gas & Electric
CFR
Code of Federal Regulations
!
I
DRS'
Division of Reactor Safety
EEB
Electrical Engineering Branch
GL
Generic Letter
,
' -
Heating, Ventilation anri Air Conditioning
Interactive Cable Analysis
IN -
Information Notice
'
IR
inspection Report
kV-
Kilovolt
-LPSI
Low Pressure Safety injection
Motor Operated Valve
MHIF
Multiple High Impedance Fault
-NCV
Non-Cited Violation
l
NRC
Nuclear Regulatory Commission
'
Nuclear Reactor Regulation
!
Pressure Operated Relief Valve
!'
Refueling Outage
Vac
Volts Alternating Current
Vdc
Volts Direct Current
Updated Final Safety Analysis Report
Unresolved item
l
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['
. _.
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,
,
-
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!
I
BGE Response to NRC
l
Questions Concerning
Appendix R Self Assessment
i
Introductions
BGE Attendees
-
l
- Kevin Cellars, Manager-Nuclear Engineering Depanment
- Gary Detter, General Supervisor-Design Engineering
- Russ Sydnor, App. R/HVAC Project Manager
- Bruce Montgomery, Director-Nuclear Regulatory Matters
- John McVicker, Principal Engineer-Procurement
- Craig Sly, Senior Engineer; NRM
- Cliff Sinopoli, Senior Engineer-DES
i
- Ed McCann, Engineer DES
l
- Rich Buttner, Senior Engineer DES
- Mark Hogg, Reactor Operator
- Gary Cooper, Bechtel
2
!
.
.
Introduction
BGE will provide a brief overview of our Appendix R
history.
BGE will provide an update on the status of the ections
associated with our Appendix R Self Assessment.
- BGE will provide answers to the questions from NRC
October 22,1998 letter.
>
Introduction
- The 1996 Appendix R Self Assessment was a
comprehensive review of the entire App. R program.
- Resulting project plan included proposed resolutions and
schedule, which considered safety significance,
compliance, and resources.
. When the project plan actions are completed BGE's
App. R program will have been substantially enhanced.
-
- We welcome this opportunity to answer the questions
raised in your October 22,1998 letter relative to the self
assessment.
4
,
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_ _ _ _ .
_
_
--
- _ _
. _ _ _ .
. _ _
_
__
. _ _
_ _
,
,
I
Calvert Cliffs Appendix R History
1981/1982 description of App. R program was submitted
-
to NRC.
l
September 1982, NRC issued third supplement to the Fire
-
'
Protection Safety Evaluation Report.
March 1984, NRC performed App. R inspection with no
l
violations, deviations or other unacceptable conditions
identified.
1989 - 1991 self-identified Appendix R issues.
-
1992 EDSFI identified Switchgear Room HVAC potential
-
common mode failure.
1993 Internal Task Force identified issues with App. R.
,
i
Calvert Cliffs Appendix R History
1996 NOV on switchgear room ventilation
1996 Appendix R self assessment
1997 Presentation of self assessment results
to Region 1
1997 Project Plan approved
'
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c
-
-
- -
-
-
-
--
-
-
-- -
- -
.
.
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l
Status of App. R Self Assessment Issue
l
Resolution
34 items identified.
21 items complete.
2 modifications scheduled for Unit 21999
re beting outage (Unit I completed).
6 items awaiting completion of reanalysis and
resulting procedure changes.
- ECD Late 1999
5 scheduled for completion in early 1999.
7
NRC Inspections in 1998
January - two week fire protection and App.
R Inspection with positive results.
(Inspection Report 97-08)
June and July -Inspection of self
assessment issues-and project plan actions.
Exit meeting cited positive results. (Open
Inspection Report 98-10)
i
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!
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e
1
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i
Response to Questions
Response to the questions will be in the order
-
presented in the October 22,1998 letter.
- External Hot Shorts
- Reponability
- Diesel Generator Shutdown
- Raceway Enclosure
- Manual Actions
- Multiple High knpedance Faults
- High/ Low Pressure Interfaces
,
External Hot Shorts
SA-1
"... please explain whether you agree or
disagree that Appendix R requires that you
evaluate all possible functional failure
states, including postulated cable to cable
faults and provide your basis. Also please
describe your assumptions for the analysis
currently underway and your projected
completion date."
i.
. , .
.
.
.
.
.
_
..
,- --.
.
. - . -
-
..
- . - -
-
-
,
- -
-
.
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External Hot Shorts
l
' Original Appendix R Design Approach
l
- Hot shorts between conductors within a cable
assumed.
- Hot shorts between multiple cables, considered
for hi/lo pressure interfaces, but not for other
components.
1
- Silicone-Asbestos jacketed cable insulation
'
used on low and medium voltage AC/DC
cables.
i,
i
External Hot Shorts
Voluntarily performing cable to cable hot
short analysis.
]
All cables that could affect safe shutdown
(including Associated Circuits) are
included.
.
Considered All Spurious Actuations/ Signals
as part of the analysis.
l
>>
,
i
_ _ -
._
_
._
. . _.
_ _ _ _ _
.
_._
- . _ _ _ _ . . _ _ _ - _ .
,
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Reportability
'
SA-4
!
Basic issue: Reportability of Appendix R Issues
-
l
Event ofinterest
-
l
- RCS/LPSI Suction valves could open based on
l
postulated fire in several locations. Explain
l
your basis for not reporting this particular
Appendix R issue and other issues as
,
appropriate.
Also, state your plans to revise your reportability
-
procedures and criteria.
>>
Reportability
NUREG 1022 Rev 0 (1983) and Statement of
a
.
Considerations for th'e LER rule (1983) did not proside
specific guidance on the definition of, "outside the design
basis of the plant"
- BGE used the background information on other parts of
-
50.73 (a) (2) (ii), engineering judgment, and industry input
to develop a reportability threshold for outside the design
basis of the plant
_
- BGE's reportability threshold did not identify
Appendix R issues as reportable because they were not
considered a condition, "outside the design basis of the
plant."
i.
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e
.-
. _. -
.
-
_-
.
_
..
.
-
.
--
.-
.
.
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Reportability
NUREG 1022, Rev 1 (January 1998)
provided new guidance on reportability of
l
Appendix R issues.
l
-it provides guidance on what outside the design
!
basis of the plant means
l
- it provides several examples, some are specific
!
to Appendix R issues
l$
'
l
Reportability
in the future, BGE will report Appendix R issues
-
where post fire safe shutdown capability is found
to be lacking
- BGE is monitoring issue reports for conditions that fall
into this reportability criteria
- BGE has completed training of many onsite groups that
identify and evaluate issues
- BGE has placed the new NUREG 1022 Rev 1 guidance
on our internal internet for reference
,
- Procedure changes will be complete by the end of the
year
l
is
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_,
_ _ _ _
___
_ _ _ _ .
_ _ _ _ _ _ _ _ _
. _.
___
-_ . _ _ _
%
1
Diesel Generator Shutdown
l
SA 5
l
... please explain your basis for the actions
"
taken to shutdown the diesel generators
under certain post-fire scenarios and the
reason this is acceptable. Also, state your
final plans to resolve this issue."
17
Diesel Generator Shutdown
- Original EDG's use service water for
cooling.
i
EDG shutdown until cooling water aligned
was described to NRC in 5/14/82 letter.
New EDG's reduced the need for EDG
shutdown from 11 rooms to 2 rooms.
- Specifically routed cable to enhance App. R
i
18
. _ .
,
,
-
.
_.
.
_ - .
_ = .
-.
.
--
-
Diesel Generator Shutdown
Off-site power is not isolated if available.
AC power is not isolated to eliminate
spurious actuations/ signals.
EDG shutdown only to protect diesel.
- Restarted once cooling water aligned
19
Diesel Generator Shutdown
EDG shutdown immediately from the
Control Room to prevent damage.
EDG restarted and tied onto bus if needed.
Engineering analysis demonstrates no AC
power is required for 90 minutes.
- Procedure ensures Operators will restore
AC power within 60 minutes.
,
,
-
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--
-
. - _
_-
.
.
.- _..
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!
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Raceway Enclosure
SA-6
l
l
l
... please explain your basis for installing a
"
l
1-hour rated enclosure on charging pump
No.11 powerfeed and how the installation
conforms to the requirements of App. R and
to the guidance in GL 86-10, response 3.2.2.
!
Also explain how you determined the
enclosure meets the requirements."
21
Raceway Enclosure
The #12 Charging Pump is available for a
fire in the #13 Charging Pump Room.
- 11 Charging Pump is not required for a fire
in the #13 Charging Pump Room.
"
!
,
4
.. .
_
.-
a - -
-._...-. .
.----
.-
.
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powerW for #13
Reem i!4, Fn Area iI
<
,owerW for,.,
>
!
.n ~
I
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ggy
!
h#d
ggps
'
l
l
6 %, y
g;ei y
c:ini
f
u
.;
l
-
O
_
"
Room!!5A
'%
Fn Aree 5
-
7[
.
N
l f. . . . . . . . . . . . . . . . , . j '
.,
b*
Tansfer
N,.
. g-
-
owe,u
~
._,
Fn mee 10
,owerW for
.ii ~ ,.,
,m,, ,em
is sus
23
Manual Actions
SA-7
" . . . please explain your basis for using
wrenches and fuse pullers, as stated in your
AOP procedures, to bring the plant to a hot
shutdown condition. Also, explain how the
'
use of tools meets the intent of your
licensing basis."
.
2
I
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,
.-
-
_
. . -
-.
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,
Manual Actions
Pulling fuses and removing air from valves
j
described to NRC in 9/30/81 submittal -
ICA Rev. O.
1984 App. R Inspection Report describes
!
-
review of safe shutdown procedure.
l
BGE considers these operator actions as
L
reviewed by the NRC and acceptable to
l
achieve hot shutdown.
u
i
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I
Manual Actions
These actions are part of normal operator
-
qualifications and are not considered repairs
because:
- Operators trained to pull fuses
,
- Required fuses clearly described in procedures
- Operators trained in breaking compression
fittings.
l
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,-
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.
.
I
I
Manual Actions
- Personnel safety concerns mitigated by
j
training and use of fuse pullers.
- Walkthrough training on the procedures
l
accounts for time needed to perform manual
actions.
Our actions have been reviewed and
accepted by the NRC.
21
Multiple High Impedance Faults
SA-16
... please explain your basis for not
"
performing MHIF evaluations on all AC
and DC Appendix R safe shutdown circuits
using guidance provided in GL 86-10."
.
l
se
l
__
.
.
.
Multiple High Impedance Faults
BGE bounding analysis does consider all Shutdown
a
circuits.
AC MHIF analysis considered technically correct
.
by Self Assessment Team.
Calvert Cliffs relas on fuses, not breakers for DC
-
and vital AC, so GL 86-10 approach not directly
applicable and will not work.
Calven Cliff; arealysis methodology is conservative
and an improvement to GL 86-10 approach.
n
High/ Low Pressure Interface
sA-33
... please explain your basis for documenting the
"
exclusion of PORV's, reactor head vents, and
MOV-651 as high/ low pressure interface valves.
Also, please explain procedural changes made to
stop spurious actions from causing these valves to
open. Additionally, please explain how you
derv astrated the plant can be safely shutdown
with a RCS release and what is your basis."
'
=
_ _ _ _ _
r
,
_
_.
._._ _._.
_
_ _ ._ _.. _ _ _.
- _ . . _ _ _ . _
_ . _ _ _ . . _
.
!
l
High/ Low Pressure Interfaces
!
' Project plan wording was confusing.
j
PORV's, Reactor Head Vents, and MOV-
l
651 are considered Hi/Lo pressure
i
interfaces.
l
- Manual actions to mitigate consequences of
Hi/Lo interfaces are placed at the beginning
of procedures.
- RCS release has been analyzed.
l
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!
!
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l
Conclusion
l
l
Calvert Cliffs maintains an active approach to
the Appendix R program.
Approaches taken represent not only licensing
basis but always consider safety significance.
(
We believe that we have addressed each of the
questions raised in the October 22,1998 letter.
l
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J
SELF ASSESSMENT
11/18/98
~I
SCOPE TASK SUMMARY
,
1 COMPLETE
DESIGN /
ANALYSIS
RESP.
TASK
ASSIGNED
WORK COMPL'T
PERSON
STATUS
COMMENTS
PRIORITY
NUMBER
TASK TITLE
DISCIPLINE
Analysis approx. 98% complete. Issue
,
(NRC-1)
ECD-
new ICA in first quarter 1999. Revise
~
GRP-1
- SA - 1
External Hot Shorts
Electrical
WORKING
NO
E.McCann
10/30/99
AOP-09 procedures by 10/30,99_
.
GRP-I
SA-2
Emergency Ughts
.
YES
YES
C. Sinopou
COMPLETE
Cornplete, Notebook Available
.
-
I
i
!
GRP-I
SA-3
.
Electrical
YES
YES
R. Sydnor
COMPLETE
Complete, Notebook Available
t
(NRC-2)
ECD-
Pending completion of follow-up
GRP-l
- SA - 4
N/A
NO
LM
(NRC-3)
'
GRP-I
- SA - 5
Self induced Station Blackout
YES
YES
h
COMPLETE
(NRC-4)
GRP-I
- SA - 6
Raceway Fire Barrier WC
YES
N/A
J. Wood
COMPLETE
(NRC-5)
GRP-I
- SA - 7
Manual Actions Tools
YES
N/A
C. Sinopou
COMPLETE
Complete. Notebook Available
l Electrical I
YES
ECD - 99
Unit 1 is complete. Unit 2 will complete
ES199602079
RFO + 60
during 1999 RFO. Per Ed Emery x-
l
WORKING
E.McCann
Days
2256
GRP-2
SA-8
Dual Fusing. InfoNotice 85-09
IYES
ECD - 99
ES199602091
RFO + 60
Unit 1 is compt. Unit 2 ECD 99 RFO.
WORKING
E.McCann
Days
Non outage by 11/98. Ed Emery x-2256
l
GRP-2
SA-9
MOVs, InfoNotice 92-18
Electrical -
l Electrical l WORKING
ECD-
SEE SA-01 COMMENTS FOR
NO
E. McCann
10/30/99
STATUS AOP-09 procedure revisions.
GRP-2
SA - 10
Spurious Operation
!
I
Large Fire Areas
.
,
,E
E.McCann
YES
N/A
J. Wood
COMPLETE
GRP-2
SA - 11 Fire Areas - 10 and 11
'
E.McCann
YES
N/A
J. Wood
COMPLETE
Complete. Notebook Available
GRP-2
SA - 12 : Fire Area - Auxiliary Building Roof
Prehm Analysis by SE does not indicate
C. Sinopoli
ECD-
a challenge to SS. AOP-09 procedure
GRP-2
SA - 13
Instrument Air Functio ality___
Electncal
NO
NO
C. Faller
10/30/99
h ed.____.___
..
GRP-2,
SA - 14
Air Bottfe, CV-517
-
N/A
YES
C.5:no- li
COMPLETE
Complete, Notebook Available
A
NRC MEETING 11/1&S8
Page 1
'
.
3
SELF ASSESSMENT
11/18/98
'
SCOPE TASK SUMMARY
i
DESIGN /
7
TASK
ASSIGNED
ANALYSIS
RESP.
!
PRIORITY
NUMBER
TASK TITLE
DISCIPLINE
COMPLETE
WORK COMPL'T
PERSON
STATUS
COMMENTS
GRP-2
SA-15
Instrument Sensing Lines
Electrical
YES
YES
E.McCann
COMPLETE
Complete. Notebook Available
(NRC-6)
.
E.McCann
ECD-
AC complete. DC in review - E.
GRP-2
- SA - 16
Multiple High impedance Faults
Electrical
YES
NO
R. Buttner
M
McCann
G. Wolf
A. Henni
ECD-
Modification to CR HVAC in progress.
t
'
GRP-2
SA - 17
YES
NO
R. Sydnor
10/30/99
AOP-09 procedure; changes required.
M. Hogg
GRP-2
SA-18
YES
YES
h
COMPLETE
GRP-2
SA-19
Embedded Conduits
YES
N/A
J. Wood
COMPLETE
j
GRP-2
SA-20
Fire Suppression Effects
YES
N/A
J. Wood
COMPLETE
Cornplete, Notebook Available
GRP-3
SA - 21
Process Monitoring ________
Electrical-
YES
YES
E.McCann
COMPLETE
Closed during Self Assessment
Cc. Tile references and develop
GRP-3
SA - 22
Fire Barrier Evaluations
YES
YES
J. Wood
Complete
notebook.
ECD-
Compile References and develop
GPP-3
SA-23
YES
N/A
h
Compile References and develop
GRP-3
SA - 24
YES
N/A
hh
Notebook.
Have information on Handswitches
available needs to be inserte d i sto
GRP-3
SA - 25
Fire Damper Operability
YES
YES
J. Wood
Complete
FFSM during next revision.
E.McCann
Note book with analysis is in cabinet.
GRP-3
SA - 26
Communications
Electrical '
YES
YES
G. Kniertern
Complete
G. Knieriem is contact
Work is complete, new format has been
GRP-3
SA-27
ICA Format
Electrical ' l
YES
YES
E.McCann
COMPLETE
developed
Complete - ICA Attemate Safe
j
GRP-3
SA - 28
Report on Attemate Shutdown
Electrical l
YES
YES
E.McCann
COMPLETE
Shutdown Analysis has been revised.
NRC MEETING 11/18/98
Page 2
J
- SELF ASSESSMENT
11/18/93
2
SCOPE TASK SUMMARY
s
DESIGN /
TASK
ASSIGNED
ANALYSIS
RESP.
PRIORITY
NUMBER
TASK TITLE
DISCIPLINE
COMPLETE
WORK COMPL'T
PERSON
STATUS
COMMENTS
Approximately 98% complete. See SA-
-
ECD-
01 above. Indudedin newICA
GRP-3
SA - 29
Comprehensive Equipment List
Electrical
YES
WORKING
E.Me,Cann
10/30f99
Database.
Issue Reviewed, No Further Action
GRP-3
SA - 30
Electrical Distnbutkin Systems
Electrical
YES
YES
E.McCann
COMPLETE
Required
E.McCann
ECD-
Need Final Resolution by EEU Ken
GRP-3
SA - 31
Bmaker/ Fuse Coordination
Electrical
WORKING
NO
R. Buttner
Spring 1999
Sebra
GRP-3
SA - 32
Current Transformer Analysis
Elodrical
YES
YES
E.McCann
Complete
Complete, Notebook being prepared.
(NRC-7)
--
J. Wood
ECD-
Fire Analy-is Reovired for PORV's
GRP-3
4 SA - 33
High/ Low Pressure Interface
Electrical
YES
NO
E.McCann
Spring 1999
Enhancement, Work in progress
Acceptable. Will revise ES-20,31 & 44
ECD-
as applicable upon completeien of SA-
GRP-3
SA - 34
Long Term Compliance Procedures
Electrical
YES
NO
E.McCann
10/30/99
01.
1
- Those tasks identified in NRC letter dated October 22,1998 request for additional information
and justification in preperation for November 18,1998 Significant Meeting 98-82.
.
NRC MEETING 11/18/9e
Page 3
.
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_-_-_-
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