ML20117E616
| ML20117E616 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 08/23/1996 |
| From: | Cruse C BALTIMORE GAS & ELECTRIC CO. |
| To: | Lieberman J NRC OFFICE OF ENFORCEMENT (OE) |
| References | |
| NUDOCS 9608300107 | |
| Download: ML20117E616 (7) | |
Text
,
3cs CucLEs II. CCOSE Baltimore Gas and Electric Co an Vice President Calvert Cliffs Nuclear Power Plant Nuclear Energy 1650 Calven Cliffs Parkway Lusby, Ma.yland 20657 410 495 4155 August 23,1996 U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION:
Mr. James Lieberman Director, Office of Enforcement
SUBJECT:
Calvert Cliffs Nuclear Power Plant Unit Nos.1 & 2; Docket Nos. 50-317 & 50-318 Reply to Notice of Violation -- NRC Inspection Report Nos. 50-317(318V96-05
REFERENCES:
(a)
Letter from Mr. T. T. Martin (NRC) to Mr. C. H. Cruse (BGE), dated July 25,1996, Notice of Violation and Proposed Imposition of Civil Penalty - $50,000 (NRC Inspection Report Nos. 50-317/96-05 and 50-318/96-05)
Reference (a) forwarded a Nuclear Regulatory Commission Region 1 Notice of Violation and Proposed imposition of Civil Penalty ($50,000). The Notice of Violation addresses two issues: (1) A failure to implement a fire protection plan to ensure operability of the equipment in the 27-foot Emergency Switchgear Room should a fire occur in the 45-foot Emergency Switchgear Room; and (2) A failure to adequately demonstrate the effectiveness of corrective actions to resolve this problem. We agree with your assessment that although the violations did not result in a significant safety concern, they do represent a significant regulatory concern in that we failed to adequately demonstrate the ability to safely shutdown the plant in the event of a severe fire in the 45-foot switchgear room.
Our response to the Notice of Violation is provided in an attachment to this letter. This response details the causes of the violation, the corrective and preventative actions taken and planned, and the results achieved to date. Also attached is Baltimore Gas and Electric Company Check No. 01047528 in the amount of $50,000.
9608300107 960823 PDR ADOCK 05000317
/
G PDR
,g006
\\
\\
I Mr. J:m:s Li berm:n August 23,1996 Page 2 Should you have questions regarding this matter, we will be pleased to discuss them with you, i
Very truly yours, fn j
STATE OF MARYLAND
- TO WIT:
COUNTY OF CALVERT I hereby certify that on the 23hiday of
((11 MLLL 19M before me, the subscriber, a Notary Public of the State of Maryland in and for // /'d Lubtb (pr1Atta
. personally appeared Charles 11. Cruse, being duly sworn, and state's that he is Vice President [ff the Baltimore Gas and Electric Company, a corporation of the State of Maryland; that he provides trie foregoing response for the purposes therein set forth; that the statements made are true and correct to the best of his i
knowledge, information, and belief; and that he was authorized to provide the response on behalf of said 1
Corporation.
WITNESS mylland and Notarial Seal:
M
_)
4dQl L
Notary Public My Commission Expires:
b b
hh
'Date 8 CliC/CDS/bjd Attachments cc:
Document Control Desk,NRC
- 11. J. Miller, NRC D. A. Brune, Esquire Resident Inspector, NRC J. E. Silberg, Esquire R. I. McLean, DNR Director, Project Directorate I-1, NRC J.11. Walter, PSC A. W. Dromerick, NRC
i ATTACIIMENT (1)
NOTICE OF VIOLATION AND PROPOSED IMPOSITION OF CIVIL PENALTY
[NRC INSPECTION REPORT NOS. 50-317(318)/96-05]
L DESCRIPTION OF VIOLATIONS A.
Title 10 Code of Federal Regulations (CFR) Section 50.48(a) requires, in part, that each operating nuclear power plant have a fire protection plan that describes the means to limit fire damage to structures, systems, or components important to safety so that the capability to safely shut down the plant is ensured.
4 Contrary to the above, prior to a Nuclear Regulatory Commission (NRC) Electrical Distribution System Functional Inspection (EDSFI) in March-April 1992, the Baltimore Gas and Electric Company (BGE) fire protection plan was inadequate in that it did not include the means to limit fire damage to the safe shutdown equipment in the 27-foot elevation Emergency Switchgear Room (ESR) should a severe fire occur in the 45-foot ESR. Specifically, because the ventilation system for the switchgear room uses common i
ducting and fire dampers, a vere fire in the 45-foot ESR would disable the ventilation system for the 27-foot ESR. As a result, safe shutdown equipment in the 27-foot ESR would then be subjected to temperatures which would exceed those temperatures for
)
which the safe shutdown equipment was designed.
B.
License Condition 2.C.3 for Unit 1 (and License Condition 2.C.4 for Unit 2) requires that BGE maintain the administrative controls (quality assurance program) identified in i
4 Section 6 of the NRC's Fire Protection Safety Evaluation Report (SER) dated i
September 14,1979. Section 6 of that SER, Administrative Controls, states that the quality assurance program will be submitted at a later date. The Quality Assurance Program subsequently was submitted with BGE's letter, dated December 31, 1979, which states that BGE has implemented a program which meets the NRC's guidelines with specific exceptions. The NRCs guidelines were contained in Branch Technical j
Position APCSB 9.5-1, Appendix A.
Branch Technical Position APCSB 9.5-1, Appendix A requires, in part, that conditions adverse to fire protection, such as failures, malfunctions, deficiencies, deviations, defective components, uncontrolled combustible material and non-conformances are promptly identified, reported, and corrected.
Contrary to the above, from April 3,1992 until June 1996, conditions adverse to fire protection were not promptly corrected when the lack of protection for the safe shutdown equipment in the 27-foot elevation ESR noted in Violation A above was brought to the attention of BGE on April 3,1992, via an NRC EDSFI. Corrective actions which were taken were based on engineering judgment. Specifically, five 10,300 cubic feet per minute (cfm) fans were purchased (one for each ESR, plus one spare) to provide the estimated required flow of 8,000 cfm through the 27-foot and 45 foot ESRs. When subsequent calculations determined that 10,000 cfm was needed for adequate cooling, it was assumed that the 10,300 cfm fan would provide the 10,000 cfm cooling. These corrective actions were not verified by deta!!ed analysis or test until May 1996, and were, in fact, inadequate to satisfactorily reson c the condition, until June 1996, at which time the required and calculated cooling flow provided by the emergency fans was determined and verified.
I
r ATTACIIMENT (1)
I NOTICE OF VIOIATION AND I
PROPOSED IMPOSITION OF CIVIL PENALTY lNRC INSPECTION REPORT NOS. 50-317(318)/95-05]
l These two violations were classified in the aggregate as Severity Level III and a Civil Penalty of $50,000 imposed. Baltimore Gas and Electric Company accepts the Notice of Violation and the associated Civil Penalty.
l IL REASON FOR VIOLATION Prior to the EDSFI in March and April of 1992, the ESR ventilation systems were believed to be in compliance with 10 CFR 50.48(a). This belief was based on the actions that had been taken to comply l
with Appendix R requirements. Subsequent NRC documentation [an NRC SER dated September 14, 1979 and NRC Inspection Report Nos. 50-317(318)/84-04] substantiated the adequacy of support I
systems for post-fire safe shutdown, and indicated that the ESR air conditioning had been " satisfactorily l
addressed."
During the EDSFI, the NRC noted that the ESR Heating Ventilation and Air Conditioning (HVAC) was susceptible to single failures that could impair the ventilation to both ESRs. Since the 45-foot ESR contains HVAC ducting that supplies ventilation to the 27 foot ESR, a fire in the 45-foot ESR could destroy the switchgear in that room and isolate ventilation to the 27-foot ESR. With no ventilation, the l
27-foot ESR air temperatures would rise and eventually exceed the operating limits of equipment inside the room.
1 After the EDSFI, this issue was reviewed and an operability evaluation completed in July 1992. As a i
result of the operability evaluation, it was decided to provide a source of emergency backup ventilation l
to both ESRs to ensure temperatures would not exceed 150 F after a total loss of ventilation in either room. It was estimated that 8000 cfm air flow from the Turbine Building into the ESRs, at its maximum expected temperature of 110 F, was adequate to ensure ESR temperatures did not exceed 150 F after a l
loss of normal ventilation.
A dedicated 10,300 c m emergency backup fan for each room was procured, installed, and o
proceduralized. These fans were dedicated and locked in place, and strategies were developed on their use to ensure the fans had a dedicated power supply and would operate as designed. The fan's nominal rating of 10,300 cfm was thought to be adequate to support the estimated required air flow of 8,000 cfm through the room. Later in 1992, a formal calculation was performed to determine the temperature profile over time in the ESRs after a loss of ventilation. This calculation assumed an air flow through the rooms of 10,000 cfm. The resulting time vs. temperature profile indicated a temperature increase to l
150 F within 30 minutes followed by a decrease and stabilization at approximately 135 F over the long-l term. It was not recognized that the temperature profile from the temperature calculations was not bounded by a separate evaluation of equipment in the ESR. This evaluation determined that the equipment in the ESRs was operable at temperatures of up to 150 F for short durations followed by a long-term reduction to below 120 F. In cddition, the essumption of 10,000 cfm flow through the ESRs was not verified by performing flow tcsts to determine the actual flow rates the fans could deliver into the ESRs.
In late 1995, a self-assessment of Turbine Building ambient air temperatures was performed. This self-assessment concluded that local hot areas on the 27-foot Turbine Building elevation could reach 123 F, 2
A'ITACHMENT (1)
NOTICE OF VIOLATION AND i
t PROPOSED IMPOSITION OF CIVIL PENALTY INRC INSPECTION REPORT NOS. 50-317(318)/96-05]
not 110 F as used in the ESR room temperature calculations. The calculations were revised to
{
incorporate the new, higher Turbine Building maximum ambient temperature of 123'F. The new calculations concluded an early temperature peak of 150 F would occur in the ESR followed by a steady l
decrease to 145'F at 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. The assumption that the fans could deliver 10,000 cfm was not l
challenged and the new, more limiting ESR room temperature profile was not compared to the existing l
operability evaluation for equipment in the ESRs.
During a review of the 1992 EDSFI unresolved item in March 1996, the NRC questioned the ability of a l
10,300 cfm fan to deliver 10,000 cfm into through ESRs, as assumed in the calculations. The potential l
that this assumption was not conservative was acknowledged, and an additional fan was placed in service l
for each ESR until tests were performed to quantify the flows delivered into the ESRs by the fans. The j
tests showed that one fan delivered an air flow through the room of 5,155 cfm and two fans delivered an j
i air flow of 9,465 cfm through the room.
l Calculations were performed to determine if a flow rate of 5,000 cfm through the room could support l
equipment operability in the ESR.s. The new calculations found that an equilibrium temperature of 150 F would be reached after approximately 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> in the 27-foot ESR (138'F for the 45-foot ESR),
Since temperatures remained below 150 F for a long period, one fan was considered acceptable.
However, it was still not recognized that related evaluations used to support equipment operability, while
)
allowing temperatures to reach 150 F in the short-term, were conditional on the ESR room temperatures l
being reduced to below 120 F in the long-term. This problem was raised during a subsequent NRC l
inspection in May of 1996.
1 In July we revised the evaluation of ESR equipment operability. The evaluation concluded that i
equipment in the ESR's will remain operable for at least 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> at 150 F.
Even though subsequent analysis determined that one fan was adequate to ensure safe shutdown after a severe fire in the 45-foot ESR, the failure to adequately demonstrate this was a significant concern both l
to us and NRC. The underlying cause for this problem was a long-standing historical perception that Appendix R design standards are not rigorously defined and, therefore, less rigor was accepted for Appendix R design products than for other design products under Appendix B. As a result of the perception, Appendix R design products sometimes lacked adequate review and validation. In addition, l
management did not historically require a Appendix B design standards for Appendix R related issues.
Other causal factors related to this event include:
A.
Engineers and engineering supervisors were found to have a poor level of knowledge i
l concerning fire protection and Appendix R requirements.
B.
The engineers involved with this issue did not recognize and challenge assumptions in the ESR room temperature calculations.
C.
Management had an insufficient understanding of the issue and gave it less than j
adequate attention to ensure prompt and accurate resolution.
i l
3
_ _ ~ _
1 i
ATTACIIMENT (1)
NOTICE OF VIOLATION AND PROPOSED IMPOSITION OF CIVIL PENALTY
[NRC INSPECTION REPORT NOS. 50-317(318)/ % 05]
l D.
We had an overly defensive attitude when confronted with questions and concerns regarding this issue. When problems were pointed out, our reviews dealt only with identified weaknesses and failed to recognize wider problems and related issues.
E.
We tolerated a lack of closure regarding this issue which clouded ownership and made resolution more difficult, i
III.
CORRECTIVE STEPS TAKEN AND RESULTS ACHIEVED We have documented in our corrective action process the fact that the calculations performed to confirm i
the adequacy of ESR ventilation systems contained deficiencies and that when these deficiencies were raised by NRC, BGE reviews dealt only with identified weaknesses and failed to recognize wider problems.
We have reviewed the existing time temperature calculations, revised the equipment operability evaluation, and determined that no safety issue exists. We concluded that one fan was adequate for safe shutdown after a fire in the 45-foot ESR destroyed ventilation to the 27-foot ESR. However, to provide l
conservatism to our current plant configuration, we have maintained and proceduralized that two fans i
will be utilized for each ESR.
)
i We completed a planned one week Appendix R compliance overview evaluation by a qualified contractor. The purpose of this overview was to determine the progress of Appendix R upgrades and the status of Appendix R compliance at our site. Overall, indications were that Appendix R compliance was
)
demonstrated, but several areas were identified for improvement of documentation. These areas J
requiring improvement have been documented under the site corrective action program.
l l
IV.
CORRECTIVE ACTIONS TAKEN TO AVOID FURTHER VIOLATIONS On May 24,1996 a Technical Alert was issued in the Nuclear Engineering Department concerning this issue. The Technical Alert notified Nuclear Engineering Department personnel of the issue, its causes, and detailed the management expectations that will prevent similar future problems. A summary of these expectations is described below:
A.
Consider and document assumptions or judgment calls when preparing and reviewing calculations.
B.
Consider and maintain a broad focus when reviewing engineering products.
C.
Pay close attention and provide adequate documentation to design inputs and assumptions to ensure adequacy of results.
D.
Close issues in a timely manner.
<t ATTACIIMENT (I)
~
NOTICE OF VIOLATION AND PROPOSED IMPOSITION OF CIVIL PENALTY j
INRC INSPECTION REPORT NOS. 50-317(318)/96-05]
E.
Ensure crisis mode engineering gets thorough second reviews to ensure identification of any discrepancies introduced by schedule processes.
3 F.
Avoid defensiveness when dealing with critics of engineering products. Assume your critic has a valid issue or question and self-assess rather than defending the product.
Actions to brir.g long-standing Appendix R issues to closure have been accelerated. These include updating the interactive cable analysis, reviewing generic ventilation concerns, and reviewing implementation of past NRC generic correspondence.
We have accelerated the start of a planned independent self-assessment of our Appendix R program from spring 1997 to fall 1996. This self-assessment will use NRC Inspection Procedure IP-64150. The results of this self-assessment will be used to determine if further corrective actions are necessary for fire protection improvements. Other aspects of the fire protection programs will be addressed by a triennial fire protection audit to be conducted by the Quality Assurance Audits Unit later this year.
Appendix R training will be conducted for engineering personnel and engineering management by the end of the year. The focus of this training is to raise the level of knowledge and ownership concerning Appendix R among site engineers. This training will also discuss management expectations that the required design standards assoc.ated with Appendix R are the same as those for Appendix B related design products.
Iluman performance issues related to maintaining objectivity, awareness of standards of performance and recognizing the hazards of a defensive attitude are being addressed within the site's human performance improvement initiatives. Lessons learned from this effort will be discussed in future site wide leadership training.
V.
DATE WHEN FULL COMPLIANCE WILL BE ACHIEVED Full compliance was achieved upon our verification that a single emergency backup fan is adequate to maintain operability of equipment in the 27-foot ESR after a fire in the 45-foot ESR.
5