ML20063L161
| ML20063L161 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 02/23/1994 |
| From: | Varga S Office of Nuclear Reactor Regulation |
| To: | BALTIMORE GAS & ELECTRIC CO. |
| Shared Package | |
| ML20063L166 | List: |
| References | |
| NUDOCS 9403040054 | |
| Download: ML20063L161 (5) | |
Text
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UNITED STATES NUCLEAR REGULATORY COMMISSION In the Matter of
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BALTIM0RE GAS AND ELECTRIC
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Docket No. 50-318 COMPANY
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(Calvert Cliffs Nuclear Power
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Plant, Unit No. 2)
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EXEMPTION l
I.
The Baltimore Gas and Electric Company (BG&E/ licensee) is the holder of Facility Operating License No. DPR-69, which authorizes operation of the Calvert Cliffs Nuclear Power Plant, Unit No. 2 (the f acility). The license provides, among other things, that the facility is subject to all rules, regulations and Orders of the U.S. Nuclear Regulatory Commission (the 1
Commission) now or hereafter in effect.
The facility is a pressurized water reactor located at the licensee's site in Calvert County, Maryland.
The licensee is implementing upgrades to the existing safety-related emergency diesel generators (EDGs) to increase their load capacity. The first part of this effort will be to upgrade Unit 1 EDG No. 11 during the upcoming Unit I refueling outage (RFO-ll). This outage commenced on February 8, 1994, and is scheduled to be completed in early May 1994. To support this initial 4
portion of the upgrades, the licensee has identified one temporary exemption required at this time. The exemption is specified below.
II.
The Code of Federal Regulations at 10 CFR Part 50, Appendix A, General Criterion-2 (GDC-2), requires that: Structures, systems, and components 9403040054 940223 PDR ADOCK 05000318 p
. important to safety shall be designed to withstand the effects of natural phenomena such as... tornadoes,... without loss of capability to perform their safety functions.
The licensee has requested the temporary exemption from GDC-2 because of the planned upgrade of the Unit 1 EDG No.11. The effort will require temporary removal of a steel missile door which will expose portions of the support systems of EDG Nos. 12 and 21. These EDGs are required to be operable to support the operation of Unit No. 2 and require protection from the potential effects of postulated missiles generated by natural phenomee.a. The licensee indicates that the steel missile door will be removed 4 times during RFO-11.
The licensee estimates that each of the missile door removals will last for about 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> which will result in a total removal time of about 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> during the scheduled 89 day outage.
The licensee is providing compensatory action to assure the safe operation of Unit No. 2 for the short periods of time during which the steel missile door will be removed. To encompass all severe weather conditions as defined in the plant site Emergency Resp 9nse Plan Implementing Procedures 3.0, 8, a concerted effort will be made to reinstall the missile door if a tornado or hurricane watch is issued or if sustained winds are predicted to be greater than 35 miles / hour at the site.
The only factor which would impede the reinstallation of the missile door would be to ensure the safety of the individuals performing the reinstallation.
Considering the existing design features and compensatory measure proposed by the licensee, the likelihood of damage to the exposed EDG support systems from postulated missiles generated by natural phenomena is minimal for e
. the short periods of time that the protective door will be removed. Also, based on the compensatory measure provided, reasonabie assurance exists that the ability to reinstall the missile door will be maintained prior to any severe weather which could result in airborne missiles. Therefore, there is reasonable assurance that the proposed GDC-2 exemption will present no undue risk to public health and safety.
III.
The Commission has deteit.ined, pursuant to 10 CFR 50.12(a), that special circumstances as set forth in 10 CFR 50.12(a)(2)(v) exist. The exemption would provide only temporary relief from the applicable regulation (GDC-2).
The exemption is requested for a specific time period after which the facility would again be in conformance with all the requirements of GDC-2. The licensee has made good faith efforts in considering alternatives to the exemption request and has concluded that the EDG upgrades can only be conducted without the subject exemption during a period when both units are shut down.
Based on the above and on review of the licensee's submittal, as sumarized in the Safety Evaluation, dated February
, 1994, the NRC staff concludes that the likelihood of unacceptable damage to the exposed portions of the Unit No. 2 EDG support systems due to weather-induced missiles during the short duration exposures occurring in the exemption period is low.
Based on the low probability of unacceptable events, coupled with the i
compensatory measure which the licensee has committed to, the NRC staff finds the proposed exemption from GDC ' o be acceptable.
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. IV.
Accordingly, the Commission has determined that, pursuant to 10 CFR 50.12, the subject exemption is authorized by law, will not present an undue risk to the public health and safety, and is consistent with the common defense and security. The Commission further determines that special circumstances, as provided in 10 CFR 50.12(a)(2)(v), are present justifying the exemption; namely, that the exemption would provide only temporary relief from the applicable regulations and that the licensee has made good faith efforts to comply with the regulations.
Therefore, the Commission hereby approves the following exemption:
Calvert Cliffs Nuclear Power Plant, Unit No. 2, may operate without conforming to the requirements of GDC-2 as they apply to the exposed portions of the support systems for EDG Nos.12 and 21 providing that the compensatory measure as described herein is in place for the period of the exemption.
Pursuant to 10 CFR 51.32, the Commission has determined that granting the above exemption will have no significant impact on the quality of the human environment (February 17, 1994, 59 FR 8033).
. The subject Unit No.1 EDG No.11 upgrade GDC-2 exemption if effective from its date of issuance through May 15, 1994.
FOR THE NUCLEAR REGULATORY COMMISSION t'
Varg,
Division of Reactor P o ects - I/II Office of Nuclear Reac or Regulation Dated at Rockville, Maryland, this 23rd day of February 1994 i
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