ML19276E890
| ML19276E890 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 02/27/1979 |
| From: | Ziemann D Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19276E886 | List: |
| References | |
| NUDOCS 7903210582 | |
| Download: ML19276E890 (2) | |
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9 7590-01 UNITED STATES NUCLEAR REGULATORY COMMISSION DOCKET NO. 50-237 COMMONWEALTH EDIS0N COMPANY NOTICE OF ISSUANCE OF AMENDMENT TO PROVISIONAL OPERATING LICENSE The U. S. Nuclear Regulatory Commission (the Commission) has issued Amendment do. 40 to Provisional Operating License No. DPR-19, issued to the Commonwealth Edison Company (the licensee), which revised the Technical Specifications for operation of Unit No. 2 of Dresden Nuclear Power Station (the facility) located in Grundy County, Illinois.
The license amendment is effective as of its date of issuance.
The amendment revises the Technical Specifications to permit operation of the reactor for a period of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from 1:00 p.m. on February 4,1979, with a negative pressure of 0.2 inches of water in areas of the Reactor Building below the refueling floor.
The application for the amendment complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations.
The Commission has made appropriate findings as required by the Act and the Commission's rules and regulations in 10 CFR Chapter I, which are set forth in the license amendment.
Prior public notice of this amendment was not required since the amendment does not involve a significant hazards consideration.
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. We have further concluded that the proposed operation is in the public interest because of possible load shedding in the area that might be required if Dresden Unit No. 2 is not available during this 24-hour period.
The NRC staff has determined that an additional measure of protection will be afforded the public by the continuous operation of the standby gas treatment system during the period that this specification is in effect.
We have discussed this action with CECO and they have agreed to operate the system continuously.
We have modified the proposed specification to require that the negative pressure be maintained cor.t inu ou sl y.
In evaluating the above considerations, we have concluded that the proposed change, as modified by the NRC staff, is acceptable.
Environmental Consideration We have determined that. the amendment does not authorize a change in effluent types or total amounts nor an increase in power level and will not result in any significant environmental impact.
Having made this determination, we have further concluded that the amendment involves an action which is insignificant from the standpoint of environmental impact and pursuant to 10 CFR 551.5(d)(4) that an environmental impact statement or negative declaration and environ-mental impact appraisal need not be prepared in connection with the issuance of this amendment.
Conclusion We have concluded, based on the considerations discussed above, that:
(1) because the amendment does not involve a significant increase in the probability or consequences of accidents previously considered and does not involve a significant decrease in a safety margin, the amendment does not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such activities will be conducted in compliance with the Commission's regulations and the issuance of this amendment v;ll not be inimical to the common defense and security or to t6e health and safety of the public.
Date: February 27, 1979 1.
The Reactor Building air space has been isolated from the refueling floor air space by temporary barriers.
With these barriers in place, CECO is able to maintain a negative pressure of 0.2 inches of water in the Reactor Building exclusive of the refueling floor by operating the standby gas treatment system.
2.
The secondary containment performance requirement (0.25 inches of water negative pressure) was selected to prevent leakage from the Reactor Building caused by localized areas of wind-induced negative pressure.
These areas are located in the upper corners of the lee side of the Reactor Building refueling floor during high winds.
These areas are now isolated from the Reactor Building volume by temporary barriers.
We have determined that a negative pressure of 0.2 inches of water in the balance of the Reactor Building (excluding the refueling floor) is adequate to prevent exfiltration from the building.
3.
The accident analysis for Dresden assumes that accidents occur under stagaant meteorological conditions with a low wind velocity.
The current wind conditions present at Dresden Station involve 10 to 15 mile per hour winds with turbulent flow.
4.
Most of the primary containment penetrations are located in the Reactor Building below the refueling floor and do not communicate directly with the refueling floor air space.
Therefore, in the event of a LOCA, the leakage through the containment penetrations (a) will be contained within the portton of the Reactor Puilding secondary containment that maintains its integrity and (b) will be processed through the standby gas treatment system.
5.
CECO has committed to stop all fuel handling and cask handling activities on the refueling floor until secondary containment integrity is restored by repairing the breach in the Reactor Building 2.all above the refueling floor level.
6.
CECO has ind cated that they are unable to purchase sufficient replacement power to prevent system voltage reduction and possible subsequent load shedding in the area.
We have considered the preceding factors and have concluded that CECO's procedure to maintain Reactor Building integrity (as previously described) provides an equivalent level of protection against the exfiltration of airborne radioactive material should a LOCA occur within the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> that this Technical Specification is in effect.