ML20039F121
| ML20039F121 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 12/16/1981 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20039F120 | List: |
| References | |
| NUDOCS 8201120018 | |
| Download: ML20039F121 (2) | |
Text
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NOS. 82 AND 81 TO FACILITY OPERATING LICENSE NOS. DPR-44 AND DPR-56 PHILADELPHIA ELECTRIC COMPANY PUBLIC SERVICE ELECTRIC AND GAS COMPANY DELMARVA POWER AND LIGHT COMPANY ATLANTIC CITY ELECTRIC COMPANY PEACH BOTTOM ATOMIC POWER STATION UNITS NOS. 2 AND 3 DOCKETS N05. 50-277 AND 50-278 Introduction By letter dated June 29, 1981, Philadelphia Electric Company (PECo or the licensee) requested changes to the Technical Specifications (TSs) appended to Facility Operating Licenses Nos. DPR-44 and DPR-56 for the Peach Bottom Atomic Power Station Units Nos. 2 and 3.
In the event of a loss of venti-lation in the main steam line tunnel area, the proposed changes would allow the increase in the trip setting for the main steam line tunnel exhaust duct temperature from 200 F to 250 F for up to thirty minutes.
Discussion When the reactor building ventilation system is inoperable, the temperature in the tunnel may rise above 200 F because the air is radiantiv heated by the main steam lines.
This high temperature air could then trigger the temperature sensors when ventilation is restored. To minimize inadver-tent plant transients when maintenance on the ventilation system is necessary, the licensee is proposing an increase in the trip setting for a thirty-minute period.
Evaluation Temperature sensors are used to detect small leaks from one to ten percent rated steam flow. Although the response time for detecting a steam leak is increased when the trip setpoint is raised, the adjustment neither enhances the course of the previously analyzed accident involving the complete severance of a main steam line nor decreases significantly a margin of safety. Our evaluation indicates that the amendments to the TSs are acceptable because of:
1.
the safety benefits in minimizing pressure and temperature transients caused by a reactor trip, 2.
the low probability of a stean line break occurring during the thirty-minute period of adjustment, and 8201120019 811216 '
PDR ADOCK 05000277 P
PB 2& 3 3.
the ability of tho temperature trip at the higher setpoint of 250*
to limit the radionuclide releases to levels below those consi-dered in the Final Safety Analysis Report for main steam line break releases.
The licensee shall take compensatory measures during the thirty-minute
, period by having an. operator monitor the control room indicators of the duct temperature so in the event of rapid increases (indicative of a steam line break), the operator shall promptly isolate the main steam line. The licensee's proposed TSs have been modified to include these We therefore conclude that the main steam line compensatory measures.
tunnel exhaust duct temperature trip setting ray be raised from 200 F to 250*F for up to thirty minutes when ventilation is being restored.
Environrental Consideration We have determined that the amendments do 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 rade this determination, we have further concluded that the amendments involve an action which is insignificant from the standpoint of environmental impact and, pursuant to 10 CFR 151.5(d)(4),
that an environmental impact statenent, or negative declaration and environ-mental inpact appraisal need not be prepared in connection with the' issuance of these amendments.
Conclusion We have concluded, based on the considerations discussed above, that:
(1) because the amendments do not involve a significant increase in the probability or consequences of accidents previously considered and do not involve a signi-ficant decrease in a safety margin, the arendaents do 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 Commist. ion's regulations and the issuance of these anendments will not be inimical to the common defense and security or to the health and safety of the public.
Dated:
December 16, 1981 l
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