ML20210C369
| ML20210C369 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 09/12/1986 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20210C346 | List: |
| References | |
| NUDOCS 8609180320 | |
| Download: ML20210C369 (3) | |
Text
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UNITED STATES
[
g NUCLEAR REGULATORY COMMISSION
- j WASHINGTON, D. C. 20555 l
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NOS.121 AND 125TO FACILITY OPERATING LICENSES 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
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DOCKETS NOS. 50-277 AND 50-278
1.0 INTRODUCTION
By letter dated May 23, 1985, Philadelphia Electric Company (licensee) transmitted a Peach Bottom Technical Specification change request. The licensee proposed (1) to raise the hydrogen concentration limit down-stream of the off-gas recombiners to 4 percent by volume from the cur-rent 2 percent, (2) to lower the number of hydrogen analyzers required to be operational during power operation to one from the currently required two, and (3) to revise the definition of " Alteration of the
- l Reactor Core"' consistent with the Standard Technical Speci.fications.
2.0 EVALUATION The licensee has replaced the Unit 2 high pressure (200 psig) com-pressed off-gas storage system with a low pressure (1 psig) charcoal delay system. Specifically, the licensee has (1) removed the mechanical compressors, the precooler/ moisture separator, and the jet compressors, (2) converted the holdup pipe (5 feet in diameter and 470 feet long) into a charcoal adsorber bed, and (3) installed a new condenser / moisture separator, new jet compressors, and glycol cooling equipment. The same modifications are planned for the Unit 3 off-gas system in the next refuelingoutage(late 1987).
The original high pressure compressed off-gas storage system was not designed to withstand the effects of a hydrogen explosion. Hence, the current Peach Bottom Technical Specifications (1) require two independent hydrogen analyzers to be operational, (2) limit the hydrogen concen-tration downstream of the recombiners to 2 percent by volume, and (3) allow continuous operation of up to.14 days in the event that one of the two hydrogen analyzers becomes inoperable, provided that grab samples are taken and analyzed every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
8609180320 860912 PDR ADOCK 05000277 P
-2 The licensee states in their letter dated January 31, 1986, in response to additional staff questions that with the modified off-gas systems, all portions of the Unit 2 off gas system are designed to withstand the effects of a hydrogen explosion. The licensee further states that piping and components in the off-gas system have been analyzed in accordance with the methodology provided in Appendix C. " Acceptable h thods of Design to Contain Detonation" of ANSI /ANS 55.4, " Gaseous Radicactive Waste Processing Systems for Light Water Rea: tor Plants (1979)". The oft-gas system planned for Unit 3 will satisfy the same standards upon completion late in 1987.
In view of the above, we accept the following revised Liniting Conditions for Operation (LCO) which the licensee preposed for incorporation into the Peach Bottom Technical Specification Section 3.8.C,6:
3.8.C.6 The concentration of hydrogen downstream oi the rec:m-hiner: shall be licited to less than or equal to 4% by volume.
a.
With the concentration of hydrogen downstream of the recombiner greater than 4%, restore the concentration to within the limit within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.
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b.
Ext.ept as specified in 3.8.C.6.c, one hydrogen monitor down-stream of the recombiner shall be operable whenever the main condenser evacuation system is in operation.
c.
With the numoer of hydro' gen monitors operable less than re-quired, operation may continue for up to 30 days provided grab samples are taken and analyzed every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> whenever the main condenser evacuation system is in operation.
The above revised LC0 is consistent with GE/BWR-5 Standard Technical
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Specifications for off-gas systems designed to withstand the effects of a hydrogen explosion. The_off-gas system modification made is also in accordance with Standard Review Plan Section 11.3.
The licensee also proposed a revision to the current TSs involving the definition for " Alteration of the Reactor Core". Tf'e proposed revision would clarify the definition in the current TSs to reflect the staff's position and guidance in this matter. The staff's ~ intent as manifested in the Standard Technical Specifications (NUREG-0123, Rev. 3, Standard Technical Specification's for General Electric Boiling Water Reactors) is e
that the definition of " Alteration of Reactor Core" or " pore Alter-ation" should apply only when the vessel head is removed and fuel is in the vessel. The proposed TS change would provice cierttict. tion of this fact by adding the following words (noted here by underlining) to the t
current " Alteration of the Reac. tor Core" definition:
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... " Alteration of the Reactor Core - The act of moving any component in the regiom above the core support plate, below the upper grid and within the shroud with the vessel head removed and fuel in the vessel."
On the bases of the above evaluation, we find that the specific requested amendment changes addressed by the staff at this time are acceptable.
3.0 ENVIRONMENTAL CONSIDERATION
These amendments change a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. We have determined that the amendments involve no significant increase in the amounts, and no signficant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that these amendments involve no significant hazards consideration and there'has been no public comment on such finding.
Acccrdingly, these amendments meet the eligibility criteria for categorical exclusion sat forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.
4.0 CONCLUSION
We have concluded, besed on the considerations discussed above, that:
(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (2)'such activities will be conducted in compliance with the Commission's regulations and the issuance of these amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
J.
w
- i. Gears Dated: September 12, 1 sod
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