ML17139C751
| ML17139C751 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 12/19/1984 |
| From: | Eisenhut D Office of Nuclear Reactor Regulation |
| To: | PENNSYLVANIA POWER & LIGHT CO. |
| Shared Package | |
| ML17139C752 | List: |
| References | |
| NUDOCS 8412260101 | |
| Download: ML17139C751 (8) | |
Text
0 UNITED STATE OF AMEPICA NUCLEAR REG!JLATORY COMMISSION 7590-01 In the Hatter of Pennsylvania Power 5 Light Company Susquehanna Steam Electric Station Unit 2 Docket No.
50-3SS EXEMPTION The Pennsylvania Power and Light Co.
(PP8L/the licensee) is the holder of Facility License No.
NPF-22 which authorizes operation of Susquehanna Steam Electric Station Unit 2 (SSES-2) at power levels not in excess of 3293 megawatts thermal.
The facility is a Boiling Mater Reactor located at the licensee's site in Luzerne County, Pennsylvania.
The license provides, among other things, that it is subject to all rules, regulations, and Orders of the Commission now or hereafter in effect.
Inerting the containment for the SSES-2 plant is required by 10 CFR 50.44 (revised).
In 10 CFR 50.44, "Standards for combustible gas control system in light-water-cooled power reactors,"
Section 50.44(c)(3)(i) states that, "Effective May 4, 19S2 or 6 months after initial criticality, whichever is later, an inerted atmosphere shall be provided for each boiling light-water nuclear power reactor with a Mark I or Mark II type containment."
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LV %A Since SSES -2 achieved its initial criticality on May 7, 1984, the plant is required to be inerted by November 8, 1984, per the 10 CFR 50.44 requirement set forth above.
On October 27, 1984 SSES-2 ivas shut-down for a pre-commercial outage scheduled to last thru the end of December 1984.
Prior to start-up presently scheduled for January 1985, the licensee needs an exemption so it may continue operating the plant with a non-inerted contain ent during the balance of the initial startup test program.
The exemption from the regulation is required in order to complete the balance of the power ascension test program (PATP) in accordance with the licensee's test plan.
The licensee's test plan is based on maintaining the containment in a non-inerted condition until after completing the 100'X rated thermal trip test, a condition which normally would be. expected to occur within about 120 effective full power days of core burn-up.
Ho changes are being made in the maximum full power days of core burn-up normally expected before inerting is required.
In fact to assure this, the maximum expected value of 120 effective full power days is made part of the proposed action.
The licensee's PATP schedule has not been maintained as originally planned.
This has resulted in a simple stretch out of the time required to complete all post criticality PATP tests.
It is advantageous to operate the reactor without inerting during the
- PATP, as an uninerted containment would permit unscheduled inspections or identification of possible problems important to safety during this period.
The anticipated high frequency of containment entries during the PATP period
I and the required deinerting and re--inerting time (about 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />) would tend to discourage early and frequent containment entries for identifying and correcting any potential safety problems before they become serious safety problems.
The NRC staff has evaluated the licensee's current schedule for completing the preoperational test program and believes that to now require inerting before the PATP tests have been completed could result in less assurance of
- safety, because of the added time and/or decreased ability to directly examine and evaluate components and systems inside containment while the PATP tests are under way.
Completing the PATP tests with an uninerted containment then would reduce the likelihood of development of an event requiring protective safety actions both during the period of exemption and later.
Because of the low level of fission product inventory during the PATP period, (less than 42 effective full power days (FPD) at present increasing to the maximum of only 120 EPD) and the short duration anticipated for the exemption (about 2-3 weeks of remaining PATP testing after start-up),
there is an extremely low likeli-hood that the inerting system would be required.
Based on the information provided by the l.icensee and the staff's assurance that the remainder of the PATP tests will be performed in essen-tially the same manner as originally planned with respect to the magnitude
A and duration of power levels for each remaining PATP test, the HRC stai.
concludes that there will be no increase in the risks of operation through completion of the PATP tests with the proposed limited exemption regarding initial inerting over the risks that were contemplated for the duration of the PATP tests at the time the plant was licensed.
Therefore, since there 5
is no perceived increased risk by the mere fact of extending the time allowed for completion of the PATP tests under uninerted conditions, the NRC staff finds that operation would be as safe under the conditions pro-posed by the exemption as it would have been had the tests been complete) in the shorter calendar time of six months after initial criticality.
The inerting requirement resulted from a staff judgement that the safety benefits attributable to having an inerted containment during normal opera-tions outweighed the associated disadvantages.
This judgement does not prevail during the PATP because of the need for frequent containment entries for inspection and surveillance purposes.
The staff finds that an exemption from 10 CFR 50.44, paragraph (c)(3)(i) is acceptable.
IV.
Accordingly, the Commission has determined that, pursuant to 10 CFR
- 50. 12 the exemption is authorized by law, will not endanoer life or property or the common defense and security and is otherwise in the public interest.
Therefore, the Commission hereby grants the exemption as follows:
"An exemption is granted from the requirements of 10 CFR 50.44 Paragraph (c)(3)(i) until either the required 100 percent rated thermal power trip startup tests have been completed or the reactor has operated for 120 effective full power days, whichever is earlier."
Pursuant to 10 CFR 51.32, the Commission has determined that'he issuance of the exemption will have no significant impact on the environment (49 FR 4862lI.
A copy of the Commission's Safety Evaluation dated Dec. lS 1894 related to this action is available for public inspection at the Commission's Public 1
Document
- Room, 1717 H Street, N. W., Washington, D.C. and at the Osterhout Free Library, Reference Department, 71 South Franklin Street, Wilkes-Barre, Pennsylvania 18701.
This Exemption is effective upon issuance.
FOR THE NUCLEAR REGULATORY COf<MISSION Pp f.l2;inane S1821Vd bY p~geU g. Ej.seahQ5 Darrell G. Eisenhut, Director Division of Licensing, NRR Dated at Bethesda, Maryland this 19th day of December 1984.
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