ML20148T262
| ML20148T262 | |
| Person / Time | |
|---|---|
| Site: | River Bend  |
| Issue date: | 01/14/1988 |
| From: | Dick G Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20148T258 | List: |
| References | |
| IEIN-84-69, NUDOCS 8802030247 | |
| Download: ML20148T262 (5) | |
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t 7590-01 m
UNITED STATES NUCLEAR REGULATORY COMMISSION j
i GULF STATES UTILITIES COMPANY 1
. DOCKET NO. 50-458 l
OENIAL OF AMENOMENT TO FACILITY OPERATING 4
LICENSE AND OPPORTUNITY FOR HEARING The U.S. Nuclear Regulatory Commission (the Commission) has denied a request by the licensee for an amendment to Facility Operating License No.
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NPF-47 issued to Gulf States Utilities Company (GSU), for operation of the l
River Bend Station, Unit 1, located in West Feliciana Parish, Louisiana.
The notice of Consideration of Issuance of Amendment was published in the FEDERAL p
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REGISTER on September 9, 1987 (52 FR 34010).
1 The amendment, as proposed by the licensee, would modify Section 3.8.1.1 l
and Bases Section 3/4.8.1 of the River Bend Station, Unit 1, Technical j
i Spacifications by (1) deleting the requirements to demonstrate that the diesel f
generators (DGs) are operable by starting and running them loaded for a period l
of one hour when one or both offsite circuits are inoperable; and (2) modify 1
the current requirement that with one diesel generator inoperable "due to any j
cause other than preplanned preventative maintenance or testing "the remaining i
j diesel generators be demonstrated operable by starting and running loaded for j
a period of one hour.
The proposed amendment would delete the phrase "due to any cause other than preplanned preventative maintenance or testing" and add the phrase "as the result of a valid failure."
With regard to item (1), above, the licensee contends that adequate assurance of DG operability is maintained by the diesel generator testing P
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frequencies specified in the normal Technical Specification surveillance requirements.
In addition G5U references IE Information Notice No. 84-69 and Supplement 1 which warn against the danger of losing both the diesel generator and an of fsite power supply when they are operated in para)lel.
They are especially vulnerable in this mode to grid disturbances when the of fsite power system is in a degraded mode such as may be the case when an offsite power sources is lost.
In order to meet the present River Bend Technical Specifica-tion which requires loading of the diesel generators for a period of an hour when an offsite power source is lost, a diesel generator rust be operated in parallel with a remaining of fsite power source to achieve the required loading.
While the staf f agrees there is a danger of losing both the diesel generator and an offsite power supply when they are operated in parallel, the staff also concludes that it is necessary to provide additional assurance of diesel generator operability when an offsite power source is lost, since there is a greater likelihood of needing the diesel generators during this period.
The staf f therefore concludes that G5U's proposal to completely delete the opera-bility test requirement of the diesel generators when of fsite power supplies are lost is not acceptable.
With regard to item (2), above, the revised Action statements would require that with a diesel generator inoperable as a result of a valid failure the remaining diesel generators be demonstrated operable by starting and running loaded for a period of one hour, G5U's reason for proposing this change is to reduce the nu-ber of unneces-sary test starts on redundant diesel generators when the cause for inoperability on the original diesel generator is clearly not a common mode or generic type
3 failure which could also affect the availability of the redundant diesel genera-tors.
The licensee states that if a DG was discovered inoperable while in the standby service mode (i.e., no failure during a valid test) then the potential common mode / generic f ailure can be investigated and operability of the remaining diesel genera' tors verified without increased testing.
According to GSU's discussion, therefore, a valid failure is only one that occurs to a diesel generator while it is operating during a valid test, and any inoperability of a diesel generator discovered while it is in the standby mode would not be a valid f ailure and would not require testing of the redundant diesel generators under the proposed technical specification.
The staf f does not agree that inoperability of a diesel generator discovered while it is in standby versus inoperability as a result of a failure during operation forms a correct basis for determining the action to be taken with regard to whether the inoperability has common-mode / generic implications.
The same cause for inoperability could be discovered while the diesel generator is in the standby mode or undergoing a test based solely on circumstance, and yet in one case a test of the remaining diesel generators would be required and in the other the test would not be required.
Further, the testing of the remaining diesel generators is needed not only to verify there is no common mode problem but also to provide added assurance of the availability of the remaining onsite AC sources when one of them is lost.
The staf f concludes that this additional assurance is necessary regardless of whether the initial f ailure has common mode
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implications and further concludes that the proposed technical specification change is not acceptable.
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4 With regard to the above testing to provide added assurance of the avail-l l
ability of the reraining onsite AC sources, GW references IE Information l
l Notice 84-69 and supplement I which warn that when a diesel generator is j
operated connected to offsite or nonvital loads, the emergency pcwer system is not independent of disturbances on the nonvital and offsite power systems that l
can adversely af fect emergency power availability.
GSU states that assurance of availability is therefore lessened by a demonstration of operability requiring
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connection of the diesel generators to offsite and nonvital loads at a time
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when one other diesel generator is already inoperable.
The staff agrees there i
i is an increased danger of losing both the diesel generator and an offsite power i
supply when they are operated in parallel; however, the staff still concludes l
I that it is ne:essary to provide added assurance of the remaining onsite AC I
sources when one of them is lost, j
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By Februsry 22,19Mthe licensee may demand a hearing with respect to the l
I denial described above and any person whose interest may be af fected by this i
proceeding may fill a written petition for luave to intervene.
A request for a hearing or a petition for leave to intervene must be j
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filed with the Secretary of the Comission U.S. Nuclear Regulatory l
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j Comission, Washington. 0,C.
20555, Attention: Docketing and $ervice Branch, or may be delivered to the Comission's Public Document Room,1717 H Street, 4
I N.W., Washington, 0.C., by the above date.
A copy of any petition should also be sent to the Office of the General I
j Counsel, U. S. Nuclear Regulatory Comission, Washington 0.C.
20555, and to i
j Troy B. Conner, Jr., Esq., Conner and Wetterhahn,1747 Pennsylvania Avenue, I
1 N.w., Washington, D.C.
2 coo 6, attorney for the itcensee..
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i For further details with respect to this action, see (1) the application 1
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for amendment dated August 7,1987, and (2) the Commission's Safety Evaluation l
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forwarded to the licensee by letter dated January 14, 1988, which are f
available for public inspection at the Commission's Public Document Room,1717
[
H Street, NW, Washington, D.C.
20555, and at the Government Documents Department Louisiana State University, Baton Rouge, Louisiana 70803.
A copy i
of Item (2) may be obtained upon request addressed to the U.S. Nuclear Regulatory Commission, Washington, D.C.
20555, Attention:
Director, Division j
of Reactor Projects - III, IV, V and Special Projects.
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Dated at Bethesds, Maryland, this 14th day of January,1988.
a FOR THE NUCLEAR REGULATORY COMMISSION r
-Utf-1 George F. Dick, Jr.d Acting Project Director
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Project Directorate - IV Division of Reacter Projects - 111, i
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IV, V and Special Projects Office of Nuclear Reactor Regulation
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