ML20073F679
| ML20073F679 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 04/24/1991 |
| From: | Fay C WISCONSIN ELECTRIC POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20073F685 | List: |
| References | |
| CON-NRC-91-053, CON-NRC-91-53 VPNPD-91-134, NUDOCS 9105030001 | |
| Download: ML20073F679 (4) | |
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Wisconsin Electnc POWER COMPANY 231 W MicNocoo Ba 2046. wwouwa wi 53201 (M4) 221-2345 VPNPD-91-134 10 CFR 50.59 NRC-91-053 10 CFR 50.90 10 CFR 50.4 April 24, 1991 U. S. NUCLEAR REGULATORY COMMISSION Document Control Desk Mail Station F1-137 Washington, D.
C.
20555 Gentlemen:
DOCKETS 50-26(. AND 50-301 TECHNICAL SPECIFICATION CHANGE REOUEST 144 j
CONDENSATE STORAGE TANK LEVEL REQUIREMENTS POINT BEACH NUCLEAR PLANTS, UNITS 1 AND 2 In accordance with the requirements of 10 CFR 50.59(c), 50.90, and 50.4, Wisconsin Electric Power Company (Licensee) hereby.
requests amendments to Facility Operating Licenses DPR-24 and DPR-27 for Point Beach ~ Nuclear Plant,. Units 1 and 2.respectively.
The requested amendments consist of revisions to Technical Specification 15.3.4.A.3 and the associated basis.
The proposed changes would increase the required minimumivolume of-water 1
available in the Condensate Storage Tanks (CST's) from 10,000 to 13,000 gallons per unit and provide'the basis for maintaining l
this minimum inventory.
Marked-up Technical: Specification pages with the proposed-changes included are attached.
On April 17, 1989,'we submitted our response to the station blackout rule, 10 CFR 50.63, " Loss of All Alternating Current.
Power."
In that response, we maintained that-the existing-Technical Specification requirement.of 10,000 gallons of water per unit in the CST's, along with the initial' steam generator
. water inventory, was sufficient to maintain steam generator decay heat removal capability, using auxiliary feedwater during-the one-hour period following a loss-oflall AC power nece'ssary to.
align the alternate.AC (AAC) source.
Service water is available as a source of water to feed steam generators.following restoration of power from the AAC. source.- A calculation.was-j performed supporting-our position-and.is1 maintained on1 file.
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'NRC Document Control Desk i
April 24, 1991 j
Page 2 In the NRC staff's Safety Evaluation Report (SER) dated
)
October 3, 1990, addressing our conformance to the rule, the staff recommended that we increase the minimum water volume;
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j requirement for the CST's to 13,000 gallons per unit.
This was based on the conclusion presented in the Technical Evaluation 1 1
Report attached to the SER that.the presently required 10,000 gallon limit may not be sufficient,-considering other-operator priorities at one hour after onset of-a station blackout.
This j
one-hour time frame is based on the time limit in the rule for
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having an AAC source available.
While the 10,000. gallon l
requirement is technically adequate for accident analysis, we i
agree that increasing the required volume to 13,000 gallons per-unit will afford operators additional time to take the necessary corrective action.
We, therefore, areLrequesting a change to Technical Specification 15.3.4.'A.3 to require a minimum CST water inventory of 13,000 gallons'of water per. unit.
We have also
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proposed a change'to the " Bases" for Technical' Specification Section 15.3.4 to indicate _this CST level _is adequate to maintain a ut.!t in hot shutdown condition for at least one hour following a loss of all AC power.
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Wo have evaluated these proposed changes, in accordance'with the requirr,ments_of 10 CFR 50.91(c), against the standards. contained i
in 10 CFR 50.92 and have determined that operation of-the Point l
Beach Nuclear Plant units.in accordance with the proposed' anendments does not' result in a significant hazards j.
censideration.
Accidents evaluated for Point Beach Nuclear Plant censidered in.our. determination.of no significant hazards include i
Loss of All AC Power to the Auxiliaries', Loss of. External l
Electrical Load, Loss of Normal Feedwater,-Steam Generator Tube l'
Rupture. and Small Break LossLof Coolant Accidents._ Our evaluation against each of the~criterianof 10 CFR 50.92 and basis' for this conclusion follow:
Criterion 1 operation.of a facility in accordance;with a proposed amendment will not present'a significantihazards:
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consideration if-it-does not1 involve a.significant= increase in the_ probability or consequences of-an accidentLpreviously-evaluated.: The proposed change increases the requiredfwater inventory in the condensate _ storage tanks and provides the basis for the required inventory.. The. increased: inventory
'provides thel operator with additional?timelin_which to take action inL the event of a: loss of all' AC power and anytime:
there is a demandcfor auxiliary feedwater," including the; 9
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'NRC Document Control Desk April 24, 1991 Page 3 above-referenced accidents.
Maintaining a greater water volume in the CST's also provides the capability to remove a greater total quantity of decay heat prior to additional operator action being required.
Increasing the total quantity of decay heat energy that can be removed prior to operator response being required does not increase the probability of an accident previously evaluated and may decrease the overall. accident consequences.
Criterion 2 Operation of a facility.in accordance with a proposed amendment does not result in a significant hazards consideration if it cannot' create the possibility of a new or different kind of accident from any previously evaluated.
The required minimum inventory in the condensate storage tanks is increased.
The corresponding basis is clarified to indicate this inventory is sufficient for at least one hour of operation in hot shutdown following a loss of all AC power.
There is no change to the auxiliary feedwater system or its operation or other physical change to the. facility and its operation.
Therefore, a new or different kind of accident from any previously evaluated-cannot result.
Criterion 3 operation of a facility in accordance with a proposed amendment does not result in-a significant hazards.
consideration if it does not resultfin a significant reduction in a margin of safety.
By increasing:the required water inventory in-the condensate storage tanks, a margin of safety is increased.
The operator has additional time to evaluate options and implement the. preferred method to i -
insure a continued source of. auxiliary feedwater for decay heat removal, depending on the situation.at hand.
The operator also.has additional time to respond to.the accident before maintaining auxiliary'feedwater becomes alpressing Concern.
t We, therefore, conclude that these proposed changes do not result in a significant hazards consideration.-
We request that these amendments be issued by July.31', 1991.
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'NRC Document Control Desk l
April 24, 1991 Page 4 l
l Please contact us if you have any questions concerning the proposed amendments or 10 CFR 50.91 ovaluation.
Very truly yours, Y/
(q u C. W. Fay Vice President Nuclear Power Attachments Copies to NRC Regional Administrator, Region III NRC Resident Inspector Subscribed and sworn to before me this
>4A day of O edi, 1991.
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Notary Public, State o'f" Wisconsin My Commission expires 5-2 ? -9 4.
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