NPL-97-0167, Application for Amends to Licenses DPR-24 & DPR-27, Eliminating Provisions for Operation of Units at Below 3.5% Rated Power W/Only One RCP
| ML20140D701 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 04/14/1997 |
| From: | Dante Johnson WISCONSIN ELECTRIC POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20140D705 | List: |
| References | |
| NPL-97-0167, NPL-97-167, NUDOCS 9704240058 | |
| Download: ML20140D701 (7) | |
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Wisconsin Electnc POWER COMPANY Point Beach Nuclear Plant (414) 755 2321 6610 Nuclear Rd., Two Rrvers, WI 54241 NPL 97-0167 April 14,1997 10 CFR 50.4 10 CFR 50.90 Document Control Desk U. S. NUCLEAR REGULATORY COMMISSION Mail Stop Pl-137 Washington, DC 20555 Ladies / Gentlemen:
DOCKETS 50-266 AND 50-301 TECHNICAL SPECIFICATIONS CIIANGE REOUEST 198 ELIMINATION OF PROVISIONS FOR AT POWER OPERATION WITH A MNGLE REACTOR COOLANT PUMP POINT BEACII NUCLEAR PLANT. UNITS 1 AND_2 1
l in accordance with the requirements of 10 CFR 50.4 and 10 CFR 50.90, Wisconsin Electric Power 1
Company, licensee for the Point Beach Nuclear Plant, hereby requests amendments to DPR-24 and DPR-27, licenses for Units 1 and 2, respectively. The requested amendments will incorporate changes to the plant Technical Specifications.
The purpose of the proposed amendments is to eliminate the provisions for operation of the units at below 3.5% rated power with only one reactor coolant pump. These provisions have been determined to be non-conservative. By eliminating these requirements, both reactor coolant pumps will be required to be in operation in order to maintain a unit critical.
Attached are: (1) A description of the existing and proposed license condition and the reason for the change; (2) A safety evaluation of the proposed change; (3) A no significant hazards determination, and (4) Marked-up Technical Specifications indicating the proposed changes.
It has been determined that the proposed changes (1) involve no significant hazards consideration, (2) do not result in a significant change in the types or significant increase in the amounts of any effluents released off site, and (3) there is no significant increase in individual or cumulative radiation exposure, and therefore meet the categorical exclusion criteria of 10 CFR 51.22 (c) (9).
In accordance with 10 CFR 51.22 (b) an environmental assessment or impact statement need not i
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. NPL 97-0167 -
April 14,1997 Page 2 be prepared. Alternatively, Wisconsin Electric Power Company requests.the Nuclear Regulatory Commission to issue and publish a finding of no significant environmental impact pursuant to L-10 CFR'51.21,51.32 and 51.35.
l-If you have any questions, please contact us.
Sincerely, Douglas F. Johnson
~ Manager Regulatory Services and Licensing cc:
NRC Regional. Administrator, Region Ill NRC Resident Inspector Public Service Commission Attachments Subs ribed to and sworn before me this
\\@ day of Q%
,1997 ChT, NMAM
' Notary Public, State of Wisc"ossin AAA M bkN My commission expires ( ll-d
DESCRIPTION AND REASON FOR PROPOSED CIIANGES
'TECIINICAL SPECIFICATIONS CIIANGE REOUEST 198 ELIMINATION OF PROVISIONS FOR AT POWER OPERATION WITil A SINGLE REACTOR COOLANT PUMP POINT BEACII NUCLEAR PLANT. UNITS 1 AND 2 Technical Specification 15.3.1.A provides the following provisions for at power operation with a single reactor coolant pump:
- 1. Coolant Pumps *
- a. When the reactor is critical, except for tests, at least one reactor coolant pump shall be in operation.
(1) Reactor power shall not be maintained above 3.5% of rated power unless both reactor coolant pumps are in operation.
(2) If either reactor coolant pump ceases operating, immediate power reduction shall be initiated under administrative control as necessary to reduce power to less than 3.5% of rated power.
(3) If both reactor coolant pumps cease operating and power is greater than 3.5% of rated power, but less than 10% of rated power, reactor shutdown will commence immediately and verify reactor trip breakers are opened within one hour.
The proposed changes will amend these provisions as follows:
- 1. Coolant Pumps *
- a. When the reactor is critical, both reactor coolant pumps shall be in operation.
(1) If one or both reactor coolant pump (s) cease operating the reactor shall be placed in hot shutdown within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
The existing Technical Specifications provisions listed above are non-conservative. During critical operation with one or both reactor coolant pumps idle or secured, temperature indication in the idle loop (s) will not accurately respond to changes in Reactor Coolant System conditions.1 his inaccurate response of temperature instrumentation in the idle loop may result in the non-functioning of protective functions, principally the Overtemperature AT and Overpower AT reactor trips in the time assumed in the Safety Analyses. Due to this, the required protection channels, served by the temperature instrumentation in the idle loop are not available in accordance with Technical Specifications Table 15.3.5-2, " Instrument Conditions for Reactor Trip." for these functions. The changes proposed will correct this inconsistency in Specifications. Bases changes are being made consistent with the proposed amendments.
The provision,"except for tests"is proposed to be eliminated. This is a conservative change in that it eliminates an exception to the specification. No testing is presently performed or required that would necessitate the securing of one or both reactor coolant pumps.
.in addition, we are proposing that the reactor be placed in hot shutdown within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> upon loss of one or both reactor coolant pumps when the reactor is critical. This is longer (six hours vs. one hour) than the time presently specified for the complete loss of flow when less than 10% but greater than 3.5% reactor power. However, the present specifications allow a power reduction to less than 3.5% power if a single reactor coolant pump ceases to operate with no time period specified for completion of the action. With reactor power less than 50%, loss of flow in one loop will not directly result in a reactor trip nor will a complete loss of flow when operating at less than 10% power. In order to allow for an orderly and controlled shutdown of the unit, six hours is i
specified for all conditions. Due to lower decay heat levels following shutdown when operating at reduced power and lower energy stored in the core, this time is appropriate for all conditions when i
one or both reactor coolant pumps cease to operate. This action time is based on operating experience and is also consistent with times specified in Specification 15.3.0 when in a condition prohibited or not covered by the Specifications i
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4 SAFETY EVALUATION TECIINICAL SPECIFICATIONS CIIANGE REOUEST 198 ELIMINATION OF PROVISIONS FOR AT POWER OPERATION WITII A SINGLE REACTOR COOLANT PUMP i
POINT HEACII NUCLEAR PLANT. UNITS 1 AND 2 Wisconsin Electric Power Company, licensee for Point Beach Nuclear Plant, Units 1 and 2, has requested amendments to Facility Operating Licensed DPR-24 and DPR-27, respectively. The purpose of the amendments is to eliminate the provisions within the Technical Specifications which allow operation of the units at up to 3.5% power with only one reactor coolant pump in operation.
Technical Specification 15.3.1.A.1 presently allows operation at up to 3.5% reactor power with an idle reactor coolant pump. The specification also requires shutdown only if both reactor coolant pumps cease operating when greater than 3.5% but less than 10% rated power.
During single loop operation, reactor coolant flow in the idle loop will occur in the reverse direction. Under these conditions, temperature instrumentation will not respond properly to changing plant conditions. For this reason, the temperature instrumentation in the idle loop is inoperable.
Temperature instrumentation, both Tao, and T m provide input to the Overtemperature AT and e
Overpower AT protection functions. Technical Specifications Table 15.3.5-2," Instrument i
Conditions for Reactor Trip," Items 5 and 6, require three out of the four channels of these protection features be operable during power operation. The inoperable temperature instrumentation in the idle loop renders two of the four required channels inoperable, a condition requiring placing the reactor in hot shutdown with eight hours. Thus, a conflict is created within the Technical Specifications allowing critical operation below 3.5% power with only one reactor coolant pump operating while concurrently requiring shutdown since only two of four Overtemperature AT and Overpower AT reactor trip channel are operable.
In order to eliminate this conflict, it is proposed that the restrictions and allowances on single reactor coolant loop operation be eliminated and replaced with the requirement that in order for the reactor to be operated critical and at power, both reactor coolant pumps be operable. Under this condition the protective features discussed above remain operable in accordance with Technical Specifications requirements.
l It is proposed that this requirement be applicable with the reactor critical during low power and power operating conditions. It is also proposed that should one or both reactor coolant pumps cease operating, the reactor be brought to the hot shutdown condition within six hours. Once shut down, operability restrictions on the reactor coolant pumps are determined by the Decay IIeat Removal requirements in Specification 15.3.1.A.3 Reactor trip on low reactor coolant flow is blocked when less than 10% power. Also, loss of flow in one reactor coolant loop when reactor power is greater than 10% power and 4 50% power, will not directly result in a reactor trip. Therefore, action is necessary to shutdown the reactor in an
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, orderly and controlled manner. Six hours, consistent with the Improved Standard Technical Specifications, NUREG 1431, is proposed. This time, based on operating experience, is reasonable for a safe and orderly shutdown.
l Specifications presently require a reactor shut down in less than one hour upon a loss of both i
reactor coolant pumps when greater than 3.5% power but less than 10% power. Due to the icwer i
stored energy in the core at low power the additional time to shut down the reactor does not i
present additional risk. In addition, by making the shutdown times the same for any cessation of-j reactor coolant pump operation, a potential source of confusion for the operators is eliminated, j
j Thus, an overall safety benefit is expected.
There is no change in facility effluents or any other radiological or non-radiological impact of the 4
facility and its environs. Therefore, the health and safety of the public is maintained by the proposed changes.
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NO SIGNIFICANT HAZARDS DETERMINATION
' TECHNICAL SPECIFICATIONS CHANGE REOUEST HH ELIMINATION OF PROVISIONS FOR AT POWER OPERATION WITH A SINGLE REACTOR COOLANT PUMP POINT BEACH NUCLEAR PLANT. UNITS 1 AND 2 Wisconsin Electric Power Company, licensee for the Point Beach Nuclear Plant, has evaluated the proposed amencLuents in accordance with tl.e requirement of 10 CFR 50.91(a)(1), against the standards in 10 CFR 50.92, and has determined that the operation of the Point Beach Nuclear Plant in accordance with the proposed amendments involves no significant hazards censideration. The evaluation against each of the standards in 10 CFR 50.92 follows:
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- 1. Operation of the Point Beach Nuclear Plant in accordance with the proposed amendments l
will not result in a significant increase in the probability or consequences of an accident previously evaluated.
The amendments proposed eliminate an inconsistency in the Technical Specifications in a conservative manner. The proposed changes ensure that required protection functions remain operable in all required modes of operation. Since the protection functions remain operable in accordance with existing Technical Specification requirements and serve to mitigate analyzed events no increase in the consequences of a previously analyzed accident results. The protective functions are not accident initiators and are maintained and tested in accordance with existing Technical Specification requirements, therefore the probability of a previously analyzed accident cannot increase. Therefore, operation of the Point Beach Nuclear Plant in accordance with the proposed changes does not result in an increase in probability or j
consequences of a previously analyzed accident.
- 2. Operation of the Point Beach Nuclear Plant in accordance with the proposed amendments will not create the possibility of a new or different kind of accident from any accident previously evaluated.
The proposed amendments restore consistency within the Technical Specifications thus ensuring the protections functions remain operable as required and the units are operated within the bounds of the existing safety analyses. Therefore, operation of the Point Beach Nuclear Plant in accordance with the proposed amendments does not result in a new or different kind of accident from any accident previously evaluated
- 3. Operation of the Point Beach Nuclear Plani a accordance with the proposed amendments does not involve a significant reduction in a margin of safety.
Margins of safety are defined by the bounds of the design and in the safety analyses performed for the Point Beach Nuclear Plant. The proposed amendments eliminate an inconsistency within the Technical Specifications and ensure the plant will respond as analyzed in the Safety Analyses. There is no physical change in the faci;;ty or operation. Therefore, operation of the Point Beach Nucicar Plant in accordance with the proposed amendments does not involve a reduction in safety.
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