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{{Adams
#REDIRECT [[ET 12-0018, License Amendment Request to Increase Voltage Limit for Diesel Generator Load Rejection Surveillance Requirement]]
| number = ML12272A279
| issue date = 09/19/2012
| title = License Amendment Request to Increase Voltage Limit for Diesel Generator Load Rejection Surveillance Requirement
| author name = Broschak J
| author affiliation = Wolf Creek Nuclear Operating Corp
| addressee name =
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000482
| license number =
| contact person =
| case reference number = ET 12-0018
| document type = Letter, License-Application for Facility Operating License (Amend/Renewal) DKT 50
| page count = 17
| project =
| stage = Request
}}
 
=Text=
{{#Wiki_filter:W$P.LF CREEK'UCLEAR OPERATING CORPORATION September 19, 2012 John P. Broschak Vice President Engineering ET 12-0018 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555
 
==Subject:==
Docket No. 50-482: License Amendment Request to Increase Voltage Limit for Diesel Generator Load Rejection Surveillance Requirement Gentlemen:
Pursuant to 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," and 10 CFR 50.91, "Notice for public comment; State consultation," Wolf Creek Nuclear Operating Corporation (WCNOC) hereby requests an amendment to Renewed Facility Operating License No. NPF-42 for the Wolf Creek Generating Station (WCGS). The proposed amendment increases the voltage limit for the emergency diesel generator (DG) full load rejection test specified by Technical Specification (TS) 3.8.1, "AC Sources - Operating,"
Surveillance Requirement (SR) 3.8.1.10.
Attachments I through III provide the Evaluation, Markup of TSs, and Retyped TS pages, respectively, in support of this amendment request.
It has been determined that this amendment application does not involve a significant hazard consideration as determined per 10 CFR 50.92, "Issuance of amendment." Pursuant to 10 CFR 51.22, "Criterion for categorical exclusion; identification of licensing and regulatory actions eligible for categorical exclusion or otherwise not requiring environmental review," Section (b),
no environmental impact statement or environmental assessment needs to be prepared in connection with the issuance of this amendment.
This amendment application was reviewed by the Plant Safety Review Committee.                  In accordance with 10 CFR 50.91, "Notice for public comment; state consultation," Section (b)(1),
a copy of this amendment application, with attachments, is being provided to the designated Kansas State official.
Sood P.O. Box 411 / Burlington, KS 66839 / Phone: (620) 364-8831 An Equal Opportunity Employer M/F/HCNET                  U
 
ET 12-0018 Page 2 of 3 WCNOC requests approval of this license amendment request prior to August 1, 2013.
It is anticipated that the license amendment, as approved, will be effective upon issuance and will be implemented within 90 days from the date of issuance. This letter contains no commitments. Please contact me at (620) 364-4085 or Mr. Gautam Sen at (620) 364-4175 for any questions you may have regarding this application.
Sincerely, JonP. Broschak JPB/rlt Attachments:    I      Evaluation II      Proposed Technical Specification Changes (Mark-up)
III    Revised Technical Specification Pages cc:    B. J. Benney (NRC), w/a E. E. Collins (NRC), w/a T. A. Conley (KDHE), w/a N. F. O'Keefe (NRC), w/a Senior Resident Inspector (NRC), w/a
 
ET 12-0018 Page 3 of 3 STATE OF KANSAS                )
SS COUNTY OF COFFEY )
John P. Broschak, of lawful age, being first duly sworn upon oath says that he is Vice President Engineering of Wolf Creek Nuclear Operating Corporation; that he has read the foregoing document and knows the contents thereof; that he has executed the same for and on behalf of said Corporation with full power and authority to do so; and that the facts therein stated are true and correct to the best of his knowledge, information and belief.
SUBSCRIBED and sworn to before me this          qz    y of Se    2012.
Notary Publ*            i-
                                                                            -d GAYLE SHEPHEARD1 E&    Notary Public - tate of Kansasj Expiration Date  "/2-'/4/,A.o
[My Appt. Expires  "7/.Z
 
Attachment I to ET 12-0018 Page 1 of 10 EVALUATION 1.0   
 
==SUMMARY==
DESCRIPTION 2.0    DETAILED DESCRIPTION 2.1    Proposed Technical Specification Changes 2.2    Reason for Proposed Amendment
 
==3.0    BACKGROUND==
 
==4.0    TECHNICAL EVALUATION==
 
==5.0    REGULATORY EVALUATION==
 
5.1    Significant Hazards Consideration 5.2    Applicable Regulatory Requirements/Criteria 5.3    Precedent
 
==6.0    ENVIRONMENTAL CONSIDERATION==
 
==7.0    REFERENCES==
 
Attachment I to ET 12-0018 Page 2 of 10 EVALUATION 1.0     
 
==SUMMARY==
DESCRIPTION The proposed amendment increases the voltage limit for the diesel generator (DG) full load rejection test specified by Wolf Creek Generating Station (WCGS) Technical Specification (TS) 3.8.1, "AC Sources - Operating," Surveillance Requirement (SR) 3.8.1.10.
2.0      DETAILED DESCRIPTION 2.1      Proposed TS Changes The proposed amendment would increase the TS SR 3.8.1.10 limit for maximum voltage following a DG full load rejection from a value of -<4784 volts (V) to a value of -<4992 V.
2.2      Reason for Proposed Change Following repairs to the 'B' DG alternator field ground on February 22, 2012, a full load rejection test was performed to verify that the alternator repairs were successful and that the DG could endure a full load rejection without a fault occurring. Since the purpose of the test was not to test the governor engine response, thus the load rejection was performed in droop mode instead of the isochronous mode used to satisfy TS SR 3.8.1.10. Although a fault did not occur, the peak voltage during the load rejection test exceeded the TS SR 3.8.1.10 maximum voltage limit of 4784 V.
Wolf Creek Nuclear Operating Company (WCNOC) has reviewed historical data and determined that although the excitation system is performing as expected, the review determined that the cause appears to be related to increased grid voltage at the outset of the test. The current maximum voltage limit is based on approximately 115% of the nominal grid voltage of 4160 V. The proposed change increases the SR 3.8.1.10 maximum voltage limit to account for increases in grid voltage. A higher voltage limit is needed to accommodate normal variations in grid conditions that cannot be controlled by WCGS personnel. These variations in grid conditions are illustrated by the following table showing the conditions that existed for previous performances of DG full load rejection testing.
DG          Reason for Test          Initial      Peak            Initial to Peak Voltage      Voltage        Voltage Difference A              RF14                4235          4731                  496 B              RF14                4197          4742                  545 A              RF15                4202          4694                  492 B              RF15                4276        4750                  474 A              RF16                4192          4701                  509 B              RF16                4281          4768                  487 A              RF17                4151          4731                  580 B              RF17                4206          4726                  520 B              RF18                4306        4850(1)                544 B            RF18 PMT(2)            4235          4732                  497 B          02/22/2012(3)            4346      4811.6(1)              465.5 B          02/25/2012(2)          4269.1      4743.7                474.6 A          03/08/2012(3)          4249.9      4673.2                423.3
 
Attachment I to ET 12-0018 Page 3 of 10 Notes:
(1) Maximum voltage limit not met.
(2) SR 3.8.1.10 re-performed after grid voltage was lowered.
(3) Post maintenance test following repairs to alternator field ground.
The table data shows that the voltage difference between the initial voltage and the peak voltage was less than the 624 V, which is the difference between the nominal voltage of 4160 V and the current maximum voltage limit of 4784 V, including the surveillance tests in which the maximum voltage limit was not met. The data also shows the two surveillance tests in which maximum voltage limit was not met were also the two test with the highest initial voltage values.
A correlation of the data indicates that if the initial voltage is at the upper limit of the steady state acceptable voltage limit (4320 V, as specified in various SRs), the maximum voltage limit will not be met during the performance of the full load rejection test.
As described below, a higher voltage limit would continue to fulfill the basis for the voltage criteria. Accordingly, WCNOC is proposing a license amendment to increase the voltage limit for the DG full load rejection surveillance test.
 
==3.0      BACKGROUND==
 
3.1      System Description The Class IE AC System contains standby power sources which provide the power required for post-accident and post-fire safe shutdown in the event of a loss of the preferred power sources.
The standby power supply for each safety related load group consists of one DG complete with its accessories and fuel storage and transfer systems. It is capable of supplying essential loads necessary to reliably and safely shutdown and isolate the reactor. Each DG is rated at 6,201 kilowatts (kW) for continuous operation. Additional ratings are 6,635 kW for 2,000 hours, 6,821 kW for 7 days, and 7,441 kW for 30 minutes. The generator 2-hour rating is equal to the 7-day rating. Each DG is connected exclusively to a single 4160 V engineered safety features (ESF) bus for one load group. The load groups are redundant and have similar safety related equipment. Each load group is adequate to satisfy minimum engineered safety features demand caused by a LOCA and/or loss of preferred power supply. The DGs are electrically isolated from each other. Physical separation for fire and missile protection is provided between the DGs, since they are housed in separate rooms of a seismic Category I structure. Power and control cables for the DGs and associated switchgear are routed to maintain physical separation.
 
==4.0 TECHNICAL EVALUATION==
 
SR 3.8.1.10 requires verification, at least once per 18 months, of the DG capability to reject a full load without tripping on overspeed or exceeding the predetermined voltage limits. The DG full load rejection may occur because of a system fault or inadvertent breaker tripping. This Surveillance ensures proper engine generator load response under the simulated test conditions. This test simulates the loss of the total connected load that the DG experiences following a full load rejection and verifies that the DG does not trip upon loss of the load. The associated acceptance criteria provide for DG damage protection. While the DG is not expected to experience this transient during an event and continues to be available, this response ensures that the DG is not degraded for future application, including reconnection to the bus if the trip initiator can be corrected or isolated.
 
Attachment I to ET 12-0018 Page 4 of 10 The SR 3.8.1.10 maximum voltage limit is currently 4784 V; approximately 115% of the nominal grid voltage of 4160 V - a difference of 624 V. However, if the initial grid voltage is higher than nominal at the start of the load rejection test, the maximum voltage limit specified by SR 3.8.1.10 can be exceeded, even though the difference between the initial voltage and the peak voltage is less than 624 V.
SR 3.8.1.10 is normally performed once per 18 months, when the plant is shutdown for refueling. In this condition, the switchyard voltage can be higher than the nominal voltage in order to support transmission system needs. Therefore, switchyard voltage varies throughout the day, resulting in voltages that are sometimes at nominal, sometimes less than nominal, and sometimes higher than nominal at the DG electrical terminals. Increasing the SR 3.8.1.10 maximum voltage limit to 4992 V (i.e., 120% of the nominal voltage) would allow performing the associated load rejection test at any time during the plant shutdown period, even with the grid voltage higher than nominal.
WCNOC reviewed pertinent regulatory guidance and industry standards to determine the basis for the DG overvoltage limits during a full load rejection condition. The following documents were reviewed:
* Regulatory Guide (RG) 1.9, "Selection, Design, and Qualification of Diesel-Generator Units used as Onsite Electrical Power Systems at Nuclear Power Plants," Revision 1, dated November 1978,
* RG 1.9, "Selection, Design, Qualification, and Testing of Emergency Diesel Generator Units Used as Class 1E Onsite Electric Power Systems at Nuclear Power Plants,"
Revision 2, dated December 1979;
* RG 1.9, "Selection, Design, Qualification, and Testing of Emergency Diesel Generator Units Used as Class 1E Onsite Electric Power Systems at Nuclear Power Plants,"
Revision 3, dated July 1993;
* RG 1.108, "Periodic Testing of Diesel Generator Units Used as Onsite Electric Power Systems at Nuclear Power Plants," Revision 1, dated August 1977,
* Institute of Electrical and Electronic Engineers (IEEE) Standard 387-1977, "IEEE Standard Criteria for Diesel-Generator Units Applied as Standby Power Supplies for Nuclear Power Generating Stations," and
* IEEE Standard 387-1984, "IEEE Standard Criteria for Diesel-Generator Units Applied as Standby Power Supplies for Nuclear Power Generating Stations."
The original design and testing of the WCGS DGs conformed to RG 1.9, Revision 1, which endorsed IEEE Standard 387-1977 as well, and RG 1.108, Revision 1. In letter MO 12-0002 (Reference 1), WCNOC proposed to specify conformance to RG 1.9, Revision 3, which integrates the pertinent guidance previously addressed in RG 1.9, Revisions 1 and 2, and RG 1.108, Revision 1, and endorses IEEE Standard 387-1984 with respect to design, qualification, and periodic testing of DG units, subject to the supplemental design considerations specified in Section C.1 and the DG testing provisions specified in Section C.2 of RG 1.9.
 
Attachment I to ET 12-0018 Page 5 of 10 RG 1.108, Revision 1, paragraph C.2.a(4) requires demonstration of proper operation during DG load shedding, including a test of the loss of the largest single load and of complete loss of load, and verification that the voltage requirements are met and that the overspeed limits are not exceeded. IEEE Standard 387-1977, paragraph 6.4.5 states that load rejection tests shall demonstrate the capability of rejecting the maximum rated load without exceeding speeds or voltages which will cause tripping, mechanical damage, or harmful overstresses. RG 1.9, Revision 3, paragraph C.2.2.8 states that the Full Load Rejection Test is a demonstration of the DG's capability to reject a load equal to 90 to 100 percent of its continuous rating while operating at power factor between 0.8 and 0.9, and verify that the voltage requirements are met and that the DG will not trip on overspeed. IEEE Standard 387-1984, paragraph 6.3.4 states that load rejection tests shall demonstrate the capability of rejecting the short-time rated load without exceeding speeds or voltage which will cause tripping or component damage.
With no numerical overvoltage criteria specified in the guidance documents, the overvoltage limit was originally specified as 4784 V, which is 115% of a nominal bus voltage of 4160 V, based on the the Standard Technical Specifications (STS) (e.g., NUREG-0454, "Standard Technical Specifications for Westinghouse Pressurized Water Reactors") which were in effect during the initial licensing of WCGS. This value was adopted for WCGS without modification and did raise any concern until power demands on the electrical grid necessitated an increase in grid voltage for transmission. A review of the regulatory guidance documents and industry standards, indicates that the overvoltage resulting from full load rejection would not result in equipment damage which could prevent subsequent use of the affected DG. In addition, the standard industry value for peak voltage has been changed to a value of 5000 V in the improved STS (e.g., NUREG-1431, "Standard Technical Specifications - Westinghouse Plants," SR 3.8.1.10).
Based on the foregoing, WCNOC is proposing a new maximum voltage limit of 4992 V for SR 3.8.1.10, which represents a value of 120% of the nominal 4160 V.
WCNOC has evaluated the effects of the increased SR 3.8.1.10 maximum voltage limit as follows:
Generator, Cables, and Switchqear Based on the design, the generator can withstand a voltage of 9300 V from initial factory test report data. Per NEMA MG-1-1978 22.51 High-potential Tests - B. Test Voltage -
Armature Windings, the test voltage for all generators (with the exception of those described in paragraph F) shall be an alternating voltage whose effective value is 1000 V plus twice the rated voltage of the machine. The test voltage is modified for in-service generators, by a 0.67 de-rating factor, per IEEE Standard 43-1974, "IEEE Recommended Practice for Testing Insulation Resistance of Rotating Machinery," and IEEE Standard 95-1977, "IEEE Recommended Practice for Insulation Testing of Large AC Rotating Machinery." For WCGS, the original test voltage was 9320 V with follow on tests conducted at 6298 V.
It is acceptable to increase the voltage limit for the full load rejection from 4784 V (115%
of a nominal 4160 V) to 4992 V (120% of a nominal 4160 V) so that the protective relay can actuate without false alarms. The voltage increase is low enough that it does not challenge the electrical insulation of the stator, but high enough to prevent nuisance alarms.
 
Attachment I to ET 12-0018 Page 6 of 10 The generator output cables are rated for 5000 V continuous use, phase to ground. This is the expected maximum voltage in a full load reject and well below the recommended test voltages of the cables per IEEE Standard 323-1974, "IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations." The exciter feeder cables are rated at a minimum of 600 V, which provides acceptable margin over the 150 V value (i.e., 125 V *120%) that would result from a 4992 V transient with the generator being self-excited and the static exciter voltage regulator not compensating for the increased voltage.
The switchgear has a rated maximum voltage of 4760 V, a low frequency withstand voltage insulation level of 19 kilovolts (kV), and an impulse withstand voltage insulation level of 60 kV. This means that the switchgear could operate continuously at 4760 V, and withstand a transient DC Voltage of 19 kV to ground or 13.3 kV root-mean-square AC. Since the expected transient is 4992 V, this is acceptable.
Control Circuitry For the Static Exciter Voltage Regulator (SEVR) System, the power rectifier assembly is tied directly to the power current transformer, which is fed from the DG, but controlled by the logic and firing circuit. The power amplifier assembly is tied to the power potential transformer, and is also controlled by the logic and firing circuit. The logic and firing circuit is in series from the power potential transformer and then a 480/120 V 50VA transformer. Thus a voltage transient would primarily affect the logic and firing circuit.
Within the logic and firing circuit, the power supply, firing circuit input, and AC voltage error detector would see the increased voltage. The power supply would see a 120%
voltage transient from the secondary side of three transformers as 96 V rather than the expected 80 V. This additional 16 V would translate to 61.12 VDC from positive to negative sides of the rectifier bridge. With the two zener diodes and the 100 W /
100 ohm resistor in series across the circuit, the additional 13.12 V above the 48 V controlled by the diodes would be dissipated by the resistor. If the 480/120 V 50VA transformer was at full rated power before the transient, then the secondary current would be at 0.42 amperes, and conservatively assuming that current were constant during the transient, the resistor would need to dissipate 5.5 watts, which is well within its design.
The firing circuit input acts as an isolation circuit for the 3-phase pulse generator and contains overvoltage circuitry. The overvoltage output causes the pulses to phase back whenever the 6 phase rectified dc signal exceeds the pick-up point of the "overvoltage" potentiometer. The overvoltage circuitry prevents the generator from experiencing excessively high terminal voltage due to a failure in the potential transformer sensing or error detector circuitry by causing the generator terminal voltage to oscillate slightly at the overvoltage pick-up setting.
The 3-phase pulse generator card compares the phases to each other and thus a relatively uniform voltage transient across all three phases would not impact the generating of pulses.
The AC voltage error detector card provides a polarized error signal proportional to the deviation of the average 3-phase machine terminal voltage from the desired operating
 
Attachment I to ET 12-0018 Page 7 of 10 value as set by the voltage adjuster. The circuitry accepts a voltage signal derived from the machine line current that alters the error signal as the receiver current changes, and is typically used for reactive current compensation. Any voltage transient that is relatively uniform, such as from a full load reject would have a nominal net effect, and the phase angle correction would behave normally.
Summary WCNOC has concluded that the voltage transient is not beyond the design capabilities of the components, thus no degradation would be incurred from short DG output voltages of 4992 V.
In addition, the SR requirements continue to assure that the DG is not degraded for future application, including reconnection to the bus if the trip initiator can be corrected or isolated.
 
==5.0    REGULATORY EVALUATION==
 
This section addresses the standards of 10 CFR 50.92 as well as the applicable regulatory requirements and acceptance criteria.
The proposed amendment increases the voltage limit for the diesel generator (DG) full load rejection test specified by Wolf Creek Generating Station (WCGS) Technical Specification (TS) 3.8.1, "AC Sources - Operating," Surveillance Requirement (SR) 3.8.1.10.
5.1    Significant Hazards Consideration Wolf Creek Nuclear Operating Corporation (WCNOC) has evaluated whether or not a significant hazards consideration is involved with the proposed amendment by focusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," Part 50.92(c), as discussed below:
: 1.      Does the proposed amendment involve a significant increase in the probability or consequences of an accident previously evaluated?
Response: No There are no design changes associated with the proposed change. Design, material, and construction standards that were applicable prior to this amendment request will continue to be applicable.
The proposed change will not affect accident initiators or precursors nor adversely alter the design assumptions, conditions, and configuration of the facility or the manner in which the plant is operated and maintained with respect to such initiators or precursors.
The DGs' safety function is solely mitigative and is not needed unless there is a loss of offsite power.
The proposed change increases the TS SR limit on maximum voltage following a load rejection but does not physically alter safety related systems nor affect the way in which safety related systems perform their functions. The proposed change does not involve a physical change to the DGs, nor does it change the safety function of the DGs. As such, the proposed change will not alter or prevent the capability of structures, systems, and components (SSCs) to perform their intended functions for mitigating the consequences
 
Attachment I to ET 12-0018 Page 8 of 10 of an accident and meeting applicable acceptance criteria. The technical analysis performed to support this proposed amendment has demonstrated that the DGs can withstand voltages above the new proposed maximum voltage limit without a loss of protection. The proposed higher limit will continue to provide assurance that the DGs are protected, and the safety function of the DGs will be unaffected by the proposed change.
Therefore, the proposed change does not involve a significant increase the probability or consequences of an accident previously evaluated.
: 2. Does the proposed amendment create the possibility of a new or different kind of accident from any accident previously evaluated?
Response: No With respect to any new or different kind of accident, there are no proposed design changes nor or there any changes in the method by which any safety related plant SSC performs its specified safety function. The proposed change will not affect the normal method of plant operation or change any operating parameters. No new accident scenarios, transient precursors, failure mechanisms, or limiting single failures will be introduced as a result of this amendment.
The proposed amendment will not alter the design or performance of the 7300 Process Protection System, Nuclear Instrumentation System, Solid State Protection System, Balance of Plant Engineered Safety Features Actuation System, Main Steam and Feedwater Isolation System, or Load Shedder and Emergency Load Sequencers used in the plant protection systems.
The proposed increase in the TS SR limit does not affect the interaction of the DGs with any system whose failure or malfunction can initiate an accident. The change does not involve a physical modification of the plant. There are no alterations to the parameters within which the plant is normally operated. No changes are being proposed to the procedures relied upon to mitigate a design basis event. The change does not have a detrimental impact on the manner in which plant equipment operates or responds to an actuation signal.
Therefore, the proposed change will not create the possibility of a new or different kind of accident from any accident previously evaluated.
: 3. Does the proposed amendment involve a significant reduction in a margin of safety?
Response: No There will be no effect on those plant systems necessary to assure the accomplishment of protection functions associated with reactor operation or the Reactor Coolant System.
The will be no impact on the overpower limit, departure from nucleate boiling ratio (DNBR) limits, heat flux hot channel factor, nuclear enthalpy rise hot channel factor, loss of coolant accident peak cladding temperature, peak local power density, or any other limit and associated margin of safety. Required shutdown margins in the CORE OPERATING LIMITS REPORT will not be changed.
 
Attachment I to ET 12-0018 Page 9 of 10 The proposed change does not eliminate any surveillance or alter the Frequency of surveillances required by the TSs. The increase in the TS SR voltage limit will not affect the ability of the DGs to perform their safety function.
Therefore, the proposed change does not involve a significant reduction in a margin of safety.
Conclusion Based on the above evaluation, WCNOC concludes that the proposed amendment presents no significant hazards consideration under the standards set forth in 10 CFR 50.92(c) and, accordingly, a finding of "no significant hazards consideration" is justified.
5.2    Applicable Regulatory Requirements/Criteria The following regulatory requirements and guidance documents apply to the DGs:
    "  GDC 2 requires that SSCs important to safety be designed to withstand the effects of natural phenomena such as earthquakes, tornadoes, hurricanes, floods, tsunami, and seiches without the loss of the capability to perform their safety functions.
* GDC 4 requires that SSCs important to safety be designed to accommodate the effects of, and to be compatible with, the environmental conditions associated with the normal operation, maintenance, testing, and postulated accidents, including loss-of-coolant accidents. These SSCs shall be appropriately protected against dynamic effects, including the effects of missiles, pipe whipping, discharging fluids that may result from equipment failures, and from events and conditions outside the nuclear power unit.
However, dynamic effects associated with postulated pipe ruptures in nuclear power units may be excluded from the design basis when analyses reviewed and approved by the Commission demonstrate that the probability of fluid system piping rupture is extremely low under conditions consistent with the design basis for the piping.
* GDC 17 requires, in part, that nuclear power plants have onsite and offsite electric power systems to permit the functioning of SSCs that are important to safety. The onsite system is required to have sufficient independence, redundancy, and testability to perform its safety function, assuming a single failure. The offsite power system is required to be supplied by two physically independent circuits that are designed and located so as to minimize, to the extent practical, the likelihood of their simultaneous failure under operating and postulated accident and environmental conditions. In addition, this criterion requires provisions to minimize the probability of losing electric power from the remaining electric power supplies as a result of loss of power from the unit, the offsite transmission network, or the onsite power supplies.
* GDC 18 requires that electric power systems that are important to safety must be designed to permit appropriate periodic inspection and testing.
There will be no changes to the DGs such that compliance with any of the above regulatory requirements would come into question.
 
Attachment I to ET 12-0018 Page 10 of 10 Based on the considerations discussed above, 1) there is a reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, 2) such activities will be conducted in compliance with the Commission's regulations, and 3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
5.3    Precedent The NRC has approved the following similar amendments increasing the voltage limit for load rejection testing:
: 1.      Amendment No. 140 to Facility Operating License No. NPF-43 for the Fermi 2 facility, dated May 9, 2000 (ADAMS Accession No. ML003713918).
: 2.      Amendment No. 276 to Facility Operating License No. DPR-74 for Donald C. Cook Nuclear Plant, Unit 2, dated April 13, 2006 (ADAMS Accession No. ML061150354).
: 3.      Amendment No. 295 to Renewed Facility Operating License No. DPR-58 for Donald C.
Cook Nuclear Plant, Unit 1, dated September 1, 2006 (ADAMS Accession No. ML061350255).
For the precedents 1 and 3 above, the changes were requested on an emergency basis following replacement of the DG voltage regulator. WCNOC is not requesting the proposed change on an emergency basis and is not associated with the replacement of the voltage regulator. The change is proposed to accommodate grid voltage fluctuations.
: 6.      ENVIRONMENTAL CONSIDERATION WCNOC has evaluated the proposed amendment and has determined that the proposed amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amount of effluent that my be released offsite, or (iii) a significant increase in the individual or cumulative occupational radiation exposure.
Accordingly, the proposed amendment meet the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environment impact statement or environmental assessment need be prepared in connection with the proposed amendment.
 
==7.0      REFERENCES==
: 1.      WCNOC letter MO 12-0002, "Docket No. 50-482: Response to Request for Additional Information Regarding License Amendment Request to Revise Technical Specification (TS) 3.8.1, "AC Sources - Operating," dated August 16, 2012.
 
Attachment II to ET 12-0018 Page 1 of 2 ATTACHMENT II PROPOSED TECHNICAL SPECIFICATION CHANGES (MARK-UP)
 
Attachment II to ET 12-0018 AC Sources - Operating Page 2 of 2 3.8.1 SURVEILLANCE REQUIREMENTS (continued)
SURVEILLANCE                                    FREQUENCY SR 3.8.1.7 All DG starts may be preceded by an engine prelube period.
Verify each DG starts from standby condition and          184 days achieves:
: a. In < 12 seconds, voltage _>3740 V and frequency 58.8 Hz; and
: b. Steady state voltage -_3740 V and _<  4320 V, and frequency &#x17d;_58.8 Hz and < 61.2 Hz.
SR 3.8.1.8        Not Used.
SR 3.8.1.9        Not Used.
SR 3.8.1.10        Verify each DG operating at a power factor*< 0.9 and      18 months
_>0.8 does not trip and voltage is maintained < 47-84 V and frequency is maintained _<    65.4 Hz during and    _
following a load rejection of _>5580 kW and _<  6201 kW. 4992 (continued)
Wolf Creek - Unit 1                            3.8-9          Amendment No. 123, 154, 161, 163  I
 
Attachment III to ET 12-0018 Page 1 of 2 ATTACHMENT III REVISED TECHNICAL SPECIFICATION PAGES
 
AC Sources - Operating 3.8.1 SURVEILLANCE REQUIREMENTS (continued)
SURVEILLANCE                                    FREQUENCY SR 3.8.1.7            ----------------- NOTE          ------------------
All DG starts may be preceded by an engine prelube period.
Verify each DG starts from standby condition and          184 days achieves:
: a. In < 12 seconds, voltage _>3740 V and frequency
                          >_58.8 Hz; and
: b. Steady state voltage >_3740 V and < 4320 V, and frequency __58.8 Hz and < 61.2 Hz.
SR 3.8.1.8        Not Used.
SR 3.8.1.9        Not Used.
SR 3.8.1.10        Verify each DG operating at a power factor
* 0.9 and      18 months
                    > 0.8 does not trip and voltage is maintained < 4992 V and frequency is maintained < 65.4 Hz during and following a load rejection of __5580 kW and < 6201 kW.
(continued)
Wolf Creek - Unit 1                            3.8-9        Amendment No. 123, 154, 161, 163, 1}}

Latest revision as of 06:48, 10 March 2020

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