ML11277A022
| ML11277A022 | |
| Person / Time | |
|---|---|
| Site: | McGuire, Mcguire  |
| Issue date: | 09/26/2011 |
| From: | Repko R Duke Energy Carolinas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML11277A022 (26) | |
Text
DukeREGIS T. REPKO Duke Vice President 6 Energy McGuire Nuclear Station Duke Energy MGO1VP / 12700 Hagers Ferry Rd.
Huntersville, NC 28078 980-875-4111 980-875-4809 fax regis. repko@duke-energy. com September 26, 2011 10 CFR 50.90 U. S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001
Subject:
Duke Energy Carolinas, LLC (Duke Energy)
McGuire Nuclear Station, Units 1 and 2 Docket Nos. 50-369 and 50-370 Amendment to Technical Specification 3.8.3, "Diesel Fuel Oil and Starting Air"
Reference:
Licensee Event Report 369/2010-04, Revision 0, November 23, 2010 In accordance with the provisions of 10 CFR 50.90, Duke Energy is submitting a License Amendment Request (LAR) for the Renewed Facility Operating License (FOL) and Technical Specifications (TS) for McGuire Nuclear Station Units 1 and 2.
The proposed LAR seeks to adopt Westinghouse Standard Technical Specification (STS)
(NUREG-1431) 3.8.3 Condition E regarding Diesel Generator starting air receiver pressure limits. McGuire deviated from this STS condition during its conversion to STS in November of 1998. This LAR fulfills'a planned corrective action in the reference Licensee Event Report.
The enclosure provides Duke Energy's evaluation of the LAR which contains a description of the proposed TS changes, the technical analysis, the regulatory evaluation, the determination that this LAR contains No Significant Hazards Considerations, and the basis for the categorical exclusion from performing an Environmental Assessment/Impact Statement. provides existing TS pages, marked-up to show the proposed changes. provides existing TS Bases pages, marked up to show the proposed changes.
The proposed TS Bases changes are provided to you for information only. Reprinted TS pages will be provided to the NRC upon issuance of the approved amendment.
The NRC's standard 30-day implementation grace period will be sufficient to implement this LAR. There are no regulatory commitments contained in this submittal.
The McGuire Updated Final Safety Analysis Report will be updated per 10 CFR 50.71(e).
In accordance with Duke Energy internal procedures and the Quality Assurance Topical Report, the proposed amendment has been reviewed and approved by the McGuire Plant Operations Review Committee.
www.duke-energy.com (Z L
U. S. Nuclear Regulatory Commission September 26, 2011 Page 2 Pursuant to 10 CFR 50.91, a copy of this LAR has been forwarded to the appropriate North Carolina state official.
Please direct any questions you may have in this matter to P. T. Vu at (980) 875-4302.
Very truly yours, Regis T. Repko Enclosure
U. S. Nuclear Regulatory Commission September 26, 2011 Page 3 xc:
V. M. McCree Administrator, Region II U.S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, GA 30303-1257 J. Zeiler NRC Senior Resident Inspector McGuire Nuclear Station J. H. Thompson (addressee only)
NRC Project Manager U.S. Nuclear Regulatory Commission 11555 Rockville Pike Mail Stop 0-8 G9A Rockville, MD 20852-2738 W. L. Cox, IlI, Section Chief Division of Environmental Health, Radiation Protection Section North Carolina Department of Environmental and Natural Resources 1645 Mail Service Center Raleigh, NC 27699-1645
U. S. Nuclear Regulatory Commission September 26, 2011 Page 4 Regis T. Repko affirms that he is the person who subscribed his name to the foregoing statement, and that all the matters and facts set forth herein are true and correct to the best of his knowledge.
Regis T. R-epko, VicePresident, McGuire Nuclear Station Subscribed and sworn to me:
Date Notary Public My commission expires:
(Tul,/ /2O/2-
'Date
U. S. Nuclear Regulatory Commission Enclosure September 26, 2011 Page 1 of 8 ENCLOSURE EVALUATION OF PROPOSED CHANGES
Subject:
License Amendment Request to Revise Technical Specification 3.8.3 Condition D - Diesel Generator Starting Air Receiver Pressure 1.0
SUMMARY
DESCRIPTION 2.0 DETAILED DESCRIPTION
3.0 TECHNICAL EVALUATION
4.0 REGULATORY EVALUATION
4.1 Applicable Regulatory Requirements/Criteria 4.2 Significant Hazards Consideration 4.3 Conclusions
5.0 ENVIRONMENTAL CONSIDERATION
6.0 PRECEDENT
7.0 REFERENCES
ATTACHMENTS:
- 1. Technical Specification Page Markups
- 2. Technical Specification Bases Page Markups
U. S. Nuclear Regulatory Commission September 26, 2011 Enclosure Page 2 of 8 1.0
SUMMARY
DESCRIPTION Pursuant to 10 CFR 50.90, Duke Energy is requesting a license amendment request (LAR) for the McGuire Nuclear Station Units 1 and 2 Renewed Facility Operating Licenses (FOL) and Technical Specifications (TS). The proposed LAR revises the McGuire TS 3.8.3, Diesel Fuel Oil and Starting Air, to prevent a condition in which the starting air system could be operated outside the conditions allowed by TS. This LAR fulfills a planned corrective action in Licensee Event Report 369/2010-04 Revision 0 dated November 23, 2010. The proposed LAR seeks to adopt, with a minor modification, Westinghouse Standard Technical Specification (STS)
(NUREG-1 431) 3.8.3 Condition E regarding Diesel Generator (DG) Starting Air (VG) receiver pressure limits. McGuire deviated from this STS condition during its conversion to STS in November of 1998. The minor modification involves adding a Note to STS Condition E to reflect McGuire's VG system design. This design consists of two VG sub-trains for each DG, and each sub-train is capable of starting the DG engine alone, or in parallel with the other sub-train.
TS 3.8.3 Condition D currently specifies:
CONDITION REQUIRED ACTION COMPLETION TIME D.
One or more DGs with D.1 Initiate action to isolate the Immediately 1 of 2 starting air degraded starting air receiver pressures receiver.
< 210 psig.
AND D.2 Restore both starting air 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> receiver pressures to > 210 psig.
The proposed TS 3.8.3 Condition D is as follows:
D.
NOTE ---------
D.1 Restore starting air receiver 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> A single starting air pressure to > 210 psig.
receiver may be isolated without entering Condition D.
One or more DGs with starting air receiver pressure < 210 psig and
> 125 psig.
U. S. Nuclear Regulatory Commission Enclosure September 26, 2011 Page 3 of 8 2.0 DETAILED DESCRIPTION STS Condition E required that with one or more DGs with starting air receiver pressure
< [225] psig and > [125] psig, restore starting air receiver pressure to > [225] psig within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />. McGuire deviated from this STS condition during its conversion to STS in November of 1998. Instead, McGuire adopted the following as TS Condition D:
"When one or more DGs with 1 of 2 starting air receiver pressure < 210 psig, isolate the degraded air receiver immediately and restore both starting air receiver pressures to > 210 psig within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />".
This condition implies that DG operability is contingent upon both starting air receivers being > 210 psig.and if either one is < 210 psig then the system is degraded. However, there are no regulatory requirements for two starting air receivers per DG and with only one starting air receiver > 210 psig there is sufficient capacity to provide for five successive starts of the DG.
The current TS 3.8.3.Condition D was written with the goal of ensuring at least one of the two starting air receivers was maintained at a pressure > 210 psig. Unfortunately, the chosen wording restricted the ability to use an existing cross-connection line between the starting air sub-trains by creating a condition in which the starting air system was operated outside the conditions allowed by TS. This condition exists when both receivers are connected together, there are no longer two air receivers and TS 3.8.3 Condition D cannot be applied. To correct this, McGuire requests to change the words of TS 3.8.3 Condition D to match those of STS Condition E. A minor modification involves adding a Note to STS Condition E to allow one VG air receiver tank to be isolated without affecting a DG operability. McGuire's VG system design consists of two VG sub-trains for each DG, and each sub-train is capable of starting the DG engine alone, or in parallel with the other sub-train.
The proposed TS Condition D is as follows:
D.
NOTE --------------
D.1 Restore starting air receiver 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> A single starting air pressure to > 210 psig.
receiver may be isolated without entering Condition D.
One or more DGs with starting air receiver pressure < 210 psig and
> 125 psig.
The justification for the proposed change is detailed in Section 3.0.
U. S. Nuclear Regulatory Commission Enclosure September 26, 2011 Page 4 of 8
3.0 TECHNICAL EVALUATION
The McGuire onsite electrical power system consists of all sources of electrical power and their associated distribution systems in each of the two generating units. These sources are the main generator, two DGs, and the batteries.
Each unit has two redundant and independent 4160 Volt Essential Auxiliary Power Systems which normally receive power from the normal power distribution system. After verification of a loss of offsite power (LOOP) or a sustained degraded offsite power condition, the normal and alternate incoming feeder circuit breakers automatically trip. During a LOOP condition, power to each of the redundant 4160 Volt Essential Auxiliary Power Systems is provided by a completely independent DG. Each of the 4160 Volt Essential Auxiliary Power System (1E) electrical buses is totally capable of fulfilling their design function independently. There are no overlapping electrical loads shared between the 1 E buses; a loss of one DG does not increase the demand on any other DG.
McGuire Updated Final Safety Analysis Report Figure 9-143 provides a summary flow diagram of the VG system. Note that this figure will be revised to show the cross-connection line between the VG sub-trains upstream of the VG receiver tanks. The VG system provides a start capability for the DG engines by using compressed air to roll the engines until they start. In addition, it supplies control air for shutdown of the DG engines. The VG system for each DG consists of two parallel sub-trains. Each sub-train consists of an air compressor, an aftercooler, filters, a dryer, and a receiver tank. The VG receiver tank volume is approximately 100 cubic feet. There are sufficient piping connections to allow for alternate means to charge the air receivers with cool, dry compressed air, such as from portable compressed air bottles. The receiver tanks accept cooled, dry compressed air for storage until needed during an engine start. A cross-tie between the sub-trains upstream of the air receiver tanks for each DG is provided. The cross-tie provides the ability for one compressed air source to charge either or both air receivers. This is typically used during maintenance activities (e.g., a compressor is out of service).
For the McGuire engines, upon receiving a diesel start signal, all four starting air solenoid valves open. These valves remain open until the engine reaches 40% rated speed, or until 20 seconds passes and a timer secures the starting sequence. While these starting air valves, are open, both air receivers of the diesel engine are connected together through the left and right bank starting air headers on the diesel engine. Should one starting air receiver be in a reduced pressure condition, possibly completely depressurized, upon receiving a start signal, the starting air valves will open aligning the fully pressurized air receiver to divert air to the reduced pressure air receiver. To prevent this diversion of air from the fully charged air receiver to the reduced pressure air receiver, the degraded starting air receiver is isolated immediately as directed by alarm response procedures upon receipt of the low starting air pressure alarm.
DG starting air system normal alignment allows air from both receivers to enter both left and right starting air headers. When one receiver is isolated, both left and right starting air headers are supplied from the remaining receiver. With the degraded receiver isolated and the remaining receiver > 210 psig, the capacity for five starts exists and entry into Condition D is not required. Therefore, Condition D is modified by a Note that states that a single air receiver may be isolated without entering Condition D. Each DG is fully OPERABLE whenever a single starting air receiver is pressurized > 210 psig and is capable of performing its necessary and
U. S. Nuclear Regulatory Commission Enclosure September 26, 2011 Page 5 of 8 related support function. A single DG receiver pressurized to > 210 psig has sufficient air capacity for five successive DG starts; therefore, entering condition D when one receiver is isolated is not necessary.
When a DG starting air receiver is isolated, the redundant DG starting air receiver maintains DG OPERABILITY. With starting air receiver pressure < 210 psig, sufficient capacity for five successive DG starts does not exist. However, as long as the receiver pressure is > 125 psig, there is adequate capacity for at least one start, and the DG can be considered OPERABLE while the starting air receiver pressure is restored to the required limit. A period of 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> is considered sufficient to complete restoration to the required pressure prior to declaring the DG inoperable. This period is acceptable based on the remaining air start capacity, the fact that most DG starts are accomplished on the first attempt, and the low probability of an event during this brief period. Condition E is required whenever the remaining DG starting air receiver is not restored within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or cannot be restored within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.
Prior to manually isolating a degraded receiver and upon receiving a diesel start signal, part of the starting air is lost to pressurizing the degraded receiver. With either starting air receiver pressure < 210 psig and > 125 psig, Condition D applies until the degraded receiver is isolated.
Therefore, alarm response procedures ensure this period is minimized and actions are taken to isolate the degraded receiver. With the degraded starting air receiver isolated and the remaining receiver pressure > 210 psig, the capacity for five starts exists and the DG can be considered OPERABLE while the repairs necessary to restore the degraded receiver are completed.
Each VG sub-train is capable of starting the diesel engine alone, or in parallel with the other sub-train. Each receiver tank is sized to contain a sufficient volume of air for five successive DG engine starts. Empirical test data from VG system testing was used to determine the mass of air required per start during multiple starts from a single air receiver. These results were then analyzed by adjusting for the most limiting system conditions. It was determined that under the most limiting initial conditions, 210 psig receiver pressure, room temperature at 125 degrees F (The DG room temperature can vary from 55 degrees F to 125 degrees F without declaring the associated DG inoperable), and only one VG air receiver available, the McGuire DG could start at least five times. This results in available margin in the proposed VG receiver pressure limits.
Empirical test data indicated the DG will start at the lowest pressure of 108 psig. The +/- 8 psig total loop uncertainty ensures there is adequate air at the 125 psig setpoint for one successful start.
The proposed adoption of STS 3.8.3 Condition E regarding VG receiver pressure limits will result in McGuire being consistent with the industry and eliminate the entry into the Action Statement anytime a compressor and/or a receiver tank is taken out of service for maintenance.
The proposed changes do not have any adverse impact on the ability of the DGs to start to mitigate a loss of non-emergency AC power accident analyzed in UFSAR Section 15.2.6.
4.0 REGULATORY EVALUATION
4.1 Applicable Regulatory Requirements/Criteria:
As required by 10 CFR 50, Appendix A, General Design Criteria (GDC) 17, an onsite electric power system shall be provided to permit functioning of structures, systems and components
U. S. Nuclear Regulatory Commission Enclosure September 26, 2011 Page 6 of 8 important to safety. The onsite electric power supplies, including the batteries, and the onsite electric distribution system, shall have sufficient independence, redundancy, and testability to perform their safety functions assuming a single failure.
McGuire Safety Evaluation Report dated March 1978, Section 9.5.2 discussed VG system as follows: "Each diesel generator unit has an independent starting air system with sufficient storage to provide four consecutive starts. Sufficient redundancy is provided, and the redundant systems are so arranged that a malfunction or failure in one system does not impair the ability of the other system to start the diesel engine."
The proposed changes to TS 3.8.3 Condition D are consistent with NUREG-1431 and conservative in nature. The proposed changes clarify that the VG system is redundant at the train level, not the sub-train level. The proposed changes have no adverse impact on the DGs ability to fulfill their design basis function as required by GDC-17.
4.2 Significant Hazards Consideration:
The proposed amendment seeks to adopt Standard Technical Specification (STS) 3.8.3 Condition E regarding Diesel Generator (DG) starting air receiver pressure limits.
Duke Energy has concluded that operation of McGuire Units 1 & 2, in accordance with the proposed changes to the Technical Specifications does not involve a significant hazards consideration. Duke Energy's conclusion is based on its evaluation, in accordance with 10 CFR 50.91(a)(1), of the three standards set forth in 10 CFR 50.92(c) as discussed below:
A. Does the proposed amendment involve a significant increase in the probability or consequences of an accident previously evaluated?
Response: No.
Implementation of the proposed amendment does not significantly increase the probability or the consequences of an accident previously evaluated. The DGs and their associated emergency buses function as accident mitigators. The proposed changes do not involve a change in the operational limits or the design of the electrical power systems (particularly the emergency power systems) or change the function or operation of plant equipment or affect the response of that equipment when called upon to operate:
The proposed changes to TS 3.8.3 Condition D are consistent with STS 3.8.3 Condition E, and they still ensure the DGs' ability to fulfill their safety related function.
Thus, based on the above, the proposed changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.
B. Does the proposed amendment create the possibility of a new or different kind of accident from any accident previously evaluated?
Response: No.
U. S. Nuclear Regulatory Commission Enclosure September 26, 2011 Page 7 of 8 The proposed changes do not involve a change in the operational limits or the design capabilities of the emergency electrical power systems. The proposed changes do not change the function or operation of plant equipment or introduce any new failure mechanisms. The technical evaluation that supports this License Amendment Request included a review of the DG starting air system capability to which these changes are bounded. The proposed changes do not introduce any new or different types of failure mechanisms; plant equipment will continue to respond as designed and analyzed.
C. Does the proposed amendment involve a significant reduction in the margin of safety?
Response: No.
Margin of safety is related to the confidence in the ability of the fission product barriers to perform their design functions during and following an accident situation. These barriers include the fuel cladding, the reactor coolant system, and the containment system. The performance of the fuel cladding, the reactor coolant system and the containment system will not be adversely impacted by the proposed changes since the ability of the DGs to mitigate an analyzed accident has not been adversely impacted by the proposed changes.
Thus, it is concluded that the proposed changes do not involve a significant reduction in the margin of safety.
4.3
==
Conclusions:==
The proposed changes do not involve a change in the operational limits or the design capabilities of the emergency electrical power systems. The proposed changes do not change the function or operation of plant equipment or introduce any new failure mechanisms. The ability to successfully start the DGs does not change.
5.0 ENVIRONMENTAL CONSIDERATION
The proposed changes do not involve a significant hazards consideration, a significant change in the types of or significant increase in the amounts of any effluents that may be released offsite, or a significant increase in individual or cumulative occupational radiation exposure.
Therefore, the proposed changes meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), an environmental assessment of the proposed changes is not required.
6.0 PRECEDENT None.
7.0 REFERENCES
1 McGuire Technical Specification 3.8.3, Amendment Nos. 184/166.
2 McGuire Technical Specification Bases 3.8.3, Revision 115.
U. S. Nuclear Regulatory Commission Enclosure September 26, 2011 Page 8 of 8 3
Westinghouse Standard Technical Specifications (NUREG-1431), Rev. 3.0, 3.8.3 -
Diesel Fuel Oil, Lube Oil, and Starting Air, March 31, 2004.
4 McGuire UFSAR 9.5.6, Diesel Generator Starting Air System, October 10, 2009.
5 McGuire UFSAR 8.3.1, AC Power Systems Generic Description, October 10, 2009.
6 McGuire UFSAR 8.3.1.1.4, 4160 Volt Essential Auxiliary Power system, October 10, 2009.
7 McGuire UFSAR Figure 9-143, Summary Flow Diagram of Diesel Generator Engine Starting Air System (VG), October 10, 2009.
8 McGuire UFSAR 15.2.6, Loss of Non-Emergency AC Power to the Station Auxiliaries, October 10, 2009.
9 McGuire Safety Evaluation Report Section 9.5.2, Diesel Generator Starting Air System, March 1978.
10 McGuire License Amendments 184/166, Full Conversion to Standard Technical Specifications (NUREG-1431, Revision 1), September 30, 1998.
11 Licensee Event Report 369/2010-04, Revision 0, Improper Technical Specification Application when Diesel Generator Starting Air Receivers Cross-Tied, November 23, 2010.
ATTACHMENT 1 Marked-up TS Pages
Diesel Fuel Oil and Starting Air 3.8.3 3.8 ELECTRICAL POWER SYSTEMS 3.8.3 Diesel Fuel Oil and Starting Air LCO 3.8.3 APPLICABILITY:
The stored diesel fuel oil and starting air subsystem shall be within limits for each required diesel generator (DG).
When associated DG is required to be OPERABLE.
ACTIONS
NOTE-Separate Condition entry is allowed for each DG.
CONDITION REQUIRED ACTION COMPLETION TIME A.
One or more DGs with A.1 Restore fuel oil level to 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> fuel oil inventory within limits.
< 39,500 gal and
> 31,600 gal.
B.
One or more DGs with B. 1 Restore fuel oil total 7 days stored fuel oil total particulates within limit.
particulates not within limit.
C.
One or more DGs with C. 1 Restore stored fuel oil 30 days new fuel oil properties properties to within limits.
not within limits.
(continued)
McGuire Units 1 and 2 3.8.3-1 Amendment Nos. 184/166
Diesel Fuel Oil and Starting Air 3.8.3 ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME D.
On r ore DGs with*
of 2 starting air
,-receiver pre res
< 210
- g.
7W 7
D. 1 Initiate act o isolate the degr d starting air D.2 Restore bot tarting air receive ressures to Ž 210 p.
/I-I t
Immediately 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> 2e ZZ E.
Required Action and associated Completion Time not met.
OR One or more DGs diesel fuel oil or starting air
-subsystem not within limits for reasons other than Condition A, B, C, or D.
E.1 Declare associated DG inoperable.
Immediately McGuire Units 1 and 2 3.8.3-2 Amendment Nos. [lj4%ý
Insert 1:
D. ---------- NOTE--------
A single starting air receiver may be isolated without entering Condition D.
One or more DGs with starting air receiver pressure < 210 psig and
> 125 psig.
D. 1 Restore starting air receiver pressure to > 210 psig.
48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />
Ke d--144-a-
4ktý--
f"I'me-Diesel Fuel Oil and Starting Air 3.8.3 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.8.3.1 Verify the fuel oil storage system contains > 39,500 gal of In accordance with fuel for each DG.
the Surveillance Frequency Control Program SR 3.8.3.2 Verify fuel oil properties of new and stored fuel oil are In accordance with tested in accordance with, and maintained within the the Diesel Fuel Oil limits of, the Diesel Fuel Oil Testing Program.
Testing Program SR 3.8.3.3 Verify each DG air start receiver pressure is _ 210 psig.
In accordance with the Surveillance Frequency Control Program SR 3.8.3.4 Check for and remove accumulated water from the fuel In accordance with oil storage tank.
the Surveillance Frequency Control Program McGuire Units 1 and 2 3.8.3-3 Amendment No. 261/241
ATTACHMENT 2 Marked-up TS Bases Pages
Diesel Fuel Oil and Starting Air B 3.8.3 B 3.8 ELECTRICAL POWER SYSTEMS B 3.8.3 Diesel Fuel Oil and Starting, Air BASES BACKGROUND Each diesel generator (DG) is provided with a storage tank having a fuel oil capacity sufficient to operate that diesel for a period of 5 days while the DG is supplying maximum post loss of coolant accident load demand discussed in the UFSAR, Section 8.3.1.1.7 (Ref. 1). The maximum load demand is calculated using the assumption that a minimum of any two DGs is available. This onsite fuel oil capacity is sufficient to operate the DGs for longer than the time to replenish the onsite supply from outside sources.
Fuel oil is transferred from storage tank to day tank by either of two transfer pumps associated with each storage tank. Redundancy of pumps and piping precludes the failure of one pump, or the rupture of any pipe, valve or tank to result in the loss of more than one DG. All outside tanks, pumps, and piping are located underground.
For proper operation of the standby DGs, it is necessary to ensure the proper quality of the fuel oil. Regulatory Guide 1.137 (Ref. 2) addresses the recommended fuel oil practices as supplemented by ANSI N195 (Ref. 3). The fuel oil properties governed by these SRs are the water and sediment content, the kinematic viscosity, specific gravity (or API gravity),
and impurity level.
Each DG has an air start system with adequate capacity for five successive star*9 on the DG without recharging the air start receiver(s).
APPLICABLE SAFETY ANALYSES The initial conditions of Design Basis Accident (DBA) and transient analyses in the UFSAR, Chapter 6 (Ref. 4), and in the UFSAR, Chapter 15 (Ref. 5), assume Engineered Safety Feature (ESF) systems are OPERABLE. The DGs are designed to provide sufficient capacity, capability, redundancy, and reliability to ensure the availability of necessary power to ESF systems so that fuel, Reactor Coolant System and containment design limits are not exceeded. These limits are discussed in more detail in the Bases for Section 3.2, Power Distribution Limits; Section 3.4, Reactor Coolant System (RCS); and Section 3.6, Containment Systems.
Since diesel fuel oil and the air start subsystem support the operation of the standby AC power sources, they satisfy Criterion 3 of 10 CFR 50.36 (Rev. 6).
McGuire Units 1 and 2 B 3.8.3-1 Revision No-12ý
Diesel Fuel Oil and Starting Air B 3.8.3 BASES LCO Stored diesel fuel oil is required to have sufficient supply for 5 days of full load operation. It is also required to meet specific standards for quality.
DG day tank fuel requirements, as well as transfer capability from the storage tank to the day tank, are addressed in LCO 3.8.1, "AC Sources-Operating," and LCO 3.8.2, "AC Sources-Shutdown." This requirement, in conjunction with an ability to obtain replacement supplies within 4 days, supports the availability of DGs required to shut down the reactor and to maintain it in a safe condition for, an anticipated operational occurrence (AOO) or a postulated DBA with loss of offsite power.
The starting air system is Eguired to have a minimum capacity for 5 successive DG startQe t without recharging the air start receivers.
APPLICABILITY The AC sources (LCO 3.8.1 and LCO 3.8.2) are required to ensure the availability of the required power to shut down the reactor and maintain it in a safe shutdown condition after an AOO or a postulated DBA. Since stored diesel fuel oil and the starting air subsystem support LCO 3.8.1 and LCO 3.8.2, stored diesel fuel oil and starting air are required to be within limits when the associated DG is required to be OPERABLE.
ACTIONS The ACTIONS Table is modified by a Note indicating that separate Condition entry is allowed for each DG. This is acceptable, since the Required Actions for each Condition provide appropriate compensatory actions for each inoperable DG subsystem. Complying with the Required Actions for one inoperable DG subsystem may allow for continued operation, and subsequent inoperable DG subsystem(s) are governed by separate Condition entry and application of associated Required Actions.
A.1 In this Condition, the 5 day fuel oil supply for a DG is not available.
However, the Pondition is restricted to fuel oil level reductions that maintain at least a 4 day supply. These circumstances may be caused by events, such as full load operation required after an inadvertent start while at minimum required level, or feed and bleed operations, which may be necessitated by increasing particulate levels or any number of other oil quality degradations. This restriction allows sufficient time for obtaining the requisite replacement volume and performing the analyses required prior to addition of fuel oil to the tank. A period of 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> is considered sufficient to complete restoration of the required level prior to declaring the DG inoperable. This period is acceptable based on the remaining capacity (> 4 days), the fact that procedures will be initiated to obtain replenishment, and the low probability of an event during this brief period.
McGuire Units 1 and 2 B 3.8.3-2 Revision No."
Diesel Fuel Oil and Starting Air B 3.8.3 BASES ACTIONS (continued)
B. 1 This Condition is entered as a result of a failure to meet the acceptance criterion of SR 3.8.3.2. Normally, trending of particulate levels allows sufficient time to correct high particulate levels prior to reaching the limit of acceptability. Poor sample procedures (bottom sampling),
contaminated sampling equipment, and errors in laboratory analysis can produce failures that do not follow a trend. Since the presence of particulates does not mean failure of the fuel oil to burn properly in the diesel engine, and particulate concentration is unlikely to change significantly between Surveillance Frequency intervals, and proper engine performance has been recently demonstrated (within 31 days), it is prudent to allow a brief period prior to declaring the associated DG inoperable. The 7 day Completion Time allows for further evaluation, resampling and re-analysis of the DG fuel oil.
C.1 With the new fuel oil properties defined in the Bases for SR 3.8.3.2 not within the required limits, a period of 30 days is allowed for restoring the stored fuel oil properties. This period provides sufficient time to test the stored fuel oil to determine that the new fuel oil, when mixed with previously stored fuel oil, remains acceptable, or to restore the stored fuel oil properties. This restoration may involve feed and bleed procedures, filtering, or combinations of these procedures. Even if a DG start and load was required during this time interval and the fuel oil properties were outside limits, there is a high likelihood that the DG would still be capable of performing its intended function.
D.I1 DG starting aa tem normal alignment all s air from both receivers to enter bo i-eft and right starting air he rs. Therefore, with one receiv isolod, both left and right starti air headers will be supplied fr e
rzfnaining receiver. With t egraded receiver isolated an e remaining receiver Ž_ 210 psig, t apacity for 5 starts exists. In interim prior to manually isolati e egraded receiver, part of starting air would Ye lost to pres izing the degraded receiver.
erefore, this period mT>
be minim' and action to isolate the d ded receiver shall b ' iated immediately.
With the degraded ing air receiver isolate d the remaining re ver pressure Ž 21 sig, the capacity for 5 sta exists, and the DG be consider PERABLE while the de ed air receiver press e is 1;7 M ;"c ýL-
,ý 1A McGuire Units 1 and 2 B 3.8.3-3 Revision No. un
Diesel Fuel Oil and Starting Air B 3.8.3 BASES ACTIONS (continued) restor to the requ d limit. A peri f 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> is copidered sufficie to mplete res ation to the r ired pressure pri,9 o declaring the operable.
is period is eptable based one remaining air rt capacity e fact that t DG starts are ac mplished on the st
- atter, and the lo rrobability of an ev during this pen E.1 With a Required Action and associated Completion Time not met, or one or more DG's fuel oil or starting air subsystem not within limits for reasons other than addressed by Conditions A through D, the associated DG may be incapable of performing its intended function and must be immediately declared inoperable.
SURVEILLANCE REQUIREMENTS SR 3.8.3.1 This SR provides verification that there is an adequate inventory of fuel oil in the storage tanks to support each DG's operation for 5 days at full load.
The 4 day period is sufficient time to place the unit in a safe shutdown condition and to bring in replenishment fuel from an offsite location.
The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.
SR 3.8.3.2 The tests listed below are a means of determining whether new fuel oil is of the appropriate grade and has not been contaminated with substances that would have an immediate, detrimental impact on diesel engine combustion. If results from these tests are within acceptable limits, the fuel oil may be added to the storage tanks without concern for contaminating the entire volume of fuel oil in the storage tanks. These tests are to be conducted prior to adding the new fuel to the storage tank(s). The tests, limits, and applicable ASTM Standards are as follows:
- a.
Sample the new fuel oil in accordance with ASTM D4057 (Ref. 7);
- b.
Verify in accordance with the tests specified in ASTM D975 that the sample has a kinematic viscosity at 400C of > 1.9 centistokes and
< 4.1 centistokes, and a flash point of > 125 0F; and McGuire Units 1 and 2 B 3.8.3-4 Revision N -0
Insert 2:
DG starting air system normal alignment allows air from both receivers to enter both left and right starting air headers. When one receiver is isolated, both left and right starting air headers are supplied from the remaining receiver. With the degraded receiver isolated and the remaining receiver > 210 psig, the capacity for five starts exists and entry into Condition D is not required. Therefore, Condition D is modified by a Note that states that a single air receiver may be isolated without entering Condition D. Each DG is fully OPERABLE whenever a single starting air receiver is pressurized > 210 psig and is capable of performing its necessary and related support function. A single DG receiver pressurized to > 210 psig has sufficient air capacity for five successive DG starts; therefore, entering condition D when one receiver is isolated is not necessary.
When a DG starting air receiver is isolated, the redundant DG starting air receiver maintains DG OPERABILITY. With starting air receiver pressure < 210 psig, sufficient capacity for five successive DG starts does not exist. However, as long as the receiver pressure is > 125 psig, there is adequate capacity for at least one start, and the DG can be considered OPERABLE while the starting air receiver pressure is restored to the required limit. A period of 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> is considered sufficient to complete restoration to the required pressure prior to declaring the DG inoperable. This period is acceptable based on the remaining air start capacity, the fact that most DG starts are accomplished on the first attempt, and the low probability of an event during this brief period. Condition E is required whenever the remaining DG starting air receiver is not restored within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or cannot be restored within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.
Prior to manually isolating a degraded receiver and upon receiving a diesel start signal, part of the starting air is lost to pressurizing the degraded receiver. With either starting air receiver pressure < 210 psig and > 125 psig, Condition D applies until the degraded receiver is isolated.
Therefore, alarm response procedures ensure this period is minimized and actions are taken to isolate the degraded receiver. With the degraded starting air receiver isolated and the remaining receiver pressure > 210 psig, the capacity for five starts exists and the DG can be considered OPERABLE while the repairs necessary to restore the degraded receiver are completed.
/if ArAe4--
Diesel Fuel Oil and Starting Air B 3.8.3 BASES SURVEILLANCE REQUIREMENTS (continued)
- c.
Verify that the new fuel oil has a clear and bright appearance with proper color when tested in accordance with ASTM D4176 (Ref. 7) or a water and sediment content within limits when tested in accordance with ASTM D2709 (Ref. 7); and
- d.
Verify that the new fuel oil has an absolute specific gravity at 60 /
60°F of > 0.83 and < 0.89 when tested in accordance with ASTM D1298 or an API gravity at 60°F of> 270 and < 390 when tested in accordance with ASTM D287 (Ref.7).
Failure to meet any of the above limits, except for clear and bright, is cause for rejecting the fuel oil, but does not represent a failure to meet the LCO concern since the fuel oil is not added to the storage tanks. If the fuel oil fails on clear and bright, it may be accepted if it passes water and sediment. The specifications for water and sediment recognize that a small amount of water and sediment is acceptable. Thus, this test may be used after a clear and bright test to provide a more quantitative result.
Within 31 days following the initial new fuel oil sample, the fuel oil is analyzed to establish that the other properties specified in Table 1 of ASTM D975 (Ref. 7) are met for new fuel oil when tested in accordance with ASTM D975 (Ref. 7), except that the analysis for sulfur may be performed in accordance with ASTM D5453 (Ref. 7), D3120 (Ref. 7) or ASTM D2622 (Ref. 7). The 31 day period is acceptable because the fuel oil properties of interest, even if they were not within stated limits, would not have an immediate effect on DG operation. This Surveillance ensures the availability of high quality fuel oil for the DGs.
Fuel oil degradation during long term storage shows up as an increase in particulate, due mostly to oxidation. The presence of particulate does not mean the fuel oil will not burn properly in a diesel engine. The particulate can cause fouling of filters and fuel oil injection equipment, however, which can cause engine failure.
Particulate concentrations should be determined based on ASTM D6217 (Ref. 7). This test method is used for assessing the mass quantity of particulates in middle distillate fuels, which includes 2-D diesel fuel. This method involves a gravimetric determination of total particulate concentration in the fuel oil and has a limit of 10 mg/l. For those designs in which the total stored fuel oil volume is contained in two or more interconnected tanks, each tank must be considered and tested separately.
The Frequency of this test takes into consideration fuel oil degradation trends that indicate that particulate concentration is unlikely to change significantly between Frequency intervals.
McGuire Units 1 and 2 B 3.8.3-5 Revision No.7 j
MJ CtA*~~A
- Diesel Fuel Oil and Starting Air B 3.8.3 BASES SURVEILLANCE REQUIREMENTS (continued)
SR 3.8.3.3 This Surveillance ensures that, without the aid of the refill compressor, sufficient air start capacity for each DG is available. The system design requirements provide for a minimum of five engine start cycles without recharging. A start cycle is defined as the period of time required to reach 95% speed from standby prelubed condition. The pressure specified in this SR is intended to reflect a conservative value at which a single fast start and five total starts can be accomplished.
The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.
SR 3.8.3.4 Microbiological fouling is a major cause of fuel oil degradation. There are numerous bacteria that can grow in fuel oil and cause fouling, but all must have a water environment in order to survive. Removal of water from the fuel storage tanks eliminates the necessary environment for bacterial survival. This is the most effective means of controlling microbiological fouling. In addition, it eliminates the potential for water entrainment in the fuel oil during DG operation. Water may come from any of several sources, including condensation, ground water, rain water, and contaminated fuel oil, and from breakdown of the fuel oil by bacteria.
Frequent checking for and removal of accumulated water minimizes fouling and provides data regarding the watertight integrity of the fuel oil system. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program. This SR is for preventive maintenance. The presence of water does not necessarily represent failure of this SR, provided the accumulated water is removed during performance of the Surveillance.
McGuire Units 1 and 2 B 3.8.3-6 Revision No.]-l
I'.tJ W a,/4' Diesel Fuel Oil and Starting Air B 3.8.3 BASES REFERENCES 1.
2.
3.
4.
5.
6.
7.
8.
9.
UFSAR, Section 8.3.1.1.7.
ANSI N195-1976, Appendix B.
UFSAR, Chapter 6.
UFSAR, Chapter 15.
10 CFR 50.36, Technical Specifications, (c)(2)(ii).
ASTM Standards: D4057; D975; D1298; D4176; D2709; D6217; D2622; D287; D5453; and D3120.
UFSAR, Section 18.2.4, Chemistry Control Program.
McGuire License Renewal Commitments MCS-1274.00-00-0016, Section 4.6, Chemistry Control Program.
McGuire Units 1 and 2
[] 3.8.3-7 Revision Nolý!]