RNP-RA/17-0041, Transmittal of Technical Specifications Bases Revisions

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Transmittal of Technical Specifications Bases Revisions
ML17160A260
Person / Time
Site: Robinson Duke Energy icon.png
Issue date: 05/23/2017
From: Sherman C
Duke Energy Corp
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
RNP-RA/17-0041
Download: ML17160A260 (24)


Text

Charles E. Sherman H. B. Robinson Steam Electric Plant Unit 2 Director - Nuc Org Effectiveness ef_-,DUKE Duke Energy

~ ENERGY 3581 West Entrance Road Hartsville, SC 29550 0: 843 857 1609 F: 843 8571319 Chuck.Sherma11@duke-e11ergy.com TS 5.5.14 Serial: RNP-RA/17-0041 MAY 2 3 2017 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555 H.i3. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 DOCKET NO. 50-261/RENEWED LICENSE NO. DPR-23 Transmittal of Technical Specifications Bases Revisions Ladies and Gentlemen:

In accordance with Technical Specifications 5.5.14.d, Duke Energy is transmitting revisions to the H. B. Robinson Steam Electric Plant, Unit No. 2 (HBRSEP2), Technical Specifications Bases. The attachment to this letter provides Technical Specifications Bases pages for Revisions 67 through

69. .

This letter contains no new Regulatory Commitments.

If you have any questions concerning this matter, please contact Mr. Tony Pilo, Manager- Nuclear Regulatory Affairs at (843) 857-1409.

Sincerely /1J//.

. r__y)ah-k Charles E. Sherman Director - Nuc Org Effective ,.....,,,.,,., __

CES/jmw Attachment c: NRG Resident Inspector, HBRSEP NRG Regional Administrator, Region II Mr. Dennis Galvin, NRG Project Manager, NRR

United States Nuclear Regulatory Commission Attachment to Serial: RNP-RA/17-0041

. 23 Pages (including cover page)

H. 8. Robinson Steam Electric Plant, Unit No. 2 Technical Specifications Bases Pages For Revisions 67 Through 69

TECHNICAL SPECIFICATIONS BASES EFFECTIVE PAGES i 0 i.1 69 i.2 66 i.3 31 i.4 57 i.5 55 i.6 55 i.7 64 i.8 58 i.9 69 i.10 63 i.11 68 i.12 67 i.13 61 i.14 32 ii 0 iii 32 iv 0 B 4.0-1 0 B 2:0-2 0 B 2.0-3 3 B 2.0-4 3 B 2.0-5 3, B 2.0-6 31 B 2.0-7 0 B 2.0~8 31 B 2.0"'.9 31 B 3.0-1 52 8 3.0-2 28 B 3.0-3 28 B 3.0-4 28 B 3.0-5 28 B 3.0-6 28 B 3.0-:7 28 B 3.0-8 28 B 3.0-9 28 B 3.0-10 52 B 3.0-11 52 B 3.0-12 52 B 3;0-13 52 B 3.0-14 69 B 3.0-15 69 B 3.0-16 52 B .3.0-11 52 B 3.0-18 52.

83.1-1 0 B 3.1-2 0 B 3.1-3 0 B 3.1-4 31 B 3 . 1-5 0 B 3~ 1-6 31 B 3.1-7 0 B 3.1-8 0, B 3.1-9 0 HBRSEP, Unit No. 2 - i.1 -

  • Rev. 69

TECHNICAL SPECIFICATIONS BASES EFFECTIVE PAGES Page Rev.

B 3.5-6 0 B 3.5-7 0 B 3.5-8 lo B 3.5-9 0 B 3.S-10 0 B 3.5-11 .0 B 3.5-12 0 B 3.5-13 0 B 3.5-14 0 B 3.5-15 0 B 3.5-16 0 B 3.5-,17 33 B 3.5-18 0 B 3.5-19 0 B 3.5-20. 0 B 3.5~~1 43 B 3.5-22 43 B 3.5-23 28 B 3.5-24 0 B 3.5-25 0 B 3.5-26 0 B 3.5-27 0 B 3.5-28 46 B 3.5-29 0 B 3.5-30 0 B 3.6-1 69 B 3.6-2 69 B 3.6-3 69 B 3.S-4 69 B 3.6-5 69 B 3.p-6 0 B 3.6-7 69 B 3.6-8 0 83.6-9 0 B 3.6-10 0 B 3.6-11 69 B 3.6-12 69 B 3.6-13 37 B 3.6-14 37 8 3.6-15 37 B 3.6-16 44 B 3.6-17 37 B 3.6-1a 37 B 3.6-19 37 B 3.6-20 37 B 3.S-21 37 B 3.6-22 37 B 3.6-23 37 B 3.6-24 37 B 3.6-25 37 B 3.6-26 34 HBRSEP, Unit No. 2 - i.9 - Rev. 69

TECHNICAL SPECIFICATIONS BASES EFFECTIVE PAGES Page B 3.7-24 0 B 3.7-25 28 B 3.7-25a 28 B 3.7:-26 0 B 3~7-27 0 B 3.7-28 19 8:3.7-29 19 B 3.7-30 0 B 3.7-31 19 B 3.7-32 0 B 3.7-33 23 B 3*.7-34. 0 B 3.7-35 0 B 3.7-36 0 B 3.7-37 15 B 3.7-38 68.

B 3.7-39 14 B 3.7-'40 0 B 3.7-41 0 B 3.7-42 15 B 3.7-43 68 B 3.7-44 0 B 3.7-45 0 B 3.7-46 0 B 3.7-47 0 B 3.7-48 0 B 3.7-49 15 83.7-50 68 B 3.7-50a 20 B 3.7-51 20 e 3.7-52 51 B 3.7-53. 59 B 3.7-54 39 B 3.7-55 39 B 3.7-56 39 B 3.7-57 48 B 3.7-58, B 3.7-58a 48 B 3.7-59 18 B 3.7-60 22 B 3.7-61. 22 B 3.7-62 0 8 3.7-63 22 B 3.7-64 22 B 3.7-65 0 B 3.7-66 39 B 3.7-67 22 B 3.7-68 0 B 3.7-69 22 B 3.7-70 25 B 3.7-71 25 B 3.7-72 25 B 3.7-73 25 HBRSEP, Unit No. 2 - i.11 - Rev. 68

TECHNICAL SPECIFICATIONS BASES EFFECTIVE PAGES Page Rev.

B 3.7-74 25 83.7-75. 25 B 3.7-76 25 B 3.7-77 26 B 3.7-78 26 B 3.7-79 0 B 3.7-80 26 B 3.8-1 42 B 3.8-2 0

  • B 3.8-3 0 B 3.8-4 0 B 3.8-5 28 B 3.8-6 28 B 3.8-7 0 B 3.8-8 0 B 3.8-9 67 B 3.8-9a 67 B 3.8-10 67 B 3.8-11 67 B 3.8-12 67 B 3.8-13 0 B 3.8-14 0 B 3.8-15 0 B 3.8-16 0 B 3.8-17 0 B 3.8-18 0 B 3.8-19 30 B 3.8-20 30 B 3.8-21 0 B 3.8-22 0 B 3.8-23 0 B 3.8-24 0 B 3.8-25 0 B 3.8:-26 0 B 3.8-27 0 B 3.8-28 0 B 3.8-29 16 B 3.8-30 16 B 3.8-31 16 B 3.8-32 0 B 3.8-33 0 B 3:8-34 0 B 3.8-35 49 B 3.8-36 65 B 3.8-37 0 B 3.8-38 41 B 3.8-39 13 B 3.8-40 0 B 3.8-41 0 B 3.8-42 0 B 3.8-43 . 29 B 3.8-44 29 HBRSEP, Unit No: 2 -i.12- Rev. 67

SR Applicability B 3.0 BASES SR 3.0.1 Surveillances, including Surveillances invoked by Required (continued)

Actions, do not have to be performed on inoperable equipment because the ACTIONS define the remedial measures that apply. Surveillances have to be met and performed in accordance with SR 3.0.2, prior to returning equipment to OPERABLE status.

Upon completion of maintenance, appropriate post maintenance testing is required to declare equipment OPERABLE. This includes ensuring applicable Surveillances are not failed and their most recent performance is in accordance with SR 3.0.2. Post maintenance testing may not be possible in the current MODE or other specified conditions in the Applicability due to the necessary unit parameters not having been established. In these situations, the equipment may be considered OPERABLE provided testing has been satisfactorily completed to the extent possible and the equipment is not otherwise believed to be incapable of performing its function. This will allow operation to proceed to a MODE or other specified condition where other necessary post maintenance tests can be completed.

SR 3.0.2 SR 3.0.2 establishes the requirements for meeting the specified Frequency for Surveillances and any Required Action with a Completion Time that equires the periodic performance of the Required Action on a "once per ... " interval.

SR 3.0.2 permits a 25% extension of the interval specified in the Frequency. This extension facilitates Surveillance scheduling and considers plant operating conditions that may not be suitable for conducting the Surveillance (e.g., transient conditions or other ongoing Surveillance or maintenance activities).

The 25% extension does not significantly degrade the reliability that results from performing the Surveillance at its specified Frequency. This is pased on the recognition that the most probable result of any particular Surveillance being performed is the verification of conformance with the SRs. The exceptions to SR 3.0.2 are those Surveillances for which the 25% extension of the interval specified in the Frequency does not apply.

These exceptions are stated in the individual Specifications.

(continued)

HBRSEP Unit No. 2 B 3.0-14 Revision No. 69

SR Applicability B 3.0 BASES SR 3.0.2 The requirements of regulations take precedence over the TS.

(continued) An example of where SR 3.0.2 does not apply is in the Containment Leakage Rate Testing Program. This program establishes testing requirements and Frequencies in accordance with the requirements of regulations.

The TS cannot in and of themselves extend a test interval specified in the regulations.

As stated in SR 3.0.2, the 25% extension also does not apply to the initial portion of a periodic Completion Time that requires performance on a "once per ... " basis. The 25% extension applies to each performance after the initial performance. The initial performance of the Required Action, whether it is a particular Surveillance or some other remedial action, is considered a single action with a single Completion Time. One reason for not allowing the 25% extension to this Completion Time is that such an action usually verifies that no loss of function has occurred by checking the status of redundant or diverse components or accomplishes the function of the inoperable equipment in an alternative manner.

The provisions of SR 3.0.2 are not intended to be used repeatedly merely as an operational convenience to extend Surveillance intervals (other than those consistent with refueling intervals) or periodic Completion Time intervals beyond those specified.

SR 3.0.3 SR 3.0.3 establishes the flexibility to defer declaring affected equipment inoperable or an affected variable outside the specified limits when a Surveillance has not been completed within the specified Frequency. A delay period of up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or up to the limit of the specified Frequency, whichever is greater, applies from the point in time that it is discovered that the Surveillance has not been performed in accordance with SR 3.0.2, and not at the time that the specified Frequency was not met.

This delay period provides adequate time to complete Surveillances that have been missed. This delay period permits the completion of a Surveillance before complying with Required Actions or other remedial measures that might-preclude completion of the Surveillance.

The basis for this delay period includes consideration of unit conditions, adequate planning, availability of personnel, (continued)

HBRSEP Unit No. 2 B 3.0-15 Revision No. 69

Containment B 3.6.1 B 3.6 CONTAINMENT SYSTEMS B 3.6.1 Containment BASES BACKGROUND The containment consists of the concrete reactor building, its steel liner, and the penetrations through. this structure. The structure is designed to contain radioactive material that may be released from the reactor core following a design basis loss of coolant accident (LOCA). Additionally, this structure provides shielding from the fission products .that may be present in the containment atmosphere following accident conditions.

The containment is a reinforced concrete structure with a cylindrical wall, a flat foundation mat, and a shallow dome roof. The inside surface of the containment is lined with a s~ainless steel liner to ensure a high degree of leak tightness during operating and accident conditions.

The cylinder wall is prestressed with a post tensioning system in the vertical direction.

The concrete reactor building is required for structural integrity of the containment under Design Basis Accident (OBA) conditions. The steel liner and its penetrations establish the leakage limiting boundary of the containment. Maintaining the containment OPERABLE limits the leakage of fission product radioactivity from the containment to the environment.

SR 3.6.1.1 leakage rate requirements comply with 10 CFR 50, Appendix J, Option B (Ref. 1), as modified by approved exemptions.

The isolation devices for the penetrations in the containment boundary are a part of the containment leak tight barrier. To maintain this leak tight barrier:

a. All penetrations required to be closed during accident conditions are either:
1. capable of being closed by an OPERABLE automatic containment isolation system, or
2. . closed by manual valves, blind flanges, or de-activated automatic valves secured in their closed positions, except as provided in LCO 3.6.3, "Containment Isolation Valves";

(continued)

HBRSEP Unit No. 2 B 3.6-1 Revision No. 69

Containment B 3.6.1 BASES BACKGROUND b. The air lock is OPERABLE, except as provided in (continued) LCO 3.6.2, "Containment Air Lock";

c. The equipment hatch.is closed and sealed; and
d. The Isolation Valve Seal Water (IVSW) sytem is OPERABLE, except as provided in LCO 3.6.8.

APPLICABLE The safety design basis for the conta.inment is that the SAFETY ANALYSES containment must withstand the pressures and temperatures of the limiting OBA without exceeding the design leakage rate.

The DBAs that result in a challenge to containment OPERABILITY from high pressures and temperatures are a LOCA and a steam line break (Ref. 2). In addition, release of significant fission product radioactivity within containment can occur from a LOCA. In the LOCA analyses, it is assumed. that the containment is OPERABLE such that, for the LOCA, the release to the environment is controlled by the rate of containment leakage. The containment has an allowable leakage rate of 0.1 % of containment air weight per day (Ref. 2). This leakage rate, used to evaluate offsite doses resulting from accidents, is defined in 10 CFR 50, Appendix J, Option B (Ref. 1), as La: the maximum allowable containment leakage rate at the calculated peak containment internal pressure (Pa) resulting from the design basis LOCA. At HBRSEP, Unit 2, Pa is specified as the containment design pressure of 42 psig. The allowable leakage rate represented by La forms the basis for the acceptance criteria imposed on all containment leakage rate testing. La is assumed to be

=

0.1 % per day in the safety analysis at Pa 42 psig (Ref. 2).

Satisfactory leakage rate test results are a requirement for the establishment of containment OPERABILITY.

The containment satisfies Criterion 3 of the NRC Policy Statement.

(continued)

HBRSEP Unit No. 2 B 3.6-2 Revision No. 69

Containment B 3.6.1 BASES (continued)

LCO Containment OPERABILITY is maintained by limiting leakage to ::;; 1.0 La.

except prior to the first startup after performing a required Containment Leakage Rate Testing Program leakage test. At this time, the applicable leakage limits must be met.

Compliance with this LCO will ensure a containment configuration, including the* equipment hatch, that is structurally sound and that will limit leakage to those leakage rates assumed in the safety analysis.

Individual leakage rates specified for the containment air lock are not specifically part of the acceptance criteria of 10 CFR 50, Appendix J.

Therefore, leakage rates exceeding these individual limits only result in the containment being inoperable when the leakage results in exceeding the overall acceptanGe criteria of 1.0 La.

APPLICABILITY In MODES 1, 2, 3, and 4, a LOCA could cause a release of radioactive material into containment. In MODES 5 and 6, the probability and consequences of these events are reduced due to the pressure and temperature limitations of these MODES. Therefore, containment is not required to be OPERABLE in MODE 5 to prevent leakage of radioactive material from containment. The requirements for containment during MODE 6 are addressed in LCO 3.9.3, "Containment Penetrations."

ACTIONS In the event containment is inoperable, containment must be restored to OPERABLE status within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. The 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Completion Time provides a period of time to correct the problem commensurate with the importance of maintaining containment OPERABLE during MODES 1, 2, 3, and 4. This time period also ensures that the probability of an accident (requiring containment OPERABILITY) occurring during periods when containment is inoperable is minimal.

(continued)

HBRSEP Unit No. 2 B 3.6-3 Revision No. 69

Containment B 3.6.1 BASES ACTIONS B.1 and B.2 (continued)

If containment cannot be restored to OPERABLE status within the required Completion Time, the plant must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant must be brought to at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and to MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly mpnner and without challenging plant systems.

SURVEILLANCE SR 3.6.1.1 REQUIREMENTS Maintaining the containment OPERABLE requires compliance .with the leakage rate test requirements of the Containment Leakage Rate testing Program. Air lock leakage is not acceptable if its contribution to overall Type B, and C leakage causes overall Type B and C leakage to exceed limits. As left leakage prior to the first startup after performing a required Containment Leakage Rate testing Program leakage test is required to be, s0.60 La for the Type B and Type C tests, ands 0. 75 La for Type A tests. At all other times betWeen required leakage rate tests, the acceptance criteria is based on an overall leakage limit of s 1.0 La. At s 1.0 La the offsite dose.consequences are bounded by the assumptions of the safety analysis. SR Frequencies are as required by the Containment Leakage Rate testing Program. These periodic testing requirements verify that the containment leakage rate does not exceed the leakage rate assumed in the safety analysis.

Reviewer's Note: NEI 94-01 includes acceptance criteria for as-left and as-found Type A leakage rates and combined Type B and C leakaae rates. which mav be reflected in the Bases.

SR 3.6.1.2 This SR ensures that the structural integrity of the containment will be maintained in accordance with the provisions of the Containment Tendon Surveillance Program.

(continued)

HBRSEP Unit No. 2 B 3.6-4 Revision No. 69

Containment B 3.6.1 BASES REFERENCES 1. 10 CFR 50, Appendix J, Option B.

2. UFSAR, Section 6.2.

HBRSEP Unit No. 2 B 3.6-5 Revision No. 69

Containment Air Lock B 3.6.2 BASES SAFETY ANALYSES leakage. The containment has an allowable leakage rate of 0.1% of (continued) containment air weight per day .at 42 psig (Ref. 2).

The containment air lock satisfies Criterion 3 of the NRC Policy Statement.

LCO The containment air lock forms part of the containment pressure boundary. As part of containment, the air lock safety function is related to control of the containment leakage rate resulting from a OBA. Thus, the air lock's structural integrity and leak tightness are essential to the successful mitigation of such an event.

The air lock is required to be OPERABLE. For the air lock to be considered OPERABLE, the air lock interlock mechanism must be OPERABLE, the air lock must be in compliance with the Type B air lock leakage test, and both air lock doors must be OPERABLE. The interlock allows only one air lock door of an air lock to be opened at one time. This provision ensures that a gross breach of containment does not exist when containment is required to be OPERABLE. Closure of a single door in the air lock is sufficient to provide a leak tight barrier following postulated events. Nevertheless, both doors are kept closed when the air lock is not being used for normal entry into or exit from containment.

APPLICABILITY In MODES 1, 2, 3, and 4, a OBA could cause a release of radioactive material to containment. In MODES 5 and 6, the probability and consequences of these events are reduced due to the pressure and temperature limitations of these MODES. Therefore, the containment air locks are not required in MODE 5 to prevent leakage of radioactive material from containment. The requirements for the containment air locks during MODE 6 .are addressed in LCO 3.9.3, "Containment Penetrations."

(continued) .

HBRSEP Unit No. 2 B 3.6-7 Revision No.69

Containment Air Lock B 3.6.2 BASES ACTIONS C.1, C.-2, and C.3 (continued) inoperable air lock to OPERABLE status, assuming that at least one door is maintained closed in the air lock.

D.1 and D.2 If the inoperable containment air lock cannot be restored to OPERABLE status within the required Completion Time, the plant must be brought to a MODE in which the LCO does not apply.* To achieve this status, the plant must be brought to at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and to MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the. required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

SURVEILLANCE SR 3.6.2.1 REQUIREMENTS Maintaining the containment air lock OPERABLE requires compliance with the leakage rate test requirements of the Containment Leakage Rate Testing Program. This SR reflects the leakage rate testing requirements with regard to air lock leakage (Type B leakage tests). The periodic testing requirements verify that the air lock leakage does not exceed the.

allowed fraction of the qverall containment leakage rate. The Frequency is required by the Containment Leakage Rate Testing Program.

The SR has been modified by two Notes. Note 1 states that an inoperable air lock door does not invalidate the previous successful performance of the overall air lock leakage test. This is considered reasonable since either air lock door is capable of providing a fission product barrier in the event of a OBA. Note 2 has been added to this SR requiring the results to be evaluated against the acceptance criteria which is applicable to SR.3.6.1.1. This en~ures that air lock leakage is properly

  • accounted for in determining the combined Type B and C containment leakage rate.

(continued)

HBRSEP Unit No. 2 B 3.6-11 Revision No. 69

Containment Air Lock B 3.6.2 BASES SURVEILLANCE SR 3.6.2.2 REQUIREMENTS (continued) The air lock interlock is designed to prevent simultaneous opening of both doors in a single air lock. Since both the inner and outer doors of an air lock are designed to withstand the maximum expected post accident containment pressure, closure of either door will support containment OPERABILITY. Thus, the door interlock feature supports containment OPERABILITY while the air lock is being used for personnel transit in and out of the containment. Periodic testing of this interlock demonstrates that the interlock will function as designed and that simultaneous opening of the inner and outer doors will.not inadv~rtently occur. Due to the purely mechanical nature of this interlock, and given that the interlock mechanism is not normally challenged when the containment air lock door is used for entry and exit (procedures require strict adherence to single door opening), this test is only required to be performed every 24 months. The 24 month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage, and the potential for loss of containment OPE;RABILITY if the surveillance were performed with the reactor at power. The 24 month Frequency for the interlock is justified based on generic operating experience. The 24 month Frequency is based on engineering judgment and is considered adequate given that the interlock is not challenged during the use of the interlock.

REFERENCES 1.. 10 CFR 50, Appendix J, qption B.

2. UFSAR, Paragraph 6.9.2.

HBRSEP Unit No. 2 B 3.6-12 Revision No. 69

CCW System B 3.7.6 BASES LCO b. The associated system piping, valves, surge tank, and (continued) instrumentation and controls required to perform the safety related function are OPERABLE.

The isolation of CCW from other components or systems. not required for safety may render those components or systems inoperable but does not affect the OPERABILITY of the CCW System.

APPLICABILITY In MODES 1, 2, 3, and 4, the CCW System is a normally operating system, which must be prepared to perform its post accident safety functions, primarily RCS heat removal, which is achieved by cooling the RHR heat exchanger.

Although the LCO for the CCW System is not applicable in MODES 5 and 6, the capability of the CCW System to perform its necessary related support functions may be required

. for OPERABILITY of supported systems.

ACTIONS Required Action A.1 is modified by a Note indicating that thEl applicable Conditions and Required Actions of LCO 3.4.6, "RCS Loops- MODE 4,"

be entered if an inoperable CCW train results in an inoperable RHR loop.

This is an exception to LCO 3.0.6 and ensures the proper actions are taken. for these components.

If one required CCW train is inoperable, action must be taken to restore OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. In this Condition, the remaining OPERABLE CCW train is adequate to perform the heat removal function.

The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Completion Time is reasonable, based on the redundant capabilities afforded by the OPERABLE train, and the low probability of a OBA occurring during this period.

B.1 and B.2 If the required CCW train cannot be restored to OPERABLE status within the associated Completion Time, the unit must be placed in a MODE in which the LCO does not apply. To achieve this status, the unit must be placed in at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in MODE 5 withiri 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.

The (continued)

HBRSEP Unit No. 2 B 3.7-38 Revision No. 68

sws B 3.7.7 BASES LCO c. The associated piping, valves, and permanent protective (continued) enclosures (e. g, north header enclosure grating), valves, and instrumentation and controls required to perform the safety related function are OPERABLE.

The SWS Turbine Building loop isolation valves are considered OPERABLE when each header isolation valve and the isolation valve powered from the automatic bus transfer switch are OPERABLE.

APPLICABILITY In MODES 1, 2, 3, and 4, th_e SWS is a normally operating system that is required to support the OPERABILITY of the equipment serviced by the SWS and required to be OPERABLE in these MODES.

Although the LCO for the SWS is not applicable in MODES 5 and 6, the capability of the SWS to perform its necessary related support functions may be required for OPERABILITY of supported systems.

ACTIONS If one SWS train is inoperable, action must be taken to restore OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. In this Condition, the remaining OPERABLE SWS train is adequate to perform the heat removal function.

However, the overall reliability is reduced because a single failure in the OPERABLE SWS train could result in loss of SWS function. Required Action A.1 is modified a Note. The Note indicates that the applicable Conditions and Required Actions of LCO 3.8.1, "AC Sources - Operating," should be entered if an inoperable SWS train results in an inoperable emergency diesel generator. This is an

. exception to LCO 3.0.6 and ensures the proper actions are taken for these components. The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Completion Time is based on the redundant capabilities afforded by the OPERABLE train, and the low probability of a OBA occurring during this time period.

B.1 and B.2 If one SWS Turbine Building loop isolation valve is inoperable, the valve must be closed and deactivated within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. In the closed and deactivated condition, the remaining OPERABLE loop isolation valves can perform the (continued)

HBRSEP Unit No. 2 B 3.7-43 Revision No. 68

UHS B 3.7.8 BASES APPLICABLE The UHS satisfies Criterion 3 of the NRC Policy Statement.

SAFETY ANALYSES (continued)

LCO The UHS is required to be OPERABLE and is considered OPERABLE if it contains a sufficient volume of water at or below the maximum temperature that would allow the SWS to operate for at least 22 days following the design basis LOCA without the loss of NPSH, and without exceeding the maximum design temperature of the equipment served by the SWS. To meet this condition, the UHS temperature should not exceed 97°F and the level should not fall below 218 ft MSL during normal unit operation.

APPLICABILITY In MODES 1, 2, 3, and 4, the UHS is required to support the OPERABILITY of the equipment serviced by the UHS and required to be OPERABLE in these MODES.

Although the LCO for the UHS is not applicable in MODES 5 and 6, the capability of the UHS to perform its necessary related support functions may be required for OPERABILITY of supported systems.

ACTIONS A.1 and A.2 With the SW temperature> 97°F buts 99°F, the required cooling capacity of the SW System must be verified by evaluating the existing operational condition of the systems and components served by the SW System and verifying that each is capable of performing its safety related function. The required cooling capacity must also be re-verified once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. In addition, the SW temperature must be verified s 99°F once per hour. The temperature verification ensures the SW temperature remains below the maximum water temperature allowed for the safety related components to perform their safety function.

  • (continued)

HBRSEP Unit No. 2 B 3.7-50 Revision No. 68

AC Sources - Operating B 3.8.1 BASES ACTIONS B.3.1. B.3.2.1. and B.3.2.2 (continued) satisfied. If the cause of the initial inoperable DG cannot be confirmed not to exist on the remaining DG(s); performance of SR 3.8.1.2 suffices to provide assurance of continued OPERABILITY of that DG.

If it is verified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> that the OPERABLE DG is not inoperable due to common cause failure, SR 3:8.1.2 need not be performed within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. However, it is still necessary to verify the OPERABILITY of the OPERABLE DG within 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br />. Testing the OPERABLE DG more than once during the 7 day Completion Time is not required.

A NOTE has been added to take exception to perform REQUIRED ACTION B.3.2.2 and associated COMPLETION TIME for a DG intentionally removed from service solely for the reasons of performing pre-planned maintenance or SURVEILLANCE testing because no identified DG failure has occurred and the likelihood of the OPERABLE DG having an undetected failure is low. This exception is acceptable since the cause of the inoperable DG is known and is not related to correcting a DG failure mechanism (i.e., corrective maintenance) causing the DG to be inoperable when entering CONDITION B.

If a DG failure mechanism is identified at any time during preventative maintenance, corrective maintenance or during testing, REQUIRED ACTION B.3.1 or B.3.2 must be reentered for the OPERABLE DG. If the COMPLETION TIME commencing at the time the LCO was initially not met has expired, then the COMPLETION TIME commences from the time of the discovery of any failure mechanism that is identified during maintenance or testing of the inoperable DG. This allows an exception to the normal "time zero" for beginning a new COMPLETION TIME "clock." In this instance, the COMPLETION TIME "time zero" is specified as commencing at the time the failure mechanism is identified; instead of at the time the associated CONDITION was entered. REQUIRED ACTION B.3.1 or B.3.2, performance of SR 3.8.1.2 for the OPERABLE DG, need not be performed if it has been successfully performed within the previous 24-hours, or if it is currently operating. Performance of SR 3.8.1.2 within the previous 24-hours meets the intent of REQUIRED ACTION B.3.1 or B.3.2 by providing reasonable assurance that the OPERABLE DG will perform its associated safety function.

(continued)

HBRSEP Unit No. 2 B3.8-9 Revision No. 67

AC Sources - Operating B 3.8.1 BASES ACTIONS B.3~ 1, B.3.2.1, and B.3.2.2 (continued)

In the event the inoperable DG is restored to OPERABLE status prior to completing either B.3.1 or B.3.2, the plant corrective action program will continue to evaluate the common cause possibility. This continued evaluation, however, is no longer under the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> constraint imposed while in Condition B.

According to Generic Letter 84-15 (Ref. 6), 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is reasonable to confirm that the OPERABLE DG(s) is not affected by the same problem as the inoperable DG.

Operation may continue in Condition B for a period that should not exceed 7 days.

In Condition B, the remaining OPERABLE DG and offsite circuit are adequate to supply electrical power to the onsite Distribution System. The 7 day Completion Time takes into account the capacity and capability of the remaining AC sources, a reasonable time for repairs, and the low probability of a OBA occurring during this period.

The second Completion Time for Required Action B.4 establishes a limit on the maximum time allowed for any combination of required AC power sources to be inoperable during any single contiguous occurrence offailing to meet he LCO. If Condition B is entered while, for instance, an offsite circuit is inoperable and that circuit is subsequently restored OPERABLE, the LCO may already have been not met for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This could lead to a total of 8 days, since initial failure to meet the LCO, to restore the DG. At this time, an offsite circuit could again become inoperable, the DG restored OPERABLE, and an additional 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> (for a total of 9 days) allowed prior to complete restoration of the LCO. The 8 day Completion Time provides a limit on time allowed in a specified condition after discovery of failure to meet the LCO. This limit is considered reasonable for situations in which Conditions A and B are entered concurrently. The "AND" connector between the 7 day and 8 day Completion Times means that both Completion Times apply simultaneously, and the more restrictive Completion Time must be met.

As in Required Action B.2, the Completion Time allows for an exception to the normal "time zero" for beginning the allowed time "clock." This will result in establishing the "time zero" at the time that the LCO was initially not met, instead of at the time Condition B was entered.

(continued)

HBRSEP Unit No. 2 B 3.8-9a Revision No. 67

AC Sources - Operating B 3.8.1 BASES ACTIONS C.1 and C.2 (continued)

If the inoperable AC electric power sources cannot be restored to OPERABLE status within the required Completion Time, the unit must be brought to a MODE in which the LCO does not apply. To achieve this status, the unit must.be broughUo at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and to MODE 5 within 36 ho,urs. The allowed Completion Times are reasonable, based on operating experience, to reach the required unit conditions from full power conditions in an orderly manner and without challenging plant systems .

Condition D corresponds to a level of degradation in which all redundancy in the AC electrical power supplies has been lost. At this severely degraded level, any further losses in the AC electrical power system will cause a loss

. of.function. Therefore,. no additional time is justified for continued operation. The unit is required by LCO 3.0.3 to commence a controlled shutdown.

Condition is modified by a Note which permits delaying entry into the Condition for no longer than 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to permit the testing required by SR 3.R1.2 for the OPERABLE DG since this testing renders the DG inoperable.

(continued)

HBRSEP Unit No. 2 B 3.8-10 Revision No. 67

AC Sources - Operating B 3.8.1 BASES SURVEILLANCE The AC sources are designed to permit inspection and REQU,REMENTS testing of all important areas and features, especially ,those that have a standby function, in accordance with HBRSEP Design Criteria (Ref. 1).

Periodic component tests are supplemented by extensive functional tests during refueling outages (under simulated accident conditions). The SRs for demonstrating the OPERABILITY of the DGs are consistent with the recommendations of Regulatory Guide 1.137 (Ref. 6), as addressed in the UFSAR.

Where the SRs discussed herein specify voltage and frequency tolerances, the following is applicable. The minimum steady state output voltage of 467 V is 97% of the nominal 480 V output voltage. It allows for voltage drops to motors and other equipment down through the 120 V level where minimum operating voltage is also usually specified as 90% of name plate rating. The specified maximum steady state output voltage of 493 V is within the maximum operating voltage specified for the motors supplied by the 480 V subsystem. It ensures that for a lightly loaded distribution system, the voltage at the terminals of motors is no more than the maximum rated operating voltages. The specified minimum and maximum frequencies of the DG are 58.8 Hz and 61.2 Hz, respectively. These values are equal to +/- 2% of th.e 60 Hz nominal frequency and are consistent with the recommendations given in Regulatory Guide 1.9 (Ref. 7).

SR 3.8.1.1 This SR ensures proper circuit continuity for the offsite AC electrical power supply to the onsite distribution network and availability of offsite AC electrical power. The breaker alignment verifies that each breaker is in its correct position to ensure that distribution buses and loads are connected to their preferred power source. The 7 day Frequency is adequate since breaker position is not likely to change without the operator being aware of it and because its status is displayed in the control room.

(continued)

HBRSEP Unit No. 2 B 3.8-11 Revision No. 67

AC Sources - Operating B 3.8.1 BASES SURVEILLANCE SR 3.8.1.2 and SR 3.8.1.7 REQUIREMENTS (continued) These SRs help to ensure the avaHability of the standby electrical power supply to mitigate DBAs and transients and to maintain the unit in a safe shutdown* condition.

To minimize the wear on moving parts that do not get lubricated when the

  • engine is not running, these SRs are modified by a Note (Note 2 for SR 3.8.1.2) to indicate that all DG starts for these Surveillances may be preceded by an engine prelube period and followed by a warmup period prior to loading. *
  • For the purposes of SR 3.8.1.2 and SR 3.8.1. 7 testing, the DGs are started from standby conditions. Standby conditions for a DG mean that the diesel engine coolant anq oil are being continuously circulated and temperature is

~!3ing. maihtained cons.istent with manufacturer recommendations.

  • In order,to reduce stress and wear on diesel engines, the manufacturer recommends a modified start in which the starting speed of DGs is limited, warmup is limited tq this lower speed, and the DGs are gradually
  • accelerated to synchronous speed prior to loading. These start procedures are the intent of Note 3, which is only applicable when such modified start procedures are recommended by the manufacturer.

SR 3.8.1. 7 requires that, at a 184 day Frequency, the DG starts from

. standby co11ditiohs and achieves required voltage and frequency within 10 seconds; The minimum voltage and frequency stated in* the SR are those necessary .to ensure the DG can accept OBA loading while maintaining acceptable voltage and frequency levels. Stable operation at

'the nominal voitage and frequency values is also essential to establishing

    • DG OPERABILITY;* but a time constraint is not imposed. This is because a typical DG Vt(ill experience a period of voltage and frequency oscillations
  • prior to reaching steady state operation if these oscillations* are, not damped out by load application. This period may extend beyond the 10 second acceptance criteria and could be a cause for failing the SR. In lieu of a time constraint in the SR, HBRSEP Unit No. 2 will monitor and trend the actual (continued)

HBRSEP Unit No. 2 B 3.8-12 Revision No. 67