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#REDIRECT [[U-603067, Application for Amend to License NPF-65,revising Acceptance Criteria for Meeting ready-to-load Requirement Denoted by TS SR 3.8.1.17 for Division 3 DG]]
| number = ML20237E415
| issue date = 08/24/1998
| title = Application for Amend to License NPF-65,revising Acceptance Criteria for Meeting ready-to-load Requirement Denoted by TS SR 3.8.1.17 for Division 3 DG
| author name = Macfarland W
| author affiliation = ILLINOIS POWER CO.
| addressee name =
| addressee affiliation = NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
| docket = 05000461
| license number =
| contact person =
| document report number = LS-98-010, LS-98-10, U-603067, NUDOCS 9808310266
| package number = ML20237E417
| document type = OPERATING LICENSES-APPLIATION TO AMEND-RENEW EXISTING, TEXT-LICENSE APPLICATIONS & PERMITS
| page count = 9
| project =
| stage = Meeting
}}
 
=Text=
{{#Wiki_filter:_ _ _                                                                  _
Chnton Power Stabon P.O. Box 678 G'
Crinton. IL 61727 Tel 217 935-5623 Fax 217 935-4632                    i e or ce res n and Chief Nuclear Officer ILLINSIS P6WER                                                                  VIE'                                u An Illinova Company August 24,1998                      j l
i Docket No. 50-461                                                      10CFR50.90 10CFR50.59 L                                      Document Control Desk Nuclear Regulatory Commission Washington, D.C. 20555
 
==Subject:==
Clinton Power Station Proposed Amendment of                                                    )
Facility Operatina License No. NPF-62 (LS-98-010.)                                            ]
I l                                   
 
==Dear Madam or Sir:==
 
Pursuant to 10 CFR 50.59 and 10 CFR 50.90, Illinois Power (IP) hereby requests amendment of Facility Operating License NPF-62 for the Clinton Power
                                      - Station (CPS). Specifically, IP requests prompt NRC review and approval of a
!                                      proposed change to the CPS Technical Specification (TS) Bases and Updated Safety Analysis Report (USAR), for which it has been determined that an unreviewed safety question exists. The proposed change revises the acceptance criteria for meeting the
                                      " ready-to-load" requirement denoted by TS Surveillance Requirement (SR) 3.8.1.17 for                        i the Division 3 Diesel Generator (DG). The proposed change also adds a discussion of                          j this acceptance criterion to the USAR to clarify the intent of the requirement.
l 4
During the CPS conversion to the Improved Technical Specifications (ITS), the initial TS wording for the associated surveillance demonstrating the Division 3 DG test                      l mode override was revised from " standby operation" to " ready-to-load." The ITS Bases for the revised wording specified the " ready-to-load" acceptance criteria as an automatic feature. This wording revision to the TS was not identified as a technical change. Yet, this issue presents a literal compliance issue with the TS regarding the
                                      " ready-to-load" feature of the Division 3 DG since manual operator action is required to reset the governor following the receipt of an Emergency Core Cooling System signal                      fj
                                      . during the test mode. On June 26,1998, plant personnel determined that SR 3.8.1.17                        8 was not adequately satisfied by the associated surveillance procedure. CPS Licensee                    j Event Report (LER) 98-023 regarding the failure to satisfy SR 3.8.1.17 was issued identifying this concern. As such, the Division 3 DG is currently inoperable due to this            g g gl determination and will remain so until approval of this license amendment request.                  p 9808310266 990824 PDR      ADOCK 05000461 P                          PDR
[                                                                        ,
Ll___..__ 1 _ _  . _ _ _ _ _ _ _ _
 
lA                                                                                                                                                                                                U-603067 Page 2
* The CPS TS limiting condition for operation (LCO) pertaining to the ECCS for the current plant conditions (3.5.2 ECCS-Shutdown) requires two ECCS injection / spray subsystems to be operable. Since entering an outage for either Division 1 or Division 2 will automatically render two of the ECCS subsystems inoperable, it is highly desirable to                                                                                                      .i l                          be able to declare the Division 3 DG operable because it supports the high pressure core l
spray system (HPCS) which is one of the five ECCS subsystems. Without approval of this                                                                                                            j license amendment CPS can only meet the applicable TS LCO with the minimum number                                                                                                                  I of operable ECCS subsystems during a Division 1 or Division 2 outage. Although this is technically acceptable, it does not provide the most desirable level of risk reduction, particularly considering that if a determination ofinoperability is made regarding one of the two remaining ECCS subsystems it will force the operators to enter the associated TS                                                                                                          j LCO action statements. Based on the above, IP respectfully requests prompt NRC review                                                                                                          -l and approval of this application for amendment.                                                                                                                                                    l 1
I An affidavit supporting the facts set forth in this letter and its attachments is
{
provided as Attachment 1. Attachment 2 provides the background, a description of the                                                                                                              l proposed changes to the TS Bases and USAR, an evaluation of the specific issue, and an                                                                                                            j evaluation for no significant hazards consideration. Attachment 3 provides proposed                                                                                                                I marked-up pages of the TS Bases. Attachment 4 provides marked-up pages of the CPS                                                                                                                j USAR to reflect the required changes.                                                                                                                                                            ,
The proposed request was evaluated against the criteria of 10CFR51.22 for
;                          environmental considerations. The proposed change does not significantly increase                                                                                                                ,
individual or cumulative occupational radiation exposures, does not significantly change the types or significantly increase the amount of effluents that may be released off-site and, as discussed in Attachment 2, does not involve a significant hazards consideration. Based on the foregoing, it has been concluded that the proposed Technical Specification change meets the criteria given in 10CFR51.22(c)(9) for categorical exclusion from the requirement for an Environmental Impact Statement.
Sincerely yours,                                      l l
J. Aluf.
k Walter G.MacFarlan ,IV
!                                                                                                                                                                      Senior Vice President and Chief Nuclear Officer JFK/krk l                          Attachment                                                                                                                                                                                        i cc:                  Acting Regional Administrator, Region III, USNRC NRC Clinton Licensing Project Manager NRC Resident Oflice, V-690 Illinois Department ofNuclear Safety l_
L_              ______- ____ _- - - ----
 
      +,
Attachment I to U403067 Page1of1 George A. Hunger, Jr., being first duly sworn, deposes and says: That he is Manager -
Clinton Power Station; that this application for amendment of Facility Operating License
              'NPF-62 has been prepared under his supervision and direction; that he knows the contents thereof; and that to the best of his knowledge and belief said letter and the facts contained therein are true and correct.
Date: This  24      day of August 1998.
Signed:                    ,    Gua(.A .
                                                                  ' Geoge A. Huiiger, Jr.d        *'
STATE OF ILLINOIS                      (  SSJ        .gygg, gag,.            ,
(      ;    GWRE.RImeW3                >
                //4dbd          COUNTY                (      : NFIRS.8MIEoFMa10ll
: Myenesmeonentestoneseg Subscribed and sworn to before me this    2          day of August 1998.
l?/[s/                  CM Y (Notary Pu6 tic) /
 
S.                                                                                              Attachment 2 to U-603067 LS-98-010 Page 1 of 6
 
===Background===
i As documented in Licensee Event Report (LER) 98-023, a review of the closing documentation for LER 96-012 raised questions regarding whether Technical Specification (TS) Surveillance Requirement (SR) 3.8.1.17 was being met for the Division 3 emergency diesel generator (DG). SR 3.8.1.17 requires verification that, with the emergency diesel generator operating in the test mode and connected to its bus, an actual or simulated emergency core cooling system (ECCS) signal overrides the test mode by i
returning the DG to " ready-to-load" operation and automatically energizing the emergency loads from offsite power.
In accordance with the TS Bases for SR 3.8.1.17, demonstration of the test mode overide      {
ensures that the DG availability under accident conditions is not compromised as a result    j of testing. The Bases specifier that the DG must be automatically returned to a " ready-to-load" operation. The " ready-to-load" operation is defined as the DG running at rated speed and voltage with the DG output breaker open.
The design of the Division 3 DG includes a mechanical governor and always operates in a droop mode (the droop setting is set to 0 for operating when the DG is the single source of power for the Divison 3 bus). The droop mode of operation is used when the DG is operating in parallel with another source. The droop mode permits the load to be shared between the two power sources. For the Division 3 DG this configuration is necessary for      !
DG testing and is consistent with current design. Upon receipt of an ECCS initiation signal, the operator manually resets the governor, including the droop control. By
                  . comparison, the Division 1 and 2 DGs utilize electronic governces that operate in either et isochronous or droop mode. The isochronous mode of operation is used when the DG is the single source of power for the electrical bus it is supplying. Upon receipt of an ECCS initiation signal, the electronic governor automatically switches to the isochronous mode.
In the test mode, the engine governor speed droop controlis typically set to 50 to help assure that frequency is maintained within limits during performance of the DG tests.
                    '"nce the droop control setting is not automatically overridden or reset to 0 while in the test mode, manual operator action is necessary to reset the governor, including droop control setting, during the performance of SR 3.8.1.17.
With the droop control setting at 50, the generator operating frequency is reduced by L
about 3% to approximately 58.2 hertz. The nominal generator frequency required to i                    supply the connected loads during a LOCA is 60 hertz. At a droop control setting of 0, the generator operating frequency is 60 hertz. If manual action to reset the droop control
                  - setting were not performed during SR 3.8.1.17, the Division 3 DG would not provide the frequency required for proper operation of the connected loads. With the Division 3 DG dedicated to supplying power to the high pressure core spray (HPCS) pump motor and the loads that support operation of the associated pump, the reduced frequency of 58.2 hertz (with the droop control set at 50 and no operator action to increase speed) would cause
                    'the HPCS motor and pump to operate at a slower speed. This would reduce the flow rate from the HPCS pump to less than the Technical Specification required flow rate.
o
: l.    . .
N                                                                                        Attachment 2 to U-603067 LS-98-010 Page 2 of 6 l
Since the Division 3 DG will not provide the frequency required for proper operation of the high pressure core spray (HPCS) pump without operator action to adjust the governor while in the test mode, the DG cannot be considered " ready-to-load" as required to be demonstrated by SR 3.8.1.17. Therefore, SR 3.8.1.17 cannot be considered properly satisfied.
The proposed change revises the acceptance criteria for meeting the " ready-to-load" requiremer.t denoted by SR 3.8.1.17 for the Division 3 DG. The proposed change also adds a disct ssion of this acceptance criterion to the USAR to clarify the intent of the ~
l            requiremec , CPS has identified this issue as an unreviewed safety question since (1) the l            TS " ready. to-load" acceptance criteria denoted in the Bases is different from the Division .
3 DG design, and (2) the acceptance criteria of manually resetting the governor is not specifically documented in the licensing basis or in the NRCs Safety Evaluation Report (SER) from previous reviews of the CPS design.
i            Proposed Channes to the CPS TS Bases To reflect the revision of the CPS design, the changes described below and indicated on th: attached marked-up pages from the CPS TS Bases (per Attachment 3) are proposed:
o    SR 3.8.1.17 Bases (page B 3.8-27):
Added the phrase:
                  " Additionally, for the Division 3 DG, operator action is required to reset the governor to re-establish ready-to-load operation and ensure frequency limits are met."
Proposed Channes to the CPS USAR To reflect the revision of the CPS design, the changes described below and indicated on the attached marked-up pages from the CPS USAR (per Attachment 4) are proposed:
I            e    USAR Section 8.3.1.1.2.1 (page 8.3-25):
Added the paragraph:
                  "The HPCS diesel generator is designed with a mechanical governor that always operates in the droop mode. In accordance with the Technical Specifications, manual
                  . operator action is required during testing in the test mode to ensure resetting of the governor. This ensures the required generator frequency following receipt of an ECCS signal while in the test mode."
I-
 
(                  -
pY      '
Attachment 2 to U-603067 l                                                                                          LS-98-010 Page 3 of 6 Evaluath.3n for Proposed Change The proposed change revises the acceptance c iteria for meeting the " ready-to-load" requirement denoted by SR 3.8.1.17 for the Division 3 DG. The proposed change reflects j
the need to credit manual action in satisfying the acceptance criteria for what constitutes
            " ready-to-load" during the performance of SR 3.8.1.17.
During the initial licensing of CPS, information was provided relating to the starting and accelerating characteristics of the Division 3 DG. This information was provided in
!'        . Licensing Topical Report NEDO-10905, "High-Pressure Core Spray System Supply Unit," and was reviewed and approved by the NRC as documented in the initial CPS SER.
The report provided specific exceptions to regulatory standards and requirements            i reviewed by the NRC during initiallicensing. Sections 5 and 7 ofNEDO-10905 provided          ;
design information regarding the governor design and operation. The design of the .          !
l Division 3 DG includes a mechanical governor. The droop mode of operation is used            j when the DG is operating in parallel with another source. The droop mode permits the l
i load to be shared between the two power sources. The Division 3 DG, with its                !
mechanical governor design, always operates in a droop mode.                                  1 In the test mode, the engine governor speed droop control is set to 50 to assure that        ,
frequency is maintained within limits during performance of the DG tests. Since the droop      ,
control setting is not automatically overridden or reset to 0 while in the test mode, manual operator action is necessary to reset the governor, including the droop control setting, during the performance of SR 3.8.1.17.
With the droop control setting at 50, the generator operating frequency is reduced by about 3% to approximately 58.2 hertz. The generator frequency required to supply the connected loads during a LOCA is 60 hertz. At a droop control setting of 0, the generator operating frequency is 60 hertz. Ifmanual action to reset the droop control setting were not performed during SR 3.8.1.17, the Division 3 DG would not provide the frequency            j required for proper operation of the connected loads. With the Division 3 DG dedicated        !
j        - to supplying power to the HPCS pump motor and the loads that support operation of the        ;
                                                                                                        ~
;          - associated pump, the reduced frequency of 58.2 hertz (with the droop control set at 50 ll        . and no operator action to increase speed) would cause the HPCS motor and pump to operate ati slower speed. This would reduce the flow rate from the HPCS pump to less than the Technical Specification required flow rate.
The CPS TS surveillance requirement issued during initial licensing (TS 4.8.1.1.2.e.11) stated: " Verifying that, with the diesel generator operating in a test mode and connected to its bus, a simulated ECCS actuation signal overrides the test mode and returns the
          ' diesel generator to standby operation, and automatically energizes the emergency loads with offsite power." When CPS incorporated the Improved Technical Specifications (ITS), the revised surveillance requirement (SR 3.8.1.17) stated: " Verify, with a DG
          . operating in test mode and connected to its bus, an actual or simulated ECCS initiation signal overides the test mode by returning DG to ready-to-load operation." The Bases W_=____.      _ _ _ _ _ _ _ _ _ _ _ -
 
l N                                                                                                                                      Attachment 2                        4 I
to U-603067 I
LS-98-010 Page 4 of 6 supporting the SR stated: " Interlocks to the LOCA sensing circuits cause the DG to
(
automatically reset to ready-to-load operation if an ECCS initiation signal is received during operation in the test mode. Ready-to-load operation is defined as the DG running at rated speed and voltage with the DG output breaker open." The initial TS required only returning the DG to standby operation. This requirement was met prior to the incorporation of the ITS since there were no restrictions in the TS surveillance or Bases that prevented a manual reset of the governor, including the droop control. The acceptance criteria in the current TS specifically states that the DG is automatically reset to ready-to-load operation. Therefore literal compliance would preclude manual operator action to reset the governor to satisfy this surveillance requirement.
              - The USAR and the NRC SER (NUREG 0853, February 1982) references the NRC's                                                                                      !
review and acceptance of NEDO-10905. CPS believes that the current design of the                                                                                l
: Division 3 DG, specifically regarding the manual operator action to reset the governor, is sufficient to meet its intended safety function. There are adequate procedural controls in place to ensure manual reset of the governor following receipt of an ECCS signal.
In lieu of these procedural controls, the Division 3 DG would have to undergo significant                                                                      I design modifications to eliminate the need for manual reset of the governor. These modifications would include replacement of the DG governor.-
Significant Hazard * '%nsideration In accordance with 10CFR 50.92, a proposed change to the operating license involves no significant hazards consideration if operation of the facility in accordance with the proposed change would not: (1) involve a significant increase in the probability or                                                                            !
consequences of any accident previously evaluated, (2) create the possibility of a new or different kind of accident from any accident previously evaluated, or (3) involve a significant reduction in a margin of safety.
(1)          . The proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.                                                                                          ,
                            . The proposed change revises the acceptance criteria for meeting the " ready-to-load" requirement denoted by TS Surveillance Requirement (SR) 3.8.1.17 for the Division 3 Diesel Generator (DG). The proposed change also adds a discussion of L                                    this acceptance criterion to the USAR to clarify the intent of the requirement. The                                                          '
l proposed change allows manual operator action to reset the governor upon receipt
!.                                    of an ECCS signal. Analyzed events are considered to be initiated by the failure of l                                    plant structures, systems, or components. The DGs are not considered as initiators of any analyzed event. The proposed change does not have a detrimental impact on the condition or performance of any plant structure, system, or component that                                                            ,
initiates an analyzed event. The proposed change will not alter the operation of or                                                        !
otherwise increase the failure probability of any plant equipment that initiates an t                                      analyzed event.' As such, the probability of occurrence for a previously analyzed accident is not significantly increased.
L L___ ____              _ _ _ _ _ _ _ _ _ _ . - - _ _ _ _ _ - . _ - . . ----- ---    - _ _ _ _ _ _ _ _ . - - - - - - - - - - - - - - - _ .        - - - - - - - --___ _ - . _ _
 
N                                                                                                                  Attachment 2 to U-603067 L                                                                                                                      LS-98-010 Page 5 of 6 The consequences of a previously analyzed event are dependent on the initial i                conditions assumed for the analysis, the availability and successful functioning of I
the equipment assumed to operate in response to the analyzed event, and the setpoints at which these actions are initiated. The Division 3 DG continues to overide the test mode and return the DG to a standby operation. The manual operator action to reset the governor following the receipt of an ECCS signal, continues to ensure that the equipment being powered by the DG will perform its intended function. The proposed change continues to ensure that the Division 3
!                DG will adequately support its design basis performance and mitigative function l                during an accident. Since the manual operator action performed during the test i
mode ensures that the governor is reset upon receipt of an ECCS signal, no analyses assumptions are violated and there are no adverse effects on the factors that contribute to offsite or onsite dose as the result of an accident. The proposed                                )
change does not affect setpoints that initiate protective or mitigative actions. The                                l" proposed change ensures that plant structures, systems, or components are
;                maintained consistent with the safety analysis and licensing bases. Based on this I
evaluation, there is no significant increase in the consequences of a previously                                      l analyzed event.
l
                                                                                                                                    )
Therefore, this change will not involve a significant increase in the probability or                                  ,
consequences of any accident previously evaluated.                                                                  1 J
I (2)      The proposed change would not create the possibility of a new or different kind of accident from any accident previously evaluated.                                                                  -)
i The proposed change revises the acceptance criteria for meeting the " ready-to-load" requirement denoted by TS SR 3.8.1.17 for the Division 3 DG. The proposed change also adds a discussion of this acceptance criterion to the USAR to clarify the intent of the requirement. The proposed change does not change the L                operating characteristics or the safety function of the DG. The DG performs a mitigative function. No new or different equipment is being installed and no installed equipment, which might initiate an analyzed event, is being opersted in a different manner. The proposed change does not impact core reactivity or the manipulation of fuel bundles. There is no alteration to the parameters within which the plant is normally operated or in the setpoints that initiate protective or mitigative actions. As a result no new failure modes are being introduced. There are no changes in the methods governing normal plant operation, nor are the methods utilized to respond to plant transients altered.
Therefore, the proposed change does not create the possibility of a new or different kind of accident from any previously evaluated.
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: 8.                                                                                                            Attachment 2 to U-603067 LS-98-010 Page 6 of 6
                                    .(3)    The proposed change will not involve a significant reduction in the margin of        I safety.
l The margin of safety is established through the design of the plant structures,    I systems, and components, the parameters within which the plant is operated, and the establishment of the setpoints for the actuation of equipment relied upon to respond to an event. The proposed change revises the acceptance criteria for meeting the " ready-to-load". requirement denoted by TS SR 3.8.1.17 for the Division 3 DG. The proposed change also adds a discussion of this acceptance .
criterion to the USAR to clarify the intent of the requirement. The proposed change allows manual operator action to reset the governor upon receipt of an ECCS signal. This ensures that appropriate frequency limits are obtained and that the Division 3 DG can perform its intended function. Thus, the proposed change does not significantly impact the condition or performance of structures, systems, and components relied upon for accident mitigation. Additionally, the proposed      I change does not significantly impact any safety analysis assumptions or results. I
                                            ' Therefore, the proposed change does not involve a significant reduction in a margin of safety.
In summary, based on the above considerations, it is concluded that a significant hazard would not be introduced as a result of the proposed change, i.e., revising the acceptance criteria for meeting the " ready-to-load" requirement denoted by TS SR 3.8.1.17 for the Division 3 DG.
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Latest revision as of 10:04, 25 July 2021