ML20149J170
| ML20149J170 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| Issue date: | 07/22/1997 |
| From: | ILLINOIS POWER CO. |
| To: | |
| Shared Package | |
| ML20149J168 | List: |
| References | |
| NUDOCS 9707280092 | |
| Download: ML20149J170 (11) | |
Text
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. Attachment 4 i to U-602796 ,
LS-9 7-004 l Pr.g:1 cf 4 l
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AC Sources 4)perating 3.8.1 l
l 3.3 ELECTRICAL POWER SYSTEMS 3.8.1 AC Sources-Operating LCO 3.8.1 The following AC electrical power sources shall be OPERABE:
NOTE In response to low voltage concerns add essed in IP Letter U-602796 dated July 22,1997, and in accordance with an approved exemption from the requirements of General Design Criterion (GDC) 17 of 10 CFR 50 Appendix A, for the period up to and including October 15,1997, the LCO requirement for two qualified offsite sources may be satisfied with one qualified circuit and one circuit that does not strictly conform to the capacity and capability requirements of GDC 17. With two circuits that do not strictly conform to the capacity and capability requirements of GDC 17, however, both circuits shall be considered inoperable.
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- a. Two qualified circuits between the offsite transmission network and the onsite Class 1E AC l Electric Power Distribution System; and l 1
- b. Three diesel generators (DGs). i l
APPLICABILTlY: MODES 1,2, and 3.
NOTE Division 3 AC electrical power eources are not required to be OPERABE when IIigh Pressure Core Spray System is inoperable.
ACTIONS ,
l CONDITION RT. QUIRED ACTION COMPLETION TIME A. One offsite circuit A.I Perform SR 3.8.1.1 for Ihour inoperable. OPERABE offsite circuit. AND Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter AND A.2 Restore offsite circuit to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> OPERABE status.
AND 6 days frc.n discovery of failure to meet LCO (continued)
CLINTON 3.8-1 Amendment No.-94 9707280092 970722 P DP. ADOCK 05000461 P PDR
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' '* Attachment 4 to U-602796 LS-97-004
, Pegn 3 of 4 N AC Sources-Operating ho {l1a n PS * ^
3.8.1
,0,.c m*g/g ) g con b HI Onlf ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME .
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B. One required DG B.1 Perform SR 3.8.1.1 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> i inoperable. for OPERABLE offsite l circuit (s). AND l Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter 6N.R B.2 Declare required 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> from feature (s), supported discovery of by the inoperable OG, Condition B inoperable when the concurrent with redundant required inoperability of feature (s) are redundant inoperable. required feature (s) l AtLD I B.3.1 Determine OPERABLE 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> DG(s) are not inoperable due to common cause failure.
OE C 1.2 Perform SR 3.8.1.2 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> forOPERABLEDG(s).
AND B.4 Restore required DG 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to OPERABLE status.
i AND l 6 days from discovery of failure to meet LCO
- (continued)
CLINTON 3.8-2 Amendment No. 95
Attrehmeat 4 to U-602796
.. LS-97-004
, Pega 4 of 4
. AC Scurces-Operating
$0 Chanys 3.e.1 frovye/ ki conbhulf onlj.
ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME C. Two offsite circuits C.1 Declare required 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> from inoperable. feature (s) inoperable discovery of when the redundant- Condition C required feature (s) concurrent with are inoperable. inoperability of redundant required feature (s)
AN_Q C.2 Restore one offsite 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> circuit to OPERABLE status.
D. One offsite circuit D.1 Restore offsite 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> inoperable. circuit to OPERABLE status. !
AND M
One required DG inoperable. D.2 Restore required DG 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to OPERABLE status.
E. Two required DGs E.1 Restore one required 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> ;
l inoperable. DG to OPERABLE l
- status. M i 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> if Division 3 DG is inoperable ,
9 F. Required Action and F.1 Be in MODE 3. 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Associated Completion i
! Time of Condition A, AND
- B, C, D, or E not met.
F.2 Be in MODE 4. 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> (continued)
CLINTON 3.8-3 Amendment No. 95 i
e l e Attachment 5 to U-602796 LS-97 004 '
Page 1 of 4 Attached Marked-Up Pages of the Technical Specification Bases Changes l
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i. Attachment 5 to U-602796 LS-97-004 '
Page 2 of 4 AC Sources-Operating l B 3.8.1 i i
BASES (continued)
LCO Two qualified circuits between the offsite transmiss?cn network and the onsite Class 1E Distribution System and three separate and independent DGs (I A, IB, and IC),
ensure availability of the required power to shut down the retctor and maintain it in a safe shutdown condition after an anticipated operational occurrence (AOO) or a postulated DBA.
l Qualified offsite circuits are those that are described in the USAR and are part of the licensing basis for the unit.
I!ach offsite circuit must be capable of maintaining rated frequency and voltage, and acc(pting required loads during an accident, while connected to the ESF buses. Each offsite circuit consists ofincoming breaker and disconnect to the respective reserve j
4 auxiliary transformer (RAT) or emergency reserve auxiliary transformer (ERAT) and the l respective circuit path including feeder breakers to each of the 4.16 kV ESF buses
- Insert A 2
i Each DG must be capable of starting, accelerating to rated speed and voltage, and i cc nnecting to its respective ESF bus on detection of bus undervoltage. This sequence 2
- nust be accomplished within 12 seconds. Each DG must also be capable of accepting
- required loads within the assumed loading sequence intervals, and must continue to operate until offsite power can be restored to the ESF buses. These capabilities are required to be met from a variety ofinitial conditions such as DG in standby with engine hot and DG in standby with engine at ambient conditions. Additional DG capabilities must be demonstrated to meet required Surveillances, e.g., capability of the DG to revert to
- standby status on an ECCS signal while operating in parallel test mode.
l Proper sequencing ofloads, including tripping of nonessential loads, is a required i
i function for DG 1 A and DG 1B OPERABILITY.
The AC sources in one division must be separate and independent (to the extent
. possible) of the AC sources in the other division (s). For the DGs, the separation and
- independence are complete. For the offsite AC sources, the. separation and independence i are to the extent practical.
(continued)
CLINTON B 3.8-3 Revision No.-0
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- Attachment 5 to U-602796 l LS-97-004 Page 3 of 4 Insert A In response to low voltage concerns addressed in IP Letter U-602796 dated July 22,1997, and in accordance with an approved exemption from the requirements of General Design Criterion (GDC) 17 of 10 CFR 50 Appendix A, for the period up to and including October 15,1997, the LCO requirement for two qualified offsite sources may be satisfied with one qualified circuit and one circuit that does not strictly conform to the capacity and capability requirements of GDC 17. A circuit that does not strictly confonn to the capacity and capability requirements of GDC 17 is one for which voltage may be intermittently less then the minimum required for the plant. Acceptability of such a source is based, in part, on the capability to quickly restore voltage to the source if required, as may be effected through load shedding, etc. Acceptable voltages for the offsite circuits
, are based on actual voltage levels or a predictive model established to estimate, under various conditions, what the transmission system voltage should be in the event of a plant trip since such voltages are normally supported to higher levels with the plant on line.
While the exemption (and corresponding license amendment) is in effect, the following actions are required to be taken in the event that voltage on one or both offsite circuits is less than the minimum required based on the actual voltage level or as determined by the predictive model:
(1) With less than minimum required voltage for one offsite circuit during normal plant operation, plant operators shall coordinate with the IP electric dispatch center to be prepared to take musures to restore supply voltage. Mode changes are permitted with less than minimum required voltage for one offsite circuit.
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(2) With less than minimum required voltage for both offsite circuits during normal plant operation, the Required Actions for Condition C under TS 3.8.1 shall be entered. Entry into and exit from Condition C will be coincident with the 2 actual or predictive voltage values respectively being less than or greater than the minimum required voltage. Plant startup is not permitted with less than minimum required voltage on both offsite circuits. The total cumulative amount of time that Condition C is in effect shall be tracked.
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- Attachment 5 to U-6027%
LS-97-004 ,
- Page 4 of 4 i
BASES l
SURVEILLANCE Diesel Generator Test Schedule (continued)
REQUIREMENTS A test intervalin excess of 7 days (or 31 days, as appropriate) constitutes a failure to meet SRs and results in the associated DG being declared inoperable. It does not, however, constitute a valid test or failure of the DG, and any consecutive test count is not reset.
REFERENCES 1. 10 CFR 50, Appendix A, GDC 17.
- 2. USAR, Chapter 8.
- 4. USAR, Chapter 6.
- 5. USAR, Chapter 15.
- 7. Generic Letter 84-15, July 2,1984.
- 9. Regulatory Guide 1.108. I
I1. ANSI C84.1,1982.
- 12. NUMARC 87-00, Revision I, August 1991.
- 13. IEEE Standard 308.
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14 IP Calculation 19-AN-19.
- 15. IP Calculation 19-AQ-02.
- 16. NRC SER for IP Operating License Amendment 115.
CLINTON B 3.8-32 Revision No. 2-14 l
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$. Attachment 6 to U-602796 LS-97-004 Page 1 of 4 Attached Environmental Assessment 3
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. Attachment 6 to U-602796 4 LS-97-004 l Page 2 of 4 1
1 Environmental Assessment IP's request is based on granting a temporary partial exemption from the requirements contained in General Design Criterion 17," Electric Power Systems," of Appendix A to 10 CFR 50. With consideration and flexibility given to variations in design, siting and
. environmental conditions, the General Design Criteria of Appendix A to 10 CFR 50 establish minimum requirements for the principal design criteria for water-cooled nuclear power plants.
Licensing of Clinton Power Station (CPS) was based, in part, on the NRC's evaluation of the CPS design as it conforms to the General Design Criteria. The NRC's review, evaluation and acceptance of the design for the electric power system at CPS, as described in the CPS Final Safety Analysis Report, was documented in the CPS Safety Evaluation Report (NUREG 0853) issued to support licensing of the facility. Specific conformance of the design for the CPS onsite and offsite electric power systems to GDC 17 is thus i documented in the Safety Evaluation Report. IP's request to temporarily allow plant )
operation with one of the two offsite circuits intermittently having voltage that is less the minimum value conservatively established for CPS, would establish an operating ,
configuration that in not strictly in conformance with GDC 17. Specifically, an offsite !
source with voltage intermittently less than required, does not constitute a circuit having "suflicient capacity and capability" as required by GDC 17. Consequently, an exemption ]
is required from the requirement of GDC 17 stating,"The safety function for each system j
[i.e., the onsite and offsite electric power system] (assuming the other system is not I functioning) shall be to provide suflicient capacity and capability to assure that (1) l specified acceptable fuel design limits and design conditions of the reactor coolant pressure boundary are not exceeded as a result of anticipated operational occurrences and I (2) the core is cooled and containment integrity and other vital functions are maintained in the event of postulated accidents."
The Need for the Proposed License Amendment and Exemotion l
The proposed amendment and exemption is needed since strict application of the requirements of GDC 17 of Appendix A to 10 CFR 50, regarding the requirement for the offsite electric power system to have sufficient capacity andcapability, is not necessary to l achieve the underlying purpose of the rule and would impose undue hardships to IP.
Strict conformance to GDC 17 requires that the offsite circuit experiencing intermittent low voltages have sufficient capacity and capability such that voltage is maintained, on a continuous basis, above the minimum value conservatively established for CPS. IP has determined that all practical measures taken to boost voltage, short ofinterrupting service
4 Attachment 6 to U-602796 LS-97-004 Page 3 of 4 to customers, are not sufficient to maintain the minimum required voltage during all conditions. Further action to restore voltage would necessitate power interruptions. ;
In response to the intermittent voltage condition for the offsite electrical system due to the unusual conditions existing in the Illinois region this summer, IP has implemented measures to assess when the offsite electrical system voltage would be inadequate in the event of a plant trip, has performed an analysis to assess the risk associated with continued plant operation for the period of time within which the intermittent condition is likely to
- occur (i.e., until this fall), and has established (by practice) a reasonable recovery time to restore offsite system voltage in the event that it is needed (assuming a loss of the other offsite circuit).
Without the exemption, the offsite circuit experiencing intermittent periods oflower i than expected voltage would have to be considered inoperable. Plant startup or continued plant operation is not permitted with one offsite circuit inoperable.
EnvironmentalImpacts of the Proposed Amendment and Exemption :
Granting the exemptien and license amendment would not significantly increase the probability of unavailable offsite power in the event of an accident, and therefore, would ;
not significantly increase the probability of a radiological release frorn CPS. The j availability and reliability of the onsite power circuit would not be affected by the !
exemption / amendment. The availability and reliability of the offsite circuit having !
adequate voltage would also not be affected. Although there is a slight increase in the !
probability of having the low-voltage offsite circuit unavailable following a plant trip, or !
both sources unavailable in the event of a loss of the other offsite circuit, this increase is small based on the factors identified, and actions taken or that can be taken, by IP. On the assumption that electric power would still be available for safety-related equipment
- required to mitigate an accident, the proposed change does not involve an increase in the i
consequences of an accident.
1 With regard to potential nonradiological impacts, the proposed ext.mption/ amendment 4
would not affect the operation of the facility on the basis that adequate electric power will still be available to the facility during accident conditions, and particularly, during normal l
- operation. With no impact on plant operation, the proposed change does not impact
- nonradiological effluents and has no other environmentalimpact. With regard to IP's customers, the intent of the exemption / amendment is to permit continued plant operation,
- i. which will support grid voltage, without interrupting service to IP's customers, the latter of which could potentially have environmental and public safety impacts.
l l Alternative to the Proposed Action f
Given that there are no significant environmental effects associated with the proposed exemption / amendment beyond those attributed to operation of the facility, any alternatives i
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- Attachment 6 to U402796 LS-97-004 l Page 4 of 4 l (except to not allow operation of the facility) would have no greater, favorable !
environmentalimpact.
The principal alternative would be to deny the requested exemption / amendment. This would effectively preclude operation of the facility until the intermittent voltage condition j is resolved. Notwithstanding, IP has provided justification to support safe startup and (
operation of CPS. On the basis that safe plant operation isjustified, and given the fact that strictly imposing GDC 17 would not allow plant operation, the burden associated with strict compliance with GDC 17 is notjustified, particularly with respect to any environmentalimpact.
l Alternative Use of Resources The proposed amendment / exemption does not involve the use of any resources not previously considered in the " Final Environmental Statement Related to the Operation of ;
i Clinton Power Station, Unit 1," dated May 1982.
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