ML20237G681
| ML20237G681 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 08/21/1987 |
| From: | Kintner L Office of Nuclear Reactor Regulation |
| To: | Kingsley O SYSTEM ENERGY RESOURCES, INC. |
| References | |
| NUDOCS 8709020367 | |
| Download: ML20237G681 (16) | |
Text
'
s August 21, 1987 Docket No. 50-416 DISTRIBUTION 1 ecketAFile; J. Partlow D
NRC & Local PDRs Tech Branch Mr. Oliver D. Kingsley, Jr.
PD22 Reading ACRS (10)
Vice President, Nuclear Operations S. Varga Gray File Systen Energy Resources, Inc.
G. Lainas J. Mauck P.O. Box 23054 D. Miller T. Collins Jackson, Mississippi 39205 L. Kintner J. Kudrick OGC-Bethesda
Dear Mr. Kingsley:
E. Jordan
SUBJECT:
GRAND GULF NUCLEAR STATION (GGNS), UNIT 1 - CHANGES TO TECHNICAL SPECIFICATIONS FOR ATWS-RELATED SYSTEMS By letter dated August 13, 1987, System Energy Resources, Inc. (the licensee) submitted an application for an amendment to the operating license for GGNS Unit 1.
The amendment would change the Technical Specifications to reflect plant modifications being made to comply with requirements in 10 CFR 50.62
" Requirements for Reduction of Risk from Anticipated Transients Without Scram (ATWS) Events for Light-water Cooled Nuclear Power Plants.". The NRC staff is reviewing the application and finds that additional information as identified in the enclosure is needed to complete its review.
In order to support the review schedule, you are requested to provide the additional infonnation identified in the enclosure by August 31, 1987.
The reporting and/or recordkeeping requirements of this letter affect fewer than 10 respondents; therefore, OMB clearance is not required under P.L.96-511.
Sincerely,
/s/
Lester L. Kintner, Project Manager Project Directorate 11-2 Division of Reactor Projects-I/II
Enclosure:
As stated cc: See next page (I,-2 PM 2
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UNITED STATES y
' 'n NUCLEAR REGULATORY COMMISSION e
j WASHINGTON, D. C. 20555 August 21, 1987
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Docket No. 50-416 Mr. Oliver D. Kingsley, Jr.
j Vice President, Nuclear Operations l
System Energy Resources, Inc.
]
P.O. Box 23054
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I Jackson, Mississippi 39205
Dear Mr. Kingsley:
SUBJECT:
GRAND GULF NUCLEAR STATION (GGNS), UNIT 1 - CHANGES TO TECHNICAL SPECIFICATIONS FOR ATWS-RELATED SYSTEMS
- - By letter dated August 13, 1987, System Energy Resources, Inc. (the licensee) submitted an application for an amendment to the operating license for GGNS Unit 1.
The amendment would change the Technical Specifications to reflect plant modifications being made to comply with requirements in 10 CFR 50.62
" Requirements for Reduction of Risk from Anticipated Transients Without Scram (ATWS) Events for Light-water Cooled Nuclear Power Plants." The NRC staff is reviewing the application and finds that additional inforrnation as identified in the enclosure is needed to complete its review.
In order to support the review schedule, you are requested to provide the additional infonnation identified in the enclosure by August 31, 1987.
The reporting and/or recordkeeping requirements of this letter affect fewer j
than 10 respondents; therefore, OMB clearance is not required under P.L.96-511.
{
Sincerely, Lester L. Kintner, Project Manager Project Directorate 11-2 Division of Reactor Projects-I/II
Enclosure:
As stated cc: See next page l
i J
Mr. Oliver D. Kingsley, Jr.
System Energy Resources, Inc.
Grand Gulf Nuclear Station (GGNS) cc:
Mr. Ted H. Cloninger Mr. C. R. Hutchinson Vice President, Nuclear Engineering GGNS General Manager and Support System Energy Resources, Inc.
System Energy Resources, Inc.
Post Office Box 756 Post Office Box 23054 Port Gibson, Mississippi 39150 Jackson, Mississippi 39205 Robert B. McGehee, Esquire The Honorable William J. Guste, Jr.
Wise, Carter, Child, Steen and Caraway Attorney General j
P.O. Box 651 Department of Justice 1
Jackson, Mississippi 39205 State of Louisiana Baton Rourr, Louisiana 70804 Nicholas S. Reynolds, Esquire Bishop, Liberman, Cook, Purcell Of# ice of the Governor and Reynolds State of Mississippi 1200 17th Street, N.W.
Jackson, Mississippi 39201 Washington, D. C.
20036 Attorney General Mr. Ralph T. Lally Gartin Building l
Manager of Quality Assurance Jackson, Mississippi 39205 1
Middle South Utilities System Services, Inc.
P.O. Box 61000 Mr. Jack McMillan, Director l
New Orleans, Louisiana 70161 Division of Solid Waste Management Mississippi Department of Natural Mr. John G. Cesare Resources Director, Nuclear Licensing and Safety Bureau of Pollution Control System Energy Resources, Inc.
Post Office Box 10385 l
P.O. Box 23054 Jackson, Mississippi 39209 Jackson, Mississippi 39205 Alton B. Cobb, M.D.
Mr. R. W. Jackson, Project Engineer State Health Officer Bechtel Power Corporation State Board of Health 15740 Shady Grove Road P.O. Box 1700 l
Gaithersburg, Maryland 20877-1454 Jackson, Mississippi 39205 Mr. Ross C. Butcher President Senior Resident Inspector Claiborne County Board of Supervisors U.S. Nuclear Regulatory Commission Port Gibson, Mississippi 39150 Route 2, Box 399 Port Gibson, Mississippi 39150 Regional Administrator, Region II U.S. Nuclear Regulatory Commission 101 Marietta Street, N.W., Suite 2900 Atlanta, Georgia 30323 Mr. James E. Cross GGNS Site Director System Energy Resources, Inc.
P.O. Box 756 Port Gibson, Mississippi 39150
ENCLOSURE REQUEST FOR ADDITIONAL INFORMATION ATWS - RELATED SYSTEMS TECHNICAL SPECIFICATIONS
Reference:
SERI Letter dated August 13, 1987 1.
Paragraph B.4 of the reference letter states that no changes to Technical Specifications (TSs) are needed for the alternate rod injection (ARI) system. The staff is working with the BWR Owners Group to. develop Model TSs for ATWS-related systems, including the ARI system. Attached is a draft of model Technical Specifications for the ARI and recirculation pump trip (RPT) systems.
Provide revised proposed TSs for the GGNS-Unit 1 ARI and RPT systems using these draft model TSs as a guide.
2.
The proposed changes to TS 3/4.1.5 " Standby Liquid Control System" and the associated Bases do not reflect the change from a system with two redun-dant subsystems to a system that includes simultaneous operation of both pumps. Provide proposed TS changes to reflect the new SLCS system. Also describe testing of both pumps simultaneously to assure that a total flowrate of 82.4 gpm can be achieved without lifting of the SLCS relief valve.
3.
The proposed change to TS Page 3/4 1-20 uses a cross-hatched area on the temperature versus tank concentration chart to indicate the region of acceptable operation. This is not consistent with Emergency Procedure (EP) flow charts which indicate unacceptable operation with cross-hatched areas. Provide a proposed chart for the TSs consistent with the EP flow charts.
4.
Revise the analysis about the issue of no significant hazards considera-tion to address the following:
(a) The ARI system which will be connected to the RPT system when the modifications are made should be addressed for all three standards of 10 CFR 50.92.
(b) The effect of the modified SLCS piping design on the consequences of a LOCA with respect to bypassing of the suppression pool should be addressed.
(c) The reasons why the reduction in the margin between the proposed SLCS operating pressure and the relief valve setpoint is not signifi-cant, in consideration of the pulsations associated with simultaneous operation of the two pumps should be addressed.
(d) The reasons for the reduction in the margin between the proposed ARI/RPT reactor pressure-high trip setpoint and the nonnal scram path reactor pressure-high trip setpoint and why this reduction in margin is not significant should be addressed.
ATTACHi1ENT
( hygh ARI MDDEL TECHNICAL SPECIFICATIONS
- INSTRUMENTATION 3/4.3.XALTERNATERODINJECTIONACTUATIONINSTRUMENTATION LIMITlie CONDITION FOR OPERATION 3.3.X The anticipated transient withoot scram alternate rod injection (ATWS-ARI) system instrumentation channels shown in Tatie 3.3.X-1 shall be OPERABLE with their trip setpoints set consistent with values shown in the Trip Setpcint column of Table 3.3.X-?.
The ATWS-ARI manual and automatic actuation logic and actuation devices shall ifh OPERABLE.
{
APPLICABILITY: OPERATIONAL CONDITIONS 1 AND 2 ACTION:
a.
With an ATWS alternate rod injection system instrumentation channel trip setpoint less conservative than the value shown in the Allowable Values column of Table 3.3.X-2, declare the associated trip system inoperable until the channel is restored to OPERABLE status with its trip setpoint adjusted consistent with the Trip Setpoint value.
I b.
WiththenumberofOPERABLEinstrumentchannels(oneormore)less than the minimum number of OPERABLE channels requirement of Table 3.3.X-1 for both trip systems, restore at least one. trip system to OPERABLE status'within hours or be in Condition 3 within the next 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. With the manual initiation circuits or the automatic actuation logic or actuation device (s) inoperable, restore the inoper-
,ab)eequipmenttoOPERABLEstatuswithin hours or be in Condition 3 1
within the next 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
l 1
1
SURVEILLANCE REQUIREMENTS Each ATW5 alternate rod injection system instrumentation hhannel and the j
4.3.X.1 manual and automatic actuation logic and actuation devices shall be demonstrated OPERABLE by the performance of the CHANNEL CHECK, CHANNEL FUNCTIONAL TEST and CHANNEL CALIBRATION operations at-the frequencies shown in Table 4.3.X-1.
l I
4.3.X.2 An integrated test of all system components (i.e., all relays and contacts, all trip units, all solid, state logic components, etc.) from sensors through and including actuated devices shall be performed to verify OPERABILITY of the system function (s) at least once per fuel cycle during shutdown. This
' test shall include simulated automatic operation of all channels and shall verify OPERABILITY of all ARI solenoid valves.
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INSTRUMENTATION
-BASES 3/4.3.X ALTERNATE ROD INJECTION ACTUATION INSTRUMENTATION Tha OPERABILITY of the Alternate Rod Injection (ARI) System ensures that suffi-cient means are provided to limit the consequences.of anticipated transient without scram (ATWS) events. The ARl' system is designed to shutdown the reactor independent of the existing reactor trip system (RTS) under conditions indicative of an ATWS to prevent excessive suppression pool temperatures, thus ensuring plant safety. The ARI system is electrically diverse from the existing reactor trip system (RTS) logic and actuation circuitry, and therefore significantly reduces the potential for ATWS events caused by comon mode electrical failures j
in the RTS. The ARI system is required by the ATWS Rule (10 CFR 50.62, j
" Requirements for Reduction of Risk From Anticipated Transients Without' Scram (ATWS) Events for Light-Water-Cooled Nuclear Plants).
J The Technical Specification OPERABILITY requirements ensure that sufficient in-strumentation remains in service to provide adequate protection from ATWS events in accordance with the ATWS Rule.
If the OPERABILITY requirements cannot be met, the plant is placed in a limiting condition for operation (LCO) where appropriate ACTIONS must be taken to restore the inoperable ARI system instrumentation to an OPERABLE status within a specified time, or otherwise reactor operation is restricted to safe levels / modes where the ARI system safety function is no longer required.
The surveillance requirements specified for the ARI system instrumentation en-sure that the overall system functional capability and availability is main-The tained at a, level commensurate with the safety functions to be performed.
periodic suitveillance tests, when perfomed at the specified intervals, will assure that the necessary quality of systems and components is maintained to accomplish the desired safety functions when required.
c,
J SURVEILLANCE REQUIREMENTS Each ATWS -ec rculation pump trip system instrumentation channel and 4.3.4.1.1 the manual and automatic actuation logic and actuation devices shall be demon-strated OPERABLE by the performance,of the CHANNEL CHECK, CHANNEL FUNCTIONAL TEST and CHANNEL CALIBRATION operations at the frequencies shown in Table 4.3.4.1-1.
An integrated test of all ' system components (i.e., all relays and 4.3.4.1.2 contacts, all trip units, all solid state logic components, etc.)
from sensors through and including actuated devices shall be perfonned to verify OPERABILITY This test of the system function (s) at least once per fuel cycle during shutdown.
shall include simulated automatic operation *of all channels.
O 4
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ATW5 RPT MODEL TECHNICAL SPECIFICATIONS INSTRUMENTATION 3/4.3.4 RECIRCULATION PUMP TRIP AdTV'ATION INSTRUMENTATION ATWS RECIRCULATION PUMP TRIP SYSTEM INSTRUMENTATION
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LIMITING CONDITION FOR OPERATION 3.3.4.1 The anticipate.d transient without 4crem recirculation pump trip (ATW5-RPT) system instrumentation channels shown in Table 3.3.4.1-1 shall be OPERABLE with their trip setpoints set consistent with values shown in the Trip Setpoint column of Table 3.3.4.1-2.
Tne ATWS-RPT manual and automatic actuation logic and actuation devices shall be OPERABLE.
APPLICABILITY: OPERATIONAL CONDITION 1.
ACTION:
i With an ATW5 recirculation pump trip system instrumentation trip a.
setpoint let* conservative than the value shown in the Allowable j
Values column of Table 3.3.4.1-2, declare the associated trip system inoperable until the channel is restored to OPERABLE status with its trip setpoint adjusted consistent with the Trip Setpoint value.
i b;
With the number of OPERABLE instrument channels (one or more) less than the minimum number of OPERABLE channels requirement of Table 3.3.4.1-1, for both trip systems, restore at least one trip system to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> br be in Condition 3 within the next 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. With the manual initiation circuits or the automatic actuation logic or actuation device (s) inoperable, restore the inoperable equipment to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in Cowlitise 3 within the next 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />...
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INSTRUMENTATION 4
BASES 3/4.3.4 RECIRCULATION PUMP TRIP ACTUATION INSTRUMENTATION The anticipated transient without scram (ATWS) recirculation pump trip system provides a means of limiting the consequences of the unlikely occurrence of a failuce to scram during an anticipate ~d transient. The response of the plant to this postulated event falls within the envelope of study events in General Electric Company Topical Report NEDO-10349, dated March 1871, and Appendix (_)
The ATWS-RPT system is designed to provide a rapid reduction in
~ of the FSAR.
reactor power (from 100 percent to approximately 30 percent within one minute)
The ATWS-RPT is required following a transient event and a failure to scram.
by the ATWS Rule (10 CFR 50.62, " Requirements for Reduction of Risk from
~
Anticipated Transients Without Scram (ATWS) Events for Light-Water-Cooled NuclearPlants").
The Technical Specification OPERABILITY requirements ensure that sufficient in-strumentation remains in service to provide adequate protection from ATWS events in accordance with the ATWS Rule.
If the OPERABILITY requirements cannot be met, the plant is placed in a limiting condition for operation (LCO) where appropriate ACTIONS must be taken to restore the inoperable ATWS-RPT in-strumentation to an OPERABLE status within a specified time, or otherwise re-actor operation is restricted to safe levels / modes where the RPT safety function 1s no longer required.
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