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| document type = TECHNICAL SPECIFICATIONS, TECHNICAL SPECIFICATIONS & TEST REPORTS | | document type = TECHNICAL SPECIFICATIONS, TECHNICAL SPECIFICATIONS & TEST REPORTS | ||
| page count = 14 | | page count = 14 | ||
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Latest revision as of 03:37, 7 October 2021
ML20215K894 | |
Person / Time | |
---|---|
Site: | Farley ![]() |
Issue date: | 05/04/1987 |
From: | ALABAMA POWER CO. |
To: | |
Shared Package | |
ML20215K877 | List: |
References | |
NUDOCS 8705120025 | |
Download: ML20215K894 (14) | |
Text
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ATTACHMENT 1 Proposed Changes to Technical Specification Pages Unit 1 Revision Page 3/4 6-10 Replace Page 3/4 6-10a Add Page 3/4 6-10b Add
. Page B 3/4 6-2 Replace Page B 3/4 6-2a Add Unit 2' Revision
--Page 3/4-6-10 Replace Page 3/4 6-10a Add Page 3/4 6-10b- Add Page B 3/4 6-2 Replace Page B 3/4 6-2a Add n
8705120025 870504 PDR ADOCK 05000348 P PDR
V CONTAINMENT SYSTEMS CONTAINMENT VENTILATION SYSTEM LIMITING CONDITION FOR OPERATION.
....................==========..===================== ...========================
3.6 .1.7 Containment purge supply and exhaust valves shall be OPERABLE * ~and:
- a. The 48-inch' containment purge supply and exhaust isolation valves
- (CBV-HV-3198A, 31980, 3196, 3197) shall be de-activated and secured in their closed position.
- b. The 8-inch containment mini-purge supply and exhaust isolation valves (CBV-HV-2866C, 2866D, 2867C, 2867D) may be open for safety-related reasons.
APPLICABILITY: MODES 1, 2, 3 and 4 ACTION:
- a. With one 48-inch containment purge supply or one 48-inch containment purge exhaust isolation valve open or not de-activated, de-activate and secure in the closed position the open valve (s) or isolate the penetration within four hours or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />,
- b. With the _ leakage rate for the containment purge supply and exhaust penetrations exceeding the limit of Specification 4.6.1.7.2 or 4.6.1.7.3.a within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> either:
- 1. Reduce the leakage to within the limit, or
- 2. Isolate the containment purge supply or ooth supply and exhaust penetrations as required to reduce the leakage rate from the containment atmosphere to the outside atmosphere to within the limit of Specification 4.6.1.7.2 by the use of at least:
a) One OPERABLE de-activated 48-inch inside containment purge supply or both supply and exhaust isolation valves secured in the closed position or secured by use of a blind flange, and one OPERABLE de-activated 8-inch inside containment purge supply or both supply and exhaust isolation valves secured in the closed l
position or secured by use of a blind flange, or
- This specification is governing for the containment purge supply and exhaust isolation penetration leakage and 48-inch isolation valve position.
FARLEY-UNIT 1 3/4 6-10 AMENDMENT NO.
r CONTAINMENT SY3TEMS' CONTAINMENT VENTILA1 ION SYSTEM LIMITING CONDITION FOR OPERATION
=
b) One OPERABLE de-activated 48-inch outside containment purge supply or both supply and exhaust isolation valves secured in the closed position or secured by use of a blind flange, and one OPERABLE de-activated 8-inch outside containment purge supply or both supply and exhaust isolation valves secured in the closed position or secured by use of a blind flange, or
- 3. Be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
- c. With the leakage rate for containment purge supply or exhaust penetrations exceeding the limit of Specification 4.6.1.7.3.b, reduce the leakage to within the limit:
- 1. Prior to entering MODE 4 following the next COLD SHUTDOWN if the existing leakage is determined during quarterly testing pursuant to Specification 4.6.1.7.2, or
- 2. Prior to entering MODE 4 if excess leakage is determined during COLD SHUTDOWN pursuant to Specification 4.6.1.7.3.
SURVEILLANCE REQUIREMENTS
==================================- ============-----
4.6.1.7.1 The 48-inch containment purge supply and exhaust isolation valves shall be determined de-activated in the closed position at least once per 31 days.
4.6.1.7.2 At least once per 92 days, each penetration containing 8-inch and 48-inch containment purge supply and exhaust isolation valves with resilient material seals shall be demonstrated OPERABLE by verifying that when the leakage rates from degradation tests for both penetrations are added to the leakage rates determined pursuant to Specification 4.6.1.2.d for all other valves and penetrations subject to Type B and C tests, the combined leakage rate is less than or equal to 0.60 La-FARLEY-UNIT 1 3/4 6-10a AMENDMENT NO.
T .
T CONTAINMENT' SYSTEMS' .
CONTAINMENT VENTILATION SYSTEM.
SURVEILLANCE! REQUIREMENTS-(Continued)
'4.6.1.7.3 Each containment purge supply and-exhaust ^ penetration containing .
isolation valves with. resilient material seals shall be demonstrated OPERABLE prior to startup.after each' COLD SHUTDOWN, if not performed in the previous 92
-days, by verifying that:
1a)LWhen the' measured . leakage rate.is added to the leakage rates ' determined
, ' pursuant to Specification 4.6.1.2.d for all other valves and penetrations subject to Type B and C. tests, the combined leakage' rate is -
..l
'less than or equal to 0.60 La, and b) .The leakage . rate ~ for.each containment purge supply and exhaust' ,
. penetration is less -than or equal to 0.05 La.
1
'In addition, the: leakage. rate- for the containment- purge -isolation valves shall
. be compared to the previ ously measured -leakage' rate '(for the ' containment ; purge.
iisolation_ valves) to detect excess valve degradation. An engineering evaluation shall be performed to-determine what corrective action, if any, is' necessary..
4.6.1~.7.4 ' The re'silient materialivalve seals of the 48-inch and the 8-inch containment purge supply and exhaust isolation valves shall be replacsd at .least once per 5' years.
F 1
i i,. .
t
,f FARLEY-UNIT 1 3/4 6-10b AMENDMENT N0.
i
- g. . 9,
- ' CONTAINMENT SYSTEMS BASES' The maximum peak pressu~re expected to be .obtained from a LOCA-event is 45.
-psig., .The limit of t3'psig'.for initial positive containment: pressure will : limit the total pressure to 48 psig which is less than design pressure and is consistent with the accident analyses.-
3/4.6.1.5 AIR TEMPERATURE The' limitations on containment average air temperature ensure that the nov'erall containment average air temperature does not exceed the initial
~
temperature condition assumed in the accident analysis for a LOCA or steam line break accident.
3/4.6.1.6 CONTAINMENT STRUCTURAL INTEGRITY This-limitation ' ensures that the structural integrity of the containment will be maintained comparable to the original design standards for the life of
'the facility. - Structural; integrity is required to ensure that the containment will withstand the maximum pressure of:48 psig in the event of. a LOCA. The
- measurement 'of. the containment lift off force, visual examination of tendons, anchorages and exposed interior and exterior surfaces of the containment, and
-the Type A leakage test is sufficient to demonstrate this capability.
The surveillance requirements for demonstrating the containment's
~
structuraliintegrity are.in compliance with the recommendations of paragra'ph C.1.3 of Regulatory Guide 1.35 " Inservice Surveillance of Ungrouted Tendons in Prestressed Concrete Containment Structures," January 1976.
~
3/4.6.1.7 . CONTAINMENT VENTILATION' SYSTEM
. The 48-inch containment purge supply and -exhaust isolation valves are
~
- required to be closed in' MODES above COLD SHUTDOWN since these valves have not
-been demonstrated Lcapable of closing during a LOCA or steam line break .l accident. Maintaining these valves closed during plant operations ensures that L excessive quantities of-radioactive materials will-not.be released via the containment ' purge system.
The use of the containment purge lines is restricted to the 8-inch vent
. supply and exhaust isolation valves to ensure that the site boundary dose guidelines of'10 CFR Part 100.would not be exceeded in the event of a
~ loss-of-coolant accident during venting operations.
FARLEY- UNIT 1 B 3/4 6-2 AENDENT NO.
CONTAINMENT SYSTEMS
' BASES Safety-related reasons for venting containment during operation (MODES 1, 2, 3 and 4) include controlling containment pressure and reducing airborne radioactivity.
The purpose.of the quarterly degradation tests of the. isolation valves in the containment purge. supply and exhaust lines per Specification 4.6.1.7.2 is to identify excessive degradation of the resilient seals for these valves.
In addition,.these degradation tests are not subject to the requirements applicable to 10CFR50 Appendix J testing but are to be utilized to provide reasonable assurance that at least one set (inside containment or outside containmant) of isolation valves provides a. sufficient barrier to containment leakage. These degradation tests do not replace Appendix J testing, but are performed in addition to the Type C tests required by Appendix J. Type C testing that is conducted pursuant to Specification 4.6.1.7.3 will conform to the requirements of Appendix J. Failure to satisfy the containment purge supply and exhaust isolation valve leakage rate specifications while in MODES 1-4 will be governed exclusively by.the ACTION requirements of Specification 3.6.1.7 and not by other specifications.
The 12-hour time limit in ACTION Statement b provides the necessary time to confirm that containment integrity exists or to take appropriate corrective action. Isolation of a penetration with leakage in excess of the limit by use of an OPERABLE valve or a blind flange allows maintenance to be performed on the inoperable valve in that penetration. ACTION Statement b.2 requires a determination be made that the leakage rate from the containment atmosphere to the outside atmosphere is less than or equal to the margin available to 0.60 La; however, it does not require quantification of the leakage.
FARLEY-UNIT 1 B 3/4 6-2a AMENDMENT N0.
- CONTAINMENT SYSTEMS CONTAINMENT VENTILATION SYSTEM LIMITING CONDITION FOR OPERATION 3.6.1.7 _ Containment purge supply and exhaust valves shall be OPERABLE
- and:
- a. LThe 48-inch containment purge supply and exhaust isolation valves (CBV-HV-3198A,'31980,3196,3197) shall be_ de-activated and secured in their closed position.
- b. The 8-inch containment mini-purge supply and exhaust isolation valves -
(CBY-HV-2866C, 2866D, 2867C, 28670) may be open for safety-related reasons.
APPLICABILITY: MODES 1, 2, 3 and 4 ACTION:
- a. With one 48-inch containment purge supply or one 48-inch containment purge exhaust isolation valve open or not de-activated, de-activate and secure in the closed position the open valve (s) or isolate the penetration within four hours or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within:the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
- b. With the leakage rate for the containment purge supply and exhaust penetrations exceeding the limit of Specification 4.6.1.7.2 or 4.6.1.7.3.a within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> either:
- 1. Reduce the leakage to within the limit, or 2.. Isolate the containment purge supply or both supply and exhaust penetrations as required to reduce the leakage rate from the containment atmosphere to the outside atmosphere to within the limit of Specification 4.6.1.7.2 by the use of at least:
a) One OPERABLE de-activated 48-inch inside containment purge supply or both supply and exhaust isolation valves secured in the closed pcsition or-secured by use of a blind flange, and one OPERABLE de-activated 8-inch inside containment purge supply or both supply and exhaust isolation valves secured in the closed position or secured by use of a blind flange, or i
- This specification is governing for the containment purge supply and exhaust isolation penetration leakage and 48-inch isolation valve position.
FARLEY-UNIT 2 3/4 6-10 AMENDMENT NO.
-o .
_C')NTAINMENT SYSTEMS CONTAINMENT VENTILATION SYSTEM LIMITING' CONDITION FOR OPERATION b) One OPERABLE de-activated 48-inch outside containment purge supply or both supply and exhaust isolation valves secured in the closed position or secured by use of a blind flange..and one OPERABLE de-activated 8-inch outside containment purge supply or both supply and exhaust isolation valves secured in the
~
closed position or secured by use of a blind flange, or
- 3. Be in at least H0T STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
- c. With the leakage rate for containment purge supply or exhaust penetrations exceeding the limit of Specification 4.6.1.7.3.b, reduce the leakage to within the limit:
- 1. Prior to entering MODE 4 following the next COLD SHUTDOWN if the existing leakage is determined during quarterly testing pursuant to -
Specification 4.6.1.7.2, or
- 2. Prior to entering MODE 4 if excess leakage is determined during COLD SHUTDOWN pursuant to Specification 4.6.1.7.3.
SURVEILLANCE REQUIREMENTS
-- -=====----
4.6.1.7.1 The 48-inch containment purge supply and exhaust isolation valves shall be determined de-activated in the closed position at least once per 31 days.
4.6.1.7.2 At least once per 92 days, each penetration containing 8-inch and 48-inch containment purge supply and exhaust isolation valves with resilient material seals shall be demonstrated OPERABLE by verifying that when the leakage rates from degradation tests for both penetrations are added to the leakage rates determined pursuant to Specification 4.6.1.2.d for all other valves and penetrations subject to Type B and C tests, the combined leakage rate is less than or equal to 0.60 La-FARLEY-UNIT 2 3/4 6-10a AMENDMENT NO.
CONTAINMENT SYSTEMS CONTAINMENT VENTILATION. SYSTEM SURVEILLANCE REQUIREMENTS (Continued) 4.6.1.7.3 Each containment purge supply and exhaust penetration containing isolation valves with resilient material seals shall be demonstrated OPERABLE prior to startup after. each COLD SHUTOOWN, if not performed in the previous 92
. days,.by verifying that:
. a) When the measured leakage rate is added to the leakage rates determined pursuant to Specification 4.6.1.2.d for all other valves and penetrations subject to Type B and C tests, the combined leakage rate is less than or equal to 0.60 La, and b) The leakage rate for each containment purge supply and exhaust penetration is less than or equal to 0.05 La-
~
In addition,- the leakage rate for the containment purge isolation valves shall
- be compared to the previously measured leakage rate (for the containment purge isolation valves) to detect excess valve degradation. An engineering evaluation shall be performed to determine what corrective action, if any, is necessary.
4.6.1.7.4 The resilient material valve seals of the 48-inch and the 8-inch containment purge supply and exhaust isolation valves shall be replaced at.least once per 5 years.
FARLEY-UNIT 2 3/4 6-10b AMENDMENT N0.
, . ,. , - - ,n ,
4 CONTAINMENT SYSTEMS BASES
=====================================================================
The maximum peak pressure expected to be obtained from a LOCA event is 45 psig. The limit of 3 psig for initial positive containment pressure will limit the total pressure to 48 psig which is less than design pressure and is consistent with the accident analyses.
3/4.6.1.5 AIR TEMPERATURE
~.The limitations-'on containment average air temperature ensure that the overall containment average air temperature does not exceed the initial
. temperature condition assumed in the accident analysis for a LOCA or steam line break accident.
3/4.6.1.6 CONTAINMENT STRUCTURAL INTEGRITY This limitation ensures that the structural integrity of the containment will be maintained comparable to the original design standards for the life of the facility. Structural integrity is required to ensure that the containment will withstand the maximum pressure of 48 psig in the event of a LOCA. The visual examination of tendons,- anchorages and exposed interior and exterior surfaces of the containment, and the Type A leakage test, along with the data obtained from Unit 1 tendon surveillance, is sufficient to demonstrate this capability.
The surveillance requirements for demonstrating the containment's structural integrity are in compliance with the recanmendations of paragraph C.1.3 of Regulatory Guide 1.35 " Inservice Surveillance of Ungrouted Tendons in Prestressed Concrete Containment Structures," January 1976.
3/4.6.1.7 CONTAINMENT VENTILATION SYSTEM The 48-inch containment purge supply and exhaust isolation valves are required to be closed in MODES above COLD SHUTDOWN since these valves have not been demonstrated capable of closing during a LOCA or steam line break accident. Maintaining these valves closed during plant operations ensures that excessive quantities of radioactive materials will not be released via the containment purge system.
The use of the containment purge lines is restricted to the 8-inch vent i supply and exhaust isolation valves to ensure that the site boundary dose guidelines of 10 CFR Part 100 would not be exceeded in the event of a loss-of-coolant accident during venting operations.
FARLEY- UNIT 2 B 3/4 6-2 AMENDMENT N0.
l
i '.' :. .
CONTAINMENT-SYSTEMS
. BASES
=
Safety-related _ reasons 'for venting 'containnent during operation (MODES 1, .
2, 31and 4) include controlling containment pressureLand reducing airborne
- ' radioactivity.
The ' purpose off the quarterly degradation tests of the isolation valves in .
the containment purge supply and exhaust lines per Specification 4.6.1.7.2 is to identify excessive degradation of the resilient seals for these valves.
In addition, these degradation tests are not subject toLthe requirements applicable to 10CFRSO Appendix J testing but are to be utilized to provide '
reasonable assurance that' at least one set (inside containment or outside containment):of isolation valves provides a sufficient barrier to containment leakage. - These degradation tests do not replace Appendix J testing, but are performed in addition to the Type C tests required by Appendix J. Type C testing that is conducted pursuant.to Specification 4.6.1.7.3 will conform to the requirements of Appendix J. Failure to satisfy the containment purge supply and exhaust isolation valveLleakage rate specifications while in MODES 1-4 will be governed exclusively _ by the ACTION requirements of Specification 3.6.1.7 and-not by other specifications.
The 12-hour time . limit in ACTION Statement b provides the necessary time to confirm that containment integrity exists or to take appropriate corrective action. Isolation of a penetration with leakage in excess of the limit by use of an OPERABLE valve or a blind flange allows maintenance to be performed on the inoperable valve in that penetration. ACTION Statement b.2 requires a-determination be made that the leakage rate from the containment atmosphere to the outside atmosphere is less than or equal to the margin available to 0.60 La; however, it does not require quantification of the leakage.
FARLEY-UNIT 2 B 3/4 6-2a AMENDMENT N0.
ATTACHMENT 2 Significant Hazards Evaluation Pursuant to 10CFR50.92 For the Proposed Containment Vent and Purging Technical Specification Changes Proposed Changes ,
Revise Technical Specification and Bases 3/4.6.1.7 to require quarterly degradation tests of the isolation valves in the containment purge supply and exhaust lines to identify excessive degradation of the resilient seals for these valves..
Background
- By letter of June 19, 1986, the NRC provided proposed Technical Specification pages determined by the NRC to be acceptable to resolve and close out Multiplant Action B-24 and Farley Unit 2 License Condition 2.C.(17). These changes add a quarterly surveillance requirement to detect major degradation in the 8-inch and 48-inch containment purge supply and exhaust isolation valve penetrations. In addition, the leakage rate for each containment purge supply and exhaust ,
penetration will be verified to be less than or equal to 0.05 La prior to l startup after each Cold Shutdown if not performed in the previous 92 days. l Two editorial revisions are also provided with this submittal involving the Containment Ventilation System Technical Specification's bases in order to make the two units' Technical Specifications identical. Unit 1 page B 3/4 6-2 is changed to reflect the as built design of the plant utilizing 8-inch in lieu of 18-inch purge supply and exhaust isolation valves, to utilize the Unit 2 terminology of "in MODES above COLD SHUTDOWN," and to incorporate the reasons for safety-related containment venting during operation. These changes are consistent with the Technical Specification provided to Alabama Power Company by the NRC under Unit 2 License Amendment Number 34, issued May 17, 1984. The Unit 2 page B 3/4 6-2 discussion of the safety-related reasons for containment venting was moved to page B 3/4 6-2a to be consistent with the format of the Unit 1 Technical Specifications.
The purpose of the quarterly degradation tests of the isolation valves in the containment purge supply and exhaust lines per Specification 4.6.1.7.2 is to identify excessive degradation of the resilient seals for these valves.
In addition, these degradation tests are not subject to the requirements applicable to 10CFR50 Appendix J testing but are to be utilized to provide reasonable assurance that at least one set (inside containment or outside containment) of isolation valves provides a sufficient barrier to containment leakage. These degradation tests do not replace Appendix J testing, but are performed in addition to the Type C tests required by Appendix J. Type C testing that is conducted pursuant to Specification 4.6.1.7.3 will conform to the requirements of Appendix J. Failure to satisfy the containment purge supply and exhaust isolation valve leakage rate specifications while in MODES 1-4 will be governed exclusively by the Action requirements of Specification 3.6.1.7 and not by other specifications. The 12-hour time limit in Action Statement b provides the necessary time to confirm that containment integrity exists or to take appropriate corrective action. Isolation of a penetration with leakage in excess of the limit by use of an operable valve or a blind flange allows maintenance to be performed on the inoperable valve in that penetration.
i.
l I
Attachment 2 Page 2 Action Statement b.2 requires a determination be made that the leakage rate from the containment atmosphere to the outside atmosphere is less than or equal to the margin available to 0.60 La; however, it does not require quantification of the leakage.
The Farley Nuclear Plant purge system is composed of 48-inch main purge valves and 8-inch mini-purge bypass valves around the 48-inch valves. The 48-inch valves are maintained de-activated and closed in MODES 1-4. The mini-purge system is used at Farley Nuclear Plant for safety-related reasons. These reasons include controlling containment pressure and reducing airborne radioactivity.
Analysis Alabama Power Company has reviewed the requirements of 10CFR50.92 as they relate [
to the proposed changes to the Containment Vent and Purging Technical Specifications and considers these changes not to involve a significant hazards consideration. In support of this conclusion, the following analysis is provided:
- 1. The proposed changes will not increase the probability or consequences of an accident previously evaluated because the proposed change only -
adds a surveillance requirement to ensure valve seal integrity where one did not exist previously. The containment vent and purge isolation valves are designed to automatically close and provide containment isolation within the time previously analyzed in the accident analyses. This proposed change does not affect the valve closure time but provides added assurance of valve operability upon its closure.
Therefore, the probability or consequences of an accident previously evaluated will not be increased.
- 2. The proposed changes will not create the possibility of a new or different kind of accident from any accident previously evaluated because containment isolation has been considered in previously evaluated accidents. The additional surveillance requirements do not change the operation of the valves but ensure that the containment isolation capabilities are maintained. Thus, these proposed changes will not create the possibility of a new or different kind of accident from any accident previously evaluated.
- 3. The proposed changes will not involve a reduction in a margin of safety because the revised Technical Specifications continue to assure that the 10CFR50 Appendix J total containment leakage criteria of 0.60 La for Type B and C tests is met. Therefore, these proposed changes will not involve a reduction in a margin of safety.
_______ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ - . - - - _ _ _ _ J
- c. .
p.
~
f $
7 Y
. Attachment 2'
- Page.3 I -
' Conclusion Bas'ed upon the analysis provided herewith, Alabama Power Company has determined Ethat the. proposed changes to the Technical Specifications will not involve a'-
~
--significant increase in.the probability or consequences of.an accident
.previously evaluated, create the possibility of a new or different kind ~of accident ~ from any. accident previously. evaluated, or involve a significant reduction in a margin of safety.- Alabama Power Company has ' determined that
, these proposed changes meet'the requirements of 10CFR50.92(c) and do not involve a-significant hazards consideration.
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