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Category:TECHNICAL SPECIFICATIONS
MONTHYEARML20196D0241999-06-16016 June 1999 Proposed Tech Specs Re Reactivity Control Incorporating Operating Requirements That Are Consistent with NEDO-21231, Banked Position Withdrawal Sequence ML20206R8161999-05-11011 May 1999 Proposed Tech Specs Re HPCI & RCIC Surveillance Testing ML20206H9771999-05-0505 May 1999 Proposed Tech Specs Modifying Licensing Basis for EDG on- Site Diesel Fuel Storage Requirements & Corresponding TSs ML20207F1171999-03-0303 March 1999 Proposed Tech Specs Page 3/4.6-13 Re Reactor Vessel Matl Surveillance Program Withdrawal Schedule ML20237E0851998-08-24024 August 1998 Proposed Tech Specs Pages Supporting Proposed TS Amend Related to EDG AOT ML20236X7191998-07-31031 July 1998 Proposed Tech Specs Page 3/4.9-5 Re Suppl to EDG for Allowed Outage Time ML20249C7101998-06-26026 June 1998 Proposed Tech Specs Correcting Typos & Updating Bases ML20249B3231998-06-15015 June 1998 Revised Complete Set of TS Pages Re Relocation of Radioactive Effluent TS & Radiological Environ Monitoring Program to ODCM ML20217F9341998-03-26026 March 1998 Proposed Tech Specs Re EDG Allowed Outage Time ML20217H2791998-03-25025 March 1998 Proposed Tech Specs 3.6.A.1 & 4.6.A.1,pertaining to Primary Sys Boundary,Thermal & Pressurizations Limitations & Surveillance Requirements & Basis 3/4.6.A ML20203D4981998-02-20020 February 1998 Proposed Tech Specs Pages,Incorporating Ultimate Heat Sink Temperature of 75 F Into TS 3/4.5.B & Bases,As Required by Amend 173 ML20217K5691997-10-24024 October 1997 Proposed Tech Specs Page Adding Footnote Declaring One Containment Isolation valve,30-CK-432,operate for Limited Period Despite Not Being within IST Interval for Reverse Flow Testing ML20211G2311997-09-12012 September 1997 Proposed Tech Specs Re Radiological Environ Monitoring Program Moved to ODCM ML20210K4381997-08-0808 August 1997 Revised TS Pages 3/4.5-7,B3/4.5-6 & B3/4/.5-7 Requiring Verification That SBO-DG Is Operable Prior to Voluntarily Entering LCO ML20196J0041997-07-22022 July 1997 Proposed Revised TS Bases for Section 3.5.F,correcting Volume of Water Available in Refuel Cavity & Dryer/Separator Pool When Flooded to Elevation 114 Ft & Revising Torus Water Volume to Reflect Volume Above Min Pump NPSH ML20136J5501997-03-0707 March 1997 Proposed Tech Specs Rev for Section 3.10, Core Alterations Allowing Removal of Suspect Fuel Bundles Out of Planned Sequence ML20134C9671997-01-24024 January 1997 Proposed Tech Specs 2.0 Re Safety Limits ML20133A6511996-12-23023 December 1996 Proposed Revised Tech Specs 1.0 Re definitions,3.4 Re Standby Liquid Control sys,3.5 Re Core & Containment Cooling systems,3.7 Re Containment Systems & 3.9 Re Auxiliary Electrical Sys ML20132E5491996-12-10010 December 1996 Proposed Tech Specs Table 3.2.C.1 Re Instrumentation That Initiates Rod Blocks,Table 3.2.C.2 Re Control Rod Block Instrumentation Setpoints & Table 4.2.C Re Minimum Test & Calibr Frequency for Control Rod Blocks Actuation ML20135C1461996-11-26026 November 1996 Proposed Tech Specs,Modifying Definition 1.M, Primary Containment Integrity, to Include All Instrument Line Flow Check Valves to Make Definition Consisten W/Lco 3/4.7.A.2.a.4 ML20134K4361996-11-0707 November 1996 Proposed Tech Specs Re Installation of BWROG Enhanced Option 1A ML20117K6551996-09-0505 September 1996 Proposed Tech Specs,Providing Revised TS Pages 3/4.5-7 & 3/4.5-6 ML20116M1561996-08-12012 August 1996 Proposed Tech Specs to Plant TS Section 6.0,Administrative Controls & Sections 6.5.B.10.C & 6.14 of Util Quality Assurance Manual ML20111B4201996-05-0101 May 1996 Proposed Tech Specs,Reflecting Implementation of 10CFR50 App J,Option B ML20108C1071996-05-0101 May 1996 Proposed Tech Specs,Relocating Administrative Controls Re QA Review & Audit Requirements of Section 6 from Plant TS to Boston Edison QA Manual ML20111C2761996-05-0101 May 1996 Proposed Tech Specs 3.1.1 Re Reactor Protection Sys (Scram) instrumentation,3.2.C.1 Re Instrumentation That Initiates Rod Blocks & 3/4.4 Re Standby Liquid Control ML20108C0581996-05-0101 May 1996 Proposed Tech Specs Re Core Alteration to LCO & Surveillance Conditions Associated W/Secondary Containment ML20108A6561996-04-25025 April 1996 Proposed Tech Specs Re Part of Overall Effort to Improve Outage Performance at Plant ML20095E0771995-12-0808 December 1995 Proposed Tech Specs Bases Page B2-2,including GE11 GEXL Correlation Axial Power Profile & R-factor Ranges & Correcting Error in GE11 GEXL Correlation Mass Flux Range in GE Design ref,NEDE-31152-P, GE Fuel Bundle Designs ML20092A4421995-08-31031 August 1995 Corrected Tech Spec Page Re Reactor High Pressure Trip Setting ML20086K2661995-07-14014 July 1995 Proposed Tech Specs Re Section 2.1,Bases:Safety Limits; Section 3.3.C,scram Insertion Times & Section 4.11.C, Minimum Critical Power Ratio to Reflect Use of Advanced GE-11 Fuel Design in Cycle 11 ML20078R6221995-02-15015 February 1995 Proposed Tech Specs Substituting for Pages Contained in Proposed TS Amends Submitted Prior to 950130 Authorization ML20078N4861995-02-0909 February 1995 Proposed Tech Specs,Increasing Reactor High Water Level Isolation Trip Level Setting ML20077M6921995-01-0909 January 1995 Proposed Reformatted Tech Specs & Bases ML20078K8151994-11-22022 November 1994 Proposed TS Pages 3/4.2-20 & 3/4.2-35 Re Tables 3.2.C-1 & 4.2.C ML20078K7961994-11-22022 November 1994 Proposed Tech Specs Re Changes to MSIV Leakage Requirement ML20077A8991994-11-22022 November 1994 Proposed Tech Specs Re Suppression Chamber Water Level ML20077B1861994-11-22022 November 1994 Proposed Tech Specs 3.5.F,4.5.F.1 & 3.9.B.1 & 2 Re EDG Allowed out-of-svc Time ML20072T0521994-09-0606 September 1994 Proposed Tech Specs Modification to Append a of Operating License DPR-35 Re Maintenance of Filled Discharge Pipe ML20072S0501994-09-0606 September 1994 Proposed Tech Specs Re Instrumentation That Initiates Primary Containment Isolation & Initiates or Controls Core & Containment Systems ML20072S0081994-09-0606 September 1994 Proposed Tech Specs Re Primary Containment,Oxygen Concentration & Vacuum Relief ML20072S0861994-09-0606 September 1994 Proposed Tech Specs Re Standby Gas Treatment & Control Room High Efficiency Air Filtration Sys Requirements ML20069M3311994-06-0909 June 1994 Proposed Tech Specs,Increasing Allowed out-of-service Time from 7 Days to 14 Days for Ads,Hpci & RCIC Sys,Including Section 4.5.H, Maint of Filled Discharged Pipe ML20067B7111994-02-0909 February 1994 Proposed Tech Specs Revising Wording for Page 3 of License DPR-35,clarifying Words to Aid Operators & Removing Obsolete Mechanical Snubber Acceptance Criterion BECO-93-156, Proposed Tech Specs Requesting Changes Supporting 24 Month Fuel Cycle (Submittal 3)1993-12-10010 December 1993 Proposed Tech Specs Requesting Changes Supporting 24 Month Fuel Cycle (Submittal 3) ML20059A9361993-10-19019 October 1993 Proposed Tech Specs for Removal of Scram & Group 1 Isolation Valve Closure Functions Associated W/Msl Radiation Monitors BECO-93-132, Proposed Tech Specs Removing Low Condenser Vacuum Scram in Order to Reduce Spurious Scrams,Unnecessary Plant Transients & Turbine First Stage Pressure Setpoint1993-10-19019 October 1993 Proposed Tech Specs Removing Low Condenser Vacuum Scram in Order to Reduce Spurious Scrams,Unnecessary Plant Transients & Turbine First Stage Pressure Setpoint ML20046D0441993-08-0909 August 1993 Proposed Tech Specs,Proposing 24 Month Fuel Cycle ML20044G1331993-05-20020 May 1993 Proposed Tech Specs Reducing MSIV Low Turbine Inlet Pressure Setpoint from Greater than or Equal to 880 Lb Psig to Greater than or Equal to 810 Psig & Reducing Min Pressure in Definition of Run Mode from 880 Psig to 785 Psig BECO-93-016, Proposed TS 3.5.C,D & E Re k-infinity Factor,Spent Fuel Pool Storage Capacity & Max Loads Allowed to Travel Over Fuel Assemblies,Respectively1993-02-11011 February 1993 Proposed TS 3.5.C,D & E Re k-infinity Factor,Spent Fuel Pool Storage Capacity & Max Loads Allowed to Travel Over Fuel Assemblies,Respectively 1999-06-16
[Table view] Category:TECHNICAL SPECIFICATIONS & TEST REPORTS
MONTHYEARML20196D0241999-06-16016 June 1999 Proposed Tech Specs Re Reactivity Control Incorporating Operating Requirements That Are Consistent with NEDO-21231, Banked Position Withdrawal Sequence ML20206R8161999-05-11011 May 1999 Proposed Tech Specs Re HPCI & RCIC Surveillance Testing ML20206H9771999-05-0505 May 1999 Proposed Tech Specs Modifying Licensing Basis for EDG on- Site Diesel Fuel Storage Requirements & Corresponding TSs ML20205A1451999-03-23023 March 1999 Core Shroud Insp Plan ML20207F1171999-03-0303 March 1999 Proposed Tech Specs Page 3/4.6-13 Re Reactor Vessel Matl Surveillance Program Withdrawal Schedule ML20151S3851998-08-31031 August 1998 Long-Term Program:Semi-Annual Rept ML20237E0851998-08-24024 August 1998 Proposed Tech Specs Pages Supporting Proposed TS Amend Related to EDG AOT ML20236X7191998-07-31031 July 1998 Proposed Tech Specs Page 3/4.9-5 Re Suppl to EDG for Allowed Outage Time ML20249C7101998-06-26026 June 1998 Proposed Tech Specs Correcting Typos & Updating Bases ML20249B3231998-06-15015 June 1998 Revised Complete Set of TS Pages Re Relocation of Radioactive Effluent TS & Radiological Environ Monitoring Program to ODCM ML20217F9341998-03-26026 March 1998 Proposed Tech Specs Re EDG Allowed Outage Time ML20217H2791998-03-25025 March 1998 Proposed Tech Specs 3.6.A.1 & 4.6.A.1,pertaining to Primary Sys Boundary,Thermal & Pressurizations Limitations & Surveillance Requirements & Basis 3/4.6.A ML20203D4981998-02-20020 February 1998 Proposed Tech Specs Pages,Incorporating Ultimate Heat Sink Temperature of 75 F Into TS 3/4.5.B & Bases,As Required by Amend 173 ML20217K5691997-10-24024 October 1997 Proposed Tech Specs Page Adding Footnote Declaring One Containment Isolation valve,30-CK-432,operate for Limited Period Despite Not Being within IST Interval for Reverse Flow Testing ML20211N6871997-09-16016 September 1997 Rev 9 to Procedure 8.I.1.1, Inservice Pump & Valve Testing Program ML20211G2381997-09-15015 September 1997 Rev 8 to PNPS-ODCM, Pilgrim Nuclear Power Station Odcm ML20211G2311997-09-12012 September 1997 Proposed Tech Specs Re Radiological Environ Monitoring Program Moved to ODCM ML20216C0631997-08-29029 August 1997 Semi-Annual Long Term Program Schedule ML20210K4381997-08-0808 August 1997 Revised TS Pages 3/4.5-7,B3/4.5-6 & B3/4/.5-7 Requiring Verification That SBO-DG Is Operable Prior to Voluntarily Entering LCO ML20196J0041997-07-22022 July 1997 Proposed Revised TS Bases for Section 3.5.F,correcting Volume of Water Available in Refuel Cavity & Dryer/Separator Pool When Flooded to Elevation 114 Ft & Revising Torus Water Volume to Reflect Volume Above Min Pump NPSH ML20210K3551997-07-0101 July 1997 Rev 16 to Procedure 7.8.1, Water Quality Limits ML20136J5501997-03-0707 March 1997 Proposed Tech Specs Rev for Section 3.10, Core Alterations Allowing Removal of Suspect Fuel Bundles Out of Planned Sequence ML20134C9671997-01-24024 January 1997 Proposed Tech Specs 2.0 Re Safety Limits ML20133A6511996-12-23023 December 1996 Proposed Revised Tech Specs 1.0 Re definitions,3.4 Re Standby Liquid Control sys,3.5 Re Core & Containment Cooling systems,3.7 Re Containment Systems & 3.9 Re Auxiliary Electrical Sys ML20132E5491996-12-10010 December 1996 Proposed Tech Specs Table 3.2.C.1 Re Instrumentation That Initiates Rod Blocks,Table 3.2.C.2 Re Control Rod Block Instrumentation Setpoints & Table 4.2.C Re Minimum Test & Calibr Frequency for Control Rod Blocks Actuation ML20135C1461996-11-26026 November 1996 Proposed Tech Specs,Modifying Definition 1.M, Primary Containment Integrity, to Include All Instrument Line Flow Check Valves to Make Definition Consisten W/Lco 3/4.7.A.2.a.4 ML20134K4361996-11-0707 November 1996 Proposed Tech Specs Re Installation of BWROG Enhanced Option 1A ML20117K6551996-09-0505 September 1996 Proposed Tech Specs,Providing Revised TS Pages 3/4.5-7 & 3/4.5-6 ML20116M1561996-08-12012 August 1996 Proposed Tech Specs to Plant TS Section 6.0,Administrative Controls & Sections 6.5.B.10.C & 6.14 of Util Quality Assurance Manual ML20117K6611996-07-17017 July 1996 Rev 15 to PNPS Procedure 1.2.2 Administrative OPS Requirements ML20108C0581996-05-0101 May 1996 Proposed Tech Specs Re Core Alteration to LCO & Surveillance Conditions Associated W/Secondary Containment ML20111B4201996-05-0101 May 1996 Proposed Tech Specs,Reflecting Implementation of 10CFR50 App J,Option B ML20111C2761996-05-0101 May 1996 Proposed Tech Specs 3.1.1 Re Reactor Protection Sys (Scram) instrumentation,3.2.C.1 Re Instrumentation That Initiates Rod Blocks & 3/4.4 Re Standby Liquid Control ML20108C1071996-05-0101 May 1996 Proposed Tech Specs,Relocating Administrative Controls Re QA Review & Audit Requirements of Section 6 from Plant TS to Boston Edison QA Manual ML20108A6561996-04-25025 April 1996 Proposed Tech Specs Re Part of Overall Effort to Improve Outage Performance at Plant ML20095E0771995-12-0808 December 1995 Proposed Tech Specs Bases Page B2-2,including GE11 GEXL Correlation Axial Power Profile & R-factor Ranges & Correcting Error in GE11 GEXL Correlation Mass Flux Range in GE Design ref,NEDE-31152-P, GE Fuel Bundle Designs ML20100J2521995-11-22022 November 1995 Rev 7 to Pilgrim Nuclear Power Station Odcm ML20092B5861995-09-0101 September 1995 Rev 0 to Third Ten-Yr Interval ISI Plan for Pilgrim Nuclear Power Station ML20092C4331995-09-0101 September 1995 Startup Test Rept for Pilgrim Nuclear Power Station Cycle 11 ML20092A4421995-08-31031 August 1995 Corrected Tech Spec Page Re Reactor High Pressure Trip Setting ML20086K2661995-07-14014 July 1995 Proposed Tech Specs Re Section 2.1,Bases:Safety Limits; Section 3.3.C,scram Insertion Times & Section 4.11.C, Minimum Critical Power Ratio to Reflect Use of Advanced GE-11 Fuel Design in Cycle 11 ML20078R6221995-02-15015 February 1995 Proposed Tech Specs Substituting for Pages Contained in Proposed TS Amends Submitted Prior to 950130 Authorization ML20078N4861995-02-0909 February 1995 Proposed Tech Specs,Increasing Reactor High Water Level Isolation Trip Level Setting ML20077Q1181995-01-13013 January 1995 Owner'S Specification for Reactor Shroud Repair ML20077M6921995-01-0909 January 1995 Proposed Reformatted Tech Specs & Bases ML20077A8991994-11-22022 November 1994 Proposed Tech Specs Re Suppression Chamber Water Level ML20077B1861994-11-22022 November 1994 Proposed Tech Specs 3.5.F,4.5.F.1 & 3.9.B.1 & 2 Re EDG Allowed out-of-svc Time ML20078K7961994-11-22022 November 1994 Proposed Tech Specs Re Changes to MSIV Leakage Requirement ML20078K8151994-11-22022 November 1994 Proposed TS Pages 3/4.2-20 & 3/4.2-35 Re Tables 3.2.C-1 & 4.2.C ML20078N8421994-11-18018 November 1994 Rev 32 to Procedure 8.7.3, Secondary Containment Leak Rate Test 1999-06-16
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l ATTACHMENT B PROPOSED TECHNICAL SPECIFICATION PAGES l
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r 9409130388 940906 PDR ADOCK 05000293 p PDR
LIMITING CONDITION FOR OPERATION SURVEILLANCE REQUIREMENTS 3.7 Primary Containment 4.7 Primary Containment
- 3) Neither of the two position alarm systems, which annunciate in the Control Room when any vacuum breaker opening exceeds 3/32", ,
are in alarm.
- b. Any drywell-suppression chamber b. During each refueling interval:
vacuum breaker may be non-fully closed as determined by the (1) Each vacuum breaker shall be position switches provided that tested to determine that the the drywell to suppression disc opens freely to the touch h chamber differential decay rate and returns to the closed is demonstrated to be not position by gravity with no greater than 25% of the indication of binding.
differential pressure decay rate for the maximum llowable (2) Vacuum breaker position bypass area of 0.2ft switches and installed alarm systems shall be calibrated and
- c. Reactor operation may continue functionally tested.
provided that no more than 2 of the drywell-pressure (3) At least 25% of the vacuum suppression chamber vacuum breakers shall be visually breakers are determined to be inspected such that all vacuum inoperable provided that they breakers shall have been are secured or known to be in inspected following every '
the closed position. fourth refueling interval. If deficiencies are found, all
- d. If a failure of one of the two vacuum breakers shall be installed position alarm visually inspected and systems occurs for one er more deficiencies corrected.
vacuum breakers, reactor operation may continue provided (4) A drywell to suppression that a differential pressure chamber leak rate test shall decay rate test is initiated demonstrate that the immediately and performed every differential pressure decay 15 days thereafter until the rate does not exceed the rate failure is corrected. The test which would occur through a 1 shall meet the requirements of inch orifice without the l Specification 3.7.A.4.b. addition of air or nitrogen.
- 5. Oxvaen Concentration 5. Oxvaen Concentration
! a. The primary containment The primary containment oxygen i atmosphere shall be reduced to concentration shall be measured less than 4% oxygen by volume and recorded at least twice with nitrogen gas during weekly.
reactor power operation with reactor coolant pressure above i 100 psig, except as specified l in 3.7.A.5.b.
Revision Amendment No. 681 -871 -149 157
l l BASES:
3.7.A & 4.7.A Primary Containment ,
I Vacuum Relief i The purpose of the vacuum relief valves is to equalize the pressure between the drywell and suppression chamber and reactor building so that the structural integrity of the containment is maintained. The vacuum relief system from the pressure suppression chamber to reactor building consists of two 100% vacuum relief breakers (2 parallel sets of 2 valves in series).
Operation of either system will maintain the pressure differential less than 2 4 psig; the external design pressure. One valve may be out of service for I repairs for a period of seven days. If repairs cannot be completed within seven days, the reactor coolant system is brought to a condition where vacuum relief is no longer required.
The capacity of the 10 drywell vacuum relief valves is sized to limit the pressure differential between the suppression chamber and drywell during post-accident drywell cooling to the design limit of 2 psig. They are sized on the basis of the Bodega Bay pressure suppression system tests. The ASME Boiler and Pressure Vessel Code,Section III, Subsection B, for this vessel allows a 5 psig vacuum; therefore, with two vacuum relief valves secured in the closed position and eight operable valves, containment integrity is not impaired.
l Reactor operation is permissible if the bypass area between the primary l containment drywell and suppression chamber does not exceed an allowable area.
l The allowable bypass area is based upon analysis considering primary system ,
l break area, suppression chamber effectiveness, and containment design i pressure. Analyses show that the maximum allowable bypass area is 0.2 fta, i l which is equivalent to all vacuum breakers open 3/32". (See letters from Boston Edison to the Directorate of Licensing, dated May 15, 1973 and October 22, 1974)
Reactor operation is not permitted if differential pressure decay rate is demonstrated to exceed 25% of allowable, thus providing a margin of safety for the primary containment in the event of a small break in the primary system. '
Each drywell suppression chamber vacuum breaker is equipped with three switches. One switch provides full open indication only. Another switch !
provides closed indication and an alarm should any vacuum breaker come off l l its closed seat by greater than 3/32". The third switch provides a separate i and redundant alarm should any vacuum breaker come off its closed seat by l l greater than 3/32". The two alarms above are those referred to in Section i 3.7.A.4.a(3) and 3.7.A.4.d. l l
The water in the suppression chamber is used only for cooling in the event of an accident; i.e., it is not used for normal operation; therefore, a daily check of the temperature and volume is adequate to assure that adequate heat removal capability is present.
Revision Amendment No. 113, 170 i
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ATTACHMENT C
! CURRENT TECHNICAL SPECIFICATION PAGES
- ANNOTATED WITH PROPOSED CHANGES i
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LIMITING CONDITION FOR OPERATION SURVEILLANCE RE0VIREMENTS 3.7 Primary Containment 4.7 Primary Containment
- 3) Neither of the two position alarm systems e C ' rd,which annunciate Pasi 005 when any vacuum- " 1 m N M ,d/ b breaker opening exceeds 3/32") are in alarm.
- b. Any drywell-suppression chamber b. During each refueling vacuum breaker may be non-fully interval:
closed as determined by.the position switches provided that (1) Each vacuum breaker shall be-the drywell to suppression tested to determine that the chamber differential decay rate disc opens freely to the touch is demonstrated to be not and returns to the closed greater than 25% of the position by gravity with no differential pressure decay indication of binding, rate for the maximum llowable bypass area of 0.2ft (2) Vacuum breaker position switches and installed alarm
- c. Reactor operation may continue systems shall be calibrated and provided that no more than 2 of functionally tested, the drywell-pressure suppression chamber vacuum (3) At least 25% of the vacuum breakers are determined to be breakers shall be visually a inoperable provided that they inspected such that all vacuum are secured or known to be in breakers shall have been the closed position. inspected following every fourth refueling interval. If l
- d. If a failure of one of the two deficiencies are found, all installed position alarm vacuum breakers shall be systems occurs for one or more visually inspected and vacuum breakers, reactor deficiencies corrected.
operation may continue provided that a differential pressure (4) A drywell to suppression decay rate test is initiated chamber leak rate test shall immediately and performed every demonstrate that the 15 days thereafter until the differential pressure decay failure is corrected. The test rate does not exceed the rate shall meet the requirements of which would occur through a 1 Specification 3.7.A.4.b. inch orifice without the addition of air or nitrogen.
- 5. Oxvaen Concentration
- 5. Oxvoen Concentration
- a. The primary containment atmosphere shall be reduced to The primary containment oxygen less than 4% oxygen by volume concentration shall be measured with nitrogen gas during and recorsled at least twice reacter power operation with weekly.
reactor coolant pressure above 100 psig, except as specified in 3.7.A.5.b.
Revision 168 Amendment No. 68,-87, 149 157
BASES:'
3 7.A & 4.7.A Primary Containment
'ecuum Relief ihe purpose of the vacuum relief valves is to equalize the pressure between the drywell and suppression chamber and reactor building so that the structural integrity of the containment is maintained. The vacuum relief system from the pressure suppression chamber to reactor building consists of 4 teo 100% vacuum relief breakers (2 parallel sets of 2 valves in series). '
Operation of either. system will maintain the pressure differential less than 2 psig; the external design pressure. One valve may be out of service for repairs for a period of seven days. If repairs cannot be completed within seven days, the reactor coolant system is brought to a condition where vacuum !
relief is no longer required. -
l The capacity of the 10 drywell vacuum relief valves is sized to limit the pressure differential between the suppression chamber and drywell during post-accident drywell cooling to the design limit of 2 psig. They are sized on the basis of the Bodega Bay pressure suppression system tests. The ASME Boiler and Pressure Vessel Code,Section III, Subsection B, for this vessel l allows a 5 psig vai.uum; therefore, with two vacuum relief valves secured in l the closed position and eight operable valves, containment integrity is not impaired.
Reactor operation is permissible if the bypass area between the primary containment drywell and suppression chamber does not exceed an allowable area. The allowable bypass area is based upon analysis considering primary system break area, suppression chamber effectiveness, and containment design ressure. Analyses show that the maximum allowable bypass area is 0.2 ft2 ,
hich is equivalent to all vacuum breakers open 3/32". (See letters from Boston Edison to the Directorate of Licensing, dated May 15, 1973 and October 22, 1974)
Reactor operation is not permitted if differential pressure decay rate is demonstrated to exceed 25% of allowable, thus providing a margin of safety for l the primary containment in the event of a small break in the primary system.
Each drywell suppression chamber vacuum breaker is equipped with three 1 suitches. One switch provides full open indication only. Another switch ;
provides closed indication and an alarm ee N el C ' should any vacuum breaker come off its closed seat by greater than 3/32". The third switch provides a separate and redundant alarm e ;- M 905 should any vacuum breaker come off its closed seat by greater than 3/32". The two alarms above are those referred to in Section 3.7.A.4.a(3) and 3.7.A.4.d.
The water in the suppression chamber is used only for cooling in the event of an accident; i.e., it is not used for normal operation; therefore, a daily check of the temperature and volume is adequate to assure that adequate heat removal capability is present.
Revision 116 Amendment No. 113 170