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| Additional loads have, been identified which should bemagnitude considered in the design of the suppression pool structures and equipment. The of these loads and their applicability to the SSES design bases have not been determined. | | Additional loads have, been identified which should bemagnitude considered in the design of the suppression pool structures and equipment. The of these loads and their applicability to the SSES design bases have not been determined. |
| SCOPE OF INTERIM REPORT: | | SCOPE OF INTERIM REPORT: |
| As required by 1OCFR50.55(e) this interim report is submitted to describe a " | | As required by 10CFR50.55(e) this interim report is submitted to describe a " |
| potential deficiency. which may have adverse affects on the Susquehanna Commission Steam Electric Station Units 1 and 2 (SSES). This report also advises the of the phenomena involved, provides a preliminary indication of implications, and describes corrective action underway. | | potential deficiency. which may have adverse affects on the Susquehanna Commission Steam Electric Station Units 1 and 2 (SSES). This report also advises the of the phenomena involved, provides a preliminary indication of implications, and describes corrective action underway. |
| IDENTXFICATXON OF POTENTXAL'DEFICIENCY: | | IDENTXFICATXON OF POTENTXAL'DEFICIENCY: |
|
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Category:Deficiency Report (per 10CFR50.55e and Part 21)
MONTHYEARML24255A8642024-09-0606 September 2024 Rscc Wire & Cable LLC Dba Marmon Industrial Energy & Infrastructure - Part 21 Retraction of Final Notification ML23279A0612023-10-0505 October 2023 Paragon Energy Solutions LLC, Part 21 Final Report Re Potential Defect with Eaton Jd and Hjd Series Molded Case Circuit Breakers (Mccbs) ML23254A0242023-09-0606 September 2023 Paragon Energy Solutions LLC, Potential Defect with Eaton Jd and Hjd Series Molded Case Circuit Breakers (Mccbs) ML23094A1252023-03-31031 March 2023 Talen Part 21 Final Notification P21-03032023-FN R0 Re Defect Identified in Automatic Transfer Switch ML23094A1242023-03-31031 March 2023 EN 56387 Update - Paragon Energy Solutions Final Notification of Defect of Automatic Transfer Switch ML23065A1962023-03-0202 March 2023 EN 56387 Paragon - Part 21 Report Re Defect Identified in Automatic Transfer Switch Pn: NLI-ATS480A400X1 ML20073G4572020-03-0909 March 2020 Carrier Corporation - Final Report Notification of Defect Pursuant to 10 CFR Part 21 for 17FA999-1200-107 Oil Pump ML19347A4262019-12-10010 December 2019 General Atomics - Reportable Occurrence Under 10CFR21: Reported Failure in Analog High Range Radiation Monitor (RP-2C) ML19120A1062019-04-17017 April 2019 Interim Report of Potential 10 CFR Part 21, Eaton Size 1 and 2 A200 Series Starters/Contactors ML18087A0022018-03-21021 March 2018 Crane Nuclear, Inc. - Final Report for 10 CFR Part 21 Investigation Report Notification of Xomox Plug Valve High Torsional Stress in Stem ML18078A5362018-01-31031 January 2018 Crane Nuclear, Inc. - Interim Report for 10 CFR Part 21 Investigation Report Notification of Xomox Plug Valve High Torsional Stress in Stem (Update) ML17311A9092017-10-31031 October 2017 Interim Report for Part 21 Investigation Report Notification of Xomox Plug Valve High Torsional Stress in Stem ML17223A1982017-07-21021 July 2017 Part 21 Notification - Eaton/Cutler Hammer A200 Series Starter ML17206A0402017-07-14014 July 2017 Part 21 - Defective Safety Related Valves PLA-7613, Interim Report of a Deviation, Units 1 & 2 - (PLA-7613)2017-06-0909 June 2017 Interim Report of a Deviation, Units 1 & 2 - (PLA-7613) ML17179A3782017-06-0707 June 2017 TE Connectivity - Part 21 Transfer of Information TE-023 ML17081A4532017-03-20020 March 2017 Part 21 - Plastic Jar Dedication Sampling ML17026A4142017-01-20020 January 2017 C&D Technologies, Inc. - Part 21 - Plastic Jar Dedication Sampling ML16313A0622016-10-18018 October 2016 C&D Technologies, Inc. - 10 CFR Part 21 Evaluation Regarding Terminal Welding Failure in 3DCU-9 Batteries ML16321A4502016-08-31031 August 2016 Part 21 Notification - Flowserve Swing Check Valves ML16039A2692016-02-0303 February 2016 Nutherm International, Inc. - Potential Issue Regarding Incorrect Industrial Irradiation Dose, Per Cooper, Oconee, Fitzpatrick, Point Beach, Brunswick, and Susquehanna ML15034A5662015-01-23023 January 2015 Notification of Potential Part 21 for Event #50703 ML15030A0332015-01-20020 January 2015 Letter from James Thigpen Notification of Potential Part 21 Nuclear Nonconformance Event Number 50703 ML14337A0942014-11-24024 November 2014 Notification of Potential Part 21 - Lack of Proper Power Supply Indication ML14329A0632014-11-19019 November 2014 Notification of Potential Part 21 Re Lack of Proper Power Supply Indication ML14274A0522014-09-22022 September 2014 Final Report 10CFR Part 21 Evaluation Regarding Misaligned Separators in LCR-25 Standby Batteries, Revision 1 - Original Letter Did Not Include the List of Affected Utilities ML14204A7072014-07-23023 July 2014 Completed Evaluation of Part 21 Potentially Reportable Condition Notification: Unseating of Valve Spring on SSPV ML14204A7082014-07-23023 July 2014 Enclosure 2, Description of Closure Evaluation, Non-Proprietary Information - Class I (Public) ML14210A0102014-07-23023 July 2014 Part 21 - Unseating of Valve Spring on Scram Solenoid Pilot Valve ML14169A0302014-06-15015 June 2014 Update to Interim Report - 10CFR 21 Evaluation Regarding Potential Deficiencies in Seismic Qualifications for PV-62 ML14303A5262014-03-28028 March 2014 Interim Part 21 Report - Misaligned Separators in LCR-25 Standby Batteries ML13340A3822013-12-0505 December 2013 Part 21 Reportable Condition Notification: Failure of Relay Logic Card Modules in 2 Out of 4 Voters ML13165A3422013-06-12012 June 2013 60-Day Interim Report Involving an Evaluation of a Design Change to Magne-Blast Circuit Breakers ML13042A0962013-02-0808 February 2013 Completed Evaluation of Part 21 Potentially Reportable Condition Notification: Error in Main Steam Line High Flow Calculational Methodology ML13044A0752013-02-0808 February 2013 Part 21 - Completed Evaluation for Potential Error in Main Steam Line High Flow Calculational Methodology ML12352A1232012-12-13013 December 2012 60-Day Interim Report Involving an Evaluation of a Design Change to Magne-Blast Circuit Breakers ML12348A1362012-12-13013 December 2012 Part 21 60-Day Interim Report Notification: Adequacy of Design Change in Am Magne-Blast Circuit Breakers ML12347A3082012-12-12012 December 2012 Part 21 60-Day Interim Report Notification: Error in Main Steam Line High Flow Calculational Methodology ML12319A0122012-09-27027 September 2012 Error in Main Steam Line High Flow Calculational Methodology ML12158A4472012-06-0606 June 2012 Part 21 60-Day Interim Report Notification - Closufailure of CRD Collet Retainer Tube/Outer Tube Weld ML12163A1302012-06-0606 June 2012 Part 21 Report - Failure of CRD Collet Retainer Tube/Outer Tube Weld ML12040A2832012-02-0707 February 2012 Notification of Potential Part 21 - Failure to Include Seismic Input in Reactor Control Blade Customer Guidance ML12038A0282012-02-0202 February 2012 Failure of CRD Collet Retainer Tube/Outer Tube Weld ML12032A2402012-02-0101 February 2012 Notification of Potential Part 21 - 60-Day Interim Report Notification: Failure of CRD Collet Retainer Tube/Outer Tube Weld ML11340A1002011-12-0505 December 2011 Letter 10 CFR Part 21 Notification Report, CON2000 and RTD2100 Spring Clips ML11341A0602011-12-0505 December 2011 Notification of Potential Part 21 Involving Defective Spring Clips Used as Seismic Restraints on Two Scientific Modules ML11363A1882011-12-0202 December 2011 10CFR21 Reporting of Defects and Non-Compliance - Engine Systems, Inc. Report No. 10CFR21-0098, Rev. 3, Amot Thermostatic Valve Element P/N: 9760X ML11336A3692011-12-0101 December 2011 Notification of Potential Part 21 Interim Report on Thermostatic Valve Failure on Palo Verde EDG ML11228A0842011-08-12012 August 2011 Notification of Part 21 - Failure to Include Seismic Input in Reactor Control Blade Customer Guidance ML1122401422011-08-11011 August 2011 Part 21 60-Day Interim Report Notification: Failure to Include Seismic Input in Channel-Control Blade Interference Customer Guidance 2024-09-06
[Table view] Category:Letter
MONTHYEARPLA-8142, Registration for the Use of Spent Fuel Storage Casks 306, 309, and 307 - PLA-81422024-09-18018 September 2024 Registration for the Use of Spent Fuel Storage Casks 306, 309, and 307 - PLA-8142 PLA-8141, Response to Request for Additional Information Regarding Relief Request 1RR06, PLA-81412024-09-18018 September 2024 Response to Request for Additional Information Regarding Relief Request 1RR06, PLA-8141 ML24260A2312024-09-17017 September 2024 Senior Reactor and Reactor Operator Initial License Examinations 05000387/LER-2024-002, B Diesel Generator Inoperable Due to Failed Excitation System Linear Reactor2024-09-16016 September 2024 B Diesel Generator Inoperable Due to Failed Excitation System Linear Reactor ML24255A8642024-09-0606 September 2024 Rscc Wire & Cable LLC Dba Marmon Industrial Energy & Infrastructure - Part 21 Retraction of Final Notification ML24249A1362024-09-0404 September 2024 EN 57304 - Westinghouse Electric Company, LLC, Final Report - No Embedded Files. Notification of the Potential Existence of Defects Pursuant to 10 CFR Part 21 ML24233A2192024-09-0303 September 2024 – Authorized Alternative to Requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code IR 05000387/20240052024-08-29029 August 2024 Updated Inspection Plan for Susquehanna Steam Electric Station, Units 1 and 2 (Report 05000387/2024005 and 05000388/2024005) 05000387/LER-2023-004, Manual Reactor Scram Due to Degraded Main Condenser Vacuum2024-08-26026 August 2024 Manual Reactor Scram Due to Degraded Main Condenser Vacuum 05000387/LER-2024-001, Main Steam Isolation Valve Leakage Due to Valve Body Seat Wear2024-08-21021 August 2024 Main Steam Isolation Valve Leakage Due to Valve Body Seat Wear IR 05000387/20240022024-08-12012 August 2024 Integrated Inspection Report 05000387/2024002 and 05000388/2024002 ML24208A0962024-07-25025 July 2024 57243-EN 57243 - Rssc Wire & Cable LLC, Dba Marmon - Part 21 Notification PLA-8117, 23rd Refueling Outage Owners Activity Report (PLA-8117)2024-07-23023 July 2024 23rd Refueling Outage Owners Activity Report (PLA-8117) ML24197A0982024-07-15015 July 2024 Request for Information for a Biennial Problem Identification and Resolution Inspection; Inspection Report 05000387/2024010 and 05000388/2024010 PLA-8126, Response to Request for Confirmation of Information Regarding Relief Request 1RR062024-05-29029 May 2024 Response to Request for Confirmation of Information Regarding Relief Request 1RR06 ML24127A2262024-05-29029 May 2024 Issuance of Amendment Nos. 288 and 272 Adoption of TSTF-563 PLA-8122, Annual Radiological Environmental Operating Report (PLA-8122)2024-05-28028 May 2024 Annual Radiological Environmental Operating Report (PLA-8122) PLA-8115, Relief Request IRR06 One Time Extension to the Fourth 10-Year Inservice Testing Program Interval (PLA-8115)2024-05-23023 May 2024 Relief Request IRR06 One Time Extension to the Fourth 10-Year Inservice Testing Program Interval (PLA-8115) PLA-8123, Main Steam Isolation Valve Leakage2024-05-23023 May 2024 Main Steam Isolation Valve Leakage IR 05000387/20240012024-05-13013 May 2024 Integrated Inspection Report 05000387/2024001 and 05000388/2024001 IR 05000387/20244042024-05-0707 May 2024 Information Request for the Cybersecurity Baseline Inspection, Notification to Perform Inspection 05000387/2024404 and 05000388/2024404 PLA-8101, Re 2023 Annual Report of Radiation Exposure2024-04-22022 April 2024 Re 2023 Annual Report of Radiation Exposure PLA-8094, Radioactive Effluent Release Report and Offsite Dose Calculation Manual PLA-80942024-04-22022 April 2024 Radioactive Effluent Release Report and Offsite Dose Calculation Manual PLA-8094 ML24082A1372024-04-22022 April 2024 Issuance of Amendment Nos. 287 and 271 Adoption of TSTF-568, Revision 2 and Associated Technical Specification Changes PLA-8095, 2023 Annual Radiological Environmental Operating Report (PLA-8095)2024-04-22022 April 2024 2023 Annual Radiological Environmental Operating Report (PLA-8095) PLA-8102, Annual Environmental Operating Report (Nonradiological) PLA-81022024-04-11011 April 2024 Annual Environmental Operating Report (Nonradiological) PLA-8102 PLA-8113, Response to Request for Additional Information Regarding Relief Request 4RR-11 (PLA-8113)2024-04-11011 April 2024 Response to Request for Additional Information Regarding Relief Request 4RR-11 (PLA-8113) PLA-8112, Relief Request 4RR-11 Relief from End of Interval Boundary Leakage Test PLA-81122024-04-0909 April 2024 Relief Request 4RR-11 Relief from End of Interval Boundary Leakage Test PLA-8112 PLA-8110, Submittal of Unit 1 Cycle 24 Core Operating License Report (Pla 8110)2024-04-0404 April 2024 Submittal of Unit 1 Cycle 24 Core Operating License Report (Pla 8110) PLA-8100, Property Insurance Program (PLA-8100)2024-04-0101 April 2024 Property Insurance Program (PLA-8100) ML24092A4022024-04-0101 April 2024 Annual Financial Report (PLA-8098) PLA-8109, Supplement to Request for Exemption from Certain Requirements of 10 CR 72.212 and 10 CFR 72.214 Resulting from Fuel Basket Design Control Compliance (PLA-8109)2024-03-21021 March 2024 Supplement to Request for Exemption from Certain Requirements of 10 CR 72.212 and 10 CFR 72.214 Resulting from Fuel Basket Design Control Compliance (PLA-8109) PLA-8107, Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 Resulting from Fuel Basket Design Control Compliance2024-03-19019 March 2024 Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 Resulting from Fuel Basket Design Control Compliance ML24067A2512024-03-19019 March 2024 Authorized Alternative to Requirements of the ASME Code ML24044A2532024-03-14014 March 2024 Associated Independent Spent Fuel Storage Installation – Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0077 (Security Notifications, Reports, and Recordkeeping & Suspicious Activity Reporting)) IR 05000387/20240112024-02-29029 February 2024 Commercial Grade Dedication Inspection Report 05000387/2024011 and 05000388/2024011 IR 05000387/20230062024-02-28028 February 2024 Annual Assessment Letter for Susquehanna Steam Electric Station, Units 1 and 2 (Reports 05000387/2023006 and 05000388/2023006) ML24039A1882024-02-27027 February 2024 Issuance of Amendment Nos. 286 and 270 Changes to Technical Specifications for Control Rods ML24037A3072024-02-22022 February 2024 Summary of Regulatory Audit in Support of Relief Request 5RR-02 PLA-8099, Proof of Financial Protection and Guarantee of Payment of Deferred Premiums (PLA-8099)2024-02-13013 February 2024 Proof of Financial Protection and Guarantee of Payment of Deferred Premiums (PLA-8099) IR 05000387/20230042024-02-0707 February 2024 Integrated Inspection Report 05000387/2023004 and 05000388/2023004 PLA-8096, Response to Request for Additional Information Regarding Proposed Relief Request for the Fifth 10-Year Inservice Test Program Interval2024-01-0404 January 2024 Response to Request for Additional Information Regarding Proposed Relief Request for the Fifth 10-Year Inservice Test Program Interval PLA-8077, Emergency Plan Revision 67 (PLA-8077)2023-12-27027 December 2023 Emergency Plan Revision 67 (PLA-8077) IR 05000387/20230102023-12-11011 December 2023 Fire Protection Team Inspection Report 05000387/2023010 and 05000388/2023010 PLA-8089, Submittal of Revision to Inservice Testing Program Plan2023-12-0505 December 2023 Submittal of Revision to Inservice Testing Program Plan PLA-8088, Request for Exemption from Enhanced Weapons, Firearms Background Checks and Security Event Notifications Implementation (PLA-8088)2023-12-0505 December 2023 Request for Exemption from Enhanced Weapons, Firearms Background Checks and Security Event Notifications Implementation (PLA-8088) PLA-8084, Application to Revise Technical Specifications to Adopt TSTF-568, Revise Applicability of BWR TS 3.6.2.5 and TS 3.6.3.22023-11-29029 November 2023 Application to Revise Technical Specifications to Adopt TSTF-568, Revise Applicability of BWR TS 3.6.2.5 and TS 3.6.3.2 ML23345A0682023-11-28028 November 2023 Technical Specification Bases, Manual PLA-8091, Response to Request for Additional Information Regarding Proposed Relief Request for the Fifth 10-Year Inseervice Inspection Interval (PLA-8091)2023-11-0808 November 2023 Response to Request for Additional Information Regarding Proposed Relief Request for the Fifth 10-Year Inseervice Inspection Interval (PLA-8091) IR 05000387/20230032023-11-0303 November 2023 Integrated Inspection Report 05000387/2023003 and 05000388/2023003 2024-09-06
[Table view] |
Text
TWO NORTH NINTH STREET, ALLENTOWN, PA. )8101 PHONEs l215) 821-5151 April 4, l975 s
~fr. James P. O'Reilly /pe (
Director, Office of Inspection and Enforcement ~4~g U. S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406 l ~ II SUSQUK10QiVA STEAM ELECTRIC STATION IViERDl REPORT ON HPiEhTIAL DEFICIENCY ER 100450 FILE 840-4 PLA-60
Dear Mr. O'Reilly:
In accordance Irith 10CFR50.55(e), attached are tIro copies of an interim report on a potential deficiency Irhich Lras discussed with your Mr. Heishman on March 6, l975.
Very truly yours, ss. W. Curtis Vice President-Engineering & Construction this ~6 of;/
S"orn to and subscribed before
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Notary Puolic jl vg Commission Expires: ~ r5< rP74 c-'~ih. Donald.F. Knuth ': .
Director Office of Inspection and Enforcement (0 cP U. S. Nuclear Regulatory'ommiss'on
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PENNSYLVANIA POWER 8 L I GH T COMPANY Rojgg+n+ ii88.4p
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DATE POTENTXAL DEFICIENCY.IDENTIFIED: hInrch 6, 1975 FACXLXTY: Su" quehanna Steam Electric Station, Units 1 and. 2
'OPXC OF XVa ZERXbf REPORT:
Additional loads have, been identified which should bemagnitude considered in the design of the suppression pool structures and equipment. The of these loads and their applicability to the SSES design bases have not been determined.
SCOPE OF INTERIM REPORT:
As required by 10CFR50.55(e) this interim report is submitted to describe a "
potential deficiency. which may have adverse affects on the Susquehanna Commission Steam Electric Station Units 1 and 2 (SSES). This report also advises the of the phenomena involved, provides a preliminary indication of implications, and describes corrective action underway.
IDENTXFICATXON OF POTENTXAL'DEFICIENCY:
The primary containment design bases and. load combinations described in the SSES PSAR Sections 5.2.2 and. C.2.6 do not explicitly include the following phenomena:
- 1) Suppression Pool Swell
- 2) Containment Vent Pipe Horizontal Loads from steam condensation
- 3) hiain Steam Safety/Relief Valve discharge pipe air clearing These phenomena were previously either considered not limiting or were considered.
not relevant to the SSES tlK XX pressure suppression containment. Two recent letters from General'Electric Company (NSSS vendor) to Bechtel Power Corporation (Architect Engineer) identify information that has been developed from the )lark IIX Pressure Suppression Test Facility (PSTF) and. which may be applicable to the SSES Containment. The phenomena and. their implications are described below.
DESCRIPTION OF Pier"NO.'~HA:
Two groups of phenomena have been identified. One group occurs as a result of the postulated. loss of coolant accident (XQCA) while tne other group occurs as a result of the actuation of main steam safety/relief valves. Xt should be realized. that the precise loads applicable to SSES have not been fixed at present; however, preliminary conservative estimates indicate that portions of the existing design may require modification.
LOCA M>en the LOCA occurs the air in the drywell is forced down the vent pipes into the suppression pool. The compressed air bubble formed at the end of each vent
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causes the water in the suppression pool to rise as a ligament when the bubble is formed and then expands. As thc bubble expands and rises in the pool, the ligament of water decreases until a point at which the bubble breaksStructures through the remaining layer forming a two phase "froth" of air and. water. and equipment that are above the suppression pool will be subjected to an impingement and/or drag load from this pool swell action. The type and magnitude of load. is a function of the height above the i'nitial water surface... These loads are not applied directly to the fission product barrier.
A conservative extrapolation of the data available from GE's Park XXI verification test program in the PSTF has been prepared .for preliminary determination of indi-structural loads. From this geliminary conservative evaluation, there are cations that some modification and/or relocati'on of equipment or structural members could. be required. Pipe seismic bracing, drywell to wetwell vacuum breakers, S/R Valve piping, suppression pool hydrogen recombiners and. the diaphragm slab are in the region affected.,by'ool swell.
Following the pool swell transien , there is a period of quasi steady sta e steam, flow through the vent pipes to the suppression pool. Information from testing performed at a foreign pressure suppression containment indicates that there are lateral loads which occur on the vertical vent pipes. Mhen applying a load which was determined from bounding the data available from the foreign tests, it was determined that additional bracing for the vents may oe required to accommodate the load.
S/R VALVE DISCHARGE The discha'rge piping of a safety/relief valve contains non-condensable containment atmosphere and. a column of water prior to actuation. Following safety relief valve actuation pressure builds up inside the piping as steam compresses the and forces the water from the pipe. The atmosphere follows the non-'ondensables water in the form of a high pressure bubble. Once in the pool, the bubble expands analogous to a spring and accelerates the surrounding water radially outward. The momentum of the water causes the bubble to overexpand and. the bubble pressure becomes negative. This negative pressure slows Gown and finally reverses the motion of the water, leading to the compression of the bubble, and, the sequence repeats itself until the bubble reaches the surface of the pool. The bubble oscillation causes pressure throughout the suppression pool resulting in oscillatory loads on pool boundaries and. submerged components.
For preliminary evaluation, clearing loads were established using the technique presented in N"-DO-10859. Tt is felt that the loads used were very conservative.
This preliminary investigation indicates that some modification to the safety relief valve discharge piping may be required.. This piping may be re-routed to minimize the magnitude of the pressure oscillations on the liner plate or it may be necessary to change the configuration of the end of the pipe to break up the high pressure air bubble.
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Page 3 When loads specifically anplicable to SSES due to these phenomena are defined a review of adequacy of the SSFS design features will be made.
STATUS OF THE PROJECT The construction of SSES is approximately 10$ complete. The suppression pool base slabs and. liner plates are complete and in place. The Unit 1 reactor support pedestal and its liner plate are complete up to the diaphragm'slab and 'are also in place. The Unit 1 suppression poo'ebar is complete and in place while the Unit 2 suppression pool rebar is being fabricated. Installation of structural steel and rebar for the Unit 1 diaphragm slab is nearly complete.
CORRECTIVE ACTION Ul'H)ERWAY An intensive effort by PP8cL, Bechtel and General Electric Co. to better identify the loads due to these phenomena is underway. The preliminary tasks of developing a plan for resolution of tnese issues and a schedule nave nearly ocen completed.
Work is proceeding on the development of mathematical models to determine dynamic load factors and to generate load. data. This will be augmented by a test program which is applicable to verification of the mathematical models deveLoped. The last task will be to determine the various loads for the SSES containment, to determine load combinations to be used, and to complete any required design changes.
A schedule for these activities will be submitted. to the liR~ C in the near future.
PP&L will keep the Commission informed of developments as a result of 'the work, underway.
Concrete pours and other critical activities involving the Containment wil be suspended. until necessary modifications in this area have been identified.. Prior to resuming construction of any affected portion of the Containment, thc proposed modifications will be reviewed with the HRC.