ML20154G927
| ML20154G927 | |
| Person / Time | |
|---|---|
| Site: | Maine Yankee |
| Issue date: | 12/31/1987 |
| From: | Whittier G Maine Yankee |
| To: | |
| References | |
| GDW-88-107, MN-88-54, NUDOCS 8805250162 | |
| Download: ML20154G927 (39) | |
Text
% 5 MaineYankee REttABLE ELEviRCTY FOR MA!NE $!NCE 1972 EDISON DRIVE . AUGUSTA. MAINE 04330 .(207) 622-4868 l10CFR50.59l May 6, 1988 HN-88-54 GDH-88-107 United States Nuclear Regulatory Commission Attention: Document Control Desk Hashington, D. C. 20555
References:
(a) License No. DPR-36 (Docket No. 50-309)
(b) HYAPCo Letter to USNRC dated March 11, 1981 (FHY-81-31)
Subject:
Annual Report of Facility Changes and Relief and Safety Valve <
Failures and Challenges Gentlemen:
In accordance with 10 CFR 50.59, attached is a report containing a brief description of the facility changes completed at the Maine Yankee Atomic Power Station during 1987.
In Reference (b), Maine Yankee committed to reporting any challenges and/or failures of PORV and pressurizer safety valves. During 1987 there were no such events.
Very truly yours, HAINE YANKEE
. t hAV G. D. Whittier, Manager Nuclear Engineering and Licensing GDW/sab Enclosure cc: Mr. Richard H. Hessman Mr. Hilliam T. Russell Mr. Patrick H. Sears Mr. Cornelius F. Holden 8805250162 871231 9 1 l DR ADOCK 0500 9898L-SDE
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SUMMARY
OF DESIGN CHANGES COMPLETED DURING 1987 EDCR 85-37 APPENDIX "J" LETDOHN SYSTEM MODIFICATIONS EDCR 85-38 ADDITIONAL PIPE RESTRAINTS FOR TK-19 DUMP LINE EDCR 85-47 HD-A-180 CONTROLLER INSTALLATION EDCR 85-51 IMPROVED EFH LUBE OIL COOLING EDCR 86-01 STEAM GENERATOR UPGRADE EDCR 86-02 REPLACEMENT OF STATION BATTERY N01 AND 3 EDCR 86-04 SERVICE HATER HEAT EXCHANGER UPGRADE EDCR 86-06 SERVICE BUILDING ALTERATIONS PHASE II EDCR 86-07 REVERSE ACTING CONTROLLER REPLACEMENT EDCR 86-08 CONTROL R00 POSITION DISPLAY SYSTEM EDCR 86-10 2ND PT FH HTR REPLACEMENT AND 6TH PT FH HTR TUBE BUNDLE EDCR 86-11 HATER TREATMENT CONDUCTIVITY TRIP AND DEMIN REGEN BACKFIT EDCR 86-13 NEW AUX STM PRESS TRANSMITTER LOCATION EDCR 86-14 TURBINE HATER INDUCTION PROTECTION EDCR 86-15 CONDENSATE HIGH CHLORIDE DILUTION HATER CONNECTION EDCR 86-19 APPENDIX "J" PRIMARY VENT SYSTEM HODIFICATION EDCR 86-20 APPENDIX "J" POST ACCIDENT PURGE SYSTO; HODIFICATION EDCR 86-24 CATHODIC PROTECTION SYSTEM FOR UNDERGROUND PIPING EDCR 86-25 EFH PUMP GLAND SEAL LEAK 0FF COLLECTION SYSTEM EDCR 86-28 HEATER DRAIN SYSTEM IMPROVEMENTS EDCR 86-31 HCB HUMAN FACTORS UPGRADE EDCR 86-32 INSTALL BATTERY CHARGER DISCONNECTS EDCR 86-33 HCB REPLACEMENT PANELS SECT A EDCR 86-34 HODIFICATIONS TO HSI-M-50 AND HSI-M-51 EDCR 86-35 HUMAN FACTORS LAYOUT FEEDHATER SECTION EDCR 86-36 REVISE P-2C RECIRC CONTROLS EDCR 86-37 DEDICATED ELECTRICAL SUPPLY TO S/G PLATFORMS EDCR 86-38 ICI CABLE RFPLACEMENT EDCR 86-41 DHST ALARM INSTRUMENT HODIFICATION EDCR 86-42 M0ISTURE PRESEPARATOR (SKIMMER) SYSTEM HODIFICATION
, EDCR 86-43 CONTAINMENT VALVE ACCESS l EDCR 86-44 FEEDHATER CHECK VALVE EDCR 86-45 REACTOR HEAD PERMANENT SHIELDING EDCR 86-46 REVISE SAFETY CLASS INSTRUMENT LAYOUT MCB SECT A EDCR 86-48 SEISHIC MARGIN PROGRAM EDCR 87-01 BENDIX ANALYZER RELOCATION PREPARATIONS EDCR 87-02 DR-1 VENT HODIFICATIONS 9b\\
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MaineYankee EDCR 85-37 APPENDIX "J" LETDOHN SYSTEM H0DIFICATIONS This change modified the reactor containment isolation boundary of the Reactor Coolant System (RCS) letdown system to allow the penetration boundary to be leak tested with gas in accordance with 10 CFR 50 Appendix J. Prior to this modification, the system was leak tested using a less accurate method.
This change to a safety class 2 system improved the integrity of the containment isolation boundary and permitted more accurate leak testing of the letdown system penetrations. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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i MaineYankee EDCR 85-38 ADDITIONAL PIPE RESTRAINTS FOR TK-19 DUMP LINE This modification involved the addition of three new pipe restraints on the high level dump line from the Heater Drain Receiver (TK-19) to the condenser.
These restraints were necessary to prevent excessive line movement during operation of the high level dump valve.
This modification was implemented to improve the operability and reliability of a non-nuclear safety system. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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Mainehnkee EDCR 85-47 HD-A-180 CONTROLLER INSTALLATION This. change involved the permanent installation of an electronic control system for the heater drain tank control valve (HD-A-180). The system was originally installed under a "yellow tag" as a temporary repair. Operating experience indicated that the new electronic control system demonstrated improved valve control over the original pneumatic control system.
This modification improved the control of a non-nuclear safety system. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 85-51 IMPROVED EFH LUBE OIL COOLING Tais change improved the cooling of the Emergency Feedwater (EFH) Pump Lube Oil by preventing short-circuiting of the minimum recirculation flow through the coolers and by replacing the existing coolers with new equipment si::ed to existing conditions.
This change increased the reliability of the EFH system by maintaining a lower temperature oil flow to the pump bearings when operating on minimum recirculation. This change did not increase the probability of occurr6nce or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 66 STEAM GENERATOR UPGRADE This design change involved the replacement of the existing steam generator dryer assemblies located in the upper section of the steam generators with new dryer vane banks. The new dryers allow for more complete moisture removal resulting in an increase in power output and reduce the wear and corrosion of the contact surface of the main steam lines and the high pressure turbine blading.
This change improves the performance and reliability of the plant. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different 4 type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-02 REPLACEMENT OF STATION BATTERY N0 1 AND 3 This design change involved the replacement of Station Battery Banks 1 and 3.
The banks were removed from their respective Battery rooms and replaced with new lead calcium batteries and battery racks.
This change improved the seismic design margin of station battery banks 1 and
- 3. This change did not increase the probability of occurrence o- the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as definsd in 10 CFR 50.59.
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MaineYankee EDCR 86-04 SERVICE HATER HEAT EXCHANGER UPGRADE This change involved the replacement of two of the four Primary Component and Secondary Component Heat Exchangers. The new units are titanium tubed units which are expected to provide significantly improved reliability. The new heat exchangers have been sized to ensure adequate cooling in the summer months while lessening the frequency of starting additional cooling water pumps.
This change improves the operation and reliability of the service water heat exchangers. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-06 SERVICE BUILDING ALTERATIONS PHASE II This change involved renovations to the locker rooms, chemistry labs and Radiation Control Checkpoint areas of the physical plant. The changes were made to allow us to improve our radiation controls practices and chemistry facilities.
This change improved the physical plant and facilitated improvements to radiation control practices. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did r.at present an unreviewed safety question as defined in 10 CFR 50.59.
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MaincYankee EDCR 86-07 REVERSE ACTING CONTROLLER REPLACEMENT This modification replaced reverse acting valve controllers with standard controllers on the Main Control Board (MCB). This resulted from Human Factors improvements identified during the Control Room Design Review. The following were replaced with standard controllers: Seal Water Supply Flow, Seal Water Pressure, Emergency Feedwater Flow, RHR Flow and Diffuser Vacuum. This change standardized controller operation on the Main Control Board (right movement is open, left movement is closed). The instrument loops that were modified were all Non-Nuclear-Safety related.
This change reduces the probability of operator error by standardizing the movement of controllers on the Main Control Board. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-08 CONTROL R00 POSITION DISPLAY SYSTEM This modification involved the replacement of the existing Control Rod Position Display System (Metrascope) with a micrcprocessor-based CEA Position Display System as a result of a human factors improvements evaluation.
The installation of the CEA Position Display System, which is non-nuclear-safety related, is a human factors improvement to the Main Control Board. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or=
a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-10 SECOND POINT FEEDHATER HEATER AND SIXTH POINT FEEDHATER HEATER TUBE BUNDLE REPLACEMENT Maine Yankee has maintained an ajgressive program to minimize pitting corrosion in the steam generators. In a continuing effort to reduce the ingress of copper contaminants in the feedwater train and thus in the steam generators, the Second Point Feedwater Heaters and the tube bundles of the Sixth Point Feedwater Heaters were replaced using copper free alloys. Thase changes additionally resulted in increases in thermal efficiency.
These modifications to non-nuclear-safety related components enhance steam generator tube integrity by further reducing the ingress of contaminants and thereby increasing plant safety. This change did not increase the probability of occurrence or the consequences of an accident or malfunctica of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-12 HATER TREATHENT CONDUCTIVITY TRIP AND DEHIN REGEN BACKFIT A new probe, transmitter and recorder were installed to improve monitoring of the mixed bed demineralizer effluent. This modification also included new trip valves which automatically discharge unsuitable water treatment effluent to the waste stream.
This modification improved the quality of the water supply for the regeneration :ycle of the Steam Generator Blowdown Demineralizer. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type tnan any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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r MaineYankee EDCR 86-13 NEH AUX STM PRESS TRANSMITTER LOCATION This change was installed to allow adequate isolation of the Condenser Air Ejector, EJ-1A, without consequent isolation of the Auxiliary Steam Pressure Transmitter PT-1101. The need for this change was a near plant trip which was the result of PT-1101 being inadvertently isolated during a valve line-up to isolate the Air Ejector for maintenance.
This modification to non-nuclear-safety relate J components reduces the probability of inadvertent plant trips. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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EDCR 86-14 TURBINE HATER INDUCTION PROTECTION This design change modified the operation of the level contro) valves for the Feedwater (FH) Heaters Under a Hi-Hi level condition. The control scheme was changed to automatically close the FH Heater cascading drains and fully open the emergency dump valves to divert flow to the condenser in the event of a Hi-Hi level signal.
These modifications to non-nuclear-safety related components were implemented to protect against turbine water induction. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-15 CONDENSATE HIGH CHLORIDE DILUTION HATER CONNECTION This change involved the installation of a 2" branch connection on the Condensate Cleanup Filter inlet header for a 21/2" fire hose adapter. The connection will be utilized to provide Fire Protection Water to the Condensate System for chloride dilution during initial plant warm-up operations.
Additional alternate sources available for connection to the new branch connection include the Clearwell and Clarifier.
This nodification to non-nuclear-safety related components is designed to reduce the demand on the treated water system during initial plant warm-up operations. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-19 APPENDIX "J" PRIMARY VENT SYSTEM H0DIFICATION This change consisted of modifications to the Primary Vent System Containment Isolation Boundary to improve testing in accordance with 10CFR50, Appendix J.
This involved the addition ci a :'" ball valve to be used as a test barrier and a 3/4" branch line to be u.cd es a test connection.
This change involved modifications to non-nuclear-safety related components which improved testing in accordance with NRC requirements. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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EDCR 86-20 1 APPENDIX "J" POST ACCIDENT PURGE SYSTEM HODIFICATION This change consisted of modifications to the Post Accident Purge System Containment Isolation Boundary to improve testing in accordaar.e with 10CFR50, Appendix J. This involved the addition of a 2" manual valve te be used as a test barrier and a 3/4" branch line to'be used as a test connection.
This modification improved local containment leakage rate testing in accordance with NRC requirements. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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EDCR 86-24 CATHODIC PROTECTION SYSTEM FOR UNDERGROUND PIPING This change upgraded the existing cathodic protection system such that underground yard piping is completely protected against external corrosion.
The original sacrificial anode system was proven to be of marginal benefit.
This modification to non-nuclear-safety related equipment improves the reliability of underground piping. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for_any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-25 EFH PUMP GLAND SEAL LEAK 0FF COLLECTION SYSTEM This change involved the rerouting of the Emergency Feedwater Pump (P-25A & C) gland leakoff lines from the Primary Auxiliary Building lower level sump to an existing condensate collection unit where it is pumped back to the Auxiliary Condensate Drain System. This change reduces the handling and processing of condensate which becomes contaminated waste in the sump and reduces plant makeup water requirements by approximately 720 gallons per day.
This modification which was non-nuclear-safety related improves the reliability of the plant. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-28 HEATER DRAIN SYSTEM IMPROVEMENTS This change replaced the existing 8" Heater Drain Tank level control valve (HD-A-180) with a 10" valvo of the same manufacture and model. The larger valve allows for better control of heater drain tank level.
This modification to non-nuclear-safety related equipment improves the control and operability of the heater drain tank. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of ,
an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-31 MCB HUMAN FACTORS UPGRADE As a result of the NUREG-0737 Control Room Human Factors Evalbation, several Human Engineering Discrepancies (HEDs) were identified. To correct these HEOs several existing components on the Main Steam and Reactor Control sections of the Hain Control Board were rearranged.
These human factors improvements are designed to reduce the potential for operator error. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as aefined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-32 INSTALL BATTERY CHARGER DISCONNECTS This design change installed circuit breakers between the safety class Battery Chargers (BC-1 thru 4) and their respective 125V DC Distribution Cabinets and the Inverters (IN-1 thru 4) and their respective 125V DC Distribution Cabinets.
Prior to this change all of the components were wired directly to each 125V DC Bus, making isolation for maintenance extremely difficult.
This modification to the 125V DC system enhances worker safety during maintenance. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-33 HCB REPLACEMENT PANELS SECT A As a result of the NUREG-0737 Control Room Human Factors Evaluation, several Human Engineering Discrepancies (HEDs) were identified. To correct these HEDs several existing components on the Main Steam and Reactor Control sections of the Main Control Board were rearranged. This change addressed the design of the plates and seismic mounting for these relocations.
These improvements to the Main Control Board components will enhance their ability to withstand a seismic design event. This change did not increase the probability of occurrence or the consequances of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-34 H0DIFICATIONS TO HSI-M-50 AND HSI-M-51 This design change installed torque bypass features for the Refueling Water Storage Tank to Charging Pump Suction Isolation Valves (HSI-H-50 & 51). A torque bypass feature is a limit switch contact wired in parallel with the torque switch that is closed for approximately the first 10% of valve travel in the desired direction. This feature allows the valves, if they become heavily seated, to either open or close on limit depending on the selected direction of travel. These two valves must operate one complete cycle under emergency conditions. They are designed to open on a Safety Injection Actuation Signal and close on a Recirculation Actuation Signal. Testing performed following installation verified that the design modification did not alter system operation.
This modification improved the design of these two isolation valves to perform their intended function. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-35 HUMAN FACTORS LAYOUT FEEDRATER SECTION This modification involved the relocation of instruments in the Feedwater portion of Section A of the Main Control Board to comply with Maine Yankee Human Factors criteria.
This change involving only non-nuclear-safety related components resulted in human factored improvements to the Main Control Board. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-36 REVISE P-2C RECIRC CONTROLS This modification implemented revisions in the steam driven feed pump (P-2C) recirculation control system to reduce inadvertent opening of the recirc valve (FH-A-342) which has been considered the cause of plant trips. The recirc valve actuator was reversed from an air-to-close to an air-to-open configuration and the controller output to the valve was modified with a circuit which blocks the air open signal at full power operation.
This modification to the steam driven feed pump (P-2C) recirc control system improves plant safety by reducing the potential for inadvertent opening of the recirc valve and also improves plant reliability. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-37 DEDICATED ELECTRICAL SUPPLY TO S/G PLATFORMS This change added 120V AC electrical outlets near the platforms located by the primary manway of the Steam Generators in each of the Containment building loops. The outlets are needed for tools required during normal maintenance and inspection of the Steam Generators.
This modification provides locally available 120V AC power for normal maintenance and inspection of the steam generators. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-38 ICI CABLE REPLACEMENT l
This modification involved the replacement of several In-Core-Instrument assemblies and cables with environmentally qualified assemblies. This is a continuation of work started under PDCR 10-80, EDCR 83-514 and EDCR 85-34.
This modification increases the probability of this equipment performing its intended function during accident conditions. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-41 DHST ALARM INSTRUMENT H0DIFICATION This design change provided a separate computer alarm from a level indicator on the Main Control Board for a low-low level in the Demineralized Hater Storage Tank (TK-21). The level alarm is independent from the Panalarm annunciators that actuate from the tank level switches. An oxisting spare nozzle on TK-21 was utilized to provide a mechanically independent connection for the level transmitter which provides the signal to the level indicator.
This modification provides an additional low-low level alarm for the DHST to permit any timely appropriate operator action. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-42 MOISTURE PRESEPARATOR (SKIMMER) SYSTEM HODIFICATION This ;hange consisted of removal of four existing orifices and installation of multiported orifices in each of the 16 lines from the HP Turbine exhaust to the Preseparator chamber of the High Pressure Turbine Maisture Preseparator System.
This modification improves the reliability and performance of the HP turbine moisture preseparator system. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-43 CONTAINHENT VALVE ACCESS This change involved the permanent installation of platforms, ladders and devices to improve the safe access to a number of valvr.s located in the Containment Building. Steel rungs were added to the supports of the Control Element Drive Mechanism Coolers for safer access to :he cooler vent and drain valves. Chain operators were installed on the High 'ressure Safety Injection Loop Stop Valves. Steel ladders were placed in the Containment annulus area to provide access to the Containment Spray Header Drain Valves. A portable steel rolling ladder was purchased and securely stored ir, the Containment Building to provide access to several valves.
This change improves safe access or control over certain valves in Containment. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86,-44 FEEDHATER CHECK VALVE This change involved installing the internals in the three existing Feedwater System check valves (FH-115, 215, 315) so that the valves will provide redundancy in the event that the existing check valves (FN-131, 231, 331) became inoperable and a reverse flow condition occurred.
This modification improves the reliability of the Feedwater System components. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-45 REACTOR HEAD PERMANENT SHIELDING This change provided a permanent installation of a support structure for lead
- shielding around the reactor head. The lead shielding is installed only during i
refueling. The support structure consists of a track system which is permanently mounted to the reactor head lifting rig columns. The installation
- was analyzed seismically and structurally.
This change is expected to reduce the duration for installing shielding around the reactor head and a concurrent reduction in radiation exposure for this task. This change did not increase the probability of occurrence or the
! consequences of an accident or malfunction of equipment important to safety
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previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-46 REVISE SAFETY CLASS INSTRUMENT LAYOUT MCB SECT A Based on a Human Factors Review of the Maine Yankee Main Control Board, this modification relocated class 1E feedwater instrumentation in Section A of the Main Control Board.
This change results in a human factors improvemnet to the Main Control Board.
This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaleated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 86-48 SEISMIC MARGIN PROGRAM This change addressed the structural seismic anchorage upgrade of several plant components. Safety related transformers X-507 and X-608 core and coil structures were reinforced. The Containment Spray Building HVAC Fans FN-44A &
B had additional anchorage installed. Masonry wall VE 21-1 in the Ventilation Equipment Area was structurally modified. And the Refueling Hater Storage Tank (TK-4) anchor chairs were modified.
This change increased the seismic design margin of safety related components at Maine Yankee. This change did not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 87-01 BENDIX ANALYZER RELOCATION PREPARATIONS This change addressed the installation of valves, reach rods and taps in preparation for the implementation of a design change to relocate the Bendix Hydrogen Analyzer in accordance with manufacturer's recommendations.
This modification will permit a timely relocation of the Bendix Hydrogen Analyzer. This change did not increase the probability of occurrence or the consequences of an accident or malfunction cf equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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MaineYankee EDCR 87-02 DR-1 VENT MODIFICATIONS This change resulted in the following modifications to the Gland Steam Vent system:
o A loop seal was.added on the E-9 drain loop seal overflow line to reduce air in leakage to the main condenser; o a drain was installed downstream of the EJ-3A & B discharge in the off-gas line to minimize moisture buildup; o the Gland Steam Exhausters (EJ-3A & B) discharge and casing drains were tied together with a new drain line which passes through a single loop seal. A gate valve was installed in the drain line for isolation in the event of a loss of the loop seal.
This modification improves the reliability of the Gland Steam Vent System.
This change did not increase.the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated, create the possibility of an accident or malfunction or a different type than any evaluated previously in the safety analysis or reduce the margin of safety as defined in the basis for any Technical Specification. The change did not present an unreviewed safety question as defined in 10 CFR 50.59.
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