ML20084N195
| ML20084N195 | |
| Person / Time | |
|---|---|
| Site: | Three Mile Island  |
| Issue date: | 05/10/1984 |
| From: | Wilson R GENERAL PUBLIC UTILITIES CORP. |
| To: | Eisenhut D Office of Nuclear Reactor Regulation |
| References | |
| 5211-84-2114, RFW-0120, RFW-120, NUDOCS 8405160373 | |
| Download: ML20084N195 (20) | |
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GPU Nuclear Corporation
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- g gf 100 lnterpace Parkway Parsippany, New Jersey 07054-1149 (201)263-6500 TELEX 136-482 Wnter's Direct Dial Number:
May 10, 1984 5211-84-2114 l RFW-0120 Office of Nuclear Reactor Regulation Attn: D. G. Eisenhut, Director Division of Licensing U.S. Nuclear Regulatory Commission Washington, D. C. 20555
Dear Sir:
Three Mile Island Nuclear Station Unit 1 (TMI-1)
Operating License No. DPR 50 Docket No. 50-289 EFW System Environmental Qualification Your letter of M'ya 3,1984 requested that GPUN provide (a) information to assist the NRC staff to respond to a February 13, 1984 letter forwarded to the Commission by the Union of Concerned Scientists (UCS) and (b) responses to the NRC Staff's questions relative to the UCS 2.206 petition. Enclosure 1 entitled "EFW System -
Safety Grade" discusses our response to the three questions posed in UCS letter dated February 13, 1984. Enclosure 2 entitled "EFW System - Environmental Qualification" discusses EFW system and related equipment in a harsh environment which is qualified or exempted and responds to questions concerning specific EFW System components.
4 cerely,
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. F. Wi son Vice President-Technical Functions RFW/mt:0489g Sworn and subscribed to before me this /n N day of /)p,/ , 1984 Axc OL /Y. '-f &
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cc: J. Van Vliet /cuemmx.c R. Conte J. F. Stolz
Enclosure:
- 1) EFW System - Safety Grade g
- 2) EFW System - Environmental Qualification I
GPil Nuclear Corcoration is a subsidiary of General Public Utilities Corporation 8405160373 840510 '
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Enclosure 1 EFW System - Safety Grade Response to UCS Letter of February 13, 1984
- 1. Identify each specific aspect of the TMI-l EFW system which does not comply or is not known to comply with the regulations applicable to sys-l tems important to safety (including safety-grade, safety-related, and engineered safety feature systems).
I Response: The EFW System complies with federal regulations as they apply to l TMI-1. At the time of Licensing of TMI-l the Emergency Feedwater i System complied with all applicable regulatior,s and standards which l existed at the time for the EFW System. Since the accident at I
TMI-2, increased focus has been placed on the Emergency Feedwater System as described in IE Bulletin 79-05 (Series) and NUREG-0737.
The EFW System at TMI-l has also been the subject of extensive j review as part of the ASLB hearing and review before the ALAB. The
> ASLB found in its PID that the short-term actions recommended in the Commission's Order and Notice of Hearing to improve the time-liness and reliability of the TMI-l emergency feedwater system are necessary and sufficient to provide reasonable assurance that the facility can be operated safely in the interim until the system is made safety grade. Attached is a list of modifications which are planned for the Cycle 6 refueling which will make the EFW System safety grade. This list was presented to the Staff in our meeting in Bethesda on April 28, 1984.
- 2. For each deficiency or potential deficiency identified in response to item 1 above, explain whether and why GPUN believes that TMI-l can be operated without undue risk to public health and safety before correction of the deficiency or potential deficiency.
Response: There are no deficiencies in the EFW System in complying with regulations as they apply to TMI-1. Nevertheless, GPUN has com-mitted to upgrade the EFW System to safety grade. Below is a list of modifications planned for Cycle 6 and compensating measures to be taken until these modifications are complete. Therefore, GPUN believes that TMI-l can be operated without undue risk to public health and safety as presently configured.
l Long Term Items Measures
- 1) Redundant Safety Grade The arrangement at restart of the EFV-30A/B control EFW Control & Block valves is not single failure proof but has the Valves valve fail open on loss of instrument air and loss of control signal. Additionally, the EFW control L _ _ _ _ _ . _ _ _ . _ _ ._
valves are equipped with a handwheel which permits manual operator action to establish flow to the intact steam generator. When there is an initia-tion of the EFW system, an auxiliary operator will be stationed at the control valve. (See TMI-l Abnormal Transient Procedure 1210-10.) The auxi-liary operator will establish communications with the control room and will control the valves if EFW flow cannot be established from the control room.
The Appeal Board found itself "... satisfied with the plant procedures for manual control of the EFW flow control valves." ALAB-729, 17 NRC 814, 833 (1983). The EFV-30s will be environmentally quali-fied under 10CFR50.49 by restart.
- 2) Safety Grade Initiation This pending modification provides further on 4 PSIG Containment enhancement of the system in the event of a steam Isolation line/feedwater line break. Currently, action is manually initiated by the operator. Dependence on the operator will not result in core uncovery.
- 3) Safety Grade Hi OTSG Procedural guidance (ATP 1210-1) currently directs Level (MFW Isolation) the operator to isolate main feedwater based on and Low Level (EFW high OTSG level. Also procedural guidance (ATP Initiation) 1210-4) directs the operator to manually initiate EFW on low OTSG level. OTSG level is safety grade.
- 4) Safety Grade MSLRDS The Main Steam Line Rupture Detection System (MSLRDS) signals to the EFW control valves, EF-V30A/B, have been deleted to preclude the pos-sibility of unnecessary isolation of emergency feedwater under single failure conditions. In addition, a cavitating venturi installed for each EFW line will limit flow to a ruptured steam generator to minimize the potential of containment overpressurization (or steam generator overfill condition), and will also ensure sufficient EFW flow to the intact steam generator. The MSLRDS is considered to be adequate from a single failure standpoint--that is, a single active failure (such as a pressure switch, solenoid, control relay, 125V DC power source) will not prevent isolation of feedwater. Additionally, a single active failure will not result in inadvertent isolation of feed-water. The MSLRDS is seismic Class I inside containment. Following a main steam line break in the reactor building, the system will function to-isolate feedwater from the affected steam generator-since qualified pressure switches (for MSLRD) are to be installed in' June, 1984 and will be suitable
1 for the accident environment. While electrical separation between the redundant circuits is not L maintained outside containment (since a few of them i
run in the same trays / conduits), electrical separa-tion outside containment is not required for a main steam line break inside containment. The MSLRDS, therefore, is adequate for operation until the safety grade modification is installed.
- 5) Safety Grade Lo Lo Level By letter dated February 4, 1983 (83-040) GPUN Alarm in Control Room provided a failure modes analysis for the for each CST existing control grade instrument. Only in the event of a sensing line crimp (due to the trans-mitter falling) would the transmitter continue to read a static level. However the operator would note that no drawdown is indicated and investigate the problem. It is not credible to assume that each transmitter for each CST would fail in this manner. Therefore, at least one transmitter is expected to be available.
- 6) Safety Grade Power to Although TMI-l does not have a second isolation C0-Villa /B and upgrade. valve between SI/SIII piping to the condenser hot.
Cable routing for well for each line, the condensate storage systen:
C0-V14A&B is single failure proof. There are two condansate storage tanks (CST) and Technical Specifications water inventory in either tank.is sufficient for safe shutdown. The common cross connect between the two condensate pipes (containing C0-V14A/B) has two isolation valves (C0-Villa /B) and closure of either valve (C0-Villa /B) will ensure integrity of one CST inventory if one of the C0-V14A/B cannot be closed.
' All of the valves involved (C0-V14A/B & CO-Villa /B)_
.are Seismic I and by the.end of Cycle-6 refueling g outage their' cable' routing (C0-V14A/B'and
'C0-V111A/B) and power supplies.(C0-Villa /B) will-also be Seismic 1. In the interim, manual operator-action will ensure proper operation following a-
-seismic event.
.The TMI-l Emergency Procedure for Earthquake (1202-30) and relevant Alarm Response Procedures have been revised to instruct the~ operator to isolate the damaged Condensate Storage. tank from the EFW system by closing valves CO-V14A/B and ,
'C0-V111A/B when, tank level has reached the Tech.
< Spec; limit following EFW actuation,-'and/or fol-lowing any recognizable seismic: event.(a seismic-
- instrumentation alarm,is7available in the control room).
(-
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= - l 2
l e _ 7) Over Speed Trip Alarm This indication will provide additional diagnostic in the CR For Turbine. information in the control room as to why this EFW EFW Pump pump was unavailable. No specific regulatory requirement addresses this feature.
- 8) Safety Grade Auto Currently the operator uses safety grade OTSG Control Independent of level independent of ICS to manually control ICS for OTSG Level EFW and hence level in the OTSG. This modification will enhance the operation of the EFW system.
The relationship between the EFW system and the ICS was considered extensively in the TMI-l Restart proceeding. Pursuant to Short-term action 1(b) of the Commission's August 9, 1979 Order and Notice of Hearing in_that proceeding, Licensee has imple-mented automatic initiation of the EFW pumps independent of the ICS and, further, has provided
< separate manual EFW flow control capability in the control room, which will allow the operators to manually control EFW flow to the steam generators in the event of an ICS malfunction. The Licensing Board examined this issue and required no further modifications, finding that the actions taken provided a significant improvement in safety.
LBP-81-59, 14 NRC 1211, 1285-86 (Paragraph 802),
1362 (Paragraph 1031) (1981). The Appeal Board also evaluated the matter and considered "...the concerns regarding dependence on the ICS for con-
-trol of emergency feedwater to be resolved."
ALAB-729, 17 NRC 814, 833-34 (1983).
- 3. For each deficiency or potential deficiency which GPUN believes need not-be' corrected before the first-refueling outage after restart, explain why that deficiency ever needs to be corrected._In other words, if GPUN believes that the plant can be operated without undue risk to public health and safety until the first refueling, why would modifications be needed to assure public health and safety after the.first refueling?
Response
The heart of the UCS complaint'is not with the improvements yet to be made to' the TMI-l EFW system, but with the schedule for implementing those modifica-tions. It' appears to.be the UCS position here, as it was in the TMI-l Restart proceeding, that whenever.a safety improvement is endorsed as worthwhile, the plant by definition is not safe to operate until the improvement is imple-mented. In short, UCS rejects the concept, endorsed by the NRC and reviewing
- courts, that.backfitting safety improvements.to operating plants. involves the exercise of judgment and may be accomplished in a phased manner over time.
The Comission's backfit regulation,10 CFR Subchapter 50,109(a), provides that "(t)he Comission may ... require the backfitting of a f acility if it finds that such action will provide substantial, additional protection which is required for the public health and safety or the common defense and secu-rity." In promulgating that regulation, the Commission stated that: "the rapid changes in technology in the field of atomic energy result in the con-tinual development of new or improved features designed to improve the safety of production and utilization facilities." 35 Fed. Reg. 5317 (1970). Taking steps to improve safety does not mean, however, that a facility is unsafe without the improvements. In applying the backfit rule, the Director pre-viously had held that a decision to retrofit an existing facility does not necessarily imply that it is unsafe, but rather that substantial benefits to the public health and safety can be attained. In the Matter of Petition Requesting Seismic Reanalysis, 00-80-1, 11 NRC 153, 166 (1980).
The UCS concept of the appropriate standard for deciding whether and when to require modifications at operating plants was re,jected by both the Licensing and Appeal Boards in the TMI-l Restart proceeding. ALAB-729, 17 NRC 814, 827-28 (1983)
For the modifications listed in Attachment 1 of this enclosure (attached) compensating measures exist as discussed above. This will increase the reli-ability of the system which has already been determined to be sufficient for restart. That time period of one cycle is the shortest reasonable time period for modification of this complexity. Areas where compensating activities apply for the EFW system include principally seismic events, main steam line break and main feedwater line break. The probability of these events occurring in the given cycle is low for the magnitudes in the design basis accidents based on review of historical data and piping stress as indicated in our response of February 24, March 26 and April 26, 1984. In conclusion GPUN strongly believes (coincident with findings by NRC staff ASLB and ALAB) that the Emergency Feedwater System as configured at restart can be operated without undue risk to public health and safety and can be operated safely until the first refueling after restart.
U _. m
Enclosure 1 Attachment 1 EFW LONG TERM UPGRADE MODIFICATIONS MECHANICAL / STRUCTURAL.
e ADD REDUNDANT SAFETY GRADE EFW CONTROL AND BLOCK VALVES h
EFW HEAT SINK PROTECTION SYSTEM e PROVIDE SAFETY GRADE EFW INITIATION ON 4 PSIG CONTAINMENT ISOLATION SIGNAL e PROVIDE SAFETY GRADE OTSG LEVEL INSTRUMENTATION AND SIGNALS FOR MFW OTSG HIGH WATER LEVEL ISOLATION AND OTSG LOW WATER LEVEL INITIATION OF THE EFW SYSTEM e PROVIDE A SAFETY GRADE AUTOMATIC CONTROL SYSTEM INDEPENDENT OF
.THE ICS THAT PERMITS THE EFW SYSTEM TO CONTROL OTSG LEVEL WITHOUT INTERACTION WITH THE MFW SYSTEM e PROVIDE SAFETY GRADE MAIN STEAM RUPTURE DETECTION AND MFW ISOLATION SYSTEMS e ADD SAFETY GRADE LEVEL INDICATION AND LOW-LOW LEVEL ALARM IN THE CONTROL ROOM FOR EACH CONDENSATE STORAGE TANK EFW LONG TERM EP&I MODIFICATIONS e PROVIDE A SAFETY GRADE POWER SUPPLY TO VALVES C0-ViiiA/B AND UPGRADE THE CABLE ROUTING FOR POWER SUPPLY TO VALVES CO-V14A/B TO SEISMIC CLASS I CRITERIA 1
e PROVIDE AN OVERSPEED TRIP ALARM IN THE MAIN CONTROL ROOM FOR THE TURBINE DRIVEN EFW PUMP (EF-P-1) i
Enclosure 2 i
EFW System - Environmental Qualification In Attachment 2 to your letter of May 13, 1984 you requested additional information related to the Environmental Qualification of the EFW system to assist you in responding to the UCS 2.206 petition of January 20, 1984.
Attachment 1 to enclosure 2 provides in tabular form a list of EFW and related equipment located in a harsh environment. A number of these components have been previously identified as not requiring qualification and are summarily explained. The additional items identified were audited during your visit on May 7 and 8 to GPUN corporate offices. Documentation concerning these addi-tional items were reviewed and comments were discussed.
Attachment 2 to enclosure 2 provide the basis for exempting the EFW and related system components in a harsh environment noted in Attachment 1.
Attachment 3 to this enclosure provides responses to questions asked about certain indications related to the EFW System in a harsh environment.
Enclosure 2 Attachment 1 ,
EFW ELECTRICAL EQUIPMENT LOCATED IN A HARSH ENVIRONMENT INCLUDING ALL QUALIFIED EQUIPMENT TER Equipment Manufacturer Model Tag No(s). Item No. Qualification Status Motorized Valve Limitorque SMB-0 EF-V2A&B ll Qualified based upon Limitorque Reports B0058 Actuators and B0027.
Motorized Valve Limitorque SMB-000 EF-VIA&B 15 Qualified based upon Limitorque Reports B0058 and B0027.
Pump Motors Westinghouse HP 450 EF-P2A&B 51 Qualified based upon Westinghouse Report WCAP 7829 (Written vendor confirmation in process),
GPUN calculation 110lx-5350-020 for the motor bearings, and TMI-l Procedure 1420-Y-15 for splices.
Cable Instru- Continental Silicon 107 Qualified based upon GPUN calculation 110lX-ment Wire & Cable Rubber 5350-70 and Anaconda letter of 2/15/84. ,
Co. Insulation '
Cable, Power Kerite 106 Qualified based upon FRC reports. Submergence
& Control qualification verification ongoing based upon Kerite generic tests described in Kerite letter I of 5/4/84. l Diodes Square D JTXIN6071A Replaced No longer required. Diodes are used as suppres-sion devices across ASCO solenoid valve coils.
No ASCOs are used.
Terminal Block States NT 110 Qualified based upon various tests and data shown on SCEW sheet.
Flow Trans- Foxboro NE 130M FT-791, 799, None Qualified based upon Wyle Report 45592-4.
mitters 782, 788 E/P Converters Bailey RP-1211C SP-V5A&B 60 Replaced by I/P converters Conoflow model GT25CA1826. Qualification will be based upon Conoflow reports 3021 and 3419.
_. . . _ _ _ . ._. =. _ _ _ .. ,
' Equipment Manufacturer Model Tag No(s). Item No. -Qualification Status ,
Limit Switches NAMC0 D2400X2 LSA/MSV06 66 Associated with the turbi~ne drive EFP which does LSB/MSV-6 not require qualification. No electrical inter-connection to a functional system.
Limit Switches NAMC0 D1200G2 LSA/MSV-13A&B 67 Associated with the turbine drive EFP which does' LSB/MSV-13A&B not require qualification. No electrical inter-connection to a functional system.
. Limit. Switches Fisher LS/EFV-30A&B None These switches are electrically disconnected.
, Solenoid. Valves ASCO LB8201C94 SV3/EF-V-30 26 These solenoid valves are no longer installed A&B in the plant. No ASCOs are used in equipment 2
SV4/EF-V-30A&B requiring' qualification.
Solenoid Valves 'ASCO 8300C68G SVl/EF-V-30 28 These solenoid valves are no longer installed A&B in the plant. - No ASCOs are used in equipnent -
SV2/EF-V-30A&B requiring qualification.
- Solenoid : Valves ASCO LB83146 SV/EF-V-8A, 31 These solenoid valves are electrically discon-
-B&C nected and locked open with a collar.
D/P Switches Barton 277A FI-S-77, 78 77 These switches associated with EF-V-8 have been
& 79 electrically disconnected.
' Cable Anaconda FREP/CPE None Qualified based upon Anaconda Report 80282 FRC insulation Report F-C 4836-2 and Anaconda letter of 5/4/84.
. Cable - ! Boston Insu- None Qualified based upon BIW Report B 915 (written -
lation Wire vendor confirmation in process).
- x' Motorized Valve Limitorque SMB-1 MSV-2A/B None Qualified based upon Limitorque Reports B0058 Actuator and B0027.
~
Equipnent Manufacturer Model Tag No.(s) TER Item No. Qualification Status C0V-14A/B Exempted per attachment 2 COV-lllA/B Exempted per attachment.2 ASV-4 Exempted per attachment 2 EFP-1 Exempted per attachment 2 EFV-4&5 ' Exempted per attachment 2 MSV-4A/B Exempted per attachment 2 MSV-6 Exempted per attachment 2 MSV-1A,B,C,0 Exempted per attachment 2 MSV-10A/B Exempted per attachment 2 MSV-13A/B Exempted per attachment 2 PT 65, 71 & 75 Exempted per attachment 2 TE-230 Exempted per attachment 2 EFV-15A/B Exempted per attachment 2 ST-8 Exempted per attachment 2 MSV-8A/B Exempted per attachment 2 I
I Enclosure 2 Attachment 2 Emergency Feedwater and Related Equipment in a Harsh Environment To Be Exempted from Qualification Under 10CFR50.49
- 1. C0V-14A/B (Condenser Hotwell/ CST cross connect) have been exempted from the master list of equipment within the scope of the EQ program based on the following [COV-14A/B are motor operated valves which are normally open and which have indication in the Control Room.]:
o Should C0V-14A/B fail closed, there would be no effect on EFW delivery.
o Should COV-14A&B remain open following a High Energy Line Break (HELB) in the Intermediate Building, delivery of condensate to the EFW pumps is ensured based on the fact that COV-12 (for COV-14A);
C0V-7; COV-8; and COV-13 (for C0V-4B) can be closed to maintain condensate storage tank inventory (ATP 1210-10).
- a. C0V-12 (this a normally closed, motor operated valve with a IE power supply) is located in the non-harsh environment of the Turbine Bldg. (If the valve fails open it can be manually closed locally.)
- b. C0V-13 or COV-8 (COV-13 is motor operated valve powered from a non-lE power source; COV-8 is an electro-pneumatic level control valve with a IE DC power supply. Flow from the CST to the con-denser would cause these valves to go closed on high hotwell level) have handwheels for local manual closure and are located in the non-harsh environment of the Turbine Bldg.
o No electrical failure to C0V-14A or B due to harsh environmental conditions would cause degradation of the lE power supply system.
o' There is no electrical interconnection between COV-_14A or B and any other required system function.
o Operator action is based on CST level and is not relied upon by operators.
- 2. COV-lllA/B (CST Cross Connect) have been exempted from the master list of equipment within the scope of the EQ program based on the following.
[COV-lllA&B are motor operated valves which are normally open and powered from a non-1E power source and which have indication in the Control Room.]:
-o These valves are-not required to change position following a HELB in the Intermediate Bldg. (Closed for a seismic event.)
o Should either or both COV-lllA or 8 close due to a failure, EFW delivery is not affected.
o Also, no electrical failure due to the environmental conditions would result in the valve failure in the closed position. ,
o No electrical failure to COV-lllA and B due to harsh environmental conditions would cause degradation to the lE power supply system.
o There is no electrical interconnection between C0V-lllA and B and any other required system function.
o Valve position is not necessary to mitigate the event.
!3. ASV-4 (Aux Steam Supply Isolation) has been exempted from the master list of equipment within the scope of the EQ program based on the following.
[The ASV-4 valve is a normally closed, motor operated valve supplied with a non-lE power supply and with indication in the Control Room.]:
o Under LOCA and MSLB sufficient flow is provided to the OTSGs by a single motor driven EFW pump. (See GPUN letter dated 3/22/83). The steam driven EFW pump is not_ required for accidents which produce a harsh environment in the Intermediate Building. Failure of ASV-4 in the open position would have no deleterious effect upon the required EFW system function.
o No electrical failure to ASV-4 due to a harsh environmental con-ditions would cause degradation to the IE power supply system'.
o There is no electrical interconnection between ASV-4, and any other required system function.
o' _The operator takes no action on position indication.
- 4. . ;EFP-1 (Turbine Driven Pump) has been exempted from the master list of equipment within the scope of- the EQ Program based on the following:
o EFP-1 does not contain any necessary electrical components..
-5. EFV-4 & EFV-5 (River Water Supply) have been exempted from-the master list of; equipment within the scope of the EQ program based on the fol :
- lowing. [EF-V4 and 5.are locked closed, motor operated valves with lE 2 power supplies. 'The breakers _for._these valves are locked open'(operating procedure,1106-6).]:
o An emergency _ river water source is not required to mitigate the consequences of an HELB in the Intermediate Building.
- o. With the breakers locked open, there is no. position indication.-
- 6. MSV-4A/B (Atmespheric Dump) have been exempted from the master list of equipment within the scope of the EQ Program based on the following.
[MSV-4A and B are normally closed, pneumatically operated valves, sup-plied with non-lE power to an I/P converter and with indication in the Control Room.]:
o The valves are not required to mitigate the consequences of an HELB or LOCA for hot (licensed) shutdown.
o Exposure to harsh environmental conditions can not cause either MSV-4A and B valves to fail into the open position.
o MSV-4A and B contain electric limit switches. These limit switches provide indication in the main control room only. They have no interconnection to other system functions. Heat removal during HELB is assured using primary to secondary heat transfer which relies on instrumentation unaffected by the HELB. (See NAMC0 Limit Switch discussion in Enclosure 2, Attachment 3. of this letter.)
- 7. MSV-6 (Steam Supply to EFP-1) has been exempted from the master list of equipment within the scope of the EQ program based on the following:
o MSV-6 is a non-electric, pneumatic valve. The only electrical coraponents associated with this valve are limit switches. (See dis-cussion of NAMC0 Limit Switches, Enclosure 2, Attachment 3.of this letter.)
- 8. MSV-1A/B/C/D (Main Steam Isolation) have been exempted from the master list of equipment within the scope of the EQ Program based on the fol-lowing. [The MSV-1A, B, C and D valves provide main steam line isolation in the event of a steam line break and have indication in the Control Room:
o Should the MSV-1A thru D valves fail, the isolation function is achieved with the CV-1 thru 4 (turbine control valves) valves and/or SV-1 thru 4 (turbine stop valves) valves (located in a non-harsh environment).
o The MSV-1A thru D valves are stop-check valves providing an addi-tional assurance of main steam isolation.
o Between the MSV-1A thru D valves and-the turbine control valves the following major lines may need to be isolated in the-event of a steam line break to prevent blowdown of both OTSGs.
steam supply to the main feed pumps steam supply to the turbine gland seal system.
Both of the above lines are isolatable.via either local manual action (non harsh environment) or via remote control from the' control room.
. . . .. = , . . . . - - - - =
1
, o No electrical failure to the MSV-1A thru 0 valves due to harsh environmental conditions would cause degradation to the lE power l supply system.
- o There is no electrical interconnection between the MSV-1A thru D
! valve and any other required system function.
o Closure of the MSIV is based on overcooling, not valve position indication.
I
- 9. - MSV-10 A/B (Low pressure Steam Supply to EFP-1) have been exempted from the master list of equipment within the scope of the EQ Program based on the following. [MSV-10A & B are normally closed, motor operated valves, supplied with DC power and with indication in the Control Room.]:
) o These valves are not required to mitigate the consequences of a LOCA or HELB in the Intermediate Building.
I o No electrical failure to MSV-10A and B due to harsh environmental conditions would cause degradation to the lE power supply system.
o There is no electrical interconnection between MSV-10A and B and any other required system function.
o Operator action is based on overcooling considerations, not valve position indiciation.
I
- 10. MSV-13A/B (Steam Supply to EFP-1) have been exempted from the master list of equipment within the scope of-the EQ Program based on the following.
[MSV-13A and B are normally closed, solenoid operated pneumatic valves, supplied with DC power.]:
l 0 .These valves are not required to mitigate the consequences of an HELB or LOCA.
o Should the valves fail into the open position, the OTSGs could be isolated via closure of MSV-2A and 8_in conjunction with check valves
-MSV-9A and B.
o No electrical failure to MSV-13A and B due to harsh environmental
, conditions would cause degradation to the lE power supply system.
o There is no electrical interconnection between MSV-13A and B and any other required system function.
{ o _MSV-13A and B contain electric limit switches. These limit switches-provide indication'in the main control room only.--They have no. i interconnection to other system functions. Heat removal during HELB is assured using primary to secondary heat-transfer indication which is unaffected by the HELB. (See NAMC0 limit switch' discussion in Enclosure 2, Attachment'3 of thisEletter.)
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- 11. PT-65, 71 & 75 (EFW Pumps Discharge Pressure) have been exempted from the master list of equipment within the scope of the EQ program based on the following. [PT-65, 71 & 75 monitor EFW discharge pressure. The output of these pressure transmitters is displayed in the control room, and pro-vide the operator an input relative to pump operation.]:
o These pressure transmitters are referenced in procedures used to mitigate the consequences of an HELB or LOCA. However, other quali-fied instrumentation provided to the operator with data concerning the operation of the EFW pumps are used to verify EFW flow. These other instrumentation indications are steam generator pressure and level, emergency feedwater flow, primary coolant system temperature and pressure, and incore thermocouple temperature.
- 12. TE-230 (Bearing Cooling Water Temperature for the Turbine Driven EFP) has been exempted from the master list of equipment within the scope of the EQ Program based on the following:
o Since EFP-1 is not required to mitigate the consequences of an HELB in the Intermediate Building and LOCA, TE-230 need not be included into the EQ Program. Additionally, there is not direct indication of TE-230 in the control room, rather, TE-230 is input to the plant computer data logger.
o A failure of TE-230 has no effect on DC power.
- 13. EFV-15A/B (Bearing Cooling Water Regulating valves in Supply to Turbine Driven EFP) have been exempted from the master list of equipment within the scope of the EQ Program based on the following [no indication in the ControlRoom]:
o EFV-15A and B contain no electrical components, and are therefore, not included within the scope of the EQ program.
- 14. ST-8 (EFP-1 Pump Speed) has been exempted from the master-list of equipment within the scope of the EQ Program based on the following.
[ST-8 provides EFP-1 speed indication in the control room.]:
o ST-8 indication is not called for in plant procedures and hence, the operators do not rely upon this instrumentation to indicate pump operation. Other qualified instrumentation are utilized to verify pump operation including EFW flow, steam generator level, reactor coolant system pressure and temperature and core temperature.
o Failure of ST-8 has no effect on DC power.
- 15. MSV-8 A/B (Turbine Bypass Isolation) have been exempted from the master-
. list of equipment within the scope of the EQ Program based on the fol-lowing (MSV-8A/B are normally open. motor' operated valves supplied with lE l power with indication in the Control Room):
e o MSV-8A/B are not required to mitigate the consequences of an HELB in the Intermediate Building..
- o. Should MSV-8A/B~be needed to close to' prevent blowdown of both OTSG's the MSV-3A thru F (located in a non harsh environment) provide the isolation function.
o NoelectricalfailuretoMSV-8A/hduetoharshenvironmentalcondi-tions would cause degradation tc the lE power supply system.
1 o There is no electrical interconnection between MSV 8A/B and any other required system _ function.
o The operator does not rely on valve position for action.
For the above items, GPUN has determined that the function is not needed for HELB (with Loss of Offsite Power) with a single active failure.
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'% ; Enclosure 2 4
Attachment 3
' , " Justification For Ex'6mpting'Ceftain EFH System ElectricalEquipmelry
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A .. NAMC0 Limit Switches 3 ,
- 1. An ' analysis of the effects that failure of the limit' switches could have at 'otherJelectrical equipment important to safety, e.g., if the 4 switches arq used in an interlock circuit for other equipment.
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- Response
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These limit switchn fpr MS-V6 an'd MS-V13A&B provide indication 4
, only in the Main Control Room. They have,no interconnection to u other system functions. - s a
% 2.- A discussion pf the emergench procedures used by the Operator, whether the, operator is directed to rely,0n information from these 1
l!mit switchec for valve positions, how and'when the operator will .
manolJy_and "ilgMiately"s redt.ce overfeeding of the OTSGs in the event the Ifmit switches on MSV-6 fell, and why qualified EFW flow
< and 0TSC level preclude the operator from being' misled if the limit ~
! switches on MS-V13 A&B fail. -
s Response: The pri$cipt; procedures used by the Op'erator in a MSLB accident are:1 '
y, b ATPi ll10-3 ExceksiveCooling I 1Si' ITP l210-10 Abnormal Transient Rules Guides and Graph
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OP 1106-6' Engrgency Feedwater System. s
, s These procedures require verification that-3 EFW pumps start; EFW
> ; pump discharge pressure is 1010 psig, EFW fJow (if below OTSG' i leversetpoint); and EFV-30's control 0TSG level at setpoint.
1 The operator >would follow EFW throttling priteria (of ATP 1210-10 4
Sectionl'.5)'topFevkrtoverfilling.?!3? *
- A discussion on the desirability 'ef the' operator needing to' s' N 3.
"immedictely (manually)"' reduce overfeeding the GTSGs because of l ~ failure of'MS-V6 limit switches. ,and the desirability of relief
, , ' valves li'ftipg because of MS-V13A&8 limitqwitches failing.
Respo$se: Asdiscussed5$vetheoperatorisobser'vingtheEFWsystem throttling criter'ia-(not MS-V6/MS-V13 indication). As discussed' lin TMI-l restart report'overfeecing does~not become a problem.
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The pressure control valve (MS-V6) upstream of valves MS-V22A/B was j modified to limit its travel at 65% of stroke to protect the EFW pump i turbine from overpressurization due to the failure of any steam supply valves. This reduces the potential for opening of valves MS-V22A/B. In addition, these valves will not lift simply because the EFW turbine driven pump is started.
In our letter of 2/10/84 (5211-84-2038, Attachment II, Item I.G.1) we noted that under LOCA and MSLB. sufficient flow is provided to the OTSGs by a single motor driven EFW pump. The referenced analysis (in GPUN letter dated 3/22/83) was for LOCA and LOFW (Loss of Feed-water). This analysis has been supplemented by analysis reported in our letter of 12/9/83 (also for LOCA and LOFW). EFW flow require-ments for LOFW bound the flow requirements for MSLB.
B. Fisher Limit-Switches
- 1. Same as 1 above for limit switches.
Response: These limit switches are not connected electrically and therefore have no electrical interconnection to system functions.
- 2. A discussion of the emergency procedures used by the operator and whether these procedures direct the operator to rely on information from these limit switches.
Response: As discussed in A 2 above the procedures listed apply. No reliance is placed on position indication of the EFV-30 valves.
These limit switches are not electrically connected.
C. ASCO Solenoid Valves
- 1. An analysis of the effects that failure of the solenoid valves could have on other electrical equipment important to safety, e.g., disrup-
' tion of Class lE power on the circuit to which the solenoid valves are connected.
Response: The ASCO solenoid were once connected but now have had electrical leads lifted and instrument air has been disconnected. These modifications were performed as part of the deletion of the MSLRDS signal to the EF-V30's (no longer installed) and the removal of the EF-V8's control function.
- 2. For TER item No. 31, formally submit on the docket the justification for qualification exemption.
Response: As discussed in our response to C.1, these ASCO solenoid valves should be placed in NRC category III.B " Equipment not in the Scope of.the Review."
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D. Barton D/P Switches 1.- Address failure of these D/P switches similar to 1. above for the limit switches.
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. Response: The EF-V8 valves have had their electrical leads lifted, instrument air tagged out and a collar installed on the valve to physically prevent' change in position. There is no electrical interconnection of these switches with'ather system functions.
\ 2. .A discussion of the emergency procedsres used by'the operator and thether these procedures direct the operator to' rely on information from these D/P switches. ,
-'3* ' Response: Since these switches are not in operation there is no' reliance in procedures.on. the operation of thesa valves (EF-V8A/B/C,).
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- 3. . Formally submit on the docket' the justification. for qualif,ication exemption.
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Aesponse: These flow switches are for the EFW pump recirculatiori lines. The EF-V8 valves is now lockedsopen therefore these.~ switches are not ir.
f the scope ofg50.49 and should b'e placed in Category III.B.. As dis-
- cussed aboie there is no adverse interaction with, safety systems and no way to mislead th'e operator. ,
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