ML20041A118
| ML20041A118 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 02/11/1982 |
| From: | Daltroff S PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Stolz S Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8202190122 | |
| Download: ML20041A118 (13) | |
Text
__.
f PHILADELPHIA ELECTRIC COMPANY si e
23OI MARKET STREET A
P.O. BOX 8699 RECE'!ED g
PHILADELPHI A, PA.19101 g
FED 1~81982> T 42117I 841-5001 i awgagy
'9 SHIELDS L DALTROFF
.2 m'm %
G b
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February 11, 1982 Docket Nos. 50-277 50-278 Mr. John F.
Stolz, Chief Operating Reactors Branch #4 Division of Licensing U.
S.
Nuclear Regulatory Commission Washington, DC 20555
Dear Mr. Stolz:
Attached you will find additional information to support our September 3, 1981 response to your June 5, 1981 letter transmitting the Safety Evaluation for the Environmental Qualifications of Safety-Related Electrical Equipment at Peach Bottom Atomic Power Station Units 2 and 3.
This additional information 8s being provided as a result of our continuing discussions with your staff concerning the justification for continued operation of our Peach Bottom Atomic Power Station with respect to electrical equipment qualification.
If you have any questions or require additional information, please do not hesitate to contact us.
Very truly yours,
)
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./
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Attachment oA c
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i 8202190122 820211 PDR ADOCK 05000277 P
1
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Justification for Continued Operatien Peach Bottom APS, Units 2 and 3 This document supplements our September 3,1981 response to the Safety Evaluation for the Environmental Qualification of Safety-Related Electrical Equipent ai Peach Bottom Atanic. power Station, Units 2 and 3.
Table 1 of the ?;eptember 3, 1981 response identifies those equipment items with env'.ronmental qualification deficiencies; Table 1 is provided here as Attachment 1.
For clarity, the quali-fication deficiencies have been subdivided into the fol]owin6 o
categories:
1.
Deficiency resolved.
2.
Equipment perfoms its fitnction prior to exposure to the harsh environment.
3.
Subsequent failure of equipment or non-essential sub-components does not degrade other safety functions or mislead the operator.
1 Deficiency restricted to radiation.
4 5
Exemption from qualification up-grade.
6.
Other equipment deficiencies.
Category 1 The following portion of the equipment deficiencies identified in y
Table 1 have been resolved by analysis:
1.
PS-1!-0114 4A,B,C,D Units 2 and 3 4
2.
PS-10-120A,B,C,D,E,F,G Units 2 and 3 3
EPTB-003 Units 2 and 3 I4.
20B10,20B11,20B12,20B13 Units 2 and 3 Category 2 This category applies to that portion of the equipment identified
- 1 in Table l which has either a passive essential safety Ibnction or it perfoms its safety function prior to exposure to the harsh environment. The followin6 equipment has a passive essential safety Ibnction:
'1.
MO-10-13A,B,C,D Units 2 and 3 l
2.
MO-10-15 4A,B Units 2 and 3 1
MO-11-11A,B Unit 2 3
4 14 MO-10-31A,B Units 2 and 3 4
a h
5.
MO-14-26A,B Units 2 and 3 q
6.
MO-23-20 Units 2 and 3 7.
MO-23-25 Units 2 and 3
($
L}
The following equipment has an initial short duration active essential safety function:
j 1.
MO-10-25A,B Units 2,and 3 MO-11-12A,B Unit
-2 i
2.
4
.}
3.
SV-2671A,B,C,D,E,F,G Units 2 and 3 1
SV-2678A,B,C,D,E, F,G Units 2 and 3 4
5.
SV-2980 Units 2 and 3 y
o S
.t n
l,
None of the active essential valve achtators identified above would' be exposed to post-LOCA environmental effects within the time period
- z that their operation would be required since they are located out-l_
. side primary containment. In addition, the MO-10-25 actuators are 9
physically separated and on redundant loops; the same is true of the
-MO-14-12 actuators. Therefor.r, a HELB is not capable of causing a common mode environment during the. time period that the equipment would be required to operate.
In addition, the particular deficiency for all motor operated j.
valve actuators (MO) except MO-23-25 involves a subcomponent, the drive motor brakes. Our evaluation of this deficiency reveals that the actuator could perform its safety function despite failure of l.
this subcomponent (Attachment 2). The solenoid valves (SV) use the L
lJ force developed by process pressure to close, and coil failure would cause the valve to close thereby satisfying its safety function ~
j objective to isolate (Attachment 2).
l Category 3 I
i The following portion of the equipment identified in Table 1 is exposed to post-LOCA radiation, however, it is not exposed to pro-longed temperature changes:
l 1.
2A,2B,2C,2DP35 Units 2 and 3 I
2.
LS-23-92A,B Unit 2 3.
0A,OB,0CV20 Common plant 4.
N3692,N3693,N3772,N3773 i
N3783,N3784,N3884,N3885 Units 2 and 3 N3994,N3995 5.
DPS-00014,15 Units 2 and 3 LPS-20400-03 thru -20 The RHR pump motors 2A, 2B, 2C, and 2DP35 are qualified to 2.1 MR.
Although these motors would be expected to survive the postulated 101 day post-LOCA dose of 33 MR, an alternrte method of shutdown cooling via the main condensers could be used.
lI Level switches23-91A,B automatically transfers HPCI suction from the CST to the torus on high torus level. Alternate redundant torus level indication is available to the operator from LT-8027A i
and B.
In addition, these level transmitters provide the operator h
with a.high level alarm.
g h
OA, OB, and OCV20 are the Standby Gas Treatment fan drive motors.
Of the three motors which are available, only one is required, therefore, the system would be expected to be operational post-LOCA (Attachment 2).
. i-11' i _-_- _ _ ~ _ _ _ _ _ _ _
l ~ N3692 thru N3995 are local control switches for the HPCI and ECCS (Dnergency Core Cooling' System) area coolers. Each ECCS purrp room has redundant area coolers and control switches. The control switches perform an essential passive salety function and the organic materials are phenolic. In addition, these switches are a subcomponent of a metallic gasketed control station, and the energized subccanponents of the switch are protected by the control station enclosure. DPS-20400-03 thru 20 are control components for the HPCI and ECCS area coolers. Each ECCS pump room has redundant area coolers. Each cooler has a differential pressure switch (dps) which monitore l the fan operation. Their control function is to initiate the al-ternate cooler in the event that the preferred fan does not start. The application of these dps is a fail safe design, i.e., failure of the dps to actuate will cause both area coolers to operate j simultaneoucly. Category 4 I The following portion of the equipment identified in Table 1 has been exempted from a qualificatien up-grade based on our response to SER item 4.2: 1. MPL 23-1,2 Units 2 and 3 2. FT-23-82 Unite 2 and 3 3 PS-23-68A,B,C,D Units 2 and 3 4. PS-23-84-1 Units 2 and 3 5 PS-23-97A,B Units 2 and 3 ) Category 5 The following additional equipment with qualification deficiencies remains to be covered in this category: 20Dil,20D11A h 20B36,20B37,20B38~,20B39 h N210029A,N210025B L L Similar motor control centers (MCC) have been tested to temperature [ and pressure conditions which envelop the PBAPS requirements. This equipment would not be exposed to harsh environmental effects im-mediately after a LOCA, since the MCC's are located in secondary containment. In addition, the equipment enclosure is of dust tight j{ . construction; there are no vents, and compartment doors are gasketed. In the event of a HELB, RCIC can depressurize and provide the re- ,j quired water inventory make-up. Alternatively, ADS is available in combination with the low pressure ECCS systems and conventional i plant equipment such as the condensate pumps. This conventional )] plant eq'uipment is located in mild environment areas. ]- I W-- _.i-____._..__.__
1-4 In summary, we conclude that the continued operation of PBAPS does not constitute an undue risk to public health and safety due to the failure, for environmental causes, of safety related elec-trical equipment which would be required to mitigate the ecnsequences of a postulated accident. j ~. b i' h F e ( ) i ?- 4 k o
Table 1 CAT D Items Equipment Doncription Unit Manufacturer Componer.t No. Doriciency F;n Motor Common GECO OA,0B,0CV20 QT,T, P, H, R, A Valva Actuator 2 Limitorque MO-14-13A,B - QT,T, P,1!, R, A Valva Actuator 2 Limitorque MO-14-12A,B valva Actuator 2&3 Limitorque MO-10-25A,B (motor brake only) Valve Actuator 3 Limitorque MO-23-19 Valve Actuator 2&3 Limitorque MO-14-26A,B,10-154A.n Valve Actuator 243 Limitorque MO-10-13A,B,C D Valva Actuator 2 74 3 Limitorque MO-23-20,10-3SA,D Valve Actuator 2 te 3 Limitorque MO-23-25 (zotor only) Solenoid Valve 2&3 Atkomatic SV-2671A, D,C,D, E, F,5 - QT,T, P,11, R, A Solcnoid Valve 2 te 3 Atkomatic SV-2678A,B,C,D,E,F,G Solcnoid Valvo 2&3 Atkomatic SV-2980 Control Switch 2&3 GECO N3692, N3693, N3772 [ QT,P,1f,R,A N3773 Control Switch 2&3 GECO N3783, N3784, N3884, N3885 Control Switch 2&3 GECO N3994, N3995 l Level Switch 2&3 Robertshaw Is-23-91A,B R,A Prcncure Switch 2&3 Static-0-Ring PS-14-04hA,n,C,D R,A Pressure Switch 2&3 Static-0-Ring PS-10-120A,B,C,D, E, F,G,HP, R, A Prcesure Switch 2&3 narksdale PG-23-68A,B,C,D R,A Pruncure Switch 2&3 Static-0-Ring P3-23-84-1 R,A Static-O-Ring PS-23-97A,B R,A Dirrerential Common Dwyer DPS-00014,15 _ T,P,H,R,A Pressure Switch Dirrerential 2&3 Dwyer DPS-20400-03,04,05, Pressure Switch 06,07,08,0 9,10,11, 12,13,14,15,16,17, 18,19,20 Heater Common American Air Filter OA & BE65 R,T,QT, P,H, A Terminal Block 2&3 GECO EPTB-003 R,A 140 tor 2&3 GECO 2A,2B,20,2DP35 R,A - _ - _ = _ - _ _
r I f Table 1 (continued) i CAT B ltem ). i { Equipment Deceription Unit Manufacturer Component No. Deficiency Inad Center 2&3 ITE 20B10,11,12,13 R,T,qT,P,H,A R,T,QT,P,H,A II.ottr Control 2 Cutler Hammer 20D11A Center Motor Control 2&3 Cutler Hammer N210025A,D,20D36,37 Center ,Itot.cr Control 2&3 Cutler Homer 20D38,39,20D11 Center i Flow Trancmitter 2&3 GECO FT-23-82 qT,T,P,H,R,A HPCIPump/ Turbine 2&3 GECO MPL23-1,2 QT,T,P,H,R,A j Dif'f. Press. 2&3 Darton P3-10-121A,B,C,D T,A Ind. Switch e l
PBAPS Equipment Qualification Deficiency Evaluation
Purpose:
The SER on equipment qualification by the NRC for PBAPS Units 2 and 3 requires an evaluation of qualification deficiencies for equipment within the scope of the SER. Evaluation: Equipment - OA, OB, OCV2O Safety function - Drive standby gas treatment system motors, 101 days post-LOCA. Qualification deficiency - Lack of motor material traceability by manu-facturer. Deficiency evaluation - System design uses two 100f, capacity redundant filter trains with capability of using a third motor / fan for either train. Post LOCA accident environment can be considered mild except radi-ation dose fran SGTS filters. Based on BLP 21544 the 40 year nomal and post LOCA total integrated fan dose is 4.33x106 rads. Due to the physical layout, the third (standby motor) doce is expected to be less than 4.33x106 rads. Based on the above and in consideration of the typical materials used for motor construction, the likelihood of a motor failure due to the common mode post LOCA radiation exposure is in-significant. Equipment - MO-10-13A,B,C,D) 10-154A,B ) Group 1 14-llA,B ) MO-10-34A,B) 14-26A,B) Group 2 MO-10-25A,B) Group 3 14-12A,B) Safety function - Group 1 - passive essential Group 2 - normall,y closed and passive essential unless a surveillance test is in-progress coincident with a LOCA. Group 3 - essential active Qualification de ficiency - Lack of material traceability for drive motor brakes only. Deficiency evaluation - A review of operability requirements for the Group 1 and 2 valves reveals that they are normally l in their required position for safety system function and would not be required to change l position for response to a safety system init-iation signal. i u
r -2 The Group 3 valves are normally closed and would be required to open post LOCA; however, they are located outside primary containment, and based on a 3 hour time lag between inside and outside containment, they would experience no adverse temp, humidity during the period-in which their operation might be required. The 10-25A,B valves would be required to i open post-HELB however both valves would not be subjected to the inanediate effects of the same HELB and therefore the potential for common i mode failure of these valves does not exist. Furthermore, discussions with the manufacturer indicate that typical actuator drive motor stall torque is approximately 4 times greater than the static brake torque capability; there-fore, it can be concluded and demonstrated by i field experience that the motor can position the actuator regardless of brake failure. Equipment - MO-23-25 i Safety function - Passive essential - normally closed test return i to torus. Required for 15 min. post LOCA. i Qualification deficiency - Motor lead material not suitable for radiation i exposure. Deficiency evaluation - Valve is normally in its required position for safety system function and would not be required to change position for response to initiation signal. Post LOCA radiation exposure during period of interest would not be significant since water source is the condensate storage tank (see text of SER response to item 4.2). Equipment - SV 2671A,B,C,D,E,F,G SV 2678A,B,C,D,E,F,G l SV 2980 Safety function - Isolation of containment atmospheric control system post accident. Qualification deficiency - Material traceability and qualification docu-mentation. Deficiency evaluation - Valves are required for isolation only. They are nonna11y open with coils energized. A coil insulation failure will result in the valve changing to its required post accident position. 1 4 o _
T Ie. ' Equipment - 2A,2B,2C,2DP35 Safety function - Drive RHR pump motors for ECCS system performance and post accident shutdown cooling. ' Qualification deficiency - Motor test radiation level. Deficiency evaluation - In view of the 2.1 MR qualified test level the' design specification, the conservativism in the post LOCA radiation source term, and the i redundancy of the motors, the potential failure of this equipment to perform its safety hnetion due to common mode radiation failures is in-i significant. Equipment - LS-23-91A,B Safety function - Automatically transfers HPCI suction from CST to torus on high torus water icvel. Qualification deficiency - Radiation qualification test. Deficiency evaluation - The radiation dosage level is below the threshold value for most materials, the probability of a failure caused by radiation is insignificant. ) Equipment - N3692... Safety k netion - Maintain control circuit continuity post accident-time required is consistent with associated ECCS system performance requirements. Qualification deviciency - Test documentation radiation level too low. Deficiency evaluation - Device is used in a passive-essential mode post accident. Functional operability post-accident is not required, general construction is of phenolics and metallics. Based on passive essential requirements and consideration of non-metallic radiation characteristics, the ) potential failure of these switches due to i common mode radiation exposure post LOCA is j unlikely. j q Equipment - PS-14-0MA,B,C,D + Deficiency evaluation - Resolved via analysis {
i e L *.* l t j l j Equipment - PS-10-120A,B,C,D,E,F,G Qualification deficiency - No documentation for radiation tolerance of- } these S-0-R pressure switches. Resolved via analysis #126. I l Equipment - DPS-00014... Safety function - Maintain electrical continuity for area cooler i control circuit post accident, passive essential. l Qualification deficiency - No qualification documentation for this equip-l ment has been located. i ) Deficiency evaluation - These instruments sense differential pressure l across the area cooler fans (re E-197). 'Iheir l control function is to initiate the alternate fan in the event that the preferred fan does I not start. A failure of these switches would cause both area coolers to run simultaneously, i therefore, their failure would not adversely j affect the safety system performance. 1 Equipment - OAE,0BE65 j' Qualification deficiency - No qualification documentation for this equip-U ment has been located. T: d Safety fbnction - Heat SGTS process air prior to charcoal filtra-I tion post LOCA operation of SGTS. Deficiency evaluation - These heaters are required in order to maintain the process air relative humidity below the i condensable level. Condensation is undesirable because it would reduce charcoal filter efficiency; y however, the system is equipped with mechanical 4 de-misters and high efficiency particulate i filters which will remove.o3 micron particles which perform the same fbuction. The loss of ) efficiency due to charcoal filter wetting may j approach 90%. Based on the FSAR analysis, the resulting plant discharge is still within plant boundary radiation levels. Also, dis-cussions with the manufacturer indicate that the materials of construction are metallies and phenolics. Based on the preceding it is p I concluded that the present lack of documenta-tion constitutes minimal risk of failure due to post LOCA radiation exposure. 1 i s
. Equipment - EPTB-OO3-GE terminal block CR 151. Safety function - Maintain electrical continuity without ground or. point to point failure post accident. Qualification deficiency - Radiation qualification documentation. Deficiency evaluation - These teadnal blocks are used on instrumenta-tion ra ss. Most initiation instrumentation is required short term post accident, therefore radiation exposure is expected to be low. The generic material is suspected to be phenolic which is cabable of sustaining the postulated radiation levels without loss of function. Equipment - DPIS-lO-121A,B,C,D Safety function - These differential pressure switches open and close the min flow bypass valves associated with the RHR pumps. Qualification deficiency - Operating time by test is 6 hours vs. require-ment of 101 days. Radiation level is not-adequate. Deficiency evaluation - Safety function perfomance will be complete during initial ECCS system operation which is enveloped by the test conditions. Long term operability for shutdown cooling will not be required since the system is established in a steady state condition and pump / motor startup and shutdown will be infrequent. Equipment - 20BlO,ll,12,13 480 volt load centers Safety function - Provide 480 volt power to motor control centers. I Qualification deficiency - Environmental qualification documentation Deficiency evaluation - Vendor has provided a proposal to provide docu-mentation based on test infomation which is i available, therefore, this deficiency is not considered significant. Equipment - 20Dll, N210025A,B, 30B36,37,38,39 480 volt motor control centers. Safety function - Provide 480 volt power to various Class lE equipment. \\ i 1
4 (..s i Qualification deficiency - Environmental qualification doctanentation. Deficiency evaluation - Similar equipment has been tested for conditions which envelop PBAPS environmental requirements, therefore, safety system performance post accident can be expected. I i a p ( t .i e i t __}}