ML20078F738
| ML20078F738 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 10/03/1983 |
| From: | Kemper J PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Schwencer A Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8310110132 | |
| Download: ML20078F738 (9) | |
Text
.
PHILADELPHIA ELECTRIC COMPANY 2301 MARKET STREET P.O. BOX 8699 1881 -1981 PHILADELPHIA. PA.19101 (215) 84 f.4 502 JOHN S. KEMPER VICE PR ESIDENT October 3, 1983
............o.....m Mr. A. Schwencer, Chief Licensing Branch No. 2 Division of licensing U. S. Nuclear Regulatory Camission Washington, D. C.
20555
Subject:
Limerick Generating Station, Units 1 and 2 Safety Evaluation Report Open Issue #19 Reclassification of Events
Reference:
Telecon, J. T. Robb and D. F. Ciarlone (PECO) to B. Hardin (NBC), September 20, 1983 File:
GOVT l-1 (hE)
Dear Mr. Schwencer:
The subject open item was discussed during the reference telecon.
In the discussion the NRC Reviewer restated the NRC position regarding the frequency classification of the generator load rejection with bypass failure event and of the turbine trip with bypass failure event. 'Ihe PECO Engineer then described the calculational procedure actually used to analyze the two transients in question.
At the conclusion of the telecon, it was agreed that PEOO would continue to impow the moderate-frequency-event safety criteria upon these two transients pending ccrupletion of the review of this generic question by the NRC staff. It was further agreed that PECO would document the information and positions conveyed by making the appropriate revisions to the IJJnerick FSAR.
Attached are draft revisions co FSAR Table 15.0-1, and FSAR Sections 15.2.2.1.2.2 and 15.2.3.1.2.2.
These draft FSAR revisions will be incorporated into the FSAR exactly as they appear on the attachments in the revision scheduled for tbvenber 1983.
Sincerely, 0310110132 831003 (7g g-PDR ADOCK 05000352 W
E PDR
\\
DEC/mjb 9/30/83-1 Copy to: See Attached Scrvice List
cc: Judge Lawrence Brenner (w/o enclosure)
Judge Richard F. Cole (w/o enclosure)
Judge Peter A. Morris (w/o enclosure)
Troy B. Conner, Jr., Esq.
(w/o enclosure)
Ann P. Hodgdon, Esq.
(w/o enclosure)
Mr. Frank R. Romano (w/o enclosure)
Mr. Robert L. Anthony (w/o enclosure)
Mr. Marvin I. Lewis (w/o enclosure)
Judith A. Dorsey, Esq.
(w/o enclosure)
Charles W. Elliott, Esq.
(w/o enclosure)
Jacqueline I. Ruttenberg (w/o enclosure)
Thomas Y. Au, Esq.
(w/o enclosure)
Mr. Thomas Gerusky (w/o enclosure)
Director, Pennsylvania Emergency Manadement Agency (w/o enclosure)
Mr. Steven P. Hershey (w/o enclosure)
Angus Love, Esq.
(w/o enclosure)
Mr. Joseph H. White, TII (w/o enclosure)
David Wersan, Esq.
(w/o enclosure)
Robert J. Sugarman, Esq.
(w/o enclosure)
Martha W. Bush, Esq.
(w/o enclosure)
Spence W. Perry, Esq.
(w/o enclosure)
Atomic Safety and Licersing Appeal Board (w/o enclosure)
Atomic Safety and Licensing Board Panel (w/o enclosure)
Docket and Service Section (w/o enclosure)
Jay M.
Gutierrez (w/o enclosure)
LGS FSAR TABLE 15. 0- 1 (Pace 1 of 3)
RESULTS SU4 MARY OF TRANSIENT EVENTS APPLICABLE 'IO BWRs i I
MAXIMUM l
CORE 1
AVERAGE DURA-MAXIMUM SURFACB NO. OF TION MAXIMUM MAXIMUM MAXIMUM STEAM HEAT VALVES OF PARA-NEUTRON DOME VESSEL LINE FLUX 1ST BIDW-GRAPH FIGURE FLUX PRESSURE PRESSURE PRESSURE 5 OF FREQUENCY BLOW-DOWN l
NQt,_
NO.
DENCRI PTION L NBR_
(psiel _
(psiq) jpsigl__ INITI AL_ &CPRC a a CATEGORYc : a DOWN 1se_cl i 15.1 DECREASE IN CORE COOLANT TEMPERATURE
[
15.1.1 15.1-1 Loss of Feedwater Heater, Automatic Flow Control 119.1 1024.0 1060.0 1014.0 113.5
<0.16(*2 a
0
- 0. 0 1
15.1.1 15.1-2 Loss of Feedwater Beater, 0.16 a
0 0.0 l
Manual Flow Control 127.7 1030.0 1069.0 1016.0 119.4:
15.1.2 15.1-3 Feedwater Controller Failure, Maximum Demand, 1275 Flow (3 3 156;3 1168 1194 1165 105.0i 0.06 a?
1'14 3
6 0 - l.+.u_
o,,
15.1.3 15.1-4 Pressure Regulator
~T a'-
W-
~3 &. --I-Failure - Open ~
<0. 0 6( *
- 104.3 1149.0 1165.0 1148.0 100.3, l
15.1.4 Inadvertent Opening of Safety or Relief Valve See Text D
15.1.6 Inadw rtent RHR Shutdote i
a Cooling Operation See Text g
i 15.2 INCREASE IN REACTOR PRESSURE 15.2.1 Pressure Regulator i
Failure - Closed See 15.2.2 and 15.2.3 (Bypass on) a 15.2.2 15.2-1 Generator Ioad Rejection, Trip Scram, Bypass, and bl 14
- 6. 0 l
RPT - On( 33 178.5 1169 1193 1164 101.2 0.03 a
i b
i 15.2.2 15.2-2 Generator Load Rejection, 14 12.7 l
Trip Scram. Bypass - Of f, 222.5 1200 1225.0 1196.0 106.2; 0.0b i
RPT - On( 33 15.2.3 15.2-3 Turbine Trip, Trip Scram, and RPT - On 163.3 1174.0 1196.0 1169.0 102.0
<0.16(48 a
14
- 5. 8 l
l Rev. 22, 07/83
f D
I l
T&BLE 15.0-1 (con t' d) 5 &IIS U.1, COBE l
DURA-A TEE &G E j NO. OF YION RAIIMUs SUBFACE YELTES OF RAIIBU5 BAIIEUM BAIIEUR ST E15 BEAT i
1ST
_BLOE-NEUTRON DO5E TESSEL LINE FLUI FREQUENCY BLOE-DOWN FL UI PRESSURE PRESSURE PRESSURE 5 OF PAB1-Libs _ JPsiSL__1D219)._192i91_-IMITZhk bCEEW SA1ZMB12 D913_1&sgl GRAPH FIGUEE EQ u 19e DZDGBIE119B 14 12.6 By pass - Off, RTP - On(3) 198.4 1198 1223.0 1195.0 104.5 0.06
.f g 15.2.3 15.2-4 Turbine Trip, Trip Scran, 190.9 1187.0 1220.0 1185.0 100.0
<0.06(*)
a 14 11.5 15.2.4 15.2-5 5 SIT Closure, Position Switch Scram 160.9 1172.0 1194.0 1168.0 101.9
<0.06(*)
a 14 10.8
^
15.2.5 15.2-6 Loss of Condenser Yacuun 104.3 1180.0 1194.0 1179.0 100.1
<0.06(*)
a 14
- 7. 5 15.2.6 15.2-7 Loss of nuriliary Power Transformer Connections 109.3 1173.0 1190.0 1169.0 100.0
<0.06(*)
,a,,
14, 11.6 15.2.6 15.2-8 Loss of All Grid
.s 15.2.7 15.2-9 Loss of 111 Feedwater Flov
_ 104.3 1144.0 1155.0 1144.0 100.0'
<0.06(*)
a 5
- 2. 2 ' - * -"
- 27
- - i 12 1 U*
Feedwater Line Break See Table 15.0-3, event 15.6.6 15.2.8 15.2.9 Failure of SHR Shutdown See Text Cooling 15.3 DECREASE IN RE ACTOR COOLANT SYSTES FLOW RATE 104.3 1021.0 1057.0 1011.0 100.0;
<0.06(*)
a 0
0.0 15.3.1 15.3-1 Trip of one Recirculation Pump Botor 104.3 1149.0 1100.0 1140.0 100.1
<0.06(*)
a 5
3.0 15.3.1 15.3-2 Trip of Both Becirculation Pump Hotors 15.3.2 Recirculation Flow Control a
Failure - Decreasing Flow See 15.3.1 104.3 1023.0 1057.0 1013.0 102.2
<0.16(*)
c 0
- 0. 0 1
15.3.3 15.3-3 Seizure of One Recirculation Pump c
15.3.4 Becirculating Pump Shaft See 15.3.3 Break i
B e v.
23, 06/83
LGS FSAR TABLE 15.0-1 (Cont' d)
(Page 3 of 3)
MAXIMUM CORE AVERAGE DURA-MAXIIEJM SURFACE NO. OF TION IRXIM IM MAXIMUM MAXIMUM STEAM HEAT VALVES OF PARA-NEUTRON DOME VESSEL LINE FLUX 1ST BIDW-i GRAPH FIGURE FLUX PRESSURE PRESSURE PRESSURE 5 OF FREQUE!CY BLOW-DOWN I
lgu NO.
DESCRI PTION 5 NBR_ _ Jgsht__ Jpsgl__ (psigl__ INITIAL _ ACPR(a s CATEGORY ( a a DOWN gect i 15.4 REACTIVITY AND POWER DISTRIBUTION ANOMALIES I
15.4.1.1 -
Rod Withdrawal Error (BWE) -
b f
Refueling See h xt 15.4.l.2 -
RWE - Startup See Text b
i b
15.4.2 RWE - At Power See Text 15.4.3 Control Rod Missperation See 15.4.1 and 15.4.2 b
15.4.4 15.4-6 Abnormal Startuo of Idle Recirculation Loop 454.9 981.0 996.0 977.0 150.8 (sa a
0 0.0 l
15.4.5 15.4-7 Recirculation Flow Control Failure - Increasing Flow 382.3 982.0 1001.0 928.0 145.1
<s3 a
0 0.0 l
15.4.7 Misplaced Bundle Accident See Text b
15.4.9 Rod Drop Accident See hxt c
15.5 INCREASE IN REACTOR g*
COOLANT INVENTORY 15.5.1 15.5-1 Inadvertent HPCI Pump Start 127.0 1023.0 1060.0 1013.0 107.7,
<0.16(*)
a 0
- 0. 0 l
15.5.3 BWR Transients See appropriate events in 15.1 and 15.2 I
(a3 a = Incidents of moderate frequency l
b = Inf requent incidents c = Limiting faults cm) aCPRs are based on initial CPR that would yield a MCPR of 1.06.
l (33 Results do not include adiustment factors and utilize EOC parameters (Ref erence 15.0-r,3 l
Estimated value, based on comparison with the most severe transient in the pressurization or l
(*)
nonpressurization category.
I These events are postulated to occur at low power and low flow conditions; a larger thermal margin I
(S) is maintained above the safety limit prior to the event occurrence. Therefore, the resulting MCPR l
l is well above 1.06.
I (G) %e emL o<e clen;{t<4
- m. I*<-le -(< ye y e<< dr fo < a.Iyris to ry.m es pend;~s tHe S i m.I as.le i t e n of
&;r y e n e<. t issa t as 11:reassed in see+u.y tr 2.2.I.T.L an<
t r. 2.2.1 2. z.
(
15.2.1.5 Radioloaical Consequences Because this transient does not result in any fuel failures, or any release of primary coolant to either the secondary containment or to the environment, there are no radiological consequences associated with this transient.
15.2.2 GENERATOR LOAD REJECTION 15.2.2.1 Identification of Causes and Frequency Classification 15.2.2.1.1 Identification of Causes Fast closure of the TCVs is initiated whenever electrical grid disturbances occur that result in significant loss of electrical load on the generator.
The TCVs,are required to close as rapidly as possible to prevent excessive overspeed of the turbine-generator (T-G).
Closure of the main turbine control valves will cause a sudden reduction in steam flow that results in an increase in system pressure and a reactor shutdown.
15.2.2.1.2 Frequency Classification 15.2.2.1.2.1 Generator Load Rejection This transient is categorized as an incident of moderate frequency.
15.2.2.1.2.2 Generator Load Rejection with Bypass Failure
[
' This tranciant in catonnri7ad am an infrannant incident with a
.h. _. N TB Frecuency Basis:
Thorough searches cf domestic plant operating recoros nave revealed three instances of bypass failure during 628 bypass system operations.
This gives a probability of bypass failure of 0.0048.
Combining the actual frequency of a generator load rejection with the failure rate of the bypass yields an frequency of a generator load rejection with bypass failure event of 0.0036/ plant year.
15.2.2.2 Secuence of Events and Svstem Operation 15.2.2.2.1 Sequence of Events 15.2.2.2.1.1 Generator Load Fejection - Turbine Control Valve Fast Closure A loss of generator electrical load from high power conditions
(
produces the sequence of events listed in Table 15.2-1.
15.2-3
DRAFT
- ' ^
The frequency basis presented below, which is based upon operating plant data, provides a sound basis for this event to be categorized as an infrequent incident with a frequency of 0.0036/ plant year, and a mean time between failure (MTBF) of 278 years. However, this basis is currently 4
under review by the NRC. As a result, this transient has been classified as an incident of moderate frequency, and it has been included as such in the analysis of plant transients subject to the corresponding safety criteria, i.e. MCPR. This event will remain classified as an incident of moderate frequency until the NRC approves the frequency basis given below, or another similar to it.
i 4
7' f
I i
4 f
I
~
('
15.2.2.5 Radiolocical Consecuences While the consequence of this transient does not result in fuel failure, it does result in the discharge of normal coolant activity to the suppression pool via MSRV operation.
Beccuse this activity is restricted tc the primary containment, there is no exposure to operating personnel.
This transient does not result in an uncontrolled release to the environment, so the plant operator can choose to leave the activity bottled up in the containment or discharge it to the environment under controlled release conditions.
If purging of the containment is chosen, the release will be in accordance with established technical specifications and, at the worst, would only result in a small increase in the yearly integrated exposure level.
15.2.3 TURBINE TRIP 15.2.3.1 Identification of Causes and Frecuency Classification 15.2.3.1.1 Identification of Causes A variety of turbine or nuclear system malfunctions will initiate a turbine trip.
Some examples are:
moisture separator and heater drain tank high levels, large vibrations, operational lockout, loss of control fluid pressure, low condenser vacuum, and reactor high water level.
15.2.3.1.2 Frequency Classification 15.2.3.1.2.1 Turbine Trip This transient is categorized as an incident of moderate frequency.
In defining the frequency of this transient, turbine trips that occur as a by-product of other transients, such as loss of condenser vacuum or reactor high level trip events, are not included.
However, spurious low vacuum or high level trip signals, which cause an unnecessary turbine trip, are included in defining the frequency.
In order to get an accurate event-by-event frequency breakdown, this division of initiating causes is required.
15.2.3.1.2.2 Turbine Trip with Failure of the Bypass fThis transient disturbance is categorized as an infrequent incident.
Fr aws:
(Frequency:
U.UU64/ plant year MTBE:
156 years Frecuency Basis:
As discussed in Section 15.2.2.1.2.2, the failure rate of the bypass is 0.0048.
Combining this with the turbine trip frequency of 1.33 events / plant year yields the frequency of 0.0064/ plant year.
15.2-7 1
10 ERA 9tm Insert B F
In a manner similar to that of the Generator Load Rejection with Bypass Failure event, this disturbance could also be categori,.ed as an infrequent incident with a frequency of 0.0064/ plant year and a MTBF of 156 years.
However, since the frequency basis below is not currently approved by the NRC, this event has been classified as an incident of moderate frequency, and it has been analyzed against the appropriate safety criteria, i.e.
MCPR. This event will remain classified as an incident of moderate frequency until the NRC approves the frequency basis given below, or another similar to it.
I