ML20206T752

Proposed Tech Specs,Modifying Automatic Depressurization Sys for Specific Transients Not Producing High Drywell Pressure Signal

ML20206T752
Person / Time
Site:	LaSalle
Issue date:	07/03/1986
From:	COMMONWEALTH EDISON CO.
To:
Shared Package
ML20206T723	List: ML20206T715 ML20206T752
References
1838K, NUDOCS 8607080219
Download: ML20206T752 (13)

Text

{{#Wiki_filter:. ATTAC15ENT B PROPOSED CHANGE TO APPENDIX A -TECHNICAL SPECIFICATIONS TO OPERATING LICENSE NPF-18 Revised Pages: NPF-18 3/4 3-24 3/4 3-25 3/4 3-27 3/4 3-28 3/4 3-29 3/4 3-32 3/4 3-33 3/4 5-1 B 3/4 5-1 B 3/4 5-2 1838K 8607080219 860703 PDR ADOCK 05000374 P PDR

t. 9 TADLE 3.3.3-1 EMERGENCY CORE COOLING SYSTEM ACTilATION INSTRUMENTATION i' e5 MINIMUM OPERABLE APPLICABLE 0 e. CHANNELS PER TRIP OPERATIONAL i i c: FUNCTION *) CONDITIONS ACTION i I i

a:

j G TRIP FUNCTION f A. DIVISION I TRIP SYSTEM 'l ia m 4 1. RilR-A (LPCI MODE) & LPCS SYSTEM I 2(b) 1, 2, 3, 4*, 5" 30 I a. Reactor Vessel Water Level - Low Low Low, Level 1 2(b)* 1, 2, 3 30 b. Drywell Pressure - High 1 1, 2, 3, 4", 5" 31 LPCS Pump Olscharge Flow-Low (Bypass) c. i d. LPCS and LPCI A Injection Valve Injection Line 1/ Valve 1, 2, 3 32 4 *, 58' 33 u3 Pressure-Low (Permissive) , 't* e'. LPCS and LPCI A Injectin'n Valve Reactor. 2 1,2,3 38 j - T Pressure-Low (Permissive) 4*, Sa 33 f. LPCI Pump A Start Time Delay Relay 1 1, 2,' 3, 4*, 5* 32 I i g. LPCI Pump A Discharge Flow-Low (8ypass) 1 1, 2, 3, 4*, 5* 31 g h. Manual Initiation 1/ division 1, 2, 3, 48, 5" ,34 i 2. AUTOMATIC DEPRESSURIZATION SYSTEM TRIP SYSTEM "A" l 2(b) 1, 2, 3 30 i 4 Reactor Vessel Water Level - Low Low Low, Level 1 1 a. ? j coincident with f, II l b. Or 11 Pressure - H10h 2 1,2,3 30 i ou ,9 leer 1 1,2,3 32 -c. d. Reactor Vessel Water Level - Low, Level 3 (Permissive) 1 1,2,3 32 LPCS Pump Discharge Pressure-liigh.(Permissive) 2 1,2,3 32 i e. f. LPCI Pump A Discharge Pressure-liigh (Permissive) 2 1,2,3 32 f l g. Manual Initiation 1/ division 1, 2, 3 34 4 l h. Drywa Pressore. Bypass Timec 1 1, 2, 3 32 1 L. N AAtoAl.3*o k* hiY ~ s ib 3 / d.'u's ieu I, 2, 3 3i j i*

1 i 5 TABLE 3.3.3-1,(Continued) To EMERGENCY Code COOLING SYSTEM ACTUATION INSTRUMENTATION HINIMUM OPERABLE APPLICABLE m CilANiiELS PER TRIP OPERATIONAL i s i c: FUNCTION *I CONDITIONS ACTION I i TRIP FUNCTION i s i i. 8. DIVISION 2 TRIP SYSTEM 4 1. RilR8&C(LPCIMdDE) l 2(b) 1, 2, 3, 4*, 5" 30 Reactor Vessel. Water Level - Low, Low Low, level 1 l a. 2 1,2,3 30 f b. Drywell Pressure - liigh LPCI 8 and C Injection Valve Injection Line Pressure-Low 1/ valve 1, 2, 3 32 c. 4*, 5* 33 (Permissive) 1 1,2,3,4*,5* 32 { w d. LPCI Pump 8 Start Time Delay Relay LPCI Pump Discharge Flow - Low (8ypass) 1/ pump 1, 2, 3, 4*, 5* 31 [, e. 1/ division 1,2,3,4*,5* 34 s'o f. Manual Initiation 2 1, 2, 3, 38 l g. LPCI 8 and C Injection Valve Reactor 4*, Sa 33 Pressure-Low (Permissive) AUTOMATIC DEPRESSURIZATION SYSTEM TRIP SYSTEM "B"# 2. l I} 1, 2, 3 30 Reactor Vessel Water Level - Low Low Low, Level 1 2 h-a. coincident with NI 1, 2, 3 30 2 f 11 Pressure - High D$:oss b. 3*605 Timer 1, 1, 2, 3 32 t a c. 3 d. Reactor vessel Water Level,- Low, Level 3 (Permissive) 1 1,2,3 32 LPCI Pump 8 and C Discharge Pressure - til0h e. 2/ pump 1, 2, 3 32 (Permissive) 1/ division 1, 2, 3 34 i f. Manual Initiation g. Dcywe.it Pressore. Bypst Th,. i 3, 2, 3 32. j h. Manual L:li;n,:t .1/J:ws;a 1, 2, 3 39 -{L

TABLE 3.3.3-1 (Continued) EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTATION. ACTION ACTION 30 - With the number of OPERABLE channels less than required by tne _ Minimum OPERABLE Channels per Trip Function requirement: With one channel inoperable, place the inoperable channel a. in the tripped condition within one hour

• or declare the associated system inoperable.

b. With more than one channel inoperable, declare,the associated system inoperable. ACTION 31 - With the number of OPERABLE channels less than required by the Minimum OPERABLE channels per Trip Function, place the inoperable channel in the tripoed condition within one hour; restore the inoperable channel to OPERABLE status within 7 days or declare the associated system inoperable. ACTION 32 - With the number of OPERABLE channels less than required by .the Minimum OPERABLE Channels per Trip Function requirement, declare the associated ADS trip system or ECCS inoperable. ACTION 33 - With the number of OPERABLE channels less than the Minimum OPERABLE Channels per Trip Function requirement, place the inoperable channel in the tripped condition within one hour. ACTION 34 - With the number of OPERABLE channels less than required by the Minimum OPERABLE Channels per Trip Function requirement, restore the inoperable channel to OPERABLE status within 8 hours or declare the associated A05 valve or ECCS inoperable. I fde sydes ACTION 35 - With the number of OPERABLE channels less than required by the Minimum OPERABLE Channels per Trip Function requirement For one trip system, place that trip system in the tripped a. condition within one hour

• or declare the HPCS system inoperable.

For both trip systems, declare the HPCS system inoperable. b. ACTION 36 - With the number of OPERABLE channels less than required by the Minimum OPERABLE Channels per Trip Function requirement, place at least one inoperable channel in the tripped condition within one hour

• or declare the HPCS system inoperable.

ACTION 37 - With the number of OPERABLE channels less than the Total Number of Channels, declare the associated emergency diesel generator inoperable and take the ACTION required by Specification'3.8.1.1 or 3.8.1.2, as appropriate. "The provisions of Specification 3.0.4 are not applicable. LA SALLE - UNIT 2 3/4 3-27

L_ e.. .e AJo CH A A16-ES C*1 TMIS P A G E FOR R.EFBlBJcq CNLY TABLE 3.3.3-1 (Continued) EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTATION ~ ACTION ACTION 38 With the number of OPERABLE channels less than required by the Minimum OPERABLE Channels per trip function requirements: a. With one channel inoperable, remove the inoperable channel within one hour; restore the inoperable channel to OPERABLE status within 7 days or declare the associated ECCS systems inoperable. b. With both channels inoperable, restore at least one channel to OPERABLE status within one hour or declare the associated ECCS system inoperable. 5 ~ e 6 e f 4 4 e e e 6 l LA SALLE - UNIT 2 3/4 3-27(a) 9 _.. _. ~. _. _ ~.. _,,,.. _...... _ ~ - _. -. _,.....,.

s. i TABLE 3.3.3-2 9 EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTATION SE1 POINTS ALLOWADLE r-TRIP FUNCTION TRIP SETP0lNT VALUE 3 k ' A. DIVISION 1 TRIP SYSTEM

i

-i . N , 1. RilR-A (LPCI MODE) AND LPCS SYSTEM a. Reactor Vessel Water Level ' Low Low Low, Level 1 1-129 inches

• 1-136 inches
• j b.

Drywell Pressure - liigh i 1.69,psig $ 1.89 psig c. LPCS Pump Discharge Flow-Low 1 750 gpa 1 640 gpa d. LPCS and LPCI A Injection Valve Injection Line-500 psig 500 1 20 psig Low Pressure Interlock e. LPCS and LPCI A Injection Valve Reactor 500 psig 500 1 20 psig ' - Pressure-Low Pressure Interlock i f.- LPCI Pump A Start Time Delay Relay 1 5 seconds 5 6 seconds } g. LPCI Pump A Discharge Flow-Low 1 1000 gpa > 550 gpa m h. Manual Initiation N.A. H.A. w i 2. AUTOMATIC DEPRESSURIZATION SYSTEM TRIP SYSTEM "A" Reactor Vessel Water Level - Low Low Low, Level 1 1-129 inches" 1-136 inches

• 4 a.

l

b..Drywell Pressure - liigh 1 1.69 psig

$ 1.89 psig

c..'-ABS T imer

~ < 105 secomis < 117 seconds 'l l Id%A d. Reactor Vessel Water Level-Low, level 3 [12.5 inches * [11 inches

• i LPCS Pump Discharge Pressure-liigh 1 146 psig, increasing 1 136 psig, increasing e.

f. LPCI Pump A Discharge Pressure-liigh 1 119 psig, increasing 1 106 psig, increasing g. Manual Initiation N.A. N.A.

h. Dqwelt Pressor. Bypass m ec Sq,o u;uot j; 44,4 g3 s-ManvsI rukk+

u.a. n.a. l in:ha% liaer oad 4ks drywell p reswee. assoaakt ta:LL 4 Ab W) Th run f A line delaysless 4Lon or ayaal k se, socouJg. hvfsss her skalt ha N

1 TADLE 3.3.3-2 (Continued') l 9 EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTATION SETrolNTS u. O ALLOWABLE [i 1 RIP FUNCTION TRIP SETPOINT VALUE b 8. DIVISION 2 TRIP SYSTEM -4

k. RilR 8 AND C (LPCI MODE)

N a. Reactor Vessel Water Level - Low Low Low, Level 1 1-129 inches

• l-136 inches
• b.

Drywell Pressure - liigh 5 1.69 psig i 1.89 psig c. LPCI B and C Injection Valve Injection Line 500psip 500 1 20 psig j Low Pressure Interlock d. LPCI Pump B Start Time Delay Relay 5 5 seconds 5 6 seconds e. LPCI Pump Discharge Flow-Low 1 1000 gpm 1 550 gpa j f. Manual Initiation N.A. N.A. g. LPCI 8 and C Injection Valve Reactor 500 psig 500 1 20 psig w ) Pressure. Low Pressure Interlock -.y .l 5 2. AUTOMATIC DEPRESSURIZATION SYSTEM TRIP SYST[M "8" a. Reactor Vessel Water Level - Low Low Low, Level 1 1-129 inches" l-136 inches

• l j

b. Drywell Pressure - liigh 1 1.69 psi 0 1 1.89 psig i d. Reactor Vessel Water Level-Low, Level 3 i 105 seconds 1 117 seconds l y,;4ini;ou c. Timer > 12.5 inches * > 11 inches * [119psig, increasing i 106 psig, increasing LPCI Pump 8 and C Discharge Pressure-Iligh j-e. f. Manual Initiation N.A. H.A. l Dcywell Pressore. Byg> Ass %er g q,

pg

, g4,gg g

h. Muual skit g,g, g, g, 3

4 1 } j i 3 t l g,) r$e Som el M dime deIAVE A130Ci A Y 5.4k -IE4 AD$ [#ld! Adieu dimer os d ryWell fretigre, by(Ass dater sla.tl h4 less b or ego,Al 40 b U S'C**' ds. ' i 1 i4 4

o. i 9 TAPtE 4.3.3.1-1 EMERGENCY CORE COOLING SYSTEM ACTUATI0li INSTRUMENTATION SURVEILLANCE REQUIREMENTS r-E CilANNEL OPERATIONAL l CilANNEL FUNCTIONAL CilANNEL CONDITIONS FOR WHICH f5 TRIP FUNCTION CllECK TEST CALIBRATION SURVEILLANCE REQUIRED l l c A. DIVISION I TRIP SYSTEM I 1. RilR-A (LPCI MODE) AND LPCS SYSTEM g a. Reactor Vessel Water Level - Low Low Low, Level 1 S M R 1, 2, 3, 4*, Sa b. Drywell Pressure - liigh NA M Q 1, 2, 3 c. LPCS Pump Discharge Flow-Low NA H Q. 1, 2, 3, 4*, 5* d. LPCS.and LPCI A Injection Valve Injection Line Pressure low . Interlock NA M R 1, 2, 3, 4*, 5" e. LPCS and LCPI A Injection Valve 3 Reactor Pressure Low Interlock NA M R 1, 2, 3, 4*, 5" w f. LPCI Pump A Start Time Delay 2, Relay-NA H Q 1.,2. 3, 4*, 5" w g. LPCI Pump A Flow-Lim NA M Q 1, 2, 3, 4*, 5* N h. Manual Initiation NA R NA 1, 2, 3, 48, 5* AUTOMATIC DEPRESSURIZATION SYSTEM TRIP SYSTEM "A"# 2. a. Reactor Vessel Water Level - -i l Low Low Low, Level 1 5 M R 1, 2, 3 g;4;p,4;.a

c. -ADS Timer NA M

Q 1, 2, 3 l b. Drywell Pressure-Iligh NA M Q 1, 2, 3 \\ l d. Reactor Vessel Water Level - Low, Level 3 S M R 1, 2, 3 e. LPCS Pump Discharge Pressure-Ill0h NA H Q 1, 2, 3 f. LPCI Pump A Discharge Pressure-liigh - NA M Q 1, 2, 3 g. Manual Initiation NA R NA 1, 2, 3 h, Ocywell Pressore,0ypan Timec AJA ti CL l h,3 a i,. Mauv41 Lh; bit NA R NA 1,1. 3 t i Q

i 1 -i l C TABLE 4.3.3.1-1 (Continued) h EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTATION SURVEILLANCE REQUIREMENTS i CHANNEL OPERATIONAL i CHANNEL FUNCTIONAL CHANNEL CONDITIONS FOR WHICH 'E c .5 TRIP FUNCTION CllECK TEST CALI8RA' TION SURVEILLANCE REQUIRED -l 8. DIVISION 2 TRIP SYSTEM l 1. RilR 8 AND C (LPCI MDOE) a. Reactor Vessel Water Level - 4 Low Low Low, Level 1 5 M i -R 1, 2, 3, 4*, 5* b. Drywell Pressure - High NA M q 1, 2, 3 1 c. LPCI 8 and'C Injection Valve Injection Line Pressure Low j Interlock NA M R , 1, 2, 3, 4*, 5" l l d. LPCI Pump B Start Time Delay j - 1 Relay NA M Q 1, 2, 3, 4", 5* l w Q .1, 2, 3, 4*, 5" i e. LPCI Pump Discharge Flow-Low NA M j J ' 2," f. Manual Initiation MA R NA 1, 2, 3, 4*, 5* i } g. LPCI B and C Injection Valve Reactor Pressure Low Interlock NA M R 1, 2, 3, 4*, Sa j AUTOMATIC DEPRESSURIZATION SYSTEM TRIP SYSTEM "B"# l 2. a. Reactor Vessel Water Level - ] Low Low Low, Level 1 5 M R 1, 2, 3 b. Drywell Pressure-High NA M Q

1. 2, 3 L;4:nbr c.

A0fr Timer NA M Q 1, 2, 3 l d. Reactor Vessel Water. Level - ) Low, Level 3 5 M R 1, 2, 3 4 j e. LPCI Pump 8 and C Discharge Pressure-liigh NA M Q 1, 2, 3 . Manual Initiation NA R f. NA 1, 2, 3 I-

g. Dey.ett Preuurt. 6gan he gg g

Q 1'2.,3 1 l

h. Mauvat LL:b;t A/A R

NA I, 2., 3 1 j g 1_ j i

3/4.5 EMERGENCY CORE COOLING SYSTEMS ~ 3/4.5.1 ECCS - OPERATING t LIMITING CONDITION FOR OPERATION 3.5.1 ECCS divisions 1, 2 and 3 shall be OPERABLE with: a. ECCS division 1 consisting of: l 1. The OPERA 8LE low pressure core spray (LPCS) system with a flow path capable of taking suction from the suppression chamber and transferring the water through the spray sparger to the reactor vessel. 2. The OPERA 8LE low pressure coolant injection (LPCI) subsystem "A" of the RHR system with a flow path capable of taking suction from the suppression chamber and transferring the water to the reactor vessel. 3. At least 6 OPERA 8LE ADS valves. l 1 b. ECCS division 2 consisting of: 1. .The OPERA 8LE low pressure coolant injection (LPCI) subsystems "B" and "C" of the RHR system, each with a flow path capable of-l taking suction from the suppression chamber and transferring the 1 water to the reactor vessel. 2. At least 6 OPERA 8LE ADS valves. [ j ~ c. ECCS division 3 consisting of the OPERABLE high pressure core spray (HPCS) system with a flow path capable of taking suction from the suppression chamber and transferring the water through the spray sparger to the reactor vessel. APPLICABILITY: OP'ERATIONAL CONDITION 1, 2*# and 3*. i l 4 " The A05 is not required to.be OPERABLE when reactor steam dome pressure is less than or equal to 122 psig. i l See Special Test Exception 3.10.6. dd 5,, s c:ficakes 3.3.3 er +c:p sys4e 4 opscAW j t LA SALLE UNIT 2 3/4 5-1 .. m

3/4.5 EMERGENCY CORE COOLING SYSTEM BASES l 3/4.5.1 and 3/4.5.2 ECCS - OPERATING and SHUTDOWN ECCS Division 1 consists of the low pressure core spray system, low pressure coolant injection subsystem "A" of the RHR system, and tne automatic = depressurization system (ADS) as actuated by A05 trip system "A". ' ECCS Division 2 consists of low pressure coolant injection subsystems "B"and "C" 4 of the RHR system and the automatic depressurization system as actuated by ADS trip system "B". The low pressure core spray (LPCS) system is provided to assure that the i core is adequately cooled.following a loss-of-coolant accident and provides adequate core cooling capacity for all break sizes up to and' including the l double-ended reactor recirculation 1.ine break, and for, smaller breaks following depressurization by the ADS. ' Qgg g 1 The LPCS is a primary source of emergency core cooling after the reactor j vessel is depressurized and a source for flooding of the core in case of J { accidental draining. The surveillance requirements provide adequate assurance that the LPCS i system will be OPERABLE when required. Although all active components are testable and full flow can be demonstrated by recirculation through a test loop during reactor operation, a complete functional test requires reactor-shutdown. The pump discharge piping is maintained full to prevent water hammer damage to piping and to start' cooling at the earliest moment. The low pressure coolant injection (LPCI) mode of the RHR system is i provided to assure that the core is adequately cooled following a loss-of-coolant accident. Three subsystems, each with one pump, provide adequate core flooding for all break sizes up to and including the double-ended reactor recirculation i line break, and esmall breaks following depressurization by the ADS. I 1 .mm The surveil ance requirements provide adequate assurance that the LPCI i system will be OPERABLE when required. Although all active components are I testable and full flow can be demonstrated by recirculation through a test loop during reactor operation, a complete functional test requires reactor shutdown.- The pump discharge piping is maintained full to prevent water hammer damage to piping and to start cooling at the earliest moment. ECCS. Division 3 consists of the high pressure core spray system. The high pressure core spray (HPCS) system is provided to assure that the reactor core is adequately cooled to limit fuel clad temperature in the event of a 4 small break in the reactor coolant system and loss of coolant which does not result'in rapid depressurization of the reactor vessel. The HPCS system permits the reactor to be shut down while maintaining sufficient reactor vessel water level inventory until the vessel is depressurized. The HPCS system operates over a range of 1160 psid, differential pressure between reactor vessel and HPCS suction source, to O psid. The capacity of the HPCS' system is selected to provide the required core j cooling. The HPCS pump is designed to deliver greater than or equal to 516/1550/6200 gpa at differential pressures of 1160/1130/200 psid. Initially. water from the condensate storage tank is used instead of injecting water from LA SALLE - UNIT 2 B 3/4 5-1

f t EMERGENCY CORE COOLING SYSTEMS i BASES i ECCS-OPERATING and SHUTDOWN (Continued) the suppression pool into the reactor, but no credit is taken in the hazards analyses for the condensate storage tank water. { ' With the HPCS system inoperable, adequate core cooling is assured by the OPERA 8ILITY of the redundant and diversified automatic depressurization system. 4 and both the LPCS and LPCI systems. In addition, the reactor core isolation cooling (RCIC) system, a system for which no crsdit is taken in the hazards analysis, will automatically provide makeup at reactor operating pressures on a reactor low water level condition. The HPCS out-of-service period of 14 days is based on the demonstrated OPERABILITY of redundant and diversified low pressure core cooling systems. The surveillance requirements provide adequate assurance that the HPCS system will be OPERABLE when required. Although all active components are testable and full flow -can be demonstrated by recirculation through a test i loop during re. actor operation, a complete functional test with reactor vessel injection requires reactor shutdown. The pump discharge piping is maintained full to prev 9.nt water hammer damage and to provide cooling, at the earliest gement. Upon failure of the HPCS system to function properly,: m;r ; k i urre 1 .;;11 M;d / 2 -1;;: :f ;;;1;r.t :::H:nt,- the automatic depressurization Sys.. tem (ADS) automati-j cally causes selected safety relief valves tr. open, depressurizing the reactor so that flow from the low pressure core cooling systems can, enter the core in time j to limit fuel cladding temperature to less than 2200'F. A05 is conservatively required to be' OPERABLE whenever reactor vessel pressure exceeds 122 psig even t though low pressure core cooling systems provide adequate core cooling up to 1 350 psig. ADS automatically controls seven selected safety-relief valves. Six valves are required to be OPERABLE although the hazards analysis only t'akes credit for five valves. It is therefore appropriate to permit one of the I required valves to be out-of-service for up to 14 days without materially l reducing system reliability. 3/4.5.3 SUPPRESSION CHAMBER i 1 j The suppression chamber is also required to be OPERABLE as part of the j ECCS to ensure that a sufficient supply of water is available to the HPCS, LPCS and LPCI systems in the event of a LOCA. This limit on suppression t chamber minimum water volume ensures that sufficient water is available to permit recirculation cooling flow to the core. The OPERABILITY of the suppression chamber in OPERATIONAL CONDITIONS 1, 2 or 3 is required by Specification 3.6.2.1. ~ l Repair work night require making the suppression chamber inoperable. j This specification will permit those repairs to be made and at the same time 4 give assurance that the irradiated fuel has an adequate cooling water supply when the suppression chamber must be made inoperable, including draining, in OPERATIONAL CONDITION 4 or 5. j In OPERATIONAL CONDITION 4 and 5 the suppression chamber minimum required water volume is reduced because the reactor coolant is maintained at or below j 200*F. Since pressure suppression is not required below 212*F, the minimum water volume is based on NPSH, recirculation volume, vortex prevention plus a 2'-4" safety margin for conservatism. .l LA SALLE - UNIT 2 8 3/4 5-2 .Z. '. .I. . ad

ATTACISBNT C SIGNIFICANT HAZARDS CONSIDERATION I \\ commonwealth Edison has evaluated the proposed Technical Specification Amendment and determined that it does not represent a significant hazards consideration. Based on the criteria for defining a significant hazards j consideration established in 10 CFR 50.92, operation of LaSalle County Station Unit 2 in accordance with the proposed amendment will not:

1) Involve a significant increase in the probability or consequences of an accident previously evaluated because the revised ADS logic doesn't affect automatic depressurization for events where high drywell pressure occurs. This modification automates the function of reactor vessel blowdown for events where high drywell pressure does not occur. Under these conditions, manual operation of the ADS system is called for by l

the emergency operating procedures and was assumed in Chapter 15 of the UFSAR. I

2) Create the possibility of a new or different kind of accident from any j

accident previously evaluated because automatic depressurization is j analyzed and required for events where high pressure coolant sources are l unavailable and reactor vessel level is low. This change only automates what were previously manual operator actions.

3) Involve a significant reduction in the margin of safety because the j

upgraded logic provides additional margin of safety for events where high drywell pressure does not occur while still providing the same level of protection for events where high drywell pressure does occur. Based on the preceding discussion, it is concluded that the' proposed t system change clearly falls within all acceptable criteria with respect to the system cr component, the consequences of previously evaluated accidents will not be increased and the margin of safety will not be decreased. Therefore, based on the guidance provided in the Federal Register and the i criteria established in 10 CFR 50.92(e), the proposed change does not 1 i constitute a significant hazards consideration. i k i i i 1838K i -}}