Text

Tech Specs for Redundant DHR Capability,Crystal River, Unit 3, Informal Rept
	ML20069G011
Person / Time
Site:	Crystal River
Issue date:	07/31/1982
From:	Farmer F; EG&G, INC.
To:	Donohew J; Office of Nuclear Reactor Regulation
References
	CON-FIN-A-6429 EGG-EA-5898, TAC-42121, NUDOCS 8303240268
	Download: ML20069G011 (18)
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t 04 EGG-EA "'198 July 1982 bR TECHNICAL SPECIFICATIONS FOR REDUNDANT DECAY HEAT ggg REMOVAL CAPABILITY, CRYSTAL RIVER, UNIT NO. 3

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F. G. Farmer j

U.S. Department of Energy Idaho Operations Office

Idaho National Engineering Laboratory

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This is an informal report intended for use as a preliminary or working document Prepared for the U.S. Nuclear, Regulatory Commission Under DOE Contract No. DE-AC07-761D01570 g

FIti No. A6429 g g g g idaho 8303240268 820731 PDR RES 8303240268 PDR

E Idaho, inc p

FOf4M EO&G JW (Ns0183 INTERIM REPORT Accession No.

Report No.

EGG-EA-5898 i

Contract Program or Project

Title:

Selected Operating Reactors Issues Program (III)

. Subject of this Document:

Technical Specifications for Redundant Decay Heat ".moval Capability, Crystal RNer, Unit No. 3 Type of Document:

l.

Informal Report Author (s):

F. G. Farmer Date of Document:

July 1982 Responsible NRC Individual and NRC Office or Division:

J. N. Donohew, Division of Licensing This document was prepared primarily for preliminary or internal use. it has not received full review and approval. Since there may be substantive changes, this document should not be considered final.

i EG&G Idaho, Inc.

l Idaho Falls, Idaho 83415 I

s Prepared for the U.S. Nuclear Regulatory Comminion Washington, D.C.

Under DOE Contract No. DE-AC07-761D01570 NRC FIN No.

A6429 INTERIM REPORT

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i TECHNICAL SPECIFICATIONS FOR REDUNDANT DECAY HEAT REMOVAL CAPABILITY CRYSTAL RIVER, UNIT NO. 3 July 1982 F

F. G. Farmer Reliability and Statistics Branch Engineering Analysis Division EG&G Idaho, Inc.

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l Docket No. 50-313 TAC No. 42121 i

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ABSTRACT This' report reviews the Crystal River, Unit No. 3 technical specifica '-

-tion requirements for redundancy in decay heat removal capability in all modes of operation.

FOREWORD This report is supplied as part of the " Selected Operating Reactors Issues Program (III)" being conducted for the U.S. Nuclear Regulatory Commission, Office of Nuclear Reactor Regulation,-Division of Licensing, by EG&G Idaho, Inc., Reliability and Statistics Branch.

The U.S. Nuclear Regulatory Commission funded'the work under the authorization, B&R 20 19 10 11, FIN No. A6429.

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4 Selected Operating Reactors Issues Program (III)

FIN No. A6429 '

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' CONTENTS

1.0 INTRODUCTION

1 2.0 REVIEW CRITERIA........................,.........................

1 3.0 D I SCUSS I ON AND EVAL U AT I ON.......................................

1 3.1 Startup and Power Operation--Modes 1 and 2................ -

1 3.2 Hot Standby--Mode 3.......................................

2 3.3 Hot and. Cold Shutdown--Modes 4 and 5......................

12 3.4 Re f ue l i ng -- Mode 6.........................................

3

4.0 CONCLUSION

S.....................................................

3

5.0 REFERENCES

4 APPENDIX A--MODEL TECHNICAL-SPECIFICATIONS FOR REDUNDANT DECAY HEAT REMOVAL FOR BABC0CK AND WILCOX PRESSURIZED

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WATER REACTORS (PWR's)..........................................

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TECHNICAL SPECIFICATIONS FOR REDUNDANT DECAY HEAT REMOVAL CAPABILITY

' CRYSTAL' RIVER UNIT,.NO.-3 l.0. INTRODUCTION A number of events have occurred at operating Pressurized Water Reactor (PWR)' facilities where decay heat removal capability has been seriously degraded.due to inadequate administrative controls during shutdown modes o{

. One of.these events, described in'.IE Information Notice 80-20, operation.

Bulletin 80-12g Davis-Besse Station, Unit No.1, on April 19, 1980.

In IE occurred at th dated May 9, 1980, licensees were requested to-immediately implement administrative controls which would ensure that proper means are available-to provide. redundant methods of decay heat removal. While the function of the l>ulletin was to effect immediate action with regard to this problem, the NRC' considered it necessary that-an amendment of each license be made to provide for permanent long term assurance that redundancy in decay heat removal'. capability will be maintained. By letter dated June 11, 1980,3 all PWR licensees were requested to propose technical specifica-tions (TS) changes'that provide for redundancy in decay he capabilityinallmodesofoperation;usetheNRCmodelTSgtremoval which provide an acceptable solution of the concern and include an appropriate safety-analysis as a basis; and submit the proposed TS with the basis by October 11, 1980.

^

2.0 REVIEW CRITERIA The review criteria for this task are contained in the' June 11,'1980, letter'from the NRC to all PWR licensees.._.The NRC provided-the model technical specifications which identify the' normal required redundan't coolant system and the required action when redundant systems are not available for a typical two loop plant (Appendix A). The purpose of this.

report is to review the licensee'.s TS and note any differences between them and the model TS as provided by the NRC.

l 3.0 DISCUSSION AND EVALUATION Crystal River, Unit No. 3 (CR-3) is a two coolant loop Babcock &

Wilcox (B&W) PWR plant. 'The following discussion presents an evaluation of the existing TS subm l

as requested by NRC.jtted by Florida Power for redundant decay heat removal p

CR-3's TS closely parallel the NRCimodel TS.

3.1 Startup and Power Operation--Modes 1 and 2 L

The NRC model TS require both coolant loops and both reactor coolant pumps in each loop to be in operation. With one of the four coolant pumps

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not ~in operation, STARTUP and POWER OPERATION may be initiated and may a

proceed provided thermal' power is restricted.

Within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months of losing one pump, the setpoints for the following trips are required to be reduced:

1) Nuclear Overpower, 2) Nuclear Overpower based on RCS flow and AXIAL POWER IPEALANCE, and 3) Nuclear Overpower based on pump monitors.

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b The CR-3 TS require both coolant. loops;and both reactor coolant pumps

_in each loop to be in operation. With one of the four coolant pumps not-in operation, STARTUP and POWER OPERATION may be_ initiated and may proceed provided thermal power is restricted.to_less than 79.925 of RATED THERMAL POWER and within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months the setpoint for the Nuclear Overpower Setpoint-is reduced; no mention is made of setpoint reduction for_ Nuclear. Overpower based on RCS flow and AXIAL. POWER IMBALANCE or pump monitors.

4 The. surveillance requirements of the CR-3 TS match those of the NRC model TS except that verification of coolant loop operation at least'once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months is not required..

3.2 Hot Standby--Mode 3 The NRC model TS require Reactor. Coolant Loop (A), Reactor Coolant Loop (B), and at least one associated reactor coolant pump in each loop to be operable in Mode 3.

At least one of the_ coolant loops and an associated pump must be in operation (all reactor coolant pumps may be de-energized

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for up to I hour provided (1) no operations are permitted that would cause dilution' of the reactor coolant system boron concentration, and (2) core outlet temperature is maintained at least 10*F below saturation temper-ature). With less than the above reactor coolant loops operable, the model TS require the loop (s) be restored to OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months ; otherwise the reactor must be in HOT SHUTDOWN within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . With no reactor coolant loop in operation, all operations involving a reduction in boron concentration must be suspended and immediate action must be taken to return the required. loop to operation.

The CR-3 TS require at least one reactor coolant loop in operation with either an associated re' actor coolant pump or decay heat removal pump; the TS contain no ACTION requirement equivalent to that of model TS' paragraph 3.4.1.2, nor do they contain surveillance requirements equ? valent to model TS paragraphs 4.4.1.2.1 and 4.4.1.2.2.

3.3. Hot and Cold Shutdown--Modes 4 and 5 t

l The NRC model TS require, in Modes 4 and 5, at least two of the following coolant loops to be operable: ReactorCoolantLoop(A), Reactor Coolant Loop (B),-(including their associated steam generators and at least one associated reactor coolant pump), Decay Heat Removal Loop (A) and Loop (B).a At least one of. the above coolant loops must be in operation.b With less than the required coolant loops operable, the model TS require immediate action to return the loop (s) to OPERABLE status as soon as possible or the plant must be in COLD SHUTDOWN within 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months .

With no coolant loops operating, all operations involving a reduction in boron concentration of the Reactor Coolant System must be suspended.

a.

The normal or emergency power source may be inoperable in MODE 5.

b.

All reactor coolant pumps may be de-energized for up to 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months provided (1) no operations are permitted that would cause dilution of the reactor coolant system boron concentration, and (2) core outlet temperature is maintained at least 10*F below saturation-temperature.

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l The CR-3 TS require at least'one reactor coolant loop in operation-

with either an associated reactor coolant-pump-or decay heat removal pump in Modas 4 and 5; in Mode 4.only, they also require that each steam generator and each decay heat removal loop'be'0PERA8LE.. ith less than W

L these OPERABLE,'the TS require immediate initiation of corrective action to return the required: systems-to OPERA 8LE~ states within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in at:

least' Hot Standby within the ~next 6 hour6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months s-and Cold Shutdown within the g

following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months ..

-The'CR-3 TS require decay heat' removal-loops be demonstrated to be

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t OPERABLE by verifying, at least once per 31. days,2that each applicable valve is,in its correct position; they contain no. surveillance requirements-equivalent to those of model TS paragraphs 4.4.1.3.2,.4.4.1.3.3,_

and'4.4.1.3.4.

8 3.4 Refueling--Mode 6 During refueling operations, the model.TS require at 1 east'-one decay 4

i heat removal (DHR) loop to be in operation. With less than one'DHR loop in operation, all. operations involving an increasc in the reactor decay heat load or a reduction.in boron concentration must be suspended..The model TS also require all containment penetrations-providing direct access from the containment atmosphere to the outside atmosphere be closed withinLfour

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hours. The DHR: loop may, howeverf be removed from operation for up'to I hour per 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months period during the. performance of CORE ALTERATIONS in.the vicinity of the reactor pressure vessel ~(hot) legs.

Dur'ing refueling when the water level labove the top of the irradiated fuel assemblies seated within the reactor: pressure vessel is less than

-23. feet, the.model.TS require two: independent DHR loops to be operable.a a

With less than two loops operable, inanediate corrective action must be taken to return the required loops,to OPERABLE' status as-soon as possible.

The CR-3 TS meet the-above requirement's:except that they do not.

require two' independent DHR loopsito be oper6ble with less than'23 feet of.

water above the top.of the irradiated fuel assemblies. The TS requires at i

least'one DHR be~ verified to be in operation'and circulating-reactor.

coolant at a flow rate of-at least 2700 gpm.at least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , as L

. compared with the model TS requirement of 2800 gpm verified at least once.

per 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .

4.0 CONCLUSION

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e' An evaluation of the existing TS for Crystal River, Unit No. 3, indicates they are in general agreement with the NRC model technical speci-fications for redundant decay heat, removal.. The following differences were noted and' discussed in previous secticns of this report e

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!1 a.

The normal or emergency power source may be inoperable for each DHR j

loop.

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LInl Modes 1 and 2,"no mention is made of:setpoint reduction for Nuclear Overpower. based. on'RCS flow and AXIAL' POWER IPSALANCE or--

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. pump. monitors,Cand verification of coolant: loop operation at least once per112 hours is not required.

2.

In. Mode-3, operation of a: reactor coolant pump;is:not required, _

nor are there' ACTION or surveillance requirements equivalent'to those-of the model TS..

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In ModeL4,: operation of a reactor coolant. pump is not required'

'and time limits for ACTION differ from those of the model TS, as.

do the5surveillanceLrequirements.-

> 4. _

In Mode 5, in addition.to the points-noted for Mode 4 steam' generators and DHR loops are not required to be operable.

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'In. Mode 6, there is'no requirement for two DHR loops to be-operable with -less1than-23 feet of water above the top of 4

-irradiated fuel. assemblies;-also, surveillance requirements differ slightly from the model:TS.

5.0 REFERENCES

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'.NRC IE Information Notice.80-20,- May 8,1980.

12.

'NRC IE Bulletin 80-12, May 1980.-

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NRC11etter,;D. G. Eisenhut, To all Operating Pressurized-Water. Reac-i

(-

tors (PWR's), dated June-11, 1980.

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.4.

Standard Technical Specifications for Babcock & Wilcox Pressurized.

Water Reactors, NUREG-0103-Rev. 3,' July'1979.

5.

Technical -Specifications for Crystal River, Unitt3,- revised through

' Amendment 46.

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.g-APPENDIX r J

MODEL TECHNICAL SPECIFICATIONS FOR REDUNDANT DECAY HEAT REMOVAL FOR BABC0CK & WILC0X PRESSURIZED WATER REACTORS (PWRs)'

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3/4'.4 REACTOR COOLANT SYSTEM 3/4.4.1 tCOOLANT LOOPS AND COOLANT-CIRCULATION

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-STARTUP AND POWER OPERATION 6e L-4

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,c LIMITING CONDITION FOR OPERATION

- 3.4.1.1 Bothlrea$ r coolant loops'and both N$bkor cookank p$ bps in each loop _shall be in operation.-

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APPLICABILITY: --MODES;l-and 2.* 4 c

ACTION:

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., x With one reactor coolant pump not in operation, STARTUP and POWER OPERATION may be initiated and may proceed provided THERMAL POWER.is restricted to less than ( )% of RATED THERMAL POWER and within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months the.setpoints' for the following trips have been reduced to the values specified in Specification 2.2.1 for operation with.three reactor coolant. pumps operating:

1.

(NuclearOverpower)...

' 2.

(Nuclear Overpower based on RCS flow and. AXIAL POWER IMBALANCE).

3.

(Nuclear Overpower based on purp monitors).

SURVEILLANCE REQUIREMENT 4.4.1.1 The above required reactor coolant loops shall be verified to be in operation and circulating reactor coolant at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

14.4.1.2 The Reactor Protective Instrumentation channels specified in the.-

applicable ACTION statement above shall be verified to have had their trip setpoints changed to the values specified in Specification 2.2.1 for the applicable number of reactor. coolant pumps operating either:

a.

Within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .after switching to a different pump combination if the switch is made while operating, or b.

Prior to reactor criticality if the switch is made while shutdown.

See Special Test Exception 3.10.4.

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REACTOR' COOLANT SYSTEM HOT STAND 8Y LIMITING CONDITION FOR OPERATION 3.4.1.2

- a.

The reactor coolant loops listed below shall be OPERA 8LE:-

1.

Reactor Coolant Loop (A)_and'its associated reactor coolant ~ pump, 2.-

Reactor Coolant Loop (B) and its associated reactor.

-coolant pump, b.

'At least one of the above Reactor Coolant Loops shall be'in operation.*

APPLICABILITY: MODE 3-ACTION:

a.

With -less than the above required reactor coolant loops OPERA 8LE, restore-the required loops to OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in HOT SHUIDOWN within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

b.

With no reactor coolant' loop in operation,' suspend all operations 3

involving a reduction in boron concentration of the Reactor Coolant System and imediately ir.itiate_ action to return the required coolant loop to operation.

SURVEILLANCE-REQUIREMENT 4.4.1.2.1 At least the above required reactor coolant pumps, if not-in operation, shall be determined to be OPERA 8LE once per 7 days by verifying correct breaker alignments and indicated power availability.

4.4.1.2.2-At least one cooling loop shall be verified to be in operation and circulating reactor coolant at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

l All reactor coolant pumps may be de-energized for up to I hour provided (1) no operations are permitted that would cause dilution of the reactor coolant system boron concentration, and-(2) core outlet temperature is

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. maintained 'at least 100F below saturation temperature.

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- REACTOR COOLANT SYSTEM SHUTDOWN LIMITING CONDITION'FOR OPERATION'

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-m 3.4.1.3-a.

At least two of the coolant loops listed _below shall be' OPERABLE: :,s a

-1.c ReactorcCoolant Loop'(A)?and:its associated 4 team gen -

, m erator'and at least one: associated reactor coolant pump, 2[

Reactor. Coolant ' Loop (B)'- and its _ associated steam gen--

erator and at.least one associated reactor coolant pump, 3.

Decay: Heat-Removal. Loop"(A),*;

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4...DecayiHeatiRemoval. Loop (B),*

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At least one ofcthe.above coolant.. loops'shall be in operation.**

APPLICABILITY: MODES'4'and 5'.J ~

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ACTION:

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With-less than the above required loops OPERABLE, immediately initiate corrective action to return the required loops.to

' 0PERABLE status as soon 'as ~ possible; be in COLD SHUTDOWN within 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months .'

b.

With no coolant loop in operation, suspend all operations involving a reduction in boron concentration of the Reactor Coolant System and immediately initiate' corrective action to return the required coolant loop to operation.

The normal.or emergency power source may be inoperable in MODE 5.

- All reactor coolant pumps and decay heat removal 1 pumps may be de-energized for up to 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months provided (1) no operations are permitted that would cause dilution of the reactor coolant system boron concentration, and 0

(2)' core outlet temperature is maintained at least 10 F below saturation temperature.

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REACTOR COOLANT' SYSTEM SURVEILLANCE REQUIREMENT 4.4.1.3.1 The required residual _ heat removal. loop (s) shall-be determined 0PERABLE per Specification'4.0.5.

4.4.1.3.2< The. required-reactor coolant' pump (s),-if'not in operation,'shall' be. detennined to be OPERABLE once per. 7 days by verifying correct breaker alignments 'and.-Indicated power lavailabil_ity.

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4.4.1.3.3 The required steam-generator (s)'shall be determined OPERABLE by verifying secondary side level to be; greater than or equal to (

)%.

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4.4.1.3.4 At least one coolant loop shall be verified to be in operation and circulating reactor. coolant at:least once per =-12 hours.

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1 REFUELING OPERATIONS ~'

3/4.9.8 RESIDUAL ~ HEAT REMOVAL - AND COOLANT CIRCULATION ALL WATER LEVELS LIMITING CONDITION FOR OPERATION

..3.9.8.'l ~ At' leastione residual heat removal!(DHR) loop shallibe.in' operation.-

APPLICABILITY: MODE,

ACTION:

a. -

With less than one DHR -loop in operation, except as provided in

b. below,' suspend.all operations involving ~an increase in the-reactor decay heat load or a. reduction in boron concentration of the Reactor Coolant System. -Close all~ containment pnetrations

.providing direct access from the containment-abnosphere to the-outside atmosphere within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .-

b.

.The DHR loop may. be removed from ~ operation for up to 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months per.

8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months . period during the performance of CORE ALTERATIONS in the vicinity of the reactor pressure vessel'(hot) legs.

The provisions of Specification 3.0.3 are not applicable.-

c.

SURVEILLANCE. REQUIREMENT 4.9.8.1 At least one DHR loop shall be verified' to be. in operation and '

circulating reactor coolant at a flow rate of greater than or equal to (2800) gpm at least once per 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .

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REFUELING OPERATIONS LOW WATER LEVEL LIMITING CONDITION FOR OPERATION 3.9.8.2 Two independent DHR. loops shall be OPERABLE.*

APPLICABILITY: MODE 6 wh'en the water level above_the top of'the' irradiated fuel assemblies seated within'the reactor pressure vessel is less than 23 feet.

ACTION:

a.

With less than the required DHR loops OPERABLE,-immediately

. initiate corrective action.to return the required' loops to OPERABLE status as soon as possible.

b.

The provisions of_ Specification 3.0.3 are not applicable.

SURVEILLANCE REQUIREMENT 4.9.8.2' The required DHR loops shall be determined OPERABLE per Specifica-tion 4.0.5.

1 The normal or emergency power source may be inoperable for each DHR loop.

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~3/4.4 REACTOR COOLANT SYSTEM.

BASES 3/4.4.1 COOLANT LOOPS AND COOLANT CIRCULATION The plant'is designed to operate:with both reactor coolant loops:in operation, and maintain DNBR above (1.32/1.30) during all normal operations

.and anticipated transients.- With one reactor coolant, pump not in operation in one loop,- THERMAL POWER.is restricted by the Nuclear Overpower Based on -

- RCS_ Flow and AXIAL POWER 11EALANCE and the. Nuclear Overpower Based on Pump i

Monitors trip, ensuring that the DNBR'will be. maintained above (1.32/1.30) at the maximum possible THERMAL POWER for the number of reactor coolant pumps in operation ~ or the local quality at the point of minimum DNBR equal sto (22/15)%, whichever is more-restrictive.

In MODEL 3,- a single reactor coulant loop provides sufficient heat -

s removal capability for removing decay heat;-however,--single failure con-siderations require that two loops be OPERA 8LE.

In MODES 4 and 5, a single reactor coolant loop or DHR loop provides sufficient heat. removal capability for removing decay heat; but single failure considerations require that at least two loops be OPERABLE. Thus, if the reactor coolant loops are not OPERABLE,'this specification requires.

4

'two OHR loops to be OPERABLE..

The operation' of one Reactor Coolant Pump ~.or'one DHR-pump provides -

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adequate flow to ensure mixing, prevent stratification and produce gradual reactivity changes during boron concentration reductions in the Reactor Coolant-System. The reactivity change rate associated with boron reduction will, therefore, be within the capability of operator recognition and control.

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. REFUELING OPERATIONS ~

' BASES 3/4.9.8 DECAY HEAT REMOVAL AND COOLANT' CIRCULATION

-The_ requirement that at least one DHR loop.be in operation. ensures-

-: that -(1)csufficient' cooling capacity is available to remove decay. heat. and maintain the water in the~reactorLpressure vessel below 140 F as required 0

during the REFUELING MODE, and (2) sufficient coolant circulation is main-tained-through the reactor core'to minimize:the effect of_-a boron dilution incident and prevent boron ~ stratification.

4 The requirement-to have'two DHR loops OPERA 8LE when there is less than 23 feet of water above the core ensures ~ that a single! failure of-the oper-ating DHR loop will.not result-in a complete loss of ' decay' heat removal.

capability. With the-reactor' vessel head removed and 23 feet of water.

~ bove the core, a large heat sink is available for core cooling. Thus, in a

the event of a failure-of the operating DHR loop, adequate time'is provided to initiate energency procedures to cool the core.

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v t e Letter Sequence Other
TAC:42121, (Open)
Initiation Acceptance... Administration Questions Answers Results Approval... Other: ML20069G011
MONTHYEAR1982-07-31 [Table View]

ML20069G011

Text

Title:

1.0 INTRODUCTION

4.0 CONCLUSION

5.0 REFERENCES

4.0 CONCLUSION

5.0 REFERENCES

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