Text

Forwards Proposed Changes to Tech Specs for Control Room ESF HVAC & Related Instrumentation.Changes Incorporated Include Revised Action Statements Resulting from Combining Both Units Control Room & Disabling of Isolation Circuitry
	ML20205R734
Person / Time
Site:	Vogtle
Issue date:	11/01/1988
From:	Bailey J; GEORGIA POWER CO.
To:	; NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
	GN-1504, NUDOCS 8811100109
	Download: ML20205R734 (20)
	v • d • e

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e GecNia Fbwar Company l.

Fdst Off<e Bor 282 Waynesboro. Georgra 3083o

- - - m mim WaMal~"'c Birmingham, Alabama 35202 we 20s *** "

Vogtle Project November 1, 1988 U. S. Nuclear Regulatory Commission File:

X7BC35 ATTN: Document Control Desk Log: GN-1534 Washington, D. C.

20555 Plant Vogtle - Units 1,2 NRC Dockets 50-424, 50-425 Operating Licensee NPF-68, Contruction Permit CPPR-109 Technical Specification Chsnges for Control Room HVAC Gentlemen:

Attached are proposed chemges to the combined Units 1 and 2 Technical 4

Specifications for the control room engineered safety feature (ESF)

HVAC and related instrumentation.

The changes incorporated include revised action staterants resulting from combining both Units control rooms, disabling of the control room isolation circuitry for chlorine detection, and revision of the automatic start logic to prevent more than two of the four trains f rom automatically operating.

It should be noted that the current Unit 1 Technical Specifications were used as a basis for the attached marku',e and that justification for deviation from the Unit 1 Technical Spectilcations for control room HVAC and i

related instrumentation specifications is also provided.

The proposed FSAR changes associated with the control room HVAC were previously submitted by letter GN-1467 dated July 5,

19%.

Should s

i you have any questions concerning the proposed Technical Spacification changes, please inquire.

If necessary, we would be pleased to meet i

with you.

Sincerely.

f J. A. Bailey f

Project Licensing Manager JAB /TLW/wkl Attachment

l xc: NRC Regional Administrator J. E. Joiner, Esquire NRC Resident Inspector J. B. Hopkins (2)

P. D. Rice G. Bockhold, Jr.

i J. P. Kane R. J. Goddard. Escuhe g

l R. A. Thomas R. W. McManus B. W. Churchill, Esquire Vogtle Project File 8011100109 881101 PDR ADOCK 0500 4

P

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PLANT SYSTEMS 3/4.7.6 CONTROL ROOM EMERGENCY FILTRATION SYSTEM Glom m o n 5y sfe )

LIMITING COM0! TION FOR OPERATION CRfif5 3.7.6 independent Control Room Emergency Filtration Systems /shall be OPERA 8LE (Notes 1, 2, 3, 4).

JE *% r Un;+ in APPLICABILITY:d MODES 1, 2, 3, and 4.

MODES 5 and 6 during movement of irradiated fuel or movement of loads over irradiated fuel.

ACTION:

S 1, 2, 3 or 4:

See Tn s,, +

Wit a control Room Emergency Filtsation System inoperable, res the ino ble system to OPERA 8LE status within 7 days or be i l eas's HOT STANOS thin the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN w n the following 30 ho MODES 5, and 6 during sov of irradiated fuel or esent of loads over irradiated fuel:

With one Control Room Emerge tration Systes inoperable, a.

restore the inoperable syst

' OPERA 8LE status within 7 days or initiate and maintain op ton of tihe ocaining OPERA 8LE Control Room Emergency Filtr n Systes in the rgency acde, b.

With both Con Roos Emergency Filtration Sys inoperable, or with t ERABLE Control, Room Emergency Filtrat

System, requi be in the emergehcy.sode by ACTION a.

not able of ng powered by an OPERA 8LE emergency power so,urce, sus d all erations involving movement of irradiated fuel or movement o loads over irradiated fuel.

SURVEILLANCE REQUIRDENTS 4 7.6 Each Centrol Roos Emergency Filtration Systes shall be demonstrated GPERA8LE:

At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months by verifying that the control room a.

air temperature is less than or equal to 85'F l:

b.

At least once per 31 days on a STAGGERED TEST BAS!$ by initiating, from the control roce, flow (FI-12191, FI-12192) through tha HEPA filters and charcoal adsorbers and verifying that the systee operates for at least 10 continuous hours with the heater control circuit energized.

V0GTLE - UNIT 1 3/4 7-14 Amendment No. 9

PLANT SYSTEMS S

SURVE!LLANCE REQUIREMENTS (Continued) c.

At least once per la months or (1) after any structural maintenance on the HEPA filter or charcoel adsorter housings, or (2) following painting, fire, or chemical release in any ventilation zone communicating with the system by:

1)

Verifying that the filtration systes satisfies the in place testing acceptance criteria of greater than or equal to 99.95%

filter retention while operating the systes at a flow rate of 19,000 cfm 1105 and performing the following tests:

(a) A visual inspection of the control room emergency filtration systes shall be made before each DOP test or activated carbon sesorber section leak test in accordance with Sec-tion 5 of MSI N510-1900.

(b) An in place 00P test for the HEPA filters shall be performed in accordance with Section 10 of MSI N510-1980.

(c) A charcoal adsorber section leak test with a gaseous halo-genated hydrocarbon refrigerant shall be perfomed in accordance with Section 12 of ANSI' M510-1980.

2)

Verifying within 31 days after removal that a laboratory analysis of a representativs carbon sample obtained in accordance with Section 13 of M 5! N510-1980 meets the laboratory testing cri-terion of greater than or equal to 93.85 when tested with methyl todide at 30*C and 705 relative humidity.

i 3

3)

Verifying a system flow rate of 19,000 cfs + 105 during systes operation when tested in accordance with Section 8 of ANSI l

M510-1900.

L 1

d.

After every 720 hours0.00833 days 0.2 hours 0.00119 weeks 2.7396e-4 months of charcoal adsorber operation, by verifying, within 31 days after removal, that a laboratory analysis of a repre-sentative carbon sample obtained in accordance with Section 13 of ANSI NS10-1900 meets the laboratory testing criterion of greater than or equal to 99.85 when tested with methyl todide at 30*C and 705 relative humidity.

1 e.

At least once per la months by:

l 1)

Verifying that the pressure drop across the combined HEPA filters, charcoal adsorber banks and cooling coil is less than 7.1 inches Water Gauge while operating the system at a flow rate of 19,000 cfm + 105; 2)

Verifying that on a Control Room Isolation Test Signal, the sys-tem automatically switches into an energency mode of operation with flow through the HEPA filters and c.harcoal adsorter banks; i

V0GTLE - UNIT 1 3/4 7-15 i

PLANT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued)

[

3)

Verifying that the system maintains the control room at a positive pressure of greater than or equal to 1/8 inch Water Gauge at less than or equal to a pressurization flow of 1500 cfm l ',

relative to adjacent areas during system operation; 4)

Verifying that the heaters dissipate 11816 kW when tested in

' accordance with Section 14 of ANSI N510-1980; and that on a Control Room / Toxic Gas Isolation te the contro the system automatical (on dampers close nos and s'

isolation mode of operation 1 the HEPA fi 1

i f.

After each complete or partial replacement of a HEPA filter bank, by verifying that the HEPA filter banks remove greater than or equal to 99.95% of the 00P when they are tested in place in accordance with Section 10 of ANSI N510-1980 while operating the systas at a flow rate of 19,000 cfm i 105; and g.

After each complete or partial replacement of a charcoal adsorber bana, by verifying that the charcoal absorbers remove greater than I

or equal to 99.953 of a halogenated hydrocarbon refrigerant test gas when tested in place in accordance with Section 12 of ANSI N510-1980 while operating the system at a flow rate of 19,000 cfe 1 103.

e 1:

During Control Room Emergency Filtration System testing preceding 1 of the temporary control room wall, the Unit 1 Control Room / Unit 2 l

reso Control om differential pressure requirement of Specification 4.7.E.e.3 I

waived.

T waiver is contingent upon the capability to shut down th applicable Un HVAC systems and close the applicable Unit 1/ Uni HVAC i

Isolation dampers thin 4.5 minutes after receipt of a Unit 1 trol Room i

Isolation signal.

Note 2:

After commencase of Unit 1 Control Room ncy Filtration System flow balancing for two-it operation, verif tion cf control roos

)

pressurization in accordance wi ification.

6.e.3 is waived for a period not to exceed 7 days.

This er is ntingent upon receipt of l

acceptable test results for control rr,

.ssurization testing prior to breaching the tamporary control room l

Note 3:

Unit 2 Control Roon ncy Filtrit systen Fans (2-1531-N7-001 and 2-1531-N7-002) shall be ro led to prevent ation following the completion of the initial unit control room pressur tior. test (pursuant i

to Specification 4.7.

.3) after remov61 of the temporary ntrol room wall.

Note 4:

At less no Unit 2 Control Room isolation damper (2 114 or 2HV-12115) :

be locked closed and.both Unit 1 Control Room iso etion dampers (

-12114 and 1HV-12115) shall be locked open.

The Unit 2 Cc'htro1 j

Room i ation despers (2MV-12114 or 2HV-12115) may be opened when the Un 1

i Co 1 Room Emer ressurization) gency filtration System is operating in the emergency l

mode.

I V0GTLE - UNIT 1 3/4 7-16 Amendment No. 9 I

INSERT With both units in MODES 1, 2. 3. or 4:

a.

With one Control Room Emergency Filtration System inoperable, restore the inoperable system to OPERABLE status within 7 days OR initiate and maintain operation of one train of the CREFS in the unaffected unit in the emergency mode

OR within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months lock closed the affected and lock open the unaffected unit's OSA intake dampers and place the affected unit in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months , b.

With one Control Roon Energency Filtration System inoperable in each unit, restore each inoperable system to OPERABLE status within 7 days OR initiate and maintain operation of both remaining CREFS in the emergency mode, c.

With two Cuntrol Room Emergency Filtration Systems inoperable in a unit. Initiate and maintain operation of both trains of CREFS in the unaffected unit in the emergency mode OR within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months lock closed the affected and lock open the unaffected unit's OSA intake dampers and place the affected unit in at least HOT STANDBY within the next 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

With only one unit in MODES 1. 2, 3. or 4:

a.

With one Co.9 trol Roon Energency Filtration System inoperable in an operating unit, restore the inoperable system to OPERABLE status within 7 days OR initiate and maintain operation of one train of the CREFS in the shutdown unit in the energency mode *.

b.

With one Control Roon Emergency Filtration System inoperable in a shutdown unit, restore the inoperable system to OPERABLE status witnin 7 days OR either 1) lock closed the affected an' lock open the unaffected unit's OSA intake dampers OR 2) initiate and maintain operation of one train of CREFS in the operating unit in the emergency mode".

c.

With one Control Roon Emergency P11tration System inoperable in each unit. restore each inoperable system to OPERABLE status within 7 days OR lock closed the shutdown unit's OSA intake dampers and lock open the operating unit's OSA intake dampers and initiate and maintain operation of the remaining CREFS train in the shutdown unit in the emergency mode.

d.

With two Control Room Emergency Filtration Systems inoperable in an operating unit. Initiate and maintain operation of both CREFS trains in the shutdown unit in the emergency mode.

N1088086/VT

e.

With two Control Room Emergency Filtration Systems inoperable in a shutdown unit, either 1) lock closed the affected and lock open the unaffected unit's OSA intake dampers or 2) initiate and maintain operation of both trains of the CREFS in the opera +ing unit in the emergency mode.

Wi*h both units in MODES 5 or 6. during movement of irradiated fuel or movement of loads over irradiated fuel in either unit.

a.

With one Control Roon Emergency Filtration System inoperable, restore the inoperable system to OPERABLE status within 7 days OR either 1) lock closed the affected and lock open the unaffected unit's OSA intake dampers OR 2) initiate and maintain operation of one train of the CREFS in the unaffected unit in the emergency mode *.

b.

With one Control Room Emergency Filtration System inoperable in each unit, restore inoperable system to OPERABLE status within 7 days OR initiate and maintain operation of one train of CREFS in the emergency mode.

c.

With two Control Roon Emergency Filtration Systems inoperable in a unit, either 1) lock closed the affected and lock open the unaffected unit's OSA intake dampers OR 2) initiate and maintain operation of one train of the CREFS in the unaffected unit in the emergency mode.

d.

With three Control Room 2=ergency Filtration Systems inoperable, either

1) lock closed the OSA intake dampers of the unit with two inoperable systems and lock open the OSA intake dampers of the unit with one inoperable system and restore the one inoperable system to OPERABLE status within 7 days OR initiate and maintain operation of the remaining train of CREFS in the emergency mode OR 2) init! ate and maintain operation of the remaining train of CREFS in the emergency

mode, e.

With four Control Room Emergency Filtration Systems inoperable or with the OPERABLE CREFS required to be in the emergency mode by ACTION a, b, c, or d above not capable of being powered by an OPERABLE emergency power source, suspend all operations involving movement of irradiated fuel or movement of loads over irradiated fuel.

The initiated CREFS shall be Train B.

N1088080/VT

i TABLE 3.3-2 (Continued).

h ENGINEERED SAFETY FEATURES ACTUATION SYSTEM INSTRUENTATION m

1 MINIMUM MINIfRM TOTAL NO.

CHANNELS CHANNELS APPLICABLE l

E FUNCTIONAL UNIT OF CHANNELS TO TRIP OPERA 8LE MODES ACTION G

10. Control Room - Emergency f.-lMon 5 stem e

Mode Actuation 3

Gsker Gn'Nn a.

Manual Initiation 2

1 1 In c;&cr 1, 2, 3, 4, t/a t

$e, 6' 26d b.

Automatic Actuation Logic 6;+k<< Ua Un and Actuation Relays.

2 1

2 1,2,3,4, 5'

6*

k Rj0

{

c.

Safety Injaction See Functional Unit I above for all Safety Injection-

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initiating functions and requirements.

g,.g,, g,4 w

d.

Intake Radiogas Monitor 7

1 2

1,2,3,4, h

(RE-12116. RE-12117) 5*,6'

% Jt[

d

11. Fuel Handling Building Post i

]

Accident Ventilation Actuation F

a.

Manual Initiation 2

1 1

i j

b.

Fuel Handling Building 4

1 1

1 J

J Exhaust Duct Radiation Signal (ARE-2532 A&8 ARE-2533 A&B) i

{

c.

Automatic Actuation Logic 4

1 1

i j

j and Actuation Relays 2

k O

TABLE 3.3-2 (Continued)

S ACTION STATEMENTS (Continued)

I ACTION 24 - With the number of OPERABLE channels one less than the Total Number of Channels, restore the inoperable channel to OPERA 8LE status within 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months or declare the associated valve inoperable and take the ACTION required by Specification 3.7.1.5.

ACTION 25 - With the number of OPERA 8LE channels one less than the Minimum Channels OPERA 8LE requirement, be in at least HOT STANDBY within

.6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months ; however, one channel may be bypassed for up to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months for surveillance testing per Specification 4.3.2.1 provided the i

other channel is OPERA 8LE.

,9 fe.,s f a n,

ACTION 26-WiththenumberofOPERABLEchannelsonk';lesstha Channels OPERABLE requirement, restore.. in;rch channel to OPERA 8LE status within 7 days or within tt,e next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months initiate and maintain operation of the Control Roca Emergency VentilationSystemintheEmerp:t:ncy mode A i "'in :h n s h

' n;;; 2 h,.it'.'n 1 5:= init.

=d nint:i

r: tien " tt:

C =t d ": n "n r;= ri " =ti ht kr, 0,.t ir, tt R r;;r,;, r d_.

ACTION 27 - Net '.'nd.

ACTION 28 - M;t M d.

C 8 8 '"

e i

i f The initiated CRZFS shall be Train B unless Train B is inoperable.

l j

t i

l V0GTLE - UNIT 1 3/4 3-27 Amendment No. 3

(

INSERT ACTION 27 -

a)

With one channel inoperable in a unit, restore the inoperable channel to OPERABLE status within 7 days OR within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months initiate and maintain operation of one Control Room Energency Filtration System (CREFS) in the unaffected unit in the emergency mode *,

b) with one channel inoperable in each unit, restore each inoperable channel to GPERABLE status within 7 days OR within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months initiate and maintain operation of one CREFS in each unit in the emergency mode".

c)

With two channels inoperable in a unit, within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months either 1) initiate and maintain operation of the two.

CREFS in the unaffected unit OR 2) initiate and maintain operation of one CREFS in each unit in the emergency mode".

d)

With three channels inoperable, within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months initiate and maintain operation of *he two CREFS in the energency mode in the unit utth only one channel inoperable, e)

With four channela inoperable, within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months initiate and maintain operation of two CREFS in the emergency mode.

ACTION 28 -

a)

With one channel inoperable in a unit, restore the inoperable channel to OPERABLE status within 7 days.

OR within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months either 1) lock closed the affected and lock open the unaffected OSA intake dampers OR 2) initiate and maintain operation of one CRP,FS in the emergency mode *.

b)

With one channel inoperable in each unit, restore each inoperable channel to OPERABLE status within 7 days OR within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months initiate and maintain operation of one CREFS in the energency mode *.

c)

With two channels inoperable in a unit, within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months either 1) lock closed the affected and lock open the unaffected OSA intake despers OR 2) initiate and maintain operation of one CREFS in each unit in the energency mode *.

d)

With three channels inoperable, within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months either

1) lock closed the OSA intake dampers of the unit with two h4 operable channels and lock open the other OSA intake dampers and restore the remaining affected channel to OPERABLE status within 7 days OR initiate and maintain operation of one CREFS in the emergency mode' in the following 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months OR 2) initiate and maintain operation of one CREFS in each unit in the emergency mode

e)

With four channels inoperable, within I hour initiate and maintain operation of one CREFS in each unit in the emergency mode *.

8 The initiated CREFS shall be Train B unless Train 8 is inoperable.

i

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JUSTIFICATION FOR DEVIATION FRCM THE UNIT 1 TECHNICAL SPECIFICATIONS FOR CONTROL ROOM KVAC AND INSTRUMENTATION SPECIFICATIONS

Reference:

Letter GN-1467 dated July 5, 1988 As described in our letter of July 5, 1988 (GN-1467) the VEGP two unit combined control room envelope is served by four trains of safety related HVAC. Two trains are powered from Unit 1 and two are powered from Unit 2.

Each train has sufficient capacity to remove the combined control room heat load and pressurize the combined control room to 1/3 inch W.G. relative to adjacent areas. During normal plant operation the Control Room is served by a non-safety related HVAC system which draws in outside air makeup via either one of two outside air (OSA) intakes.

There is one intake associated with each unit.

Each air intake is provided with two redundant radiation monitors that are powered by the associated unit.

Upon detection of radiation in one OSA intake at or above the radiation monitor setpoint, each monitor will automatically initiate both of the associated unit's Control Room isolation CRI signals (CRI-A and CRI-B).

Each CRI signal functions to start its associated emergency HVAC system and isolate the normal HVAC system.

The lead lag logic described in the referenced letter will then permit only one of the emergency HVAC systems to start.

If high radiation levels are detected in both OSA intakes. all four CRI signals will be generated and two ESP HVAC systems will be initiated.

Upon receipt of a safety injec;1on (SI) signal in a unit the assoc;ated train's CRI will be generated. And as described above, if an SI-A and SI-B are generated, the lead / lag logic will permit only one HVAC system to start.

For your convenience attached are two sketches depicting the relationships between the instrumentation and the filtration units.

Tho basts of the two unit control roon HVAC Technical Specification retains the same criteria as the single unit Technical Specification. That is, the heat removal capability of the system is such that the equipment qualification temperatures are not exceeded, and the control room will remain habitab)e for personnel during and following all credible accident conditions (including i

meeting single failure criteria).

The control room dose analyses submitted with the reference letter assume that at most two Control Room Emergency Filtration Systems (CREES) supply OSA to pressurize the control room.

Similarly, the bases for the operability of the CREFS actuation instrumentation remains applicabla. These instruments provide redundant and diverse means for initiating a CRI in response to credible accidents in either unit (including meeting single failure criteria).

Credible accident conditions involve accidents that generate SI signals (applicable MODES 1 thro gh 4 only) and/or radiation releases.

Note, as descrfoed in the referenced letter liquefied chlorine gas will not be stored in quantities greater than 20 pounds.

Therefore, onsite chlorine releases are not considered credible accidents.

For other onsite chemical releases the operator has sufficient time to don breathing apparatus as described in FSAR section 2.2.

As such, the CREFS is not credited with mitigating these events.

Because each KVAC system has 100% heat removal capability, initiation of any HVAC syaten or the capability to initiate a system will meet the heat removal criteria and is not discussed any further.

JUSTIFICATION FOR CONTROL ROOM ACTION STATEMENTS PAuE 2 The limiting condition for operation and applicability statements for the CREFS Technical Specification have been revised to reflect that four CREFC are required and that the specification is applicable when either unit is in MODES

1. 2. 3. 4. or 5. or in MODE 6 during movement of irradiated fuel or movement of loads over irradiated fuel.

That is, the specification is applicable at all times unless both units are shutdown and no movement of irradiated fuel or movement of loads over irradiated fuel is occurring.

BOTH UNITS IN NODES 1. 2. 3. OR 4 - CREFS ACTION STATDENTS During MODES 1 through 4. the current Technical Specifications allow one of the two HVAC systems to be inoperable for 7 days resulting in a temporary loss of redundancy. After that time, the Unit is placed in a protected condition (i.e. safe shutdown).

ACTION at The proposed ACTION a. (two unit operation with one inoperable HVAC system),

maintains wording similar to that contained in the current Technical Specification. The difference lies primarily in allowing initiation and maintaining operation of one of the HVAC systems in the unaffected Unit in the emergency mode thereby precluding the need for shutdown. The affected and unaffected Units still meet the single failure criteria. In that an accident involving an SI or radiation signal would require two failures before no HVAC would be supplied (e.g. failure of the non-operating HVAC system to start and failure of the operating HVAC system to continue running).

In this manner the affected unit is maintained in a protected condition. As an alternative, the Technical Specification requires shutdown of the affected unit and locking closed /open of the OSA intake dampers, leaving the unaffected unit in a single failure proof mode fo.' radiation and SI. and removes the source of demand on the affected Unit for radiation and SI. 'F'oo,tnote # is applied to ensure that a single failure in the lead / lag circuitry does not lead to prolonged operation of more than two HVAC systems.

ACTION b The proposed ACTION b. (two unit operation with one HVAC system inoperable in each unit) applies the same allowed outage times as ACTION a to each unit (i.e. allows 7 days for repair). However after the 7 days if both of the operable HVAC systems are placed into operation (one in each unit) the control room would still be protected if one of the operating systems were to fall to continue running or an SI signal to one of the OPERABLE units was not generated (a single failure).

JUSTIFICATION FOR CONTROL ROOM ACTION STATEMENTS PAGE 3 ACTION c:

The "'GP Unit 1 Technical Specifications require that the unit be shut down if both HVAC systems are inoperable because the bases of the Technical Specifications can not be met (i.e. upon any demand no emergency HVAC would be available) However, with two unit operation if both HVAC systems are inoperable in a unit. the initiation of both of the unaffected units HVAC systems will place the affected unit in the protected mode and the unaffected unit will still meet the single failure criteria (e.g. SI demand on the affected unit and a single failure of one of the operating HVAC systems to continue running will leave the control room in a protected condition). This provides the rationale for ACTION c.

As an alternate the Tochnical Specifications require shutdown of the affected unit and locking closed /open of the OSA intake dampers, following the same rational as that described for ACTION a.

BOTH UNITS IN MODES 5 OR 6 DURING MOVEMENT OF IRRADIATED FUEL OR NOVEMENT OF LOADS OVER IRRADIATED FUEL - CREFS ACTION STATEMENTS In MODES 5 or 6 during movement of irradiated fuel, the current Technical Specifications again allow 7 days for repair when the control room can only be served by one HVAC system. As an alternative the Techaical Specifications permit the operable system to be placed in operation.

Initiation of the OPERABLE HVAC system places the control room in a protected condition.

If the system was not placed in operation. a single failure of the OPERABLE system to start upon demand would place the control room in an unprotected condition (no emergency HVAC).

With both control room HVAC systems inoperable the current Technical Specifications require that the movement of irradiated fuel or movement of loads over irradiated fuel be suspended. This is because the control room would be in an unprotected condition if a fuel handling accident were to occur.

The proposed technical specifications meet or exceed the current Technical Specification criteria.

ACTION at With one HVAC system inoperable, the differences between ACTION a and the current Unit 1 Technical Specifications are 1) the OSA intake associated with the inoperable HVAC system may be locked closed and the OSA intake resociated with the Unit that has two OPERABLE systems be locked opened and 2) that the HVAC system that is initiated must be one of the systems in the Unit that has two OPERABLE systems.

Isolation of the OSA intake of the Unit with the inoperable HVAC system ensures that all OSA entering the control room will be through a fully monitored and operational intake. Locking open the other OSA intake places that intake in s single failure proof mode.

Initiation of a HVAC system in the unaffected Unit (rather than the affected Unit) ensures thet upon a demand the affected unit will mest single failure (if the operable system would not start, the other Unit's system is already running) and upon demand from the affected unit's OSA intake only (not both OSA intakes) coupled with a single failure (the remaining system does not start) that the control room is protected.

This configuration also leavec the unaffected unit in a single failure proof condition. Application of footnote ensures that a single failure in the lead / lag circuitry does not lead to prolonged operation of more than tro HVAC systems.

JUSTlFICATION FOR CONTROL

?00M ACTION STATEMENTS PAGE 4 ACTION b:

The proposed ACTION a. for one HVAC system inoperable in each unit, maintains the same action as described for the current Technical Specifications.

However, because any one HVAC system can meet the heat removal and pressurization requirements. Initiation of either of the remaining OPERABLE HVAC systems will place the control room in a safe configuration. The Control Room exceeds current criteria for the existing one-unit Technical Specification in that a second KVAC system is available for manual start.

ACTION c The proposed ACTION c is based on the same principles described in ACTION a for locking closed the affected Unit's intake.

Locking the OSA intake closed prevents a demand on the inoperable systems from a radiation source.

Initiation of one of the remaining OPERABLE systems places the control room in the protected co.. figuration while meeting the single failure requirements for the unaffected Unit.

ACTION da The proposed ACTION d considers when (with three inoperable HVAC systems) the control room is only capable of being served by one NVAC system and is subject to the OPERABLE system not being started if the demand came from the OSA intake associated with the Unit with no OPERABLE NVAC systems.

Therefore, to ensure that the operator is protected in case of a radiation release ACTION d requires that the OSA intake with the 2 inoperable systems be locked closed (thereby removing the radiation demand on the affected Un!t's HVAC systems) and the restoration of the other system to OPERABLE status within 7 days or the OPERAHLE system is placed in service (this is consistent with the current Technical Specification requirements).

ACTION et The proposed ACTION e considers when (with all four systems inoperable) the contrul room has no means of emergency filtration.

As such, suspension of operations involving movement of irradiated fiidl or movement of load over irradiated fuel is appropriate. Therefore Action e is consistent with the current Technicsl Specifications.

WITH ONLY ONI UNIT IN MODES 1. 2. 3. OR 4_CREFS ACTION. STATEMENTS When one Unit is in NODES 1.2.3 or 4 and the other Unit is in MODES 5 or 6.

the criteria (SI. radiation and single failure) for the respective MODE have been applied conservatively to ensure that the control room is protected to at least the same level as the current Technical Specifications (e.g. when looking at a radiation event if Unit 1 is in NODE 1 and Unit 2 is in MODE 5 and not moving fuel, a demand on th' Unit 2 OSA intake is still postulated).

JUSTIFICATION FOR CONTROL ROON ACTION STATEMENTS PAGS 5 ACTION as In ACTION a. for one unit operating one unit in cold shutdown or refueling and I

one inoperable HVAC system in the operating Unit, initiation of one KVAC system in the shutdown Unit ensures, considering a single failure upon demand from the operating Unit's intake or SI signals, that the control room is in a protected configuration.

The shutdown unit is not required to meet SI demands and remains single failure proof from a radiation standpoint. Footnote # is applied to ensure that a single failure in the lead / lag circuitry does not lead to prolonged operation of more than two HVAC systems.

ACTION bi l

l In ACTION b. for one inoperable HVAC system in the shutdown Unit, the locking i

closed of the shutdown unit's OSA intake dampers takes away the source of a radiation demand for the shutdown unit.

The operating unit still meets the single failure criteria for SI and radiation events. The operation of one KVAC system in the operating unit protects the shutdown unit from a single failure upon demand from the shutdown unit OSA intake while maintaining all criteris for the operating unit.

Footnote s is applied to ensure that a single failure in the lead / lag circuitry does not leat to prolonged operation of more than two RVAC systems.

ACTION c:

In ACTION c. for one inoperable HVAC systen in each Unit, operation of the remaining HVAC system in the shutdown unit and locking closed the shutdown Units' OSA intake places the operating Unit in a single failure proof configuration from an SI or radiation demand standpoint, while placing the shutdown Unit in a radiation single failure proof configuration.

(Locking closed of the OSA intake dampers is required to prevent a radiation demand on the shutdown Unit's intake and a single failure of the operating system to continue running, placing the operating unit in an unprotected condition.)

ACTION di In ACTION d. for two inoperable KVAC systems in the cperating Unit, initiation of both of the KVAC systems in the shutdown Unit, places both Units in a protected single failure proof configuration. (Upon SI or radiation in the

(

operating Unit the control room is already in a protected configuration)

ACTION e:

In ACTION e. for two inoperable KVAC systems in the shutdown Unit, locking closed the affected Unit's OSA intake removes the sources of a radiation demand on the shutdown Unit. The operating Unit still meets the SI and radiation requirements, including a single failure.

If a radiation demand occurs the, the shutdown Unit is protected.

Initiation of both trains of the remaining KVAC systems ensures that an NVAC system would be running upon a radiation demand on the affected Unit's OSA intake. The operating Unit meets the St and radiation requirements considering single failure and the shutdown Unit is protected.

.c_

JUSTIFICATION FOR CONTROL R004 ACTION STATEMENTS PAGE 6 CREFS ACTUATION INSTRUMENTATION-ACTION STATEENTS The design of the HVAC systems serving the common control room does allow additional operational flexibility when considering the ACTION statements associated with inopecable instrumentation. The four 100% capacity CREFS trains servicing the control room allow the operators more options to place the control room in a safe or protected condition without requiring plant operations to stop, and still meet existing actuation requirements, single failure criteria and allowed outage times.

ACTION 26:

Manual initiation of the CREFS (ACTION 26) is possible from two distinct channels in each Unit.

The requirements of the current Techr.ical Specifications are unchanged except that the Minimum Channels OPERABLE is now specified as one in either Unit.

As stated above, each of the four CREFS trains is capable of providing 100% of the pressurization and heat removal requirements of the combined control room and therefore one operable channel of a total of four for manual initiation is sufficient. ACTION 26 was revised to delete the discussion regarding two channels inoperable because only one channel is required.

Footnote # is applied to ensure that a single failure in the lead / lag circuitry does not lead to prolonged operation of more than two HVAC systems.

ACTION 27:

The current Technical Specification ACTION statement for Automatic Actuation Logic and Actuation Relays require, for one channel inoperable, restoration within 7 days or initiation and maintenance of the CREFS in the emergency mode, and with both channels inoperable, within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months initiate and maintain operation of the CREFS in the emergency mode.

The criteria which was used in developing the ACTION statements for the combined Technical Specifications, l

I was that the unita should remain protected for the required postulated accidents and single failure considerations.

In certain cases, this requires initiation of two CREFS trains to ensure both units remain protected.

ACTION as ACTION a. for one channel inoperable in a Unit, parallels the current ACTION statement with two exceptions, the initiated CREFS is required to be in the unaffected unit. and footnote # is applied.

Initiation of the CREFS in the unaffected unit ensures that upon an SI or radiation demand on the affected unit, a failure of the remaining system to start or of the initiated system to continue to run does not leave the control room unprotected. Footnote 8 is applied to ensure that a single failure in the lead / lag circuitry does not lead to prol~onged operation of more than two KVAC systems.

JUSTIFICATION FOR CONTROL ROOM ACTION STATEMENTS PAGE 7 ACTION b:

The same rationale as described for ACTION a is applied when one automatic actuation logic channel is inoperable in each unit.

However to ensure that at least one system will be in operation and prolonged operation of three systems does not occur. Initiation of one systes in each b..li and application of footnote 8 is required.

(If only one system was initiated. failure to continue to run upon demand could lead to the Control Roon being unprotected.)

ACTION c With two channels inoperable in a Unit. Initiation of both CREFS in the unaffected unit or one in each unit protects the control room from a failure of the initiated system to continue to run upon demand in the affected unit.

ACTION di With three channels inoperable. Initiation of the two CREFS in the Unit with one inoperable automatic logic channel assures that at least one system will be in operation and that no more than two systems will run continuously upon a demand.

ACTION e:

With four channels inoperable. initiation of any two CREFS is acceptable because it assures that at least one system will be in operation and a demand would not lead to generation of a CRI (and subsequent operation of more than two CREFS).

Safety Injection The current Technical Specification requirements and ACTION statements associated with Safety injection Actuation instrumentation will be unchanged in the combined Technical Specification.

It is not possible to take advantage of the HVAC system design for these instruments without violating the other Technical Specification bases requirements. (redundant SI actuation must meet CDC S. and single failure criteria).

The current Technical Specification requirements are applied to each Unit individually.

ACTION 28 The intake radiosas monitor system allows the greatest use of the flexibility of the combined control room KVAC design. Where the current Technical Specifications give the operator essentia21y only two options for an inoperable monitor (s). (repair the inoperable channel (s) in 7 days or within a specified time period start a CREFS) before shutting down the plant, the proposed Action 28 provides alternatives to shutdown while still meeting the single failure criteria and SI response requirements. With two OSA intakes.

the control room can be placed in a radiation safe mode and protected against single failure, by either isolating the OSA intake with the inoperable monitors or ensoring operation of at least one CREFS in the emergency mode.

'a JUSTIFICATION FOR CONTROL ROOM ACTION STATEMENTS PAGE 8 regardless of what MODE either Unit is in.

Accounting for the larger number of combinations of inoperable channels in both units and the ability to completely isolate one OSA intake and still meet single failure criteria, results in an ACTION statement with five parts rather than two.

The allowed outage time for inoperable monitors and the time allowed for corrective initiation is consistent with the current Technical Specifications.

Footnote

is applied to ensure that a single tallure in the lead / lag circuitry does not lead to prolonged operation of more than two HVAC systems.

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