ML20095G862

Suppl 1 to Amend Applications 116 & 100 to Licenses NPF-10 & NPF-15,consisting of Proposed TS Change 407 Changing SR 4.7.5.b to Run Control Room Emergency Air Cleanup Sys Every 31 Days from 10 H to 2 H

ML20095G862
Person / Time
Site:	San Onofre
Issue date:	12/18/1995
From:	Rosenthal R SOUTHERN CALIFORNIA EDISON CO.
To:
Shared Package
ML20095G861	List: ML20095G857 ML20095G862 ML20095G865 ML20095G870 ML20095G873
References
NUDOCS 9512210344
Download: ML20095G862 (18)

Text

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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION Application of SOUTHERN CALIFORNIA )

EDIS0N COMPANY, H R . for a Class 103 Docket No. 50-361 License to Acquire, Possess, and Use a Utilization Facility as Part of Amendment Application Unit No. 2 of the San Onofre Nuclear No. 116 Generating Station i SOUTHERN CALIFORNIA EDIS0N COMPANY, H R . pursuant to 10 CFR 50.90, hereby i

submit Amendment Application No. 116.

]

t This amendment application consists of Proposed Technical Specification Change No. NPF-10-407, Supplement 1 to facility Operating License NPF-10. Proposed Technical Specification Change No. NPF-10-407, Supplement 1 is a request to revise Technical Specification 3/4.7.5, " Control Room Emergency Air Cleanup System." The proposed change will delete Surveillance Requirements 4.7.5.c.1, and 4.7.5.e.5, and revise Surveillance Requirement 4.7.5.b, the ACTION statement, and Bases.

l The implementation of these changes will delete unnecessary Surveillance Requirements, clarify Action statements in a case when both Units are in i different operational MODES, and revise the Bases to reflect all above mentioned

changes.

9512210344 951218 PDR ADOCK 05000361 p PDR

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Subscribed on this /f day of 3ecem be e , 1995.

Respectfully submitted, SOUTHERN CALIFORNIA EDIS0N COMPANY By: u/ N Richard M. Rosenblum '

Vice President State of California County of San Diego j On /2//?/93 before me,3AAdA44 A.NCCAAT#,fy,744y personally Ngt e, appeared Richer.l N. ?^w 6lm , personally known to me ':r r , v. .J - .c.; ,

- ;; . .,ea,a .' r M!

'::t:ry :;f d...;;) to be the persorrM whose name M is/aae subscribed to the within instrument and acknowledgad to me that he/;k /;t.,y executed the same in his/M r/;nwi, authorized capacityfter), and that by his/h c/;;, ,7 signatureM on the instrument the personfs-), or the entity upon behalf of which the personft) acted, executed the instrument.

WITNESS my hand and official seal.

. CO # 79 Signature , h Notary Public - Colfornia E a ORANGE COUNTY

{ Mr Cornm. Emires MAR 31,1999 4

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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION Application of SOUTHERN CALIFORNIA EDISON COMPANY, H R . for a Class 103 Docket No. 50-362 License to Acquire, Possess, and Use a Utilization iacility as Part of Amendment Application Unit No. 3 of the San Onofre Nuclear No. 100 Generating Station SOUTHERN CALIFORNIA EDISON COMPANY, H E. pursuant to 10 CFR 50.90, hereby submit Amendment Application No. 100.

This amendment application consists of Proposed Technical Specification Change No. NPF-10-407, Supplement 1 to Facility Operating License NPF-15. Proposed Technical Specification Change No. NPF-15-407, Supplement 1 is a request to revise Technical Specification 3/4.7.5, " Control Room Emergency Air Cleanup System." The proposed change will delete Surveillance Requirements 4.7.5.c.1, 4.7.5.e.5, and revise Surveillance Requirement 4.7.5.b, the ACTION statement, and Bases.

The implementation of these changes will delete unnecessary Surveillance Requirements, clarify Action statements in a case when both Units are in different operational MODES, and revise the Bases to reflect all above mentioned changes.

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Subscribed on this /f day of 38Cem her , 1995.

i Respectfully submitted, )

SOUTHERN CALIFORNIA EDIS0N COMPANY l l

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By:

l ,u # l

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. 'm .

Richard M. Rosenblum ' I Vice President  !

State of California ,

of San Diego g4y /gdu c-County On /.1 //P/95 _

before me,3A46A&4 A. N'CAAN, personally appeared NicH4A.D M. Retubiw t personally known to me 'M r^r:d t; ;.;

a

- : i::f; ;' ;.ti:':: .., .. A..  ;) to be the perso @ whose name M is/. ace subscribed to the within instrument and acknowledged to me that he/,,,m/,,,4 executed the same in his/?.;,/ ...i1 authorized capacityN , and that by his/6, /.l.. . , signatureM on the instrument the personft), or the entity upon behalf of which the personfst acted, executed the instrument.

WITNESS my hand and official seal.

Signature d. CoM *1h2179 i g Notary Public - con % f I ORANGE COUNTY 1 My Comm. Ewes map

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I REVIEW AND APPROYAL OF OL/ POL PROPOSED CHANGE Revision  !

SAN ON0FRE NUCLEAR GENERATING S ION -- UNIT NO. .I PROPOSED CHANGE NO. N = /M/faW7, guppfgpygg / /

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1. Description N $Y Wlbb g l&

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Attached Inforination PRIPARED BY Md (/ h ' /(([$ /2[/g/gf.

Q Dare REvmED $ / .

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Plant Lic ing Nnager P '

4 '[95

[ Data U"

2. Onsite Review and Approval

_ Operations

_ Maintenance

_ Health Physics

_ Chemistry

_ Elect. Systems Eng.

_ Nuc. Systems Eng.

_ Power Gen.

_ Emerg, Preparedness _

_ Training N nager, Technical Vice President, Nucl. Gen.

3. EC&FS Review and Approval

_ Manager, NEDO

1. / ygg N b h ((( kg / 4/[pf

_ Nuclear / Mechanical

_ Electrical / Controls ,

_ Civil / Plant Design

_ Manager of Nuclear fuel

_ Nuc. Safety Analysis

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Manager of EC&FS j gjgg #

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4 Supervisor of NSG

5. Comuments _

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1 DESCRIPTION AND SAFETY ANALYSIS j OF PROPOSED CHANGE NPF-10/15-407, SUPPLEMENT 1 2

This is a request to revise Technical Specification'(TS) 3/4.7.5, " Control Room Emergency Air Cleanup System," and its associated Bases B 3/4.7.5.

Existina Specifications:

i Unit 2: See Attachment "A" Unit 3: See Attachment "B" Proposed Specifications:

Unit 2

See Attachment "C" Unit 3: See Attachment "D"

> Proposed:Under Technical! Specifications 7:Imor6vement?Proaram~(TSIP)'

a 1 Specificationso(not chanaed Der PCN-407):

Unit 72:"  ;;;See! Atta'chmenti"E":

Uniti:3: 7 ?SeefAttachment9"F" -

l Prono' sed Under Technical"Soecifications7Imorov'ementiProaram (TSIP)

Specifications:-(chanaed per PCN 407)t,

Unit

2i!  !:See; Attachment':"G" Unit 3:2 t See At tachment 1"H" l

Attachmentl"I""

1.TCalculation4M-00732125, " Relative:Humiditylat?Charcoa1 Beds 7(ME418/& ~

ME419),7no10ASiHeati.ng,."iDecember1995.

2.' ' Cal cul at'i on :M;0073;126,;':"EvaporatedTimeof4 Entrapped!MoisturelinME419;" .

2 December,n 1995l.:

SUMMARY

OF CHANGES i

i The proposed change will revise Technical Specification (TS) 3/4.7.5 " Control i

Room Emergency Air Cleanup System" and its associated Bases 83/4.7.5. This change will delete unnecessary Surveillance Requirements, clarify operator's

action in a case when both Units are in different operational MODES, and

rewrite the Bases to reflect all of the above mentioned changes.

The proposed changes include the deletion of SURVEILLANCE REQUIREMENTS for duct heaters, and the addition of the NOTE "Each Unit shall enter applicable ACTIONS separately" before the ACTION statement. The SURVEILLANCE REQUIREMENT 4.7.5.c.1 concerning the leakage through the system's diverting valves will be

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deleted from the SURVEILLANCE REQUIREMENTS. The purpose of these changes is I to accurately reflect San Onofre Units 2 and 3 current operating practice.

Background

Technical Specification 3/4.7.5 ensures the Control Room Emergency Air Cleanup System (CREACUS) is capable of providing an enclosed environment from which the plant can be operated following an uncontrolled release of radioactivity or toxic gas to the atmosphere. The system consists of one normal air conditioning unit, two emergency supply filtration trains, two normal exhaust fans, and one smoke removal fan. The outside air intake louvers for the control room are located at elevation 30 feet. The normal air conditioning unit is provided with a moderate efficiency filter. Each of the two redundant emergency filtration trains is equipped with an emergency ventilation unit and an emergency air conditioning unit (See Sketch A.)

The emergency ventilation unit consists of a prefilter, HEPA filter, heating coil, charcoal filter, and fan. The emergency air conditioning unit consists of a prefilter, HEPA filter upstream, charcoal filter, HEPA filter downstream, cooling coil, and fan.

Upon receipt of a control room isolation signal (CRIS), actuated by either a safety injection actuation signal (SIAS) or a normal supply air duct high radiation signal, the control room HVAC system is automatically shifted to the emergency mode of operation. Transfer to the emergency mode may also be initiated manually from the control room. Transfer to the emergency mode .

consists of automatically closing the outside air isolation dampers from the '

normal supply air handling unit and all exhaust isolation dampers. This also stops the control building supply and exhaust fans, and activates both trains A and B outside air isolation dampers to the emergency ventilation units.

Transfer to the emergency mode also includes starting the emergency air conditioning units, opening the outside air isolation damper to the emergency filtration trains, and starting the fans.

Thus, when actuated by a CRIS or SIAS signal, each emergency ventilation supply train fan draws outside air through HEPA filters and charcoal filters and discharges into the respective emergency recirculation air conditioning unit. Outside air, which is required to provide pressurization of the control room, is directed through both the emergency ventilation supply unit and the emergency recirculation air conditioning unit in each train. Dose calculations, as indicated in the Unit 2 and 3 UFSAR (Section 6.4.4.3.e and 6.5.1.3.a), only take credit for the HEPA filters and charcoal adsorbers of the emergency recirculation air conditioning unit. The emergency ventilation supply unit is only credited with pressurizing the control room to 1/8 inch water gauge positive pressure (minimum) to prevent unfiltered inleakage.

A toxic gas isolation signal (TGIS) automatically switches the control room HVAC system to the isolation mode. This mode is the same as the emergency mode except outside air is prevented from entering the control room and mixing with recirculated air. That is, the emergency ventilation supply fans are not started.

Should the control room fill with smoke, the control room normal HVAC system is shifted automatically to the smoke removal mode to clear the atmosphere.

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{oI 3 u-g ue6 NOTE: This sketch is provided to illustrate.the backgrsand information concerning Control Room Emergency Air Cleanup System.

i Operation of the smoke removal mode is not safety related and, therefore, the capability to shift to the control room isolation mode is unaffected by the smoke removal mode. The 100% capacity smoke removal fan is started, the smoke isolation damper mounted in the smoke exhaust duct is opened, and the recirculation damper is closed.

DESCRIPTION OF CHANGES The following are the proposed changes to Technical Specification 3/4.7.5

" Control Room Emergency Air Cleanup System":

1. The NOTE " Each Unit shall enter applicable ACTIONS separately" was inserted before the ACTION statement.

Discussion The Technical Specifications do not address the operational situation when the Units are in different operational MODES. Because of different REQUIRED ACTIONS some confusion could take place. For example, if Unit 2 is in MODE I and Unit 3 is in MODE 5, the Required Actions for each Unit are not only different but conflicting (See Sketch B.). Without this NOTE it may not be clear what ACTION should be taken.

Conclusions:

The proposed NOTE "Each Unit shall enter applicable ACTIONS separately" clarifies an operational situation when both Units are in different operational MODES.

2. The Action statement " Units 2 and 3 in MODE 5 or 6" was changed to

" Units 2 or 3 in MODE 5 or 6."

Discussion The wording of the current Action statement is in conflict with the proposed new Note (from 1 above) which requires each Unit to enter applicable ACTIONS separately. The statement " Units 2 and 3..."

prevents each Unit from entering the applicable ACTION separately.

Conclusion The proposed change to the Action statement concerning CREACUS inoperability in MODES 5 or 6 is editorial in nature, is made for consistency with the new proposed Note, and clarifies the existing Required Action.

3. SURVEILLANCE REQUIREMENT 4.7.5.b has been revised. The new SURVEILLANCE REQUIREMENT reads "Each control Room Emergency Air Cleanup System shall be demonstrated OPERABLE at least once per 31 days on a STAGGERED TEST BASIS by initiating, from the control room, flow through the HEPA ,

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l SKETCH B MODE 1 MODE 5 -

Unit Unit 2 3 i

C C R R E E A A >

C C U U S S Train A Train B One Train is Inoperable Restore the inoperable system to Restore the inoperable system to OPERABLE status within 7 days or OPERABLE status within 7 days or ,

, be in at least HOT STANDBY within initiate and maintain operation of i the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD the remaining OPERABLE control room

! SHUTDOWN within the following 30 emergency air cleanup system in the hours. recirculation mode.

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}_ NOTE: This sketch is provided to illustrate Proposed Change #1, "Each i unit shall enter applicable ACTIONS separately."  ;

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4 1____ _ . ., --

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filters and charcoal adsorbers and verifying that the system operates for at least M

::i=t= 21 hours2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br />."

Discussion The emergency ventilation units consist of a prefilter, HEPA filter, i heating coil, charcoal filter, and fan. Each emergency ventilation supply train fan draws outside air through HEPA filters and charcoal adsorbers and discharges into the respective emergency recirculation air conditioning handling unit. During a radioactive release, outside air which is required to provide pressurization of the control room is directed through both the emergency ventilation supply unit and the emergency recirculation air conditioning unit in each train.

Current SURVEILLANCE REQUIREMENT 4.7.5.b states: "Each control room

emergency air cleanup system shall be demonstrated OPERABLE at least once per 31 days on a STAGGERED TEST BASIS by initiating, from the control room, flow through the HEPA filters and charcoal adsorbers and

verifying that the system operates for at least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> with the heaters on."

Current Bases 3/4.7.5 states

" Cumulative operation of the system with the heaters on for at least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> over a 31 day period is sufficient j to reduce the buildup of moisture on the adsorbers and HEPA filters."

i The following Sections of the UFSAR provide information related to the need for the intake filters and the need to maintain proper relative humidity (RH) in the intake duct:

l . UFSAR, Unit 2 and Unit 3, Chapter 6 " Habitability Systems",

l Section 6.4.4.3.e and Section 6.5.1.3.a l . UFSAR, Unit 2 and 3, Chapter 6 " Habitability Systems", Section i 6.4.2.2.2

. UFSAR, Unit 2 and 3. Chapter 15, Appendix 158, Table 15B-5 l " Control Room Ventilation System Parameters."

Dose calculations, as indicated in the Unit 2 and 3 UFSAR (Section 6.4.4.3.e and 6.5.1.3.a), only take credit for the HEPA filters and charcoal adsorbers of the emergency recirculation air conditioning unit.

l The emergency ventilation supply unit charcoal adsorbers and HEPA filters are not credited for removing radioactivity. The unit's only required function is to pressurize the control room to 1/8 inch water gauge positive pressure (minimum) to prevent unfiltered inleakage.

FSAR, Chapter 6 " Habitability Systems", Section 6.4.2.2.2 specifies the j need to maintain the Relative Humidity of the incoming air to 70% or less as follows: "In order to maximize carbon adsorber efficiency, an

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electric heating coil is provided in the outside air filter unit to j lower the relative humidity of the incoming air to 70%, or less."

i l FSAR, Chapter 15, Appendix 158, Table 158-5." Control Room Emergency

Ventilation System Parameters" in comment "b" concerning intake cleanup j filter efficiency states "No credit is taken for this filter removing radioactivity when calculating control room infiltration doses.

2 However, a filter efficiency of 100% is assumed when evaluating the i filter as a direct whole body gamma source." l

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The current design outside air makeup rate is 2050 cfm. When this  !

4 outside air is mixed with the recirculating air from the control room  ;

recirculation unit, the RH in the recirculation unit (where the credited . i j charcoal and HEPA filters are installed) is well below 60% and meets the

requirement of 70% RH. Even if a 100% moisture condition was to exit 4 the makeup unit filter, the resultant relative humidity in the recirculation unit would be below 60%.

The basis for operating the system with the heaters on for at least 10

hours is to reduce the buildup of moisture on the filters. However, i this is not necessary, since (1) these filters are not credited for

! removing radioactivity, and (2) these filters are not required for '

. meeting the relative humidity. requirements at the filters which are 4

credited. An-epcrating time Of 15 minute: i: sufficient time to j initiate flew through the system, c t:blish and maintain the prcper i system parameters, and ensure the system operability. Fiftcen minute:

. is consistent with the CE Standard Technical Specifications, NUREC 0212, Rev. 3.

Ani eng i nee ri ng7ev'al uat P O wa siperformed ?whi chieval uatesithe; t ime

'requireditojevaporateineimoistureicontainedintthetairitrappedinsids t f the CREACUSxhousing[a 4 ductiworksinicommunicationiwithithe:charco'l' a i beds.l.Tolconservatwely} evaluate 6the evaporation:LtimesitMastassumed i allJmoisture condensed to'waterJand;wouldLneed{to.' be evaporated?by!the i monthly; surveillance runL s Alsohit' wasiconserlvativelyfassumedithatfall

, condensation willioccurionjtheiemergencyiairifconditi~oningiunitsbottom

, area. 4 Based (onlthesejand fotherJconservati.veiassumption.s4theltime; j requiredtoievaporateltrapped:moisturefairfisl1434thours6jForithe'

phrpose'of? conservatism,MtheftimeJthe!CREACUSLtrainjneedsitoioperate everyj31[daysonfaiSTAGGERED;TESTfBASISto7demonstrateLitlis;0PERABLE was; increased (;toi2l hours 4

} Conclusion

Based on (1) the emergency ventilation unit filters are not credited for removing radioactivity, and (2) the emergency ventilation unit heaters are not required to maintain RH below 70 % in the recirculation unit

(where the credited filters are installed), ' ands (3)]theWesultsfof i

engirieeringTevaldation, there is no need to Verify opefabilit9 'of~the j heaters ~by operating the system for 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />. TwoThours Fiftcen minute

is a sufficient time to initiate flow through the HEPA filters and e

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charcoal adsorbers, establish and maintain the proper system parameters, and ensure the system operability.

The proposed SURVEILLANCE REQUIREMENT 4.7.5.b will read:

" Each Control Room Emergency Air Cleanup System shall be demonstrated OPERABLE at least once per 31 days on a STAGGERED TEST BASIS by initiating, from the control room, flow through the HEPA filters and charcoal adsorbers and verifying that the system operates for at least 15 minutef2[ hours."

4. The text of SURVEILLANCE REQUIREMENT 4.7.5.c.1 has been deleted. The word " Deleted" will be placed under this SURVEILLANCE REQUIREMENT instead of its text.

Discussion The present version of SURVEILLANCE REQUIREMENT 4.7.5.c.1 reads:

" Verifying that with the system operating at a flow rate of 35485 cfm 10% for the air conditioning unit, and 2050 150 cfm for the ventilation unit and recirculating through the respective HEPA filters and charcoal adsorbers, leakage through the system diverting valves is less than or equal to 1% air conditioning unit and 1% ventilation unit when the system is tested by admitting cold 00P at the respective intake."

A typical control room emergency air cleanup system is integrated with the normal control room ventilation and air conditioning system. During normal operation, the ventilation flow path bypasses the emergency air cleanup system by " diverting" the flow around the charcoal adsorbers and HEPA filters. During the emergency condition, the diverting valves close and the air is forced to pass through the emergency air cleanup units.

The existing surveilience requirement to measure leakage past the

" diverting valve" is not applicable to San Onofre Units 2 and 3. There i are no diverting valves in the emergency air cleanup system. This statement originated in the Combustion Engineering Standardized Technical Specifications. The Combustion Engineering Standardized Technical Specifications in the SURVEILLANCE REQUIREMENT 4.7.7.c.1 specifies in brackets "For systems with diverting valves". Since San Onofre Units 2 and 3 are not equipped with diverting valves, this SURVEILLANCE REQUIREMENT should not be included in the Technical l Specification.  :

Conclusion Based on the above information the text of SURVEILLANCE REQUIREMENT 4.7.5.c.1 was deleted from the proposed Technical Specification and the word " Deleted" was placed under this SURVEILLANCE REQUIREMENT instead of 4

its text.

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5. SURVEILLANCE REQUIREMENT 4.7.5.e.5 " Verifying that the heaters dissipate 4.8 kw i 5% when tested in accordance with ANSI N510-1975 "  !

will be deleted. '

Discussion 4

Current SURVEILLANCE REQUIREMENT 4.7.5.e 5 states: "Each control room i emergency air cleanup system shall be demonstrated OPERABLE at least once per-18 months by verifying that the heaters dissipate 4.8 kw 5%

when tested in accordance with ANSI N510-1975."

Current Bases 3/4.7.5 states: " Cumulative operation of the system with the heaters on for at least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> over a 31 day period is sufficient to reduce the buildup of moisture on the adsorbers and HEPA filters."

As discussed in item 3 even if a 100% moisture condition was to exit the makeup unit's filter, the resultant relative humidity in the i recirculation unit (where the credited HEPA and charcoal filters are installed) would be below 60% when mixed with the return air from the main control room. Also, no credit is taken for the intake HEPA and charcoal filters removing radioactivity when calculating the control room infiltration dose. l 3

j Conclusion Based on the analysis of the resultant relative humidity there is no need to heat the emergency ventilation supply unit's incoming air.

Also, no credit is taken for the intake HEPA and charcoal filters removing radioactivity when calculating the control room infiltration

dose. Therefore, this SURVEILLANCE REQUIREMENT concerning emergency

) ventilation supply unit incoming air heaters should be deleted from this Technical Specification.

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6. Bases 3/4.7.5 were rewritten in a more detailed manner.

The current Bases 3/4.7.5 " Control Room Emergency Air Cleanup System" discusses the basis for this system: 1) the ambient air temperature does not exceed the allowable temperature for continuous duty rating for the equipment and instrumentation cooled by this system, and 2) the control room will remain habitable for operating personnel during and following all credible accident conditions. The OPERABILITY of this system is basea on limiting the radiation exposure to personnel occupying the control room to 5 rem. This limitation is consistent with the i requiremets of General Design Criteria 19 of Appendix A,10 CFR 50.

Also, the current Bases discusses the use of heaters to reduce the buildup of moisture on the charcoal adsorbers and HEPA filters.

The proposed Bases reflect all changes which are specified in this proposed Amendment. Also, description or operation requirements concerning heaters are removed from the proposed Bases.

Conclusion The proposed Bases are rewritten completely to match changes provided in this Amendment.

7.: i The" control i Room? Emergency Ai r i Cl e'anu~plSis tem: ai r cond i tioni ngl: un i t j a i r

'flowirateiis changed from:35;485Jcfm/to;35,705Lcfm. ?The:requiremeent~

for! ai r fl ow ;i s i modi fi ed R by di ed than ?14 toirefl ectj equ i pmen.ti

~

replacement.n Theispecified toleranceifor/ the airJflovrate remainst 110%. tThis: change 1will? affect} SR 4.7: 5;c;2 RSRf4 ~.. 7- 5?c.4;nSR1417.5.e[11 SRf4(7:5.f,?andSR:445.g3:

Safety Analysis The proposed change described above shall be deemed to involve a significant hazards consideration if there is a positive finding in any one of the following areas:

1. Will operation of the facility in accordance with this proposed change involve a significant increase in the probability or consequences of any accident previously evaluated?

Response: No The control room emergency air cleanup system provides a protected environment from which operators can control the plant following an uncontrolled release of radioactivity or toxic gas.

Proposed Change I will insert the NOTE before the ACTION statements. CREACUS consists of two redundant independent trains which are used for both units. This NOTE addresses the operational situation when each Unit is in a different operational MODE.

Assume, for example, Unit 2 is in MODE I and Unit 3 is in MODE 5.

4 If one CREACUS train is inoperable MODE 1 REQUIRED ACTIONS specify the following: " Restore the inoperable system to OPERABLE status l within 7 days or be in at least HOT STANDBY within next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />." MODE 5 REQUIRED ACTIONS in the same operational situation are different.

These actions require: " Restore the inoperable system to OPERABLE status in seven days or initiate and maintain operation of the remaining OPERABLE CREACUS in recirculation mode."

Because of different REQUIRED ACTIONS, some confusion could take i place regarding what Action the operator should perform first.

This NOTE clarifies that each unit enters the specified REQUIRED ACTION separately.

Proposed Change 2 will change the wording of the existing Action statement concerning one CREACUS train inoperability in MODES 5 or

6. This change will substitute the word and with the word or.

Without this change a conflict between the new proposed Note I and the proposed ACTION statement would exist. The existing wording of this statement would prevent each Unit from entering i applicable Actions separately as required by the new proposed l Note. '

l Proposed Change 3 changes SURVEILLANCE REQUIREMENT 4.7.5.b. The I new version of this SURVEILLANCE REQUIREMENT is "Each Control Room l Emergency Air Cleanup System shall be demonstrated OPERABLE at least once per 31 days on a STAGGERED TEST BASIS by initiating, from the control room, flow through the HEPA filters and charcoal adsorbers and verifying that the system operates for at least M  :

mhte 2 t hours. " Surveillance requirements concerning emergency. '

. ventilation ~aiF supply heaters are not required, so the operating i time is reduced to M minutes. 2; hours. The basis for operating the system with the heaters on for~at~least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> is to reduce the buildup of moisture on the filters. However, this is not necessary, since (1) these filters are not credited for removing  !

radioactivity, and (2) these filters are not required for meeting I the relative humidity requirements at the filters which are credited, and (3)la_n engineering (evaluat.ioniwasiperformedf wh.ich evaluates thestimeirequired to evaporate;the moisturetcontainediin the'~ air trapped!insideitheMCREACUS h.ousingiand'ductiwork,:in~

communication'with1the?charcoalibeds4 To conservatively.evalrate

.theLevaporation time, Lit;wasjassumedfallfmoisture' condensed;to~

wateriand wouldineed to be evaporated bytthe? monthly (surveillance

~

run. iAlso,:.it was'conserv'atively? assumed:that.all? condensation will occur on the: emergency;airiconditioning; unit 1 bottom 2 area.

, Based:onstheseland other? conservative::a'ssumptionsU thertime.

required to evaporatestrapped moisture: air.:isL1'34: hours.: For the purpose.of: conservatism,ytheltime'the:CREACUS train;needsLto

. operate every 311: days::;onia STAGGERED TESTJBASIS'to demonstrate 1:it l is0PERABLEwasincreased;to;21hoursL 4

An operating time of 15 minute: 2' hours is sufficient time to initiate flow through the system, establish and maintain the proper system parameters and ensure the system operability.

j Mf4cen minute; is consistent with the CE Standard Technice Specifications, NUREC 0212, Rev. 3.

Proposed Change 4 deletes the text of SURVEILLANCE REQUIREMENT , 4.7.5.c.1 and places the word " Deleted" under this SURVEILLANCE i REQUIREMENT instead of its text. Diverting valves do not exist in the SONGS Unit 2 and 3 control room emergency air cleanup system.

Proposed Change 5 deletes SURVEILLANCE REQUIREMENT 4.7.5.e.5 from this TS. Intake air duct heaters are not required to be used because calculations show relative humidity of the control room recirculation air flow after mixing with emergency ventilation supply air flow is below the required 70%. Also, credit is not

taken for intake HEPA and charcoal filters removing radioactivity when calculating the control room infiltration doses. l Therefore, this SURVEILLANCE REQUIREMENT which requires verification of each heater to dissipate 4.8 kw was deleted.

Proposed change 6 will rewrite Bases B3/4.7.5 to be more detailed.

A brief description of the control room emergency air cleanup system and functions of its major components will be included.

Also, all required changes will be made to incorporate the above described changes.

Pr'oposed:changei7 wil11changeTthelCREAC.USTairTc6ndition'i_nglun_i_t ,

fl owl ra te ? from ' 35,485: cfm ito ) 35,705f cfm h.lThe i re' qui remeent? fori a i r '

flowfisimodifiedL bytlessithanfl%, to$reflectiequipment" replacement. Thej specifiedstoleranceiforgthe air flowirateTremai~ns

• 10%

Therefore, the proposed change will not involve a significant increase in the probability or consequences of any accident previously evaluated.

2. Will operation of the facility in accordance with this proposed change create the possibility of a new or different kind of accident from any previously evaluated?

Response: No The six changes proposed herein do not reduce the reliability or performance of the Control Room Emergency Air Cleanup System. The revised Surveillance Requirements ensure the CREACUS will continue to perform its intended design functions. Therefore, the proposed change will not create the possibility of a new or different kind of accident from any accident previously evaluated.

3. Will operation of the facility in accordance with this proposed change involve a significant reduction in a margin of safety?

Response: No Operation of the facility in accordance with these changes will not be adversely affected as a result of the six changes proposed herein. These proposed changes include some changes in the APPLICABILITY and ACTION sections, deletion of unnecessary requirements from SURVEILLANCE REQUIREMENTS, and rewriting Bases in a more detailed, informative manner. As credit is not taken for intake air filters removing radioactivity the deletion of the intake air heaters from the SURVEILLANCE REQUIREMENTS will not change safety margins. None of these changes requires revision or recalculation of any CREACUS parameter or characteristics.

Operation of the CREACUS is unaffected by these changes.

Generally, this modification of the current TECHNICAL

- . .- - . _ . . - _ . . . _ . - - = .. . - - . -

SPECIFICATION and SURVEILLANCE REQUIREMENTS is made to clarify some existing requirements _and delete unnecessary ones.

Therefore, operation of the facility in accordance with this proposed change will not involve a significant reduction in a margin of safety.

Safety and Sionificant Hazards Determination Based on the above Safety Analysis, it is concluded that: (1) the proposed change does not constitute a significant hazards consideration as defined by 10 CFR 50.92: and (2) there is reasonable assurance that the health and safety of the public will not be endangered by the proposed change; and (3) this action will not result in a condition which significantly alters the impact of the station on the environment as described in the NRC Final Environmental Statement.  ;

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