ML19354D921

From kanterella
Jump to navigation Jump to search
Application for Amends to Licenses NPF-9 & NPF-17,changing Tech Spec 3/4.7.6, Control Area Ventilation Sys by Reducing Temps from 120 F to 90 F in Control Area
ML19354D921
Person / Time
Site: Mcguire, McGuire  Duke Energy icon.png
Issue date: 01/19/1990
From: Tucker H
DUKE POWER CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML19354D922 List:
References
NUDOCS 9001250009
Download: ML19354D921 (7)


Text

g -- - . ,

T:- - --

Dukeibun Cornpanh fl<i B, h her .

. , ,

  • TO Bax33198 - -

lice hesident .

Charlotte, NC 28242 ~ Nuclear hoduction -

(704)373-4531 i DUKEPOWER January 19 1990-U.S. Nuclear-Regulatory Commission Document Control Desk Washington, D.C. 20555.

Subject:

McGuire Nuclear _ Station, Units 1 and 2 Docket Nos. 50-369, and 50-370 Proposed Amendment to Technical Specification 3/4.7.6, Control AreaLVentilation System' Gentlement Pursuant to 10 CFR 50.90, please find attached proposed license amendments-to facility-operating' licenses NPF-9 and NPF-17 for McGuire Nuclear Station Units 1 and 2, respectively. The changes'in this amendment request are intended to make the McGuire Technical Specifications for the Control Area Ventilation system more conservative.

Attachment No. 1 provides n' hand marked-. copy of the proposed changes, and Attachment No. 2 provides:'a description.of the changes;.a justification'and-safety analysis for the change; and, a no significant hazards discussion.'

Pursuant to.10-CFR 50.91(b)(1), the appropriate North Carolina officialcis-also being provided a copy of this amendment request.

Should there be any questions, please contact- Steve LeRoy ist- (704) 373-6233.

Very truly yours,

  • cM k -the llal B. Tucker SEL506 Attachments J

xc: Mr. S.D. Ebneter, Regional Administrator U.S. Nuclear Regulatory Commission, Region II

.101 Marietta Street, NW, Suite 2900.

Atlanta, Georgia ~ 30323 I

Qb

~9001250009 900119 t

.hDR..ADOCK 05000369 PDC- \

w

P ILS. Nu'el*zr R:gulctory Commiczion -

Document Control Desk

-January 19, 1990  !

Page 2  ;

Mr.'Dayne Brown, Chief Radiation Protection Branch

  • Division of Facility Services '

Department of Iluman Resources-701.Barbour Drive .

Raleigh, N.C. .27603-2008 Mr. Darlt ilood I NRC Project Manager Office'of Nuclear Reactor Regulation <

U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Mr. P.K. Van Doorn s NRC Senior Resident Inspector McGuire Nuclear Station j b

~

. l 11.S. Nu*citar Regul0 tory Commiccion i Document Control Desk January 19 1990 Page 3 i

HAL B. TUCKER, being duly sworn, states that he is Vice President of Duke Power Company; that he is authorized on the part of said Company to sign and 1 file with the U.S. Nuclear Regulatory Commission this revision to the McGuire Nuclear Station License Nos. NPF-9-and NPF-17; and, that'all statements and matters set forth therein are true and correct to the best of his knowledge.

s

/ g r w ifal B. Tucker, Vice President Subscribed and sworn to before me this day.of- .

Ya v0 afy Public " ' ' J got """ H '

g s , k.L

, . . K*,

My Commission Expires: [.y 7 g g 7 , ,, 'g

&fi, T /$W 5Es "c* $ o "*)V$ 'i c55 p -

.............g$;r

'GC6%

ll8llll00; E

l 1

-i 1-l l

l 1

'V.S.-Nuc1her R:gulctory Commiccion Document Control Desk  ;

January 19, 1990-f Attachment No. 1 T6chnical Discussion, No Significant Hazards Analysis, and i Environmental Impact Analysis.

Description of Proposed Channes

This submittal proposes amendments to the McGuire Technical Spccifications

[ (TS) that would: ,

6 Change TS 3.7.6 to delete'the two asterisks and corresponding footnote related to an allowed outage time (A0T) extension of 21 days that was-added to the TS per amendment no. 95 for Unit 1 and no. 77 for Unit 2; 4 Change the TS Surveillance Requirement 4.7.6.a for_120 degrees-F to 90 degrees-Fi and, 6 Change the TS Surveillance Requirement 4.7.6.c.2'and 4.7.6.d for methyl iodide penetration from less than 1%, to less than 0.175%.

L Justification / Technical Discussion By letter dated May 12,_1989, the NRC staff; issued amendment nos. 95'and 77 '

to the McGuire facility Operating License NPF-9 and NPF-17 (TACS 65649/65650) to authorize a one time extension of the allowed outage time for the Control Room Area Ventilation Chilled Water-(VC/YC) system to provide for system modifications. This amendment-added two asterisks and a corresponding footnote that described-the requirements associated with the A0T. Subsequent 3'/, the modifications were completed, and the' footnote and a:.terisks are no longer applicable.

Currently, TS 4.6.7.a requires that control room temperature be maintained-less than or equal to 120 degrees-F. --The air conditioning portion of the VC/YC system is designed'to maintain the control room temperature at i approximately 75 degrees-F. The VC/YC system is designed to maintain ~a habitable atmosphere in the. control. room during plant operation,.-shutdown,

, and post accident conditions. -Control room temperature limits also ensure r l that safety related electronic equipment and controls can_ function properly. '

j While the TSs require the control room temperature to be maintained less than or equal to 120 degrees-F, McGuire maintains the control room temperature less than or equal to 90 degrees-F. McGuire has a procedure in' place that provides guidance to reduce and/or mitigate the effects of an increasing Control Room temperature. This temperature requirement change'is

  • is based on a history of certain safety related solid state electronic equipment located in cabinets in the control room complex, associated with safety systems control and engineered safety features control, behaving erratically when control room temperature increases above 90" degrees-F.

ll.S. Nuciter Rsgulatory Commission Document Control Desk January 19, 1990 Attachment'No. 1 The control room air temperature is verified as required per TS 4.7.6.a. and if the control room temperature rises above this limit, that train of the VC system is declart.d inoperable.

Therefore, we request the exist.ng temperature limit of 120 degrees-F be reduced to 90 degrees-F. This request to reduce the control room temperature requirement will provide a higher level of reliability in that it will further ensure that electronic equipment in the control room area will not be subject to failures or erratic behavior as a result of high temperatures.

The request to change the methyl iodide penetration requirement-of less<than i 1% to less than 0.175% resulted from Duke's development of the McGuire VC/YC  ;

system Design Basis-Specification. During this process, it.was determined =

that the Outside Air Pressure Filter Trains (OAPFT) that serve the control  !

room area are rated at a 99% decontamination efficiency. The-carbon beds-on the VC OAPFTs are tested for less than 1% methyl iodide penetration in 1 accordance with TS 4.7.6.c.2. However, NRC Regulatory Guide 1~.52, Rev. 2, 'l Table 2, March 1978,-indicates that for a 1% penetration, a decontamination j i

efficiency of 95% is assumed for methyl iodide-analysis. The analysis performed for McGuire assumes a decontamination efficiency of 99%.

Additionally, the carbon filter beds are four inches for which a 99%

decontamination efficiency and methyl iodide penetration of 0.175% are i appropriate in accordance with NRC Regulatory Guide 1.52, Table ~2. j

-l All McGuire radioiodine penetration and retention test reports performed by Nuclear Containment Systems (a vendor) for 0APFT A and B carbon samples were reviewed. The test reports gave the penetration for a two inch carbon bed -j rather than a four inch carbon bed. All tests indicated a percent '!

penetration of much less than 0.175% methyl' iodide, except-for the test of' sample no.85-703 dated January 1, 1985.- This test was: performed at 30 degrees-C and 95% Relative Humidity, and resulted in a 0.23% methyl' iodide ,

penetration and 99.77% decontamination efficiency. [All testing at 30 l degrees-C and 95% Relative Humidity was performed for. informational purposes i to prepare for the possibility of future required testing under these more- l stringent conditions.] This test of a two inch carbon bed sample would be '

the equivalent of a 0.05% methyl iodide penetration for a four inch carbon I bed sample. McGuire VC/YC system operability is established based.on 80 degrees-C and 70% relative humidity tests as-required:by NRC Regulatory i Guide 1.52 and ANSI N509-1976, Table 5-1. Test 5.b. All 80 degrees-C and 70% relative humidity tests resulted in methyl iodide penetration values of  ;

less than 0.175%. Therefore, because the McGuire analysis assumes a 99% t decontamination efficiency, the methyl iodide penetration requirement should  :

be changed to the more correct value of 0.175%.

Additionally, a dose assessment was performed assuming a 95% decontamination efficiency, as is implied by the existing TS 4.7.6, instead of 997. (license basis). The result was a control room thyroid dose of 52 Rem which is-greater than the 30 Rem allowed by Standard Review Plan 6.4. Therefore, a methyl iodide penetration of 0.175% should be used for the 99% '

decontamination officiency requirement.

i ll.S. Nuclair Regulatory Commicsion

~ Document Control Desk January 19, 1990 Attachment No. 1

,No Sihnificant Hazards Analysis Duke Power Compan'y has determined that this' amendment does not' involve a-l significant hazards ~ consideration. 10 CFR 50.92 states that a proposed-

!. amendment involves no'significant hazards considerations if operation in L accordance with the proposed amendment would not: 1 (1)-Involve a significant 1

l increase in the probability or consequences of an accident previously l: evaluated or,(2) Create the possibility"of.a new or different kind of accident previously evaluated; or., (3) Involve a significant reduction ~in the margin of safety.

Operation of the McGuire facility in accordance with the proposed amendment would not involve a significant increase in the probability or consequences of an accident previously evaluated. The deletion' of the footnote for: the VC/YC A0T is administrative in nature. The footnote is no longer applicable because the associated modifications to the VC/YC' system have been completed. The proposal to change the surveillance requirement temperature from 120 degrees-F to 90 degrees-F constitutes a conservative change to.

further limit control room air temperature as a result of documented failures of safety related electronic equipment-in the control-room when temperatures approach 90 degrees-F. McGuire.is currently using 90 degrees-F as the control room temperature limit; therefore, the change.will more accurately reflect an existing operating requirement. Operating under=this:

proposed change, the VC/YC system will continue to perform as designed to >

maintain proper temperature, cleanliness, and pressurization in this area during plant operation, shutdown, post accident conditions, and all feasible weather conditions. There will be no hardware or_ system modifications as a result of the proposed change. This change is more restrictive than the j existing TS requirement in that a more conservative value is being l introduced. The request to change the TS Surveillance Requirement for methyl iodide penetration from less-than 1%-to less than 0.175% is also more-restrictive and will further ensure filtration of control room air as required to maintain the control ~ room habitable during all phases _of operation. There will be no hardware or system modifications, or operational changes as a result of the new value.

Operation of the McGuire facility in accordance with the proposed amendment would not create the-possibility of a new or different kind of accident previously evaluated. As stated above, the change to delete the footnote is administrative in nature and in no way affects operation or control of the system. The other proposed changes involve the introduction of more restrictive values and'do not alter the operation of the. system nor involve l: any hardware changes to the system. Operation with these new values will further ensure the control room area is habitable during all phases of operation.

l l

C i

sa_m_._____m_.__.___-.__. _ _ _ _ _-_ _ _ - . - -

U.S. Nuc1cht R:gulctory Commicalcn Document Control Desk I

-January 19. 1990 l Attachment No. 1 Operation of the McGuire facility in accordance'with the proposed amendment would not involve a significant reduction in the margin if safety. In .

t addition to that stated above, the proposed changes will not increase'the >

types and amounts of radioactive effluents that may be released offsite, nor

-increase individual or occupational exposures. Under the~more restrictive changes proposed, the VC/YC TSs will continue to provide adequate . .

requirements and controls for maintaining the control room environment to ensure control room habitability during all' phases of operation.-

In conclusion, the proposed changes' constitute an administrative change, and' '

changes that introduce values more-restrictive than those in the existing TSs, therefore; Duke concludes that the' proposed changes contained in this.

amendment request do not involve a significant. hazards consideration as defined by 10 CFR 50.92.

Environmental Impact Analysis The. proposed technical specification amendment-has been reviewed against the criteria of 10 CFR 51.22 for. environmental considerations.- The proposed changes do not involve a significant hazards consideration,' nor increase the types and amounts of effluents that may be released offsite, nor increase j individual or cumulative occupational radiation exposures. Therefore, the I proposed technical specification changes meet the criteria given in 10'CFR 51.22 (c)(9) for a categorical exclusion from the requirement for an-Environmental Impace Statement.

l l

i I

i