ML20217C619

Application for Amend to License DPR-22,changing Tech Specs 3/4.17.B, Control Room Emergency Filtration Sys. Change Would Eliminate Unnecessary in-place Testing of HEPA & Activated Charcoal Filters Based on Sys Operating Time

ML20217C619
Person / Time
Site:	Monticello
Issue date:	09/30/1999
From:	Day B NORTHERN STATES POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20217C623	List: ML20217C619 ML20217C632
References
NUDOCS 9910130300
Download: ML20217C619 (11)

Text

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Northern States Power company Monticello Nuclear Generating Plant 2807 West County Road 75 Monticello, MN 55362 September 30,1999 US Nuclear Regulatory Commission 10 CFR Part 50 Attn: Document Control Desk Section 50.90 Washington, DC 20555 j MONTICELLO NUCLEAR GENERATING PLANT Docket No. 50-263 License No. DPR-22  ;

License Amendment Request Dated September 30,1999 Testing Requirements for Control Room Emergency Filtration System Filters Attached is a license amendment request which proposes a change to the Technical Specifications, Appendix A of the Operating License for the Monticello Nuclear ,

Generating Plant. This request is submitted in accordance with the provisions of 10 l CFR Part 50, Section 50.90. l The proposed amendment changes Technical Specification 3/4.17.B, Control Room l Emergency Filtration System. The change establishes Technical Specification  ;

surveillance periodicity requirements consistent with industry and NRC guidelines for j the HEPA and activated charcoal filters in tha Control Room Emergency Filtration j System.  !

The proposed change would eliminate unnecessary in-place testing of the HEPA and )

activated charcoal filters based on system operating time, which is not required by the l applicable codes and standards, and causes unnecessary wear on the system. As l discussed in Exhibit A, industry and NRC guidelines require laboratory testing of l activated charcoal filters after 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of operation, but do not require in-place testing j after 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of operation unless the charcoal bed is disturbed during sample removal. Since the charcoal bed is not disturbed when the sample is retrieved, in-place

}fi testing is not required for the charcoal or HEPA filters based on system operating time. l Other periodic in-place testing requirements (e.g., every 18 months, following painting, etc.) are not changed. g) 00 J i Northern States Power Company, a Minnesota corporation, requests authorization for a \ j change to Appendix A of the Monticello Operating License as shown on the  !

attachments labeled Exhibit A, B, and C. Exhibit A contains a description of the proposed TS change, the repgopquesting the change, a Safety Evaluation, a 9910130300 990930 PDR ADOCK 05000263 P PDR

D:t:rmination of No Significant Hazards Consid: ration, and an Environmental Assessment. Exhibit B contains the current Technical Specification pages marked up with the proposed change. Exhibit C contains revised Monticello Technical Specification pages.

This letter contains no restricted or other defence information.

Please contact Doug Neve at (612)-295-1353 if you require further information related to this request.

' M By Byron D. py 9 Plant Manager Monticello Nuclear Generating Plant c: Regional Administrator-lll, NRC NRR Project Manager, NRC Sr. Resident inspector, NRC I State of Minnesota Attn: Steve Minn J Silberg, Esq.

Attachments: Exhibit A- Evaluation of Proposed Change to the Monticello Technical Specifications Exhibit B - Current Monticello Technical Specificatic7 Pages Marked Up With Proposed Change Exhibit C - Revised Monticello Technical Specification Pages ]

On this 30fday of$umpa , /999 before me a notary publicin and for said County, personally appeared Eric C. Sopkin, acting for Byron D. Day, Plant Manager, Monticello Nuclear Generating Plant, and being first duly sworn acknowledged that he is authorized to execute this document on behalf of Northern States Power Company, that he knows the contents thereof, and that to the best of his knowledge, information, and belief the statements made in it are true and that it is not interposed for delay.

m Marcus H. Voth h , ,:--- - : ^ : ::':: :: ^ ^ ^ ^ ^ ^: ^::: ^ ^ ^

j WWS H. WH  :

Notary Public - Minnesota I! ""

Wright County 1~~

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My Commission Expires January 31,2000 09r30/091140 AM JtICENSBTech Specst.A R'sEFTLARan doc i

EXHIBIT A  ;

Evaluation of Proposed Change to the Monticello Technical Specifications l License Amendment Request Dated September 30,1999  ;

Testing Requirements for Control Room Emergency Filtration System Filters Pursuant to 10 CFR Part 50, Section 50.90, Northern States Power Company hereby j l proposes the following change to Appendix A to Facility Operating License DPR-22,

" Technical Specifications" for Monticello Nuclear Generating Plant.

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Background

- Current Monticello Technical Specifications (TS) require in-place testing of Control Room Emergency Filtration Train (EFT) System HEPA and activated charcoal filters once per 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of system operation; or once per operating cycle (not to exceed 18 months), or following painting, fire, or chemical release while the system is operating that could contaminate the HEPA filters or charcoal adsorbers. Industry and NRC regulatory guidance does not require in-place testing of the HEPA and charcoal filters based on system operating time. Industry and NRC regulatory guidance requires l I

laboratory testing of charcoal filters based on system operating time; however, it is not l-necessary to perform in-place testing unless system integrity is affected in order to obtain the sample.

Proposed Change The following change to Appendix A, of the Monticello Technical Specifications is l proposed:

1. Technical Specification Section 3.17. Control Room Habitability, Specification .

3.17.B.2., Control Room Emergency Filtration System Performance Requirements, page 229w.

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a. Specification 3.17.B.2 states:

2. Performance Requirements

a. Pen' odic Requirements (1) The results of the in-place DOP tests at 1000 cfm (210%) shall show $ 1% DOP penetration on each individual HEPA filter and shall shov' S 0.05% DOPpenetration on the combined HEPA filters.

(2) The results ofin-place halogenated hydrocarbon tests at 1000 cfm ($ 10%) shall 1 show $ 0.05% penetration on the combined charcoal banks.

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Exhibit A (3) The results oflaboratory carbon sample analysis shall showS 0.4% methyliodide penetration when tested at 30 C and 95%

relative humidity.

b. - The system shall be shown to be operable with.

b. The Specification is proposed to be changed to re-title Specification 2.a, add an acceptance criteria for laboratory testing based on system operating time as Specification 2.b, and re-index the former Specification J 2.b as Specification 2.c. Thus, the Specification is proposed to be changed to state (additions are shown in bold; deletions are shown struck out):

2. Performance Requirements

a. Acceptance Criteria - Periodic Requirements (1) The results of the in-place DOP tests at 1000 cfm (210%) shall show $ 1% DOP penetration on each individual HEPA filter and shall show

$ 0.05% DOP penetration on the combined HEPA filters.

(2) The results ofin-place halogenated hydrocarbon tests at 1000 cfm (210%) shall l show $ 0.05% penetration on the combined l charcoal banks. [

1 (3) The results oflaboratory carbon sample analysis shall show S 0.4% methyliodide penetration when tested at 30" C and 95%

relative humidity

b. Acceptance Criteria -- System Operation Requirements The results oflaboratory carbon sample 1 analysis shall show $ 0.4% methyliodide penetration when tested at 30* C and 95%

relative humidity bc. The system shall be shown to be operable with...

2. Technical Specification Section 4.17. Control Room Habitability, Specification 4.17.B.2., Control Room Emergency Filtration System Performance Requirements, page 229w.

a. Specification 4.17.B.2 states:

The in-place performance testing of HEPA filter banks and charcoal adsorber banks shall be conducted in accordance with Sections 10 and 11 of ASME N510-1989 with exceptions described in Section 6.7 of the r

Page A-2

E :b ,

' Exhibit A l

l USAR. The carbon sample test for methyliodide shall be conducted in accordance with ASTM D 3803-1989.

a. At least once per 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of system operation; or once per operating cycle, but not to exceed 18 months, whichever occurs first; or following painting, l fire, or chemical release while the system is operating that could contaminate the HEPA filters or charcoal adsorbers, perform the following:

(1) In-place DOP test the HEPA fillerbanks.

(2) In-place test the charcoal adsorberbanks with 1 halogenated hydtvcarbon tracer.

I (3) Remove one carbon test canisterfrom the charcoaladsorber. Subject this sample to a laboratory analysis to verify methyliodide removal efficiency.

(4) Initiate from the control room 1000 cfm (+ 10%)

flow through both trains of the emergency filtration treatment system.

b. At least once per operating cycle, but not to exceed

.18 months, the following conditions shall be '

demonstrated...

- a. The Specification is proposed to be changed to eliminate the in-place test requirement based on system operating time from Specification 2.a, add new Specification 2.b to maintain the laboratory test requirement for the charcoal filters based on system operating time, and re-index the former Specification 2.b as Specification 2.c. Thus, the Specification is proposed to be changed to state (additions are shown in bold; deletions are shown struck out):

The in-place performance testing of HEPA filter banks and charcoal adsorber banks shall be conducted in accordance with Sections 10 and 11 of ASME N510-1989 with exceptions described in Section 6.7 of the USAR. The carbon sample test for methyliodide shall be conducted in accordance with ASTM D 3803-1989.

a. At least sme per 720 bcurs of sys!c." cpor2!!cn; cr once peroperating cycle, but not to exceed 18

^

months, whichever rcure f%!; or following painting, fire, or chemical release while the system is operating that could contaminate the HEPA filters or charcoal adsorbsrs, perform the following:

Page A-3 o

l Exhibit A l

1 (1) In-place DOP test the HEPA filterbanks. j (2) In-place test the charcoal adsorber banks with l halogenated hydrocarbon tracer. j (3) Remove one carbon test canister from the l charcoal adsorber. Subject this semple to a i laboratory analysis to verify meth,Iiodide ,

removal efficiency.

{

(4) Initiate from the control room 1000 cfm (+ 10%)

flow through both trains of the emergency filtration treatment system. l

b. At least once per 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of system operation, \

remove one carbon test canisterfrom the charcoal adsorber. Subject this sample to a laboratory analysis to verify methyliodide removal efficiency.

bc. At least once per operating cycle, but not to exceed 18 months, the following conditions shall be demonstrated...

~lt should be noted that the addition of Specifications 3/4.17.B.2.b results in the addition of new page 229ww.

Reasons for Change A change is proposed to Technical Specification Sections 3/4.17.B, " Control Room l Emergency Filtration System," to eliminate unnecessary in-place testing of the HEPA and charcoal filters based on system operating time, which is not required by the l

l applicable codes and standards, and causes unnecessary wear and tear on the systami In-place testing based on system operating time is also not required by regulatory guidance. As discussed below, the NRC staff previously commented to Monticello that the in-place testing was not necessary for the EFT System based on system operating time. Additionally, starting the system from the Control Room to verify flow is not required to be performed based on system operating time and this requirement is proposed to be eliminated.

Safety Evaluation System Function and Design Basis The function of the Control Room Ventilation-Emergency Filtration Train (CRV-EFT) system is to maintain the environment of the Main Control Room, thereby ensuring its habitability during normal and accident conditions. The CRV-EFT system is composed of two subsystems, the Control Room Ventilation (CRV) subsystem and the Emergency Filtration Train (EFT) subsystem. The function of the CRV portion of the system is to provide the Control Room and the first and second floors of the EFT building with Page A-4

s Exhibit A conditioned air to maintain acceptable temperature conditions under normal and emergency conditions. The EFT subsystem provides for manualisolation of the Control Room and the first and second floors of the EFT building from outside air during  :

a toxic chemical release.- During a hypothetical radiological accident, the EFT provides for manual or immediate automatic pressurization of the Control Room with filtered air to minimize the activity, and therefore the radiological dose, inside the Control Room, j The redundant air filtration units consist of the following components in series: a low  !

efficiency filter, an electric heating element, a High Efficiency Particulate Air (HEPA) I filter, two 2-inch charcoal adsorber beds, a HEPA filter, and a centrifugal fan. The  !

charcoal adsorber removes gaseous lodine, and the HEPA filters remove particulate matter. l The EFT system is designed to provide adequate radiation protection to permit access and occupancy of the Control Room under accident conditions without personnel receiving radiation exposures in excess of 5 rem whole body, or its equivalent to any part of the body, for the duration of the accident. Section 6.7 of the MNGP USAR

.(Reference 1) provides additional information on the CRV-EFT system.

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Technical Specification Change The proposed change would require only laboratory testing of the charcoal adsorber after 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of system operation in-place testing of the HEPA and charcoal filters, verifying system flow, and laboratory testing of charcoal adsorber would still be required once per operating cycle (not to exceed 18 months), or following painting, fire, or chemical release that could contaminate the HEPA filters or charcoal adsorbers.

Testing of the EFT System is governed by ASME Standard N510-1989," Testing of Nuclear Air Treatment Systems" (Reference 2). Table 1 of this standard lists tests and inspections with recommended frequencies. Table 1 of ASME N510-1989 requires only laboratory testing of charcoal adsorbers to be performed based on a system operating time of 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br />, in-place testing of HEPA filters and charcoal filters is required once per cycle and after filter replacement, and after major system modification or repair.

These requirements are maintained in the proposed change.

NRC Generic Letter (GL) 83-13, " Clarification of Surveillance Requirements for HEPA Filters and Charcoal Adsorber Units in Standard Technicel Specifications on ESF Cleanup Systems" (Reference 3), provides surveillance requirements for systems such as the Monticello EFT System. The requirements do not specify in-place testing of the HEPA and charcoal filters based on system operating time. Only the charcoal filters are required to be laboratory tested based on system operating time. Thus, the proposed change is consistent with NRC GL 83-13.

Regulatory Guide (RG) 1.52, " Design, Testing, and Maintenance Criteria for

/tmosphere Cleanup System Air Filtration and Adsorption Units of Light-Water-Cooled Nuclear Power Plants," Revision 2, March 1978 (Reference 4) discusses in-place test criteria wnich apply to the EFT System. For both HEPA and charcoal adsorber filters, Page A-5

F . ,.

Exhibit A l

1 the in-place test requirements are: (1) initially, (2) at least once per.18 months  ;

thereafter, and (3) following painting, fire, or chemical release in any ventilation zone l communicating with the system. The test criteria of RG 1.52 do not specify system l operating time as a criterion for performing the in-place testing. The proposed change is consistent with the in-place testing requirements for HEPA and charcoal adsorber

- filters.

Regulatory Guide 1.52 requires in-place testing of charcoal adsorber filters following removal of an adsorber sample forlaboratory 'esting if the integrity of the adsorber section is affected.- For the Monticello EFT System, the sample canisters are physically j separate from the adsorber trays so trays are unaffected by sample removal. Blank i plates are used to replace each removed sample cartridge, with the plate mechanically clamped against a sealing gasket._ Thus,'the system integrity is not violated by sample i cartridge removal, as confirmed by in-place freon testing following each sample cartridge removal which has consistently found no detectable bypass leakage.

Therefore, in-place testing of the charcoal adsorber filters is not required following sample removal.

As part of reviewing and approving Amendment 65 to the Monticello Technical Specifications, NRC letter to NSP dated April 4,1988 (Reference 5) commented that it is not required by the staff to perform in-place testing after 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of operation unless system integrity is violated in order to obtain the sample. NSP letter to NRC l dated July 5,1988 (Reference 6) replied that the requirement to perform in-place '

i testing was conservative and would be retained to be consistent with the existing .

requirements for the Standby Gas Treatment System. In the Safety Evaluation Report (SER) for A.nendment 65 forwarded by NRC letter to NSP dated May 30,1989 (Reference 7) the staff found the response acceptable "since the proposed TS is more conservative than was recommended in staff guidelines." Thus, the change proposed in this submittal is consistent with previous NRC staff comments and guidelines on in-

- place testing of HEPA and charcoal filters. The proposed change would supercede that i

portion of the previous SER (Reference 7).

In-place testing every 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of operation produces unnecessary wear on the EFT System, specifically the housing doors, hatches and threaded batch bolts, and door / hatch sealing gaskets, since all doors must be opened or removed for each in-  ;

place test to accommodate the visual examination required by ASME N510-1989 (Reference 2).

I No Significant Hazards Consideration:

The proposed amendment has been evaluated to determine whether it constitutes a significant hazards' consideration as required by 10 CFR Part 50, section 50.91 using standards provided in section 50.92. This analysis is provided below:

The' proposed amendment will not involve a significant increase in the probab!!ity or consequences of an accident previously evaluated.

I Page A-6 l

l

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,~,,7 ,

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p f7 - / ' Exhibit A -

i During;an accident, the Control Room Emergency Filtration System provides' filtered sir.

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sto pressuri:.e the Control Room to minimize the activity, and therefore the radiological

' dose, inside the Control Room.(Technical Specification surveillance requirements are J established in' order to ensure that the EFT System will perform its safety function

' during.an~ accident. The proposed amendment eliminates unnecessary testing which is not required to show that the filters are operable and which causes unnecessary wear --

a_nd tear on the system'.' The remaining surveillances adequately show that the system is operable and capable of performing its safety function, ' Dose to the public and the Co.ntrol Room operators are not affected by the proposed changei i_ .The proposed' Technical Specification change does not introduce new equipment - 1

- operating rnodes, nor does the proposed change alter existing system relationships.

1 L The proposed amendment does not introduce new failure modes.

LTherefore, the proposed amendment will not significantly increase the probability or the

~

consequences of an accident previously evaluated.

The proposed amendment will not create the possibility of a new or different kind of.

, accident from any accident previously analyzed.

The proposed Technical. Specification change does not introduce new equipment -

' operating modes, nor does_the proposed change alter existing system relationships.  !

1

The proposed amendment does not introduce new failure' modes. The proposed

, surveillance requirements are consistent with industry and regulatory guidance and

'show that the' system is capable of performing its safety function. System reliability is enhanced by the' proposed change b'y eliminating unnecessary wear on the system.

E

Therefore, the proposed amendment will not create the possibility _of a new or different

kind of accident from any accident previously evaluated.  ;

1The proposed amendment will not involve a significant reduction in the margin of

' safety.

The proposed. amendment ls within current industry and regulatory standards for testing afilters.- The proposed amendment maintains margins of safety.E Off-site and Control Room' dose as'sessments are not affected by the proposed amendment, since the o" ability,of the EFT System to perform its safety function is shown by the proposed isurveillance requirements The proposed change to the surveillance provides -

Jassurance that the system will perform at the filter efficiency used in the evaluation of -

the radiological consequ'ences of the postulated events.' Therefore, the proposed My

. amendment will not involve a significant reduction in the margin of safety.

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Page A-7

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Exhibit A t

Environmental Assessment Northem States Power has evaluated the proposed change and determined that:

a 1.' The change does not involve a significant hazards consideration.

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2. The change does not involve a significant change in the type or significant increase in the amounts of any eff'uent that may be released offsite, or

_3. The change does not involve a significant increase in individual or cumulative occupational radiation exposure.

Accordingly, the proposed change meets the eligibility criterion for categorical exclusion

-set forth in 10 CFR Part 51,'Section 51.22(b), and an environmental assessment of the proposed change is not required.

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l Page A I

Exhibit A References-

71. MNGP US4R, Section 6.7,'" Plant Engineered Safeguards, Main Control Room, Emergency Filtration Train Building and Technical Support Center Habitability,"

Revision 17.

2.'. ASME Standard N510-1989, " Testing of Nuclear Air Treatment Systems."

3. NRC GL 83-13, " Clarification of Surveillance Requirements for HEPA Filters and Charcoal Adsorber Units in Standard Technical Specifications on ESF Cleanup Systems,": dated March 2,1983.

4. Regulatory Guide (RG) 1.52,~ " Design, Testing, and Maintenance Criteria for Atmosphere Cleanup System Air Filtration and Adsorption Units of Light-Water-Cooled Nuclear Power Plants," Revision 2, March 1978.

5. NRC letter to NSP, Proposed Technical Specifications for the Monticello Nuclear f Generating Plant Control Room Ventilation System' per TMi Action Item lli.D.3.4 (TAC No. 56977)" dated April 4,1988.

c p 6.f NSP_ letter to NRC," Revision 4 to License Amendment request Dated April 3,1984,"

dated July 5,1988.

7. NRC letter to NSP, " Amendment No. 65 to Facility Operating License No. DPR-22:

(TAC No. 56977)," dated May 30, .1989.

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