ML20151S799

Proposed Tech Specs,Increasing Max Allowable MSIV Leakage from 11.5 Scfh to 30 Scfh Per Valve When Tested at 25 Psig, IAW SR 4.7.D.6

ML20151S799
Person / Time
Site:	Quad Cities
Issue date:	08/31/1998
From:	COMMONWEALTH EDISON CO.
To:
Shared Package
ML20151S797	List: ML20151S799 SVP-98-291, Application for Amends to Licenses DPR-29 & DPR-30, Increasing Max Allowable MSIV Leakage from 11.5 Scfh to 30 Scfh Per Valve When Tested at 25 Psig,Iaw SR 4.7.D.6
References
NUDOCS 9809090051
Download: ML20151S799 (6)

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ATTACllMENT B MARKED-UP PAGE FOR PROPOSED CIIANGE SVP-98-291 (Page 1 of 2)

REVISED PAGE Page Change

1. Page 3/4.7-7 93o9090051 900031 4 DR ADOCK 05

- i CONTAINMENT SYSTEMS PCIVs 3/4.7.D l

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3.7 - LIMITING CONDITIONS FOR OPERATION 4.7 - SURVElLLANCE REQUIREMENTS  !

2. With one or more reactor a. At least once per 31 days by 4 .

instrumentation line excess flow check verifying the continuity of the i'_ valves inoperable, operation may 3 explosive charge.

'. continua and the provisions of {

a Specification 3.0.C are not applicable, b. At least once per 18 months by provided that within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> either: removing at least one explosive

' squib from an explosive valve such

a. The inoperable valve is restored to that each explosive squib will be OPERABLE status, or tested at least once per 90 months, and initiating the removed

b. The instrument line is isolated and explosive squib (s). The the associated instrument is replacement charge for the declared . inoperable. explcded squib (s) shall be from the same manufactured ba'tch as the

Otherwise, be in at least HOT one fired or from another batch SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> which has been certified by having and in COLD SHUTDOWN within the at least one of that batch following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. successfully fired. No squib shall

remain in use beyond the expiration of its shelf-life or operating life, as

, applicable, i

6. At the frequency specified by the Primary Containment Leakage Rate Testing Program, verify leakage for any one main steam line isolation valve when tested at P,(25 psig) is s; .

. scfh.

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I QUAD CITnES - UNITS 1 & 2

3/4.7-7 Amendment Nos. 171 a ur i

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i ATTACIIMENT C  ;

EVALUATION OF SIGNIFICANT IIA 7sARDS CONSIDERATIONS l AND ENVIRONMENTAL ASSESSMENT APPLICABILITY REVIEW 1

SVP-98-291 l (Page 1 of 4) l l

Comed has evaluated this proposed amendment for Quad Cities Station Units 1 and 2 '

and determined that it involves no significant hazards consideration. According to 10 CFR 50.92(c), a proposed amendment to an operadng license involves no significant hazards consideration if operation of the facility in accordance with the proposed amendment would not:

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Invo!ve a significant increase in the probability of occurrence or consequences of an accident previously evaluated; ,

l Create the possibility of a new or different kind of accident from any accident i previously evaluated; or l Involve a significant reduction in a margin of safety.

Comed proposes to amend Appendix A, Technical Specifications, of Facility Operating l Licenses DPR-29 and DPR-30. The proposed amendment request increases the maximum allowable MSIV leakage rate specified in Technical Specification Surveillance Requirement 4.7.D.6, for a single valve, from 11.5 scfh to 30 scfh. The benefits realized from this proposed change are significant. A greater allowable MSIV leak rate will reduce the amount of unplanned MSIV maintenance, improving outage performance and reducing radiation exposure for plant personnel.

The proposed increase in the maximum allowable MSIV leakage rate is supported by a revision to the Quad Cities Station Units 1 and 2 control room radiological assessment.

The revised radiological assessment was submitted to the NRC on May 19,1997,and includes significant enhancements such as credit for suppression pool scrubbing, updated ,

iodine dose conversion factors, and allowance for higher burnup fuel designs. The report also clearly defines the design inputs, methodologies and assumptions used in calculating the control room and ofTsite dose levels following a postulated design basis accident.

The determination that the criteria set forth in 10 CFR 50.92 are met for this amendment request is indicated below:

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i ATTACIIMENT C .

EVALUATION OF SIGNIFICANT IIAZARDS CONSIDERATIONS  !

i AND ENVIRONMENTAL ASSESSMENT APPLICABILITY i REVIEW I SVP-98-291 l

(Page 2 of 4) i Does the change involve a significant increase in the probability or consequences of  !

an accident previously evaluated?

i The proposed change to Technical Specification Surveillance Requirement 4.7.D.6 increases the maximum allowable leakage rate for a single Main Steam isolation <

Valve (MSIV) from 11.5 scfh to 30 scfh. This change has no impact on the l automatic or manual closure features of the valve including automatic actuations and response times. Closme of the MSIVs is a postulated transient considered in the design basis of the plant. Since the proposed change does not impact the response characteristics of the MSIVs during a postulated transient condition, the change does not impact the probability of an accident previously evaluated.

I The change in allowable MSIV leakage has been evaluated to assess the impact on control room operator dose and offsite dose levels. The radiological assessment was performed with an updated radiological methodology that included significant l enhancements, such as credit for suppression pool scrubbing, updated iodine dose l conversion factors, and allowance for higher burnup fuel designs. Using this revised methodology, which is consistent with current regulatory requirements, the resulting dose levels from a postulated design basis accident continue to remain below the limits established in 10 CFR 50, Appendix A, General Design Criteria 19 (GDC-19) l and 10 CFR 100. Therefore, the proposed change does not involve a significant I increase in the consequences of an accident previously evaluated j Therefore this proposed amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated.

Does the change create the possibility of a new or different kind of accident from  !

any accident previously evaluated?

The safety function of the MSIVs is to provide a timely steam line isolation to mitigate the release of radioactive steam and limit reactor inventory loss under certain accident and transient conditions. The MSIVs are designed to automatically close whenever plaat conditions warrant a main steam line isolation. The proposed increase in allowable MSIV leakage does not impact the MSIV's ability to perform its underlying safety function, nor does the change involve any physical features of the valves and associated steam lines to create a new or different type of accident.

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r EVALUATION OF SIGNIFICANT IIAZARDS CONSIDERATIONS i

AND ENVIRONMENTAL ASSESSMENT APPLICABILITY REVIEW SVP-98-291 (Page 3 of 4)

Therefore, the proposed changes do not create the possibility of a new or different kind of accident from any previously evaluated.

Does the change involve a significant reduction in a margin of safety?

The proposed increase in allowable MSIV leakage represents a nominal increase in the release of radioactivity during a design basis event. The radiological assessment l

was performed with an updated radiological methodology that included significant enhancements, such as credit for suppression pool scrubbing, updated iodine dose conversion factois, and allowance for higher burnup fuel designs. Using this revised methodology, which is consistent with current regulatory requirements, the resulting dose levels from a postulated design basis accident cor.tinue to remain below the limits established in 10 CFR 50, Appendix A, GDC-19 and 10 CFR 100.

l Therefore, these changes do not involve a significant reduction in the margin of safety.

Therefore, based upon the above evaluation, Comed has concluded that these changes l involve no significant hazards consideration.

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ATTACIINIENT C EVALUATION OF SIGNIFICANT IIAZARDS CONSIDERATIONS AND ENVIRONNIENTAL ASSESShlENT APPLICABILITY '

REVIEW SVP-98-291 (Page 4 of 4)

Comed has evaluated this proposed operating license amendment request against the criteria for identification oflicensing and regulatory actions requiring environmental assessment in accordance with 10 CFR 51.21 Comed has determined that this proposed license amendment request meets the criteria for a catego-ical exclusion set forth in 10 CFR 51.22(c)(9) and as such, has determined that no irreversible consequences exist in accordance with 10 CFR 50.92(b). This detecmination is based on the fact that this change is being proposed as an amendment to a license issued pursuant to 10 CFR 50 that changes a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or that changes an inspection or a surveillance requirement, and the amendment meets the following specific criteria:

(i) the amendment involves no significant hazards consideration.

As demonstrated in Attachment C, this proposed amendment does not involve any significant hazards consideration.

(ii) there is no significant change in the types or significant increase in the amounts of any eflluent that may be released offsite.

As documented in Attachment C, there will be no change in the types or significant increase in the amounts of any eflluents released ofTsite. Both control room operator and offsite dose levels remain within the regulatory requirements.

j (iii) there is no significant increase in individual or cumulative occupational radiation j exposure.

l l The proposed changes will not result in changes in the operation or configuration l of the facility. There will be no change in the level of controls or methodology

used for processing of radioactive efiluents or handling of solid radioactive waste, nor will the proposal result in any change in the normal radiation levels within the plant. Therefore, there will be no significant increase in individual or cumulative occupational radiation exposure resulting from this change. Exposure is expected to decrease based on the projected decrease in MSIV maintenance.

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