NG-94-3575, Request for TS Change (RTS-267),replacing Instrument Setpoint W/Ref to Appropriate Citation in Offsite Dose Assessment Manual & Modifying Operability Requirement & Required Action for Inoperable Offgas Vent Stack RMs

Request for TS Change (RTS-267),replacing Instrument Setpoint W/Ref to Appropriate Citation in Offsite Dose Assessment Manual & Modifying Operability Requirement & Required Action for Inoperable Offgas Vent Stack RMs

ML20077A913
Person / Time
Site:	Duane Arnold
Issue date:	11/10/1994
From:	Franz J IES UTILITIES INC., (FORMERLY IOWA ELECTRIC LIGHT
To:	Russell W NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation
Shared Package
ML20077A917	List: ML20077A919 NG-94-3575, Request for TS Change (RTS-267),replacing Instrument Setpoint W/Ref to Appropriate Citation in Offsite Dose Assessment Manual & Modifying Operability Requirement & Required Action for Inoperable Offgas Vent Stack RMs
References
NG-94-3575, NUDOCS 9411280155
Download: ML20077A913 (12)

Text

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UTILITIES INC.

John F. Franz, Jr.

Vice President, Nuclear November 10,1994 NG-94-3575 Mr. William T. Russell, Director Oflice of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Attn: Document Control Desk Mail Station PI-137 Washington, DC 20555

Subject:

Duane Arnold linergy Center Docket No: 50-331 Op. License No: DPR-49 Request for Technical Specification Change (RTS-267) OfTgas Radiation Monitor

Reference:

N/A File: A- 117, D-l 1

Dear Mr. Russell:

In accordance with the Code of Federal Regulations, Title 10, Sections 50.90 and 50.59, IES Utilities Inc. hereby requests revision of the Operating License for the Duane Arnold Energy Center (DAEC).

The proposed change will replace the instrument setpoint with a reference to the appropriate citation in the OfTsite Dose Assessment Manual (ODAM), modify the operability requirement and the required action for inoperable OfTgas Vent Stack radiation monitors and modify the required action for inoperable Refuel Floor and Reactor Building Vent Shaft radiation monitors.

During recent maintenance activities, we discovered that the currently required action is excessively restrictive. The purpose of these monitors is to automatically secure primary containment venting when high radiation levels are detected in the ellluent during venting or purging operations. The proposed amendment will establish an appropriate requirement for equipment operability and actions to be taken when the equipment is out of service. The revision to the setpoint will assure compliance to the limit for ofTsite dose. Also, the proposed revision to Action 26 in TS Table 3.2 - A will make it consistent with the actual practice ofisolating secondary containment, which is more conservatise than current Technical Specifications (TS) requirements.

This application has been reviewed by the DAl:C Operations Committee and the DAEC Safety Committee Pursuant to the requirements of 10 CFR 50 91, a copy of this submittal, including the ,

analysis of no significant hazards consideration, is being forwarded to our appointed state oflicial l 941.1280155 94t110

. PDR ADOCK 05000331 i t, .P PDR l II '

General Othce + PO. Box 351

• Cedar Rapids. Iowa S2406

• 319/398-4411 An IES INDUSTRIES Company

Mr. William T. Russell NG-94-3575 November 10,1994 Page 2  :

We hereby request that the proposed amendment be approved with an effective date 90 days aller  !

issuance to allow adequate time for implementation.  !

No new commitments are made in this letter.

Should you have further questions regarding this matter, please contact this office. I This letter is true and accurate to the best of my knowledge and belief.

IES UTILITIES INC.  !

By John F. Franz Vice President, Nuclear M .

State ofIowa j (County) of Linn -

l Signed and sworn to before me on this day of I d(,[2 1 ,1994, f

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Attachments: 1. Evaluation of Change With Respect to 10 CFR 50.92

2. Proposed Change RTS-267 to the Duane Arnold Energy Center l Technical Specifications  ;

3. Environmental Consideration l

4. Safety Assessment cc: S. Catron L. Liu L. Root G. Kelly (NRC-NRR)

J. Martin (Region III)

NRC Resident Oflice S. Ilrown (State oflowa)

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4 RTS-267 Attachment I to

. NG-94-3575 Page 1 of 3 Evaluation of Change With_Regect to 10 CFR 50.92 ILackground The OfTgas Stack radiation monitors provide an isolation signal to the secondary containment isolation valves (Group III) based upon an indication ofincreased activity in the gaseous ellluent during normal and post accident venting or purging of primary containment. This isolation signal was added to satisfy the requirement of NUREG 0737, Item II.E.4.2(7), to provide automatic termination of radioactive releases during containment venting in the event that those releases exceed a predetermined setpoint.

While the NUREG simply required termination of the release, utilizing the DAEC Group 111 isolation logic was deemed an expedient method ofimplementing the requirement.

The instrumentation used for initiating the isolation is the OfTgas Stack radiation monitors. -

These monitors sample the gaseous ellluent and provide an indication of radioactivity.

The isolation setpoint is chosen based upon the limit for dose to a person outside the site boundary and is calculated in accordance with the OITsite Dose Assessment Manual (ODAM). The monitors are connected to a common sample line, however, and therefore -

any maintenance affecting this sample line renders both instruments inoperable.

In 1993, a revision to Technical Specification (TS) 3.2.A became efTective, which required these instruments to be operable at all times when in Modes 1,2 or 3 (Run, Start-up or .

Hot Shutdown). This new TS requirement has resulted in difTiculty in performing maintenance or calibrations on these instruments, or the sample line, because the required action is to isolate Secondary Containment and operate the Standby Gas Treatment System. This requirement is excessively restrictive since the necessity for the isolation is only postulated during containment venting or purging. When the containment vent and purge valves are closed, there is no need for an automatic isolation.

The proposed Action Statement 27 allows provision for opening the containment vent and purge valves with this trip fimetion inoperable, provided that administratie control is established for these valves. This administrative control would be consistent with that specified in TS 3.7.D.2.c footnote and is discussed in the revised TS Basis.

The proposed revision would allow the Offgas Vent Stack high radiation setpoint to be derived from the ODAM (new Note "k"), change the operability requirement to match the ftmetion (new Note "m") and would allow greater flexibility in maintenance by not requiring isolation of secondary containment.

1 Action Statement 26 currently requires that secondary containment integrity be established and the Standby Gas Treatment System be operated whenever the Refuel Floor Exhaust Duct or Reactor fluilding Exhaust Shafl liigh Radiation monitors are out of senice. The appropriate action is to isolate Secondary Containment and operate the Standby Gas

l 1

I

. l RTS-267 Attachment I to l NG-94-3575

. Page 2 of 3 Treatment System. This action appears to have been the intent and is the action currently taken at DAEC. The reason for isolating Secondary Containment is that an automatic isolation function is out of service.

The Surveillance Requirements are not proposed to be revised because they remain consistent with the ODAM.

IES Utilities Inc.. Docket.No. 50-331

- Duane Antold Energy Center. Linn County Iojva Date of Amendment Reques_t; November 10,1994 Description of Amendment Request; The proposed amendment revises DAEC TS Section 3.2. A to refer to the ODAM for the setpoint of the OfTgas Stack Radiation Monitor and makes the " Applicable Operating Mode" and the " Action" statements for these instruments consistent with the required function. The Action statement for the other instruments which initiate Secondary Containment isolation is also revised to be consistent with the current practice and with the function of those instmments The Basis is also revised to add further description of the function and requirements.

Ilasis for No Significant llazards Consideration Determination The Commission has provided standards (10 CFR 50.92(c)) for determining whether a significant hazards consideration exists. A proposed amendment to an operating license for a facility involves no significant hazards consideration if operation of the facility in accordance with the proposed amendment would not (1) involve a significant increase in the probability or consequences of an accident previously evaluated; (2) create the possibility of a new or difTerent kind of accident from any accident previously evaluated; or (3) involve a significant reduction in a margin of safety.

Afler reviewing the proposed request for TS change, we have concluded:

1) The proposed amendment will not involve a significant increase in the probability or consequences of an accident previously evaluated because the instruments will still be required to be operable to initiate an isolation at a setpoint which will assure that the offsite dose limits are preserved, as designed, or else administrative controls will be established for the venting of primary containment. Through either means, offsite releases will be maintained within the limits established in the ODAM. The change to the applicable operating mode simply will require that the instruments be operable when they are assumed to be operable in previously analyzed accidents. The change to the required action when the TS requirement cannot be met will assure that the flow

RTS-267 Attachment I to NG-94-3575 Page 3 of 3 path from containment is isolated or that positive control is established so that any ofTsite radioactive gaseous release is within the limits analyzed in the ODAM.

2) The proposed amendment will not create the possibility of a new or different kind of accident from any previously evaluated because the afTected instruments are inputs to the secondary containment isolation and the revised specification will assure that they are operable or adequately compensated when they are assumed to perform their function. The instruments initiate a secondary containment isolation in the event that high radiation levels are detected in the monitored emuent.

3) The proposed amendment will not involve a significant reduction in a margin of safety because the revised applicability statement will assure that the instruments are operable when they are required to perform their function. The proposed compensatory action allows administrative control of the isolation valves when the instruments are inoperable and it is necessary to continue venting. This allowance recognizes that venting is a controlled evolution and that operator action would be adequate to prevent excessive releases in the event of high radioactivity in the ofTgas piping. The revision to the setpoint will not afrect system operation, but will continue to assure that the gaseous ellluents released are within the limits specified in the ODAM.

In summary, the proposed changes do not change the probability or consequences of an accident previously evaluated, do not create the possibility for a new or different kind of accident and do not involve a reduction in the margin of safety.

Therefore, the proposed license amendment isjudged to involve no significant hazards consideration.

Lncal Public Document Room Location; Cedar Rapids Public Library,500 First Street SE, Cedar Rapids , Iowa 52401 Attor_ney for Licensee: Jack Newman, Kathleen 11. Shea, Newman, Ilouknight &

Edgar, PC,1615 L Street NW, Washington, DC 20036 l

l l

RTS-267 Attachment 2 to NG-94-3575 Page1ofI homsed Change RTS-267 to the Duane Arnold Energyfenter Technical Specifications The holders of ficense DPR-49 for the Duane Arnold Energy Center propose to amend Appendix A (Technical Specifications) to said license by revising certain pages as indicated on the attached sheets. The List of Affected Pages is given below.

List of Affected Pages 3.2-4 3.2-7 3.2-46 Summary of Changes; The following list of proposed changes is in the order that the changes appear in the Technical Specifications.

P. age Description of Changej 3.2-4 Revise the Trip Level Setting, Applicable Operating Mode and Action for the OfTgas Vent Stack radiation monitors to reference new Notes "k" and "m" and Action 27.

3.2-7 Add new Note "k", which describes the criteria for establishing the setpoint at which the monitors initiate isolation. Add new Note "m" which describes the plant conditions under which the isolation functions are required to be operable. Revise Action 26 to require isolation of secondary containment. Add new Action 27, which describes the actions to be taken in the event the minimum TS requirements cannot be met when in the applicable operating condition.

3.2-46 Revise the Basis to reflect the revisions to the TS.