U-600676, Requests Relief from Requirements of Reg Guide 1.97,Rev 3 Re post-accident Sampling Sys Capability to Sample Containment & Drywell Equipment/Floor Drain Sumps.Description & Justification Encl.Fsar Will Be Revised

Requests Relief from Requirements of Reg Guide 1.97,Rev 3 Re post-accident Sampling Sys Capability to Sample Containment & Drywell Equipment/Floor Drain Sumps.Description & Justification Encl.Fsar Will Be Revised

ML20212E671
Person / Time
Site:	Clinton
Issue date:	08/11/1986
From:	Spangenberg F ILLINOIS POWER CO.
To:	Butler W Office of Nuclear Reactor Regulation
References
RTR-REGGD-01.097, RTR-REGGD-1.097, TASK-2.B.3, TASK-TM U-600676, NUDOCS 8608130128
Download: ML20212E671 (5)

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U-600676 L30-86(08-11)-L P04-86(08-11)-L 1A.120

/LLINO/S POWER COMPANY IP CLINTON POWER STATION. P.o. BOX 678 CLINTON, ILLINOIS 61727 August 11, 1986 Docket No. 50-461 Director of Nuclear Reactor Regulation Attention: Dr. W. R. Butler, Director JWR Project Directorate No. 4 Division of BWR Licensing U. S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

Clinton Power Station (CPS)

Post Accident Sampling System Exception to Regulatory Guide 1.97, Rev. 3

Dear Dr. Butler:

IP Letter U-600525, dated May 5, 1986, provided the NRC Staff with a revised " Post Accident Sampling System (PASS) Evaluation Report." The purpose of this letter is to request NRC approval of an exception to the requirements of Regulatory Guide 1.97, Revision 3, relative to the PASS design capability to sample the CPS Containment and Drywell Equipment /

Floor Drain Sumps. The attachment to this letter provides a description of the requested change in Illinois Power's (IP) position relative to Criterion 1 of TMI Action Plan Item II.B.3 and the technical justification for the requested exception to Regulatory Guide 1.97, Revision 3, Table 2, Note 19.

As a result of the requested change to the PASS design capability, IP will revise the appropriate pages of the Final Safety Analysis Report (FSAR) in Amendment 39 after Fuel Load. The attachment describes the affected changes to the FSAR. CPS Technical Specifications are not impacted by this change.

If you should have any questions on this matter, please contact me.

Sincerely yours, 8608130128 860811 PDR ADOCK05000g1 F. A. Spangenberg A Managtr - Licensing & Safety TLR/bjg Attachment cc: B. L. Siegel, NRC Clinton Licensing Project Manager Mr. F. J. Witt, BWR Plant Systems Branch NRC Resident Office Regional Administrator, Region III, USNRC l Illinois Department of Nuclear Safety 085b I i i

Attachment to U- 600676 Clinton Power Station (CPS)

Post Accident Sampling System Containment /Drywell Sump Sampling Capability Exception to Regulatory Guide 1.97, Revision 3 Introduction The Post Accident Sampling System (PASS) Evaluation Report was originally transmitted to the Staff, via a letter dated April 19, 1985.

The original transmittal letter, additional information submitted by letter dated June 11, 1985, and Final Safety Analysis Report (FSAR)

Amendment 33 provided the basis for the Staff's evaluation against the 11 PASS acceptance criteria for compliance with the requirements of NUREG-0737, Item II.B.3. As a result of the Staff's review, Safety Evaluation Report, Supplement #5 (SSER #5), Section 9.3.5, issued January 1986, resolved License Condition No. 6.

By IP Letter U-600525, dated May 5, 1986, the Staff was provided with a revision to the PASS Evaluation Report. The Staff has indicated that revisions to the NRC's SSER #5 evaluation will be documented in SSER #6, accepting the revised CPS compliance to TMI Action Plan Item II.B.3 as noted in U-600525.

Recent testing on the PASS Containment and Drywell Sump Sample Pumps indicates that these sample pumps do not meet the PASS design criteria.

Problems associated with pump seal leakage and flow blockage in the current design result in the inability of these pumps to develop sufficient head to meet PASS sump sample flow requirements. These sump sample pump problems would require significant engineering, procurement and field installation work to resolve, which will not support the CPS Fuel Load schedule. As an alternative to modifying these sump sample pumps, it is IP's position that such PASS sampling capability is not required to fulfill the intent of the applicable regulatory documents.

Therefore, IP requests that the Staff grant CPS an exception to Regulatory Guide 1.97, Revision 3, by removing the Containment and Drywell Equipment / Floor Drain Sumps sampling capability as PASS-related plant components. The remainder of this position paper provides the NRC with IP's regulatory analysis and the associated technical justification for this change in the CPS PASS design.

Compliance with TMI Action Plan Item II.B.3 In IP Letter U-600525, referenced above, IP's position relative to NUREG-0737, Item II.B.3, Criterion 1, stated that the liquid samples routed to the PASS Sample Analysis Panel consist of the following:

1. Reactor water cleanup effluent (for normal plant operation)

2. Reactor coolant via a reactor vessel Jet Pump instrument line

3. Drywell Equipment Drain Sump

4. Containment Equipment Drain Sump

5. Drywell Floor Drain Sump

6. Containment Floor Drain Sump

7. Residual Heat Removal (RHR) pump 1A or IB effluent (Reactor coolant or Suppression Pool water).

Attachmant to U-600676 It is IP's position that deleting the PASS sump sample capability from the design (i.e., items 3 through 6 above) will not affect CPS compliance with Criterion 1 of II.B.3, since this criterion requires liquid samples of Reactor coolant, which is fulfilled by items 1, 2 and 7 above. As will be discussed later, these sample points are sufficient to meet PASS requirements under a wide range of postulated accident conditions. IP's position on all other II.B.3 criteria remains -

unaffected as a result of this design change. Provided the NRC Staff accepts this change in IP's position on II.B.3, Criterion 1, the Staff's SSER #5 evaluation on page 9-3 will require revision to delete reference to PASS " containment sump" sample capability.

Compliance with Regulatory Guide 1.97, Rev. 3 Regulatory Guide (RG) 1.97, Revision 3, entitled " Instrumentation.for Light-Water-Cooled Nuclear Power Plants to Assess Plant and Environs Conditions During and Following an Accident," dated May 1983, provides methods acceptable to the NRC Staff to ensure necessary and sufficient instrumentation exists for assessing plant and environmental conditions during and following an accident. 'Such instrumentation and assessment capability is required by 10CFR50, Appendix A, General Design Criteria 13, 19 and 64.

IP's compliance with the RG 1.97 requirements was provided in Letter U-0767, dated December 11, 1984, via a report entitled "Conformance to Regulatory Guide 1.97, Clinton Power Station Unit No. 1." In addition, IP letters dated October 17, December 3, and December 26, 1985 transmitted variances impacting RG 1.97 instrumentation at CPS. FSAR amendments were subsequently issued to incorporate the CPS compliance positions via FSAR Table 7.1-13.

Deletion of Containment and Drywell Sumps sample capability from PASS affects CPS compliance with RG 1.97, Rev. 3, Table 2, Note 19, relative to the Type E variable identified as " Accident Sampling Capability Primary Coolant and Sump." Note 19 states that an installed capability should be provided for obtaining such sump liquid samples. This was l

identified as CPS parameter E13 in IP submittal U-0767 noted above and

! in FSAR Table 7.1-13.

Parameter E13 is identified in RG 1.97 to assist in radioactive release

' assessment, verification and analysis. However, the need for sampling a particular sump should take into account the design of the plant in which it is installed. For accidents in which radioactive material would be in the CPS Drywell Floor Drain Sump, this sump will isolate and would eventually overflow to the Drywell floor, up over the Weirwall and into tne Suppression Pool. A Suppression Pool sample can therefore be used as a valid alternative to a Drywell Floor Drain Sump sample.

! Similar technical justifications can be developed for deleting the other Containment and Drywell sump samples. For example, all four sumps noted above isolate after a postulated Loss of Coolant Accident (LOCA). As such, sump pump-out to Radwaste is not allowed post-LOCA. Thus, a sump

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Atttchment to U-600676 sample will not contribute to release assessment and verification.

Reactor coolant liquid samples from the other locations provided in the PASS design at CPS, as well as the Containment and Drywell gas samples, provide more accurate release assessment and verification capabilities.

Reactor Core Damage Estimation IP Letter U-600069, dated June 11, 1985, submitted the CPS " Reactor Core Damage Estimation" procedure to the NRC. This procedure is used (reference CPS Emergency Plan Implementing Procedure [EPIP] EC-13) to provide an estimate of reactor core damage based on the PASS liquid and gas samples, as well as other plant parameters (e.g., Drywell radiation levels) for accident assessment purposes. The Staff has reviewed and approved EPIP EC-13 in CPS SSER #5, Section 9.3.5.

EPIP EC-13 core damage estimates do not utilize the PASS sump sample analysis results. As noted in the table in Attachment 2 of this procedure, sufficient sample points, most representative of core conditions during an accident, are available from the other liquid and gaseous samples taken by PASS. For the same reason, the sample information (i.e., location, time, etc.) which would be identified on Attachment 3 of EPIP EC-13 does not include the sumps. As a result of the requested exception to RG 1.97, the CPS core damage estimation procedure will remain unchanged.

FSAR Impact Analysis Provided the NRC Staff accepts IP's request for an exception to RG 1.97 (Table 2, Note 19), IP hereby commits to revise the CPS FSAR in Amendment 39 after Fuel Load, as follows:

• Subsection 9.' '___ - delete PASS liquid sample capability relative to it ms 3, 4, 5, and 6 (consistent with II.B.3 compliance change).

• Appendix D. Item II.B.3 - delete reference to Drywell and Containment sumps in the CPS response.

• Table 7.1 for parameter E13, delete reference to sump samples and add an additional note discussing the exception to RG 1.97 for this item.

A review of Subsection 14.2.12.3.7 regarding preoperational phase teeting of the Process Sampling system indicates no impact on these tests, since the sump sample capability is being deleted from the PASS design.

Other CPS Documentation Impact Analysis This CPS exception to RG 1.97 for the PASS was also reviewed against the

- following:

1. CPS Final Draft Technical Specifications (i.e., section 6.8.4.c) on Post Accident Sampling - no changes required.

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Attachm:nt to U-600676

2. CPS Emergency Plan, Rev. 5 - Subsection 3.2.12 will be revised to delete reference to the Drywell and Containment sumps during the next major update.

Conclusions -

The CPS requested exception to RG 1.97 (Table 2, Note 19) regarding deletion of PASS sump sample capabilities will not impact CPS compliance with the intent of NUREG-0737, Item II.B.3, CPS Technical Specifications, or accident assessment relative to core damage estimst"in. The remaining PASS Reactor coolant liquid sample capability fully complies with II.B.3 criteria. This sample capability further meets the intent of RG 1.97, Rev. 3, Table 2, Note 19, by providing for release assessment and verification through samples more representative of core conditions than the referenced sumps at CPS.

Appropriate changes to the CPS FSAR will be incorporated, as noted above, in Amendment 39 after Fuel Load.