Text

Fourth Ten-Year Interval Inservice Inspection (ISI) Program Request 4ISI-02
	ML15344A519
Person / Time
Site:	Columbia
Issue date:	12/10/2015
From:	Javorik A; Energy Northwest
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	GO2-15-157
	Download: ML15344A519 (6)
	v • d • e

Alex Javorik Vice President, Engineering P.O. Box 968, Mail Drop PE20 Richland, WA 99352-0968 Ph. 509-377-8555 F. 509-377-4317 aljavorik@energy-northwest.com December 10, 2015 GO2-15-157 10 CFR 50.55a U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

Subject:

COLUMBIA GENERATING STATION, DOCKET NO. 50-397; FOURTH TEN-YEAR INTERVAL INSERVICE INSPECTION (ISI) PROGRAM REQUEST 4ISI-02

Reference:

Code Case N-795, Alternative Requirements for BWR Class 1 System Leakage Test Pressure Following Repair/Replacement Activities, approved by the American Society of Mechanical Engineers (ASME) on September 17, 2010

Dear Sir or Madam:

Pursuant to 10 CFR 50.55a(z)(2), Energy Northwest hereby requests NRC approval of the following relief request for the fourth ten-year inservice inspection (ISI) program interval at Columbia Generating Station (Columbia) ending December 12, 2025. Energy Northwest has determined that compliance with certain inspection requirements of ASME Section XI would result in unnecessary hardship or unusual difficulty without a compensating increase in the level of quality and safety. The details of the 10 CFR 50.55a request are provided as .

Energy Northwest requests approval within one year of this submittal.

There are no new commitments made in this submittal. If you have any questions or require additional information, please contact Lisa Williams at 509-377-8148.

COLUMBIA GENERATING STATION, DOCKET NO. 50-397 FOURTH TEN-YEAR INTERVAL INSERVICE INSPECTION (ISi) PROGRAM REQUEST 41Sl-02 Page 2 of 2 Executed this l{L~ay ot/?ece.J-et', 20..L?

Respectfully, ~~~~-Z7 A. L. Javorik Vice President, Engineering

Attachment:

As Stated cc: NRC Region IV Administrator NRC NRR Project Manager NRC Sr. Resident Inspector - 988C CD Sonoda - BPN1399 (email)

WA Horin - Winston & Strawn RR Cowley-WDOH (email)

EFSECutc.wa.gov-- EFSEC (email)

FOURTH TEN-YEAR INTERVAL INSERVICE INSPECTION (ISI) PROGRAM REQUEST 4ISI-02 Page 1 of 4 10 CFR 50.55a Request Number 4ISI-02 Proposed Alternative In Accordance with 10 CFR 50.55a(z)(2)

Hardship or Unusual Difficulty without Compensating Increase in Level of Quality or Safety

1. ASME Code Component(s) Affected All American Society of Mechanical Engineers (ASME)Section III Class 1 system components excluding the reactor vessel

2. Applicable Code Edition and Addenda

The Columbia Generating Station (Columbia) Inservice Inspection (ISI) fourth ten-year interval ASME Section XI Code is the 2007 Edition through 2008 Addenda.

3. Applicable Code Requirement

The 2007 Edition with the 2008 Addenda references IWB-5220 SYSTEM LEAKAGE TEST, IWB-5221(a), which requires the system leakage test to be conducted at a pressure not less than the pressure corresponding to 100% rated reactor power (1020 psig for Columbia) on Class 1 components.

4. Reason for Request

Energy Northwest requests the approval to use an alternative to IWB-5221(a) following repair/replacement activities on Class 1 system components excluding the reactor vessel. System leakage tests following repair/replacement activities on Class 1 system components are required to be performed at 1,020 psig or higher at Columbia. The proposed alternative will allow performance of system leakage tests following repair/replacement activities at slightly reduced pressure based on ASME Code Case N-795 with test condition hold times of one hour for non-insulated components and eight hours for insulated components.

The use of Code Case N-795 following repair/replacement activities at Columbia would allow execution of system leakage tests and VT-2 visual examinations during normal plant startup conditions at low reactor power levels for some Class 1 repair/replacement activities located in containment. Existing plant procedures require containment entry with an accompanying drywell inspection which would allow performance of VT-2 visual examination during this drywell inspection at low power. This would result in reduced personnel exposure and avoid abnormal system lineups.

FOURTH TEN-YEAR INTERVAL INSERVICE INSPECTION (ISI) PROGRAM REQUEST 4ISI-02 Page 2 of 4 Performance of the VT-2 visual examinations at the pressure specified in IWB-5221(a) with the plant at high power levels would result in high dose rates. High dose rates pose personnel safety hazards that are contrary to As Low As Reasonably Achievable (ALARA) practices. Additionally, containment entry at high power levels would require the plant to de-inert containment for personnel entry.

Performance of the VT-2 visual examinations at the pressure specified in IWB-5221(a) while the plant is in a shutdown condition requires either re-performance of the refueling outage Table IWB-2500-1 Category B-P system leakage test (Reactor Pressure Vessel (RPV) Leakage Test) or a customized local pressurization system leakage test. Both of these alternatives require abnormal plant system alignments that result in challenges to the plant and personnel.

Thus, compliance with the IWB-5221(a) requirements results in additional plant challenges, delays, and increased dose without a compensating increase in the level of safety and quality as compared to tests performed at slightly reduced pressures with extended hold times.

5. Proposed Alternative and Basis for Use Energy Northwest is requesting approval for the use of ASME Code Case N-795, approved by ASME on September 17, 2010, as an alternative to the system leakage test pressure requirement of IWB-5221(a). The applicable portions of Code Case N-795 (Reference 1) are provided below:

Case N-795 Alternative Requirements for BWR Class 1 System Leakage Test Pressure Following Repair/Replacement ActivitiesSection XI, Division 1 Inquiry: What alternative to the pressure corresponding to 100% rated reactor power, of IWB-5221(a), may be used during a BWR Class 1 system leakage test following repair/replacement activities?

Reply: It is the opinion of the Committee that as an alternative to the pressure corresponding to 100% rated reactor pressure required by IWB-5221(a), the following requirements shall be met for a BWR Class 1 system leakage test, following repair/replacement activities.

(a) A system leakage test (IWB-5220) shall be conducted at a test pressure of at least 87% of the pressure required by IWB-5221(a).

FOURTH TEN-YEAR INTERVAL INSERVICE INSPECTION (ISI) PROGRAM REQUEST 4ISI-02 Page 3 of 4 (b) The system shall be maintained at this pressure during the required hold time and the performance of the VT-2 visual examination, except as provided by IWA-5245.

(c) This alternative test pressure may not be used to satisfy the requirements of Table IWB-2500-1, Category B-P.

(d) This alternative test pressure may not be used to satisfy pressure test requirements following repair/replacement activities on the reactor vessel.

In lieu of the test condition hold times specified in Code Case N-795 (e), Columbia proposes alternative test hold times of one hour for non-insulated components and eight hours for insulated components prior to performing the required VT-2 visual examination. These hold times exceed the hold times in Code Case N-795.

Code Case N-795 allows a reduction of 13% in the test pressure required by IWB-5221(a) with a required hold time >50% longer than that required by IWB-5000. The longer hold time at the lower permitted test pressure allows additional time for leakage to accumulate and be identified during the VT-2 examination.

Use of the ASME Code Case N-795 would allow Columbia to use normal plant procedures and system alignments at low power to meet the system leakage test requirements following repair/replacement activities and minimize plant risk and personnel exposure.

Based on the above discussion, Columbia has concluded that the use of Code Case N-795 with the proposed additional hold times as an alternate to the requirements of IWB-5221(a) provides an acceptable level of quality and safety. Columbia therefore requests the approval for the use of Code Case N-795 with the additional hold times as an alternate to the requirements of IWB-5221(a) for the Class 1 system leakage test following repair/replacement activities. All other ASME Section XI requirements, for which relief is not being specifically requested, if authorized by NRC staff, will remain applicable including third party review by the Authorized Inspection Agency.

6. Duration of Proposed Relief Alternative Relief is requested for the Fourth Inspection Interval, from the date of relief approval through the end of the Fourth Inspection Interval on December 12, 2025.

FOURTH TEN-YEAR INTERVAL INSERVICE INSPECTION (ISI) PROGRAM REQUEST 4ISI-02 Page 4 of 4

7. Precedent A similar 10 CFR 50.55a relief request was approved for Columbias third 10-year interval by NRC letter Columbia Generating Station - Relief Request 3ISI-12, Proposed Alternative using Code Case N-795 (TAC NO. MF0319), dated August 9, 2013 [ADAMS Accession No. ML13191AD054] (Reference 2)

8. References

1. ASME Section XI Code Case N-795, "Alternative Requirements for BWR Class 1 System Leakage Test Pressure Following Repair/Replacement Activities,Section XI, Division 1."

2. Letter, Michael T. Markley (NRC) to Mark E. Reddemann (Energy Northwest),

Columbia Generating Station - Relief Request 3ISI-12, Proposed Alternative using Code Case N-795 (TAC NO. MF0319), dated August 9, 2013