Text

Relief Request for Limited Coverage Examinations Performed in the Third 10-Year Inservice Inspection Interval
	ML16343B035
Person / Time
Site:	Columbia
Issue date:	12/07/2016
From:	Javorik A; Energy Northwest
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	GO2-16-149
	Download: ML16343B035 (60)
	v • d • e

Alex L. 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 10 CFR 50.55a December 7, 2016 GO2-16-149 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

Subject:

COLUMBIA GENERATING STATION, DOCKET NO. 50-397; RELIEF REQUESTS FOR LIMITED COVERAGE EXAMINATIONS PERFORMED IN THE THIRD 10-YEAR INSERVICE INSPECTION INTERVAL

Dear Sir or Madam:

Pursuant to 10 CR 50.55a(g)(5)(iii), Energy Northwest is submitting the enclosed requests for relief from the American Society of Mechanical Engineers (ASME) Code requirements which have been determined to be impractical to perform during the third 10-year Inservice Inspection (ISI) interval at Columbia Generating Station (Columbia).

The third 10-year interval commenced on December 13, 2005 and ended on December 12, 2015 using the 2001 Edition through the 2003 Addenda of the ASME Section XI Code. In addition, relevant ASME Code Cases N-460 and N-663, which were approved for use in Revisions 14 through 17 of Regulatory Guide 1.147, Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1, Table 1 were also used during this interval. There were no limitations or conditions identified for the use of these Code Cases. The specific relief requests are provided in Attachments 1 through 4 of this letter and are numbered 3ISI-16 to 3ISI-19, respectively.

There are no new commitments made in this submittal.

G02-16-149 Page 2 of 2 If you have any questions or require additional information, please contact Mr. R.M.

Garcia, Licensing Supervisor at 509-377-8463.

I declare under penalty of perjury that the foregoing is true and correct.

Executed this 7th day of ?Re 6"H7/if,2016.

Respectfully, A. L.

rik Vice President, Engineering Attachments: As stated cc:

NRC RIV Regional Administrator NRC NRA Project Manager NRC Sr. Resident Inspector-988C CD Sonoda - BPA 1399 (email)

WA Horin - Winston & Strawn

GO2-16-149 Page 1 of 16 Relief Request 3ISI-16

GO2-16-149 Page 2 of 16 Relief Request 3ISI-16 10 CFR 50.55a Request Number 3ISI-16 NDE Coverage Limitations on the RPV Bottom Head Welds

1. ASME Code Component(s) Affected

==

Description:==

Alternative Requirements to the Examination of Pressure Retaining Welds in the Reactor Pressure Vessel ASME Code Class:

Class 1 Examination Category:

B-A Item Number:

B1.21, B1.22 Components Affected:

Reactor Pressure Vessel (RPV) Bottom Head Welds (See Table 3ISI-16.1)

2. Applicable Code Edition and Addenda

The Columbia Generating Station (Columbia) Inservice Inspection (ISI) third ten-year interval ASME Section XI Code is the 2001 Edition through 2003 Addenda.

3. Applicable Code Requirement

ASME Section XI, Table IWB-2500-1, Examination Category B-A, Pressure Retaining Welds in Reactor Vessel:

Item B1.21 requires a volumetric examination of essentially 100% of the weld length of the bottom head circumferential welds in accordance with the examination requirements illustrated in Figure IWB-2500-3.

Item B1.22 requires a volumetric examination of essentially 100% of the weld length of the bottom head meridional welds in accordance with the examination requirements illustrated in Figure IWB-2500-3.

Code Case N-460 This Code Case states that when the entire examination volume or area cannot be examined due to interference by another component or part geometry, a reduction in examination coverage on any Class 1 or Class 2 weld may be accepted provided the reduction in coverage for that weld is less than 10%. The applicable examination records shall identify both the cause and percentage of reduced examination coverage.

4. Impracticality of Compliance

During ultrasonic examination of the RPV bottom head circumferential and meridional welds listed in Table 3ISI-16.1, greater than 90% coverage of the required examination volume could not be obtained. Examinations were performed utilizing a Performance Demonstration Initiative (PDI) Appendix VIII qualified procedure specific to RPV assembly welds.

GO2-16-149 Page 3 of 16 Relief Request 3ISI-16 Due to the geometric configuration of the components, effective volumetric examination could only be performed from outside the RPV bottom head circumferential and meridional welds. The 60° refracted longitudinal (RL) beam angle used in the axial and circumferential direction was not able to achieve greater than 90% code required volume as required by Code Case N-460. The RPV bottom head coverage limitations on the circumferential welds were due to interference from the bottom head penetrations. The RPV bottom head coverage limitations on the meridional welds were due to interference by the vessel support skirt (See Figure 3ISI-16.1 and 16.2a & b).

Radiography is not practical on these types of vessel weld configurations, which prevent placement of the film and exposure source. Drawings and scan plans from the Ultrasonic Testing (UT) reports are provided for reference and clarification.

5. Burden Caused by Compliance

To effectively perform any significant additional Code allowable ultrasonic examinations, modification and/or replacement of the component would be required.

6. Proposed Alternative and Basis for Use

No alternative examination is proposed at this time.

Energy Northwest has examined the welds identified in Table 3ISI-16.1 to the extent practical and determined that results are acceptable with no recordable indications.

These RPV welds are also subject to VT-2 visual examination during system pressure testing in accordance with the requirements of Examination Category B-P and successfully passed their VT-2 examinations.

Energy Northwest requests the proposed relief be authorized pursuant to 10 CFR 50.55a(g)(6)(i).

7. Duration of Proposed Alternative

Relief is requested for the third ten-year inspection interval of the Inservice Inspection Program for Columbia Generating Station.

GO2-16-149 Page 4 of 16 Relief Request 3ISI-16 Table 3ISI-16.1 Examination Category B-A Cat Item No Comp ID Item Description Material 1 and Product Form Material 2 and Product Form Examination Code Coverage Obtained Examination Limitations and Results B-A B1.21 DG Bottom Head Circumferential Weld Rolled Plate-SA533 Gr.B CL1 Rolled Plate-SA533 Gr.B CL1 19%

The examination was limited due to proximity of the CRD penetrations. No recordable indications.

B-A B1.21 DR Bottom Head Circumferential Weld Rolled Plate-SA533 Gr.B CL1 Rolled Plate-SA533 Gr.B CL1 19%

The examination was limited due to proximity of the CRD penetrations. No recordable indications.

B-A B1.22 DA Bottom Head Meridional Weld @

272° Rolled Plate-SA533 Gr.B CL1 Rolled Plate-SA533 Gr.B CL1 72%