L-2012-193, Concrete Containment Inservice Inspection Program, Exempt Tendon Inspection Relief Request No.7

Concrete Containment Inservice Inspection Program, Exempt Tendon Inspection Relief Request No.7

ML12174A175
Person / Time
Site:	Turkey Point
Issue date:	06/05/2012
From:	Kiley M Florida Power & Light Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-2012-193
Download: ML12174A175 (8)

Text

0 June 5, 2012 FPL. L-2012-193 POWERING TODAY. 10 CFR 50.55a EMPOWERING TOMORROW, U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Re: Turkey Point Unit 4 Docket No. 50-251 Concrete Containment Inservice Inspection Program Exempt Tendon Inspection Relief Request No.7 In accordance with 10 CFR 50.55a (a)(3)(i), Florida Power and Light Company (FPL), is requesting relief for Turkey Point Unit 4, from ASME Section Xl Code, 2001 Edition, with Addenda through 2003, Paragraph IWL-2521.1(c), which requires that each exempted tendon shall be examined in accordance with IWL-2524 and IWL-2525 to the extent that the end anchorages of the exempt tendon are accessible either during operation or at an outage.

The tendon caps located near and above the Turkey Point Unit 4 discharge piping for the main steam safety and atmospheric dump and the steam generator blowdown to atmosphere are considered inaccessible during unit operation as a result of safety concerns for inspection p*ersonnel. In accordance with IWL-2521.1 any inaccessible tendon is designated as exempt.

FPL is requesting relief from the requirement to perform examinations at the inaccessible end of the designated exempt tendons during the Turkey Point Unit 4 2012 Fall refueling outage.

FPL seeks approval to perform substitute tendon examinations for Turkey Point Unit 4, following the Turkey Point Unit 3 tendon surveillance activities during the summer of 2012, without having to demobilize any inspection equipment or personnel already onsite.

Examinations of substitute tendons will provide sufficient information to assess the performance of the post-tensioning system subject to similar environmental conditions and prestressing requirements. As such, FPL proposes to perform alternative examinations to those in IWL-2521.1 (c) which will provide an acceptable level of quality and safety.

The attached Relief Request No. 7 for Turkey Point Unit 4 is submitted pursuant to 10 CFR 50.55a (a)(3)(i), since the proposed alternative examinations provide an acceptable level of quality and safety.

A similar Relief Request for Turkey Point Units 3 and 4 was previously approved by the Nuclear Regulatory Commission on October 20,1999. (TAC Nos. MA5239 and MA5240).

Approval of the attached Relief Request No.7 is requested by September 2012 to allow for rescheduling tendon examinations, if required.

an FPL Group company

L-201 1-193 Page 2 Should there be any questions concerning this submittal, please contact Mr. Robert J.

Tomonto, Licensing Manager, at (3""* 246-7327.

Sincerely, Michael Kiley Vice President Turkey Point Nuclear Plant S1I Attachment cc: Regional Administrator, Region II, USNRC Senior Resident Ins-ector, USNRC, Turkey Point Plant

ATTACHMENT TO L-2012-193 FLORIDA POWER AND LIGHT TURKEY POINT UNIT 4 RELIEF REQUEST No. 7 EXEMPT TENDON INSPECTION

ATTACHMENT L-2012-193 EXEMPT TENDON INSPECTION RELIEF REQUEST No. 7 Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

1. ASME CODE COMPONENTS AFFECTED Code Class CC Tendon Anchorage Areas, which are located at Buttress #5, on the west side of Buttresses #4 and #6 and at the ring girder above the Main Steam and Feedwater platforms at Turkey Point Unit 4. Category L-B, Unbonded Post-Tensioning System, Item Numbers L2.30, L2.40, and L2.50.

Approximately 142 hoop tendons and 65 dome tendons on each unit have one end considered inaccessible due to personnel safety. Tendon caps located near and above the discharge piping for the main steam safety and atmospheric dump and the steam generator blowdown to atmosphere are considered inaccessible during unit operation as a result of safety concerns for inspection personnel as determined by plant safety Specific tendons are selected on a random basis to be inspected in accordance with IWL-2521 during each surveillance interval. For the 40th Surveillance (IWL) Interval for Turkey Point Unit 4, the following four randomly-selected tendons fall within the ira-cessible tendon anchorage areas listed above: 1D20, 1D23, 2D20, and 51H40.

2. ASME CODE EDITION AND ADDENDA ASME Section Xl, 2001 Edition with Addenda through 2003, Subsection IWL.

3. APPLICABLE CODE REQUIREMENT The inspection requirements for the tendons are provided in ASME Section XI, 2001 Edition with Addenda through 2003, Subsection IWL. Specifically, Section IWL-2521 and Table IWL-2500-1 require the tendons to be inspected under the provisions of Category L-B, Unbonded Post-Tensioning System, Item Numbers L2.30, L2.40, and L2.50, where:

L2.30, which requires anchorage hardware and surrounding concrete to be examined in accordance with IWL-2524, and receive a detailed visual examination in accordance with IWL-231 0(b) extending 2 feet from the edge of the bearing plate, L2.40, which requires the corrosion protection medium to be examined in accordance with IWL-2525, and L2.50, which requires the amount of free water be examined in accordance with IWL-2525.

Section IWL-2521.1 permits the exemption from a full inspection of tendon anchorage areas that are not accessible for examination because of safety or radiological hazards or because of structural obstructions.

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ATTACHMENT L-2012-193 EXEMPT TENDON INSPECTION RELIEF REQUEST No. 7 The following are the alternative inspection requirements for the exempt tendon anchorages:

" Paragraph 2521.1(c) requires that each exempted tendon be examined in accordance with IWL-2524 and IWL-2525 to the extent that the end anchorages of the exempt tendon are accessible either during operation or at an outage.

• IWL-2524 requires a visual examination of the tendon anchorage areas (anchorage hardware, including bearing plates, anchorheads, wedges, buttonheads, shims, and the concrete extending outward a distance of 2 feet from the edge of the bearing plate), and documentation of free water contained in the anchorage end cap as well as any which drains from the tendon during the examination process.

" IWL-2525 requires the collection of samples of the corrosion protection medium for laboratory analysis for reserve alkalinity, water content, and concentrations of water soluble chlorides, nitrates, and sulfides. In addition, IWL-2525 requires the collection of free water for laboratory analysis to determine pH level.

4. REASON FOR THE RELIEF REQUEST The tendon caps located near and above the Turkey Point Unit 4 discharge piping for the main steam safeties, atmospheric dumps and the steam generator blowdown to atmosphere are considered inaccessible during unit operation as a result of safety concerns for inspection personnel. Therefore, per IWL-2521.1, they are exempted.

Florida Power & Light Company (FPL) is requesting relief from the requirement to perform examinations at the inaccessible end of exempt tendons during the upcoming Turkey Point Unit 4 2012 Fall refueling outage. FPL seeks approval to perform substitute tendon examinations for Turkey Point Unit 4, following the Turkey Point Unit 3 tendon surveillance during the summer of 2012, without having to demobilize any inspection equipment or personnel already onsite.

The request will relieve FPL from the requirement to perform the examinations required by IWL-2524 and IWL-2525, (i.e., Table IWL-2500-1, Item Numbers L2.30, L2.40, and L2.50) at the inaccessible end of exempt tendons. Examinations at the other end of exempted tendons, accessible during plant operation, are not affected by this request.

FPL is requesting relief from a full inspection of tendon anchorage areas pursuant to Section IWL-2521.1(c) of ASME Section XI and 10 CFR 50.55a(a)(3)(i), by proposing alternative examinations that will provide an acceptable level of quality and safety.

The proposed alternative is to inspect two tendons as substitutes for each inaccessible tendon ends for the Turkey Point Unit 4 40th year surveillance.

In total, there are eight tendons selected for substitution of four exempt tendons that have been randomly selected. Dome tendons 1D34 and 1D35 have been selected as alternatives for 1D20; 1D42 and 1D<3 are alternates for 1D23; 2D01 and 2D09 are aiternates for 2D20; and 62H35 and 62H36 are alternatives for 51 H40.

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ATTACHMENT L-2012-193 EXEMPT TENDON INSPECTION RELIEF REQUEST No. 7

5. PROPOSED ALTERNATIVE Pursuant to 10 CFR 50.55a(a)(3)i, FPL proposes an alternative to the Code requirements of IWL-2521.1(c) for the exempt tendons outlined in Section 1:

1. The accessible end of exempt tendons shall be examined in accordance with IWL-2524 and IWL-2525.

2. For each exempt tendon, an accessible substitute tendon within the same environment shall be selected and examined in accordance with IWL-2524 and IWL-2525.

3. In addition, an accessible tendon located as close as possible to each exempt tendon shall be examined at both ends in accordance with IWL-2524 and IWL-2525.

6. BASIS FOR USE The main purpose for examinations of the tendon anchorage areas, corrosion protection medium and free water during an outage (IWL-2524 and IWL-2525) would be to look for signs of corrosion in the tendon anchorage components and to assess the condition of the corrosion prevention medium and the concrete. During scheduled tendon inspections, these examnations are performed at many randomly selected tendons, and only relative few tendons in the sample are expected to be considered exempted due to personnel safety concerns. Furthermore, as stated in Relief Request 20 for the First Ten Yaar Interval, iKis statistically probable that up to three tendons on each unit may be exempt in any inspection period based on the number of tendons in the inaccessible area versus accessible tendons. This represents only 15% of the total number of tendons likely to be examined. The population of tendons that are non-exempt, plus the alternative examinations listed above, provide sufficient information to assess the performance of the entire post tensioning system given that each tendon is subject to similar environmental conditions and prestressing requirements.

To date, no significant anomalies have been noted with respect to corrosion of the tendon wires, anchorage components, or the corrosion prevention medium, in the general tendon population. The areas considered inaccessible are not subject to any unique conditions and selecting substitute tendons as close as possible to the exempt tendons will provide equivalent information as to the condition of the tendon caps. Several tendons located in the exclusion zone above the main steam platforms were examined during past inspections. These tendons were accessed primarily during an extended outage in which both Units 3 and 4 were shut down for in excess of one year. The results of these inspections were consistent with the results of tendons inspected in other locations.

The 30h and 3 5 th year inspections were performed in accordance with the approved Relief Request No. 20, issued by the NRC on October 20, 1999. As noted below, the results of these inspections demonstrated that the tendons were in compliance with the IWL requirements.

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ATTACHMENT L-2012-193 EXEMPT TENDON INSPECTION RELIEF REQUEST No. 7 During the 30th Year Inspections, Unit 4 tendon 2D23 was randomly selected for inspection and subsequently determined to be exempt. Substitute tendons 2D5 and 2D6 were selected and examined for this exempt tendon. In addition, visual inspection of the accessible anchorage areas of tendon 2D23 was performed. The results of the 30th Year inspection demonstrated that the tendons met the applicable Section Xl requirements.

During the 35th Year Inspections, Unit 4 tendon 2D34 was randomly selected for inspection and subsequently determined to be exempt due to safety hazards as discussed in Sections 2 of this Relief Request. Unit 4 substitute tendons 2D07 and 2D08 were selected and examined for these exempt tendons. Visual inspections of the accessible anchorage area of tendon 2D34 met the applicable Section XI requirements. The results of the 35th Year inspection demonstrated that the tendons met the applicable Section XI requirements.

In the previously approved Relief Request 20, the Staff concluded that the licensee's alternative examination provides more stringent requirements than IWL requirements by providing examination of additional tendon anchorages exposed to a similar environment in close proximity to the randomly selected tendon that has been

(.-xempted due to safety concerns.

Based on the preceding information, the proposed alternative examinations will provide an acceptable level of quality and safety in lieu of the requirements of IWL-2521.1 (c). As stated above, this Relief Request is applicable for Turkey Point Unit 4 only.

7. DURATION OF PROPOSED ALTERNATIVE:

The duration of the proposed alternative will be for the 40th tendon inspections, for the 2 nd 10-Year Interval of the Concrete Containment Inservice Inspection Program, 12-1SI/IWL-PTN-3/4, for Turkey Point Unit 4.

8. PRECEDENTS Similar relief was requested by Florida Power and Light Company for Turkey Point Units 3 and 4 for the First Ten-Year interval per Relief Request 20. Relief was granted by the NRC pursuant to 10 CFR 50.55a(a)(3)(i) per Safety Evaluation dated October 20,1999, (TAC Nos. MA-5239 and MA 5240)

9. ATTACHMENTS TO RELIEF REQUEST 7 Figure 1 Partial site plan Figure 2 Photo depicting location of exempt tendon 4 of 5

ATTACHMENT L-2012-193 EXEMPT TENDON INSPECTION RELIEF REQUEST No. 7 Figure 1: Partial Site Plan. The area between Buttress 4 and 5 for Unit 4 are considered inaccessible when Unit 4 is online.

Figure 2: Photos depicting relation of main steam safety valve tailpipes, atmospheric dump valve arid the Unit 4 Containment t5 of 5