1CAN078207, Responds to 820429 Request for Addl Info Re 5-yr Reactor Bldg Tendon Surveillance Rept

Responds to 820429 Request for Addl Info Re 5-yr Reactor Bldg Tendon Surveillance Rept

ML20058H677
Person / Time
Site:	Arkansas Nuclear
Issue date:	07/27/1982
From:	John Marshall ARKANSAS POWER & LIGHT CO.
To:	Stolz J Office of Nuclear Reactor Regulation
References
1CAN078207, 1CAN78207, NUDOCS 8208090039
Download: ML20058H677 (4)

Text

ARKANSAS POWER & LIGHT COMPANY POST OFFICE BOX 551 LITTLE ROCK, ARKANSAS 72203 (501)371-4000 July 27, 1982 1CAN078207 Director of Nuclear Reactor Regulation ATTN: Mr. J. F. Stolz, Chief Operating Reactors Branch #4 Division of Licensing U. S. Nuclear Regalatory Commission Washington, D. C. 20555

Subject:

Arkansas Nuclear One - Unit 1 Docket No. 50-313 License No. DPR-51 Information Request on AP&L's "Five Year Reactor Building Tendon Surveillance Report for Arkansas Nuclear One - Unit 1" Gentlemen:

Your April 29. 1982, letter (1CNA048216) requested additional information within 90 days on the subject report. The information requested and our responses are as follows:

QUESTION 1:

The minimum average design values for the hoop, dome and vertical tendons.

RESPONSE 1:

The minimum avera'ge design values for each of the hoop, dome and vertical tendons are listed as follows:

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1. Hoop tendon: 1171 kips

2. Dome tendon: 1226 kips

3. Vertical tendon: 1275 kips QUESTION 2:

l The initial seating force of the hoop, dome and vertical tendons.

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Mr. J. F. Stolz ,

2 July 27, 1982 RESPONSE 2:

The initial seating force of the hoop, dome and vertical tendons which were surveyed during the 5th year tendon surveillance program are listed as follows:

Hoop Tendon No. Seating Force (kips) 21H16 1575 21H42 1633 21H50 1598 31H11 1586 31H35 1580 31H47 1592 32H14 1604 32H26 1575 32H40 1592 32H46 1598 Dome Ten" n No.

107 1598 1012 1598 2022 1592 2029 1616 302 1592 3D24 1592 Vertical Tendon No.

V-3 1598 V-26 1598 V-68 1633 V-84 1622 V-102 1575 QUESTION 3:

The acceptance criteria used for the tendon surveillances conducted at 1 and 3 years after the initial stru-tural integrity test.

RESPONSE 3:

The acceptance criteria used for the tendon surveillance conducted at one and three years after the initial strsctural integrity test are specified in Section-11.0 of Appendix A, " Reactor Building Tendon Surveillance Procedure (Operating Precedure No. 1304.91) as included in the one year and three year ANO Unit 1 Tendon Surveillance Reports. Section 11 reads as follows:

The Acceptance Criteria shall be defined as meeting the requirements of subsections 7.1.5, 9.1.1, 9.1.2, 9.1.4, 9.1.5, 9.2, 9.3 with the exception of neutralization number, and 9.4.

Mr. J. F. Stolz ,

3 July 27, 1982 i

These requirements are extracted from the procedures and listed below with the subsection number in parentheses for cross references.

1. (7.1.5) If both of the tendons adjacent to the deficient tendon contain less than three broken wires per tendon, the deficiency shall be considered to be unique and acceptable.

2. (9.1.1) If the normalized liftoff force is equal to or greater than the minimum design prestress level in the tendon, as stated in Figure 4, the readings shall be recorded and surveillance continued.

3. (9.1.2) If the normalized liftoff is less than the minimum design prestress level in the tenden, as stated in Figure 4, the adjacent tendons on each site of the defective tendon shall be checked for liftof values and these recorded on Data Sheet #3.

4. (9.1.4) If either or both of the normalized liftoff forces obtained from the two tendons adjacent to the defective tendons are less than the design prestress level in the tendons, as stated in Figure 4, abnormal degradation of the post tensioning system shall be assumed and reported to the Nuclear Regulatory Commission.

5. (9.1.5) A plot of the normalized average tendon wire force vs.

time shall be prepared for each surveillance tendon. This plot is illustrated in Figure 4. When a reasonable trend has been established, the force-time plot shall be extrapolated over the 40 year life of the plant. If the extrapolated curves for two or more tendons extend beyond the maximum or minimum design prestress levels, as stated in Figure 4, an engineering evaluation of possible degradation of the post tensioning system shall be made.

6. (9.2) Wire Tests Failure below the guaranteed ultimate tensile strength (11,780 lb.) of any of the wire samples tested in accordance with Section 7.3 shall be considered to be an indication of abnormal degradation of the post tensioning system, and shall be reported per Section 10.0 of this procedure.

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7. (9.3) Sheathing Filler Inspection l

The sheathing filler material shall be considered to be an acceptable provided that the results of the test performed on the samples fall within the following limits:

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. Mr. J. F. Stolz ,

4 July 27, 1982 Test Limi+1 Water Soluble Chloride Less than 10.0 ppm Water Soluble Nitrates Less than 10.0 ppm Water Soluble Sulfides Less than 10.0 ppm Water Content Less than 10% Dry Weight Neutralization No. Greater than 1 If the results of these tests fall outside of the specified limits, one extra sample from each end of the tendons in question shall be taken and tested. If similar results are obtained, the sheathing filler from which the unacceptable samples were taken shall be replaced. As stated in Section 5.1.3, the results of these tests shall be recorded on forms provided by the testing laboratory.

8. (9.4) Evaluation of Previous Surveillance Records The tendon surveillance record for each tendon shall be compared with previous records to determine if:

a) Additional wires have broken since the last inspection; b) The liftoff wire force for each tendon has changed significantly; c) A change in wire corrosion status or sheathing filler has occurred; or d) A significant change in yield or ultimate strength or elongation under load at ultimate strength has occurred.

If any of these conditions are present, a report shall be prepared indicating any reasons for the observed results and recommending any remedial action necessary.

Sincerely, 00hn R. Marshall Manager, Licensing JRM:DET:sl PM I