ML20247K115
| ML20247K115 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 05/22/1989 |
| From: | Michael Ray TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 8906010216 | |
| Download: ML20247K115 (7) | |
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.e-TENNESSEE VALLEY AUTHORITY-CHATTANOOGA, TENNESSEE 37401 SN 1578 Lookout Place L
MAY 221989 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C.
20555 Gentlemen:
In the Matter of
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Docket Nos. 50-327 Tennessee Valley Authority
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50-328 SEQUOYAH NUCLEAR PLANT (SQN) UNITS 1 AND 2 - NRC INSPECTION REPORT NOS. 50-327/88-12, 50-328/88-12, 50-327'aR-13, AND 50-328/88-13 CORRECTION / CLARIFICATION OF ISSUE RESOLUTION The enclosures provide corrections and/or clarifications to statements contained in the subject inspection. reports.
The corrections / clarifications
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primarily provide additional detail required to ensure that the resolution of these issues or the details of' actions taken by TVA are clearly communicated and well understood.
If you have any questions, please telephone B. S. Schofield at (615) 843-6172.
Very truly yours, TENWESSEE VALLEY AUTHORITY Mp3 A
Manager, Nuc ar Licensing and Regulatory Affairs Enclosures cc: See page 2 8906010216 890522 I
PDR ADOCK 05000327 0
Q PDC f'l An Equal opportunity Employer
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,,j U.S. Nucle 4r Regulatory Commission MAY 221989 cc,(Enclosures):
Ms. S. C. Black,. Assistant Director for-Projects TVA Projects Division U.S. Nuclear Regulatory Commission One White Flint, North l
11555 Rockville Pike Rockvil1e, Maryland.20852-Mr. B. A. Wilson, Assistant Director
.for Inspection Programs TVA Projects Division U.S. Nuclear Regulatory Commission Region II 101 Marietta. Street, NW,. Suite 2900 Atlanta, Georgia 30323 Sequoyah Resident Inspector
.Sequoyah Nuclea^r Plant 2600 Igou Ferry Road Soddy Daisy,. Tennessee 37379
ENCLOSURE 1 CORRECTIONS / CLARIFICATIONS INSPECTION REPORT 50-327/88-12 AND 50-328/88-12 l '. Observation CEB-15, " Technical Adequacy of Miscellaneous Structural Steel" l
Refer to page A-8 of the report.
The fourth sentence of the first paragraph states, " Inspection Report 87-64 identified that TVA had increased their sample size to review 38 additional calculations and also planned to select 60 equipment support calculations.for review to determine whether the appropriate vendor loads were used in the design."
The sentence should be revised to read, " Inspection Report 87-64 identified that TVA had increased their sample size to include the regeneration of 38 additional calculations that were not retrievable and also planned to select 60 additional equipment support calculations for review to cetermine whether the appropriate vendor loads were used in the design."
The second paragraph, second sentence of the response, states, "TVA used design criteria SQN-DC-V-1.3.3.1, which is compatible with the FSAR loading combinations and allowable stresses." This statement should be revised to read, "TVA used design criteria SQN-DC-V-1.3.3.1, which is compatible with the NRC Standard Review Plan (SRP) loading combinations-and allowable stresses." -The differences between the Final Safety Analysis Report (FSAR) loading combinations and allowable stresses and the SRP loading combinations and allowable stresses were previously defined in TVA's October 21, 1987, letter to NRC.
In the second paragraph, fourth sentence of the report, reference to condition adverse to quality report (CAQR) SQP8702109 should be revised to SQP870210.
2.
Observation CEB-16, " Conduit and HVAC Duct Support Calculations" Refer to page A-ll of the report.
Item (b) in the second sentence on the page states, "(b) an absolute-sum combination of the loads from all three earthquake components..." and should be revised to read, "(b) an absolute-sum combination of the loads from all three earthquake components was used for most problems." Several supports could not be qualified by using all three components combined absolutely.
For those supports, the absolute-sum combination of the vertical and the worst-case horizontal earthquake component was used, which is in accordance with design criteria SQN-DC-V-13.10.
Item (b) in the third sentence on the page states, "(b) the absolute-sum combination of the loads from the vertical and one horizontal earthquake components..." and should be revised to read, "(b) the absolute-sum combination of the loads from the vertical and the worst-case component of horizontal earthquake..."
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Refer to page A-12 of the report.
The last paragraph should be revised to clarify that one rod hanger was replaced with a rigid support (2-370-12875) under engineering change notice (ECN) L5599, field change request (FCR) 4636, and workplan 12186.
The other rod hanger is scheduled to be replaced under ECN 7071, Category D, FCR 4753.
This replacement was scheduled and determined not to be needed before SQN unit 2 restart.
The last sentence of the last paragraph of observation CEB-16 (page A-13) should be revised to state tha+, although the staff considers the issue related to the conduits and opports closed, TVA will reevaluate, as a postrestart corrective action item, the conduits at these two supports using seismic loads based on 5 percent damped ARS.
The need for additional samples will be based upon the results of this reevaluation.
3.
Deficiency D4.2-1, "ERCH Pumping Station Access Cells" Refer to page C-2 of the report.
In the second paragraph of this item, it should be noted that the design calculation did not predict that shrinkage will occur in the interior concrete fill.
Inspection of the cells determined that shrinkage had occurred; however, the extent or location was not documented.
This was noted in'the calculations.
In the second paragraph, fourth sentence, the reference to TVA design criteria SQN-DC-V-104.5 should be revised to SQN-DC-V-1.4.5.
4.
Deficiency D4.2-3, " Vertical Response Spectra of the Steel Containment Vessel" Refer to page C-4 of the report.
The third sentence states, "As part of the resolution of this issue, TVA identified two additional structures where the newly generated vertical response spectra exceeded the original response spectra." The sentence should be revised to read, "As part of the resolution of this issue, TVA identified two additional structures where the recalculated vertical acceleration response spectra using an interval of integration of 0.005 second exceeded the original design basis vertical spectra over a narrow frequency range at the fundamental vertical frequency of the building."
5.
Deficiency D4.3-7, " Vertical Seismic Load on Auxiliary Building Roof Truss" Refer to page C-5 of the report for this deficiency item.
The third sentence on page C-6 states, "The new vertical floor response spectra exceeded the original vertical floor response spectra." This statement is not correct in that the recalculated vertical response spectra exceeded the original over only a limited frequency range, as clarified in TVA's March 2, 1988, letter to NRC.
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ENCLOSURE 2 CORRECTIONS / CLARIFICATIONS-INSPECTION REPORT 50-327/88-13 AND 50-328/88-13 1.
Refer to'section 3.0,-page 4, of the report.
In the third paragraph, the term " walls" should be replaced with " wall groups" in the second, third, fourth,'and sixth sentences.
2.
Deficiency D4.3-4, " Load Combination for Concrete Slab" Refer'to page A4-5 of the report.
The fourth and fifth paragraphs discuss resolution of the generic implications of this deficiency and the live load reconciliation and reinforcing bar cut programs.
The following comments are provided as clarification.
TVA drawing 41N704-1 provides the live load data used for the original design of concrete slabs.
To ensure that incorrect selection of the controlling load combinations did not occur because of the use of incorrect live loads, TVA reviewed the original / existing calculations for all the floor areas identified on drawing 41N704-1 before' restart of SQN unit 2 except for six areas that were previously_ evaluated as part of the prerestart work for the live load reconciliation and reinforcing bar cut programs. This review verified that no further inconsistencies existed in the use of the live load specified on drawing 41N704-1.
Therefore, this should resolve the generic implications'of this deficiency for the original / existing design.
The live load. reconciliation and reinforcing bar cut programs evaluate the as-built concrete slabs.
The allowable live loads determined by these programs will verify or supersede the original design live loads shown by
' drawing 41N704-1 As approved in a letter from NRC to TVA dated March 11, 1988, " Preliminary Safety Evaluations on the Tennessee Valley Authority Employee Concern Element Reports," these evaluations are to be done in accordance-with the ultimate strength method as_specified in TVA design criteria SQN-DC-V-1.3.3.1.
3.
Deficiency 04.3-5, " Shear Calculations for Slabs and Walls" Refer to page A4-6 of the report.
The terms " structural elements" and
" elements" in the second, third, and'last paragraphs should be revised to
" critical sections / structural elements" and " critical sections / elements, respectively." This revision is necessary because 294 separate structural elements (walls, slabs, beams, and columns) were not included in the review.
For example, more than one critical section may have been from the same slab.
For this reason, the term " critical section/ element" was used in TVA's December 29, 1987, letter to NRC, which provided a response to this deficiency.
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' The reference to the "ACI-318-63 Code" requirements in the first sentence of the last paragraph to this section should be revised to the " applicable.
i code requirements." The-shear calculations and allowable stresses are in-accordance with ACI'318-63, ACI 359, ACI 318-71, or the Structural Engineers Association of California code (shear walls), depending upon the.
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particular building or feature as specified in the FSAR.
4.
Deficiency D4.3-9, " Masonry Block Hall Evaluation for Bulletin 80-11" i.
Refer to page A4-12 of the report.
In the first paragraph, the-first
~ sentence states, "TVA performed calculations on nine worst case reinforced concrete block walls =to show that they meet the NRC criteria for extreme environmental and abnormal load conditions " The sentence should be revised to read, "TVA performed calculations on nine worst-case reinforced concrete block wall groups to show that they meet the NRC criteria for extreme environmental and abnormal: load conditions." Additionally, the term " wall groups" should be used instead of " walls" in the first and' second sentences of the second paragraph.
The first sentence in the third paragraph states, ".In addition.to these calculations, nine other reinforced masonry walls with openings were selected by TVA in.the auxiliary / control building for reevaluation in accordance with the NRC criteria." The sentence should be revised to read,."In-addition to these calculations, nine other reinforced masonry walls with critical openings were selecced by TVA in the auxiliary / control building for reevaluation in accordance with NRC criteria."
In the fourth paragraph, the first sentence states, "TVA, in a letter dated March 2, 1988 (L44 880302 817), submitted the finalized calculations for the nine critical reinforced masonry walls." The sentence should be revised to read, "TVA, in a letter dated March 2, 1988 (L44 880302 817),
submitted the finalized calculations for the nine reinforced masonry walls with critical openings."
Refer to page A4-13.
The first sentence of the second full paragraph states, "In summary, the total of 18 worst case reinforced masonry walls selected by TVA all met the NRC criteria for allowable stresses for the SSE and tornado depressurization load combinations." The sentence should be revised to read, "In summary, the total of nine worst-case reinforced wall groups and nine walls with critical openings selected by TVA met the NRC criteria for allowable stresses for the SSE and tornado depressurization load combinat ans."
5.
Deficiency D4.4-2, " Analysis of Pile Supports for the ERCH Pipeline" Refer to page A4-15 of the report.
The first sentence of the last
-paragraph states, "The analysis of the piles also assured that the dike would settle and the upper three feet of the piles would not have lateral support." The sentence should be revised to read, "The analysis of the plies also assumed that the dike would settle and the upper three feet of the piles would not have lateral support."
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Deficiency 04.6-1, " Discrepancies Between Design Calculations and Construction Drawings" Refer to the first paragraph on page A4-18. The term " support" in the l
l first, third, and fourth sentences should be revised to " support anchorage." The RIMS number in the first sentence of this paragraph should be revised from "B25 880231 457" to "B25 880130 457."
- Also, replace the second sentence with the following:
"TVA's evaluation showed that the support did not meet the design requirements specified in Attachment A to design input record SCG1S173X-1, revision 1.
However, the results of that evaluation demonstrate that the RCP support anchorage continues to meet the operability criteria for the low probability event of a combined LOCA and SSE."
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