ML19261C715

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Responds to NRC 790306 Ltr Re Violation Noted in IE Insp Repts 50-445/79-03 & 50-446/79-03.Corrective Actions: Elephant Trunk Length Increased to Reduce Concrete Free Fall,Qa Procedures Changed & Emphasized
ML19261C715
Person / Time
Site: Comanche Peak  Luminant icon.png
Issue date: 03/06/1979
From: Gary R
TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To: Seidle W
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19261C714 List:
References
TXX-2967, NUDOCS 7903280290
Download: ML19261C715 (3)


Text

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TENAS UTII.ITIES GENERATING CO.TIl%NY 200: nnvAN Towen . Dat.t AS. TEXAS 7&201 h /j March 6, 1979 O k[Cy[Q g TXX-2967

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a Mr. W. C. Seidle, Chief Reactor Construction and h 4 Engineering Support Branch 'd f q U. S. Nuclear Regulatory Commission 9 Office of Inspection & Enforcement 611 Ryan Plaza Dr., Suite 1000 Docket flos. 50-445/Rpt. 79-03 Arlington, Texas 76011 50-446/Rpt. 79-03 COMAtlCHE PEAK STEAM ELECTRIC STATION 1981-83 2300 MW IllSTALLATION RESPONSE TO NRC INSPECTION REPORT DATED FEBRUARY 20, 1979 DOCKET N05. 50-445 & 50-446 FILE NO. 10130

Dear Mr. Seidle:

We have reviewed the report dated February 20, 1979, on the inspection conducted by your resident inspector, Mr. R. G.

Taylor, of the activities authorized by NRC Construction Per-mit No. CPPR-127 for the Comanche Peak facility. We have responded to the findings listed in Appendix A of that report.

To aid in the understanding of our response, we have repeated the requirement and your findings followed by our corrective action.

We believe the attached information to be responsive to the Inspector's findings. If you have any questions, please advise.

Very truly yours, R. J. Gary RJG:dla Attachment

?S03280240

Inspection Report 79-03 TXX-2967 Page 2 NOTICE OF VIOLATION Based on the results of the NRC inspection conducted on February 15, 1979 it appears that certain of your activities were not conducted in full compliance with the conditions of your NRC Construction Permit No. CPPR-127 as indicated below:

Failure to Follow Concrete Placement Procedure Criterion V of Appendix B to 10 CFR 50 requires that activities affecting quality shall be accomplished in accordance with docu-mented instructions, procedures, or drawings of a type appropriate to the circumstances.

Project Quality Procedure QI-QP-11.0-3 references Specification 2323-SS-9, " Concrete," which invokes Section 8.3 of ACI 301-72 for depositing of concrete. Paragraph 8.3.3 of ACI 301-72 states that, " Concrete shall not be subjected to any procedure which will cause segregation."

Contrary to the above:

During concrete placement 201-5805-019 (Unit No. 2 Containment Wall) on February 15, 1979, at approximately 11:15 a.m., the Resident Inspector observed that concrete was free-falling from

" elephant-trunks" and impinging on reinforcing steel prior to reaching the deposit surface. Concrete segregation was evidenced by coarse aggregate emanating from the stream of falling concrete.

This is an infraction.

Carrective Steps Which Have Been Taken and Results Achieved:

Immediate corrective action was taken by increasing the " elephant trunks" length (thereby reducing the exposed free fall of the concrete) und aligning the " elephant trunks" to provide no impingment of concrete on rebar and/or liner ties.

This action eliminated any segregation of the concrete.

Corrective Steps Which Will Be Taken To Avoid Further Noncompliance:

Concrete placement and civil QC personnel were instructed to pay particular attention on future concrete placements to location of

" elephant trunks" to preclude possibility of segregation.

Inspection Report 79-03 TXX-2967 Page 3 Corrective Steps Which Will Be Taken To Avoid Further Noncompliance:

Continued Additionally, a checklist item for QC verification during preplace-ment inspection was added to the preplacement inspection checklist to verify " elephant trunk" location free from interference with rebar and liner ties.

Date Of Full Compliance:

February 21, 1979