ML20095G976

Submits Clarifying Info to Re Results of QC Inspector Reinsp Program,Per Insp Repts 50-454/82-05 & 50-455/82-04.Reinsps of Equipment Setting & Equipment Mod Clarified

ML20095G976
Person / Time
Site:	Byron
Issue date:	08/22/1984
From:	Delgeorge L COMMONWEALTH EDISON CO.
To:	Kepplr J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
NUDOCS 8408280274
Download: ML20095G976 (2)

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( J Address Reply to. Post Office Box 767

\ ,4 Chicago, Illinois 60690 August 22, 1984 Mr. James G. Keppler Regional Administrator U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137

Subject:

Byron Generating Stations Units 1 and 2 Bryon QC Inspector Reinspection Program I&E Inspection Report Nos. 50-454/82-05 and 50-455/82-04 References (a): L.O. DelGeorge Letter to J.G. Keppler dated February 24, 1984 (b): L.O. DelGeorge Letter to J.G. Keppler dated July 3, 1984

Dear Mr..Keppler:

This letter provides clarifying information regarding some of the data presented in reference (b) regarding the results of the Byron QC inspector reinspection program.

This-information is.provided at the suggestion of a Region III inspector who has been involved in the detailed review of the June 1984 Supplement to the report on that reinspection program.

Chapter III of the June. Supplement summarizes the results of supplemental inspections and evaluations for objective Hatfield inspection attributes. Sections III.B and III.C contain data on reinspections of equipment setting and equipment modification, respectively, which could be misinterpreted.

Relative to equipment setting, the report states "A total of 778 items were inspected and 34 discrepancies were identified". The number 778 refers to the number of inspections performed. Each of these inspections may consist of one or more elements. For example, the inspection of an equipment anchoring detail may consist of the objective examination of a welded holddown to assure-that each of six welds is present. An entire inspection was termed discrepant if any element of that inspection contained a discrepancy.

Using the previous example if one of the six welds were discrepant, the entire inspection was considered discrepant.

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.. If two welds of the six were discrepant, the entire inspection was still considered as a single discrepancy. The total number of inspection elements was considerably larger than the total number of inspections (778). Similarly, the total number of discrepant elements was greater than the total number of discrepant inspections (34). The results are presented in terms of inspection performed and inspections found discrepant because of the difficulty in counting all of the individual elements. For inspections containing more than one element, the number of discrepant elements was much smaller than the number of inspection elements for each inspection. This representation conservatively represents the quality of the work since the ratio of discrepant elements to elements inspected is smaller than the ratio of discrepant inspections to the number of inspections.

Relative to equipment modification, the report states "A total of 1,850 items covering a considerably larger number of inspection points were inspected and 44 discrepancies were identified". Similar to equipment setting, the number 1,850 refers to the number of inspections that were performed. An inspection of termination locations in a particular section of a panel was considered as one inspection.

This inspection may include examination of approximately 250 terminal locations, each of which is considered an inspection point. If any of these inspection points was found to be discrepant, the inspection is considered to be discrepant.

The 44 discrepancies stated in the report represent 44 discrepant inspections. The number of discrepant inspection points is larger than the 44 discrepant inspections. However, the number of discrepant inspection points was much smaller than the number of inspection points for each inspection.

As with equipment setting, this represents a conservative presentation of the results. The ratio of discrepant inspection points to the total number of inspection points is considerably smaller than the ratio of discrepant inspections to the total number of inspections. As with equipment setting, the results were presented in terms of inspections rather than I

inspection points beca2se of the difficulty in determining the exact number of inspection points.

Please address further questions regarding this matter to this office.

Very truly yours4 1 /

. L, L.O. DelGeorge Assistant Vice-President cc: Mr. H.R. Denton Mr. R.C. DeYoung