U-600309, Responds to NRC 851001 Request for Licensee Investigation of Employee Concerns Re Instrumentation Lines Closed W/Sugar & Unacceptable Methods for Making Welds in Tacks.Summary of Results of Review Encl

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Responds to NRC 851001 Request for Licensee Investigation of Employee Concerns Re Instrumentation Lines Closed W/Sugar & Unacceptable Methods for Making Welds in Tacks.Summary of Results of Review Encl
ML20136H562
Person / Time
Site: Clinton Constellation icon.png
Issue date: 11/01/1985
From: Hall D
ILLINOIS POWER CO.
To: James Keppler
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
U-600309, NUDOCS 8511250135
Download: ML20136H562 (5)


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U-600309 L30-85(11-01)-L 1 A.12 0

  • ILLINDIS POWER COMPANY CLINTON POWER STATION, P.O. BOX 678, CLINTON, ILLINOIS 61727 November 1, 1985 PRICRI

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Docket No. 50-461 \ g I. .

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Mr. James G. Keppler -

Regional Administrator Region Ill U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137 Subj ect:

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Licensee Investigation of Employee Concerns

Dear Mr. Keppler:

This letter is in response to C. E. Norelius' (NRC) letter to W. C. Gerstner.(Illinois Power) dated October 1, 1985. This letter submitted an employee concern to Illinois Power (IP) and requested that IP review and follow up on the matter. IP has completed a review of the concern and has enclosed a summary of our results. Supporting-documentation that provides further detail in support of the information provided in the enclosure has been compiled and is being maintained at Clinton Power Station for inspection by Region III personnel.

Illinois Power welcomes the opportunity to assist in inves-tigating and resolving employee concerns. We trust that the enclosed material is adequate to provide you with a general assessment of IP's results and for subsequent use by your office.

. Sincerely yours, l . . Hall Vice President RDW/jsp Enclosure

.cc: Director, Office of the I&E, USNRC, Washirigton, DC 20555 B. L. Siegel, NRC Clinton Licensing Project Manager NRC Resident Office Illinois Department of Nuclear Safety Mark Jason, Assistant Attorney General, State of Illinois 8511250135 e51101 NOV 51985 PDR A

ADOCK 05000461 PDR l hog ,

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ENCLOSURE i

Summary of Investigation Results L

REFERENCE:

NRC letter dated October 1, 1985.(Mr. C. E.

Norelius,.NRC to Mr. W. C. Gerstner, Illinois Power Company)

Employee Concern i 1 (as stated'in referenced letter to Illinois Power)

It is' with "possible sugar". that many instrumentation A thorough flush could not lines take are almost place. Theclosed welding-procedure used to weld " Cajon" fittings to .065" wall

' instrumentation tubing, NP-8-8-BS, was defective. It'is not

.possible to make consistently good welds on this wall thickness using_the minimum requirements of this procedure, i.e., 300*F maximum interpass temperature, 50 amps minimum, and no internal purge.

Summary of IP Investigation Results

-This employee concern' alleges two (2) adverse conditions:

1) The possible blockage of instrument lines, and
2) Welding Procedure NP-8-8-BS, would not consistently

_ produce a good weld when used to weld " Cajon" fittings to .065" wall instrument tubing.

The possible blockage of instrument lines (condition 1) is addressed later in this enclosure in Illinois Power's response to Employee Concern _f3.

The welding procedure concern (condition 2) was previously identified to Baldwin Associates -(BA) Technical Services (TS)

Management and the "SafeTeam" in 1984. As a result, BA issued a Corrective Action Request (CAR) 209, on October 29, 1984, to document the potential problem and provide resolution.

One of-the. corrective actions initiated by CAR-209 was the re-verification of Welding Procedure NP-8-8-BS, using a variety of combinations <of welding parameters, including the minimum requirements of the procedure. It was found that the welding procedure was capable of_ producing acceptable welds.

Additional corrective action for CAR-209 involved the selection of samples of field production welds of " Cajon" fittings to .065" tube, welded in accordance with the suspect procedure. These samples were selected.by BA TS inspectors for evaluation and

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r testing by an' independent lab. The test results were evaluated

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by the CPS Architect Engineer and concluded that the presence of melt-through and sugaring has no detrimental effect on the strength of the -joints.

Corrective action taken from. CAR-209 also included welder train-ing in a refined welding technique to further assure the highest quality weldment within the parameters of Welding Procedure

.NP-8-8-BS.

~Since it was demonstrated that the welding _ procedure was capable of producing acceptable welds, welders were trained to the welding. procedure and acceptable welds were present in the field, this employee concern could not be substantiated. No corrective action is required on this employee concern.

Employee Concern # 2 (as stated in referenced letter to Illinois Power)

Acceptable welds were produced by making the welds in tacks about 1/4".long and cooling with water mist to ambient temaerature between tacks. This method was not used-for the bulk of field welding on-this material at Clinton.

Summary of IP Investigation Results During the investigative actions taken to resolve CAR-209, the weld parameters of suspect Welding Procedure NP-8-8-BS were re-verified using various combinations of parameters and tech-niques, including those identified in this employee concern and those representative of field conditions.

It was found that the welding procedure'was capable of producing quality welds using various methods. representative of field t conditions. .Further, as identified in employee concern il above, l production field welds were chosen by BA TS inspectors, removed and tested by an independent lab and found acceptable. The welding technique described in the employee concern is allowed as a good practice but is not required to achieve acceptable welds.

The employee concern, although substantiated, does.not have

[ significance.

concern.

No corrective action is required on this employee I

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. Employee Concern f 3

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- (as stated in referenced letter to Illinois Power)

Radiographs of welds 1-IS-912-4, 1-CM-905-92Q1, 1-CM-905-2Q1,

~1-CM-905-91, and 1-SM-906-5Q2 revealed severe burn-through and

-internal restrictions.

Summary of IP Investigation Results IThe identified radiographs of field welded instrumentation piping were re-reviewed on October 9, 1985, and did identify some. .

t melt-through (not burn-through) and evidence of some internal '

restrictions. caused by the melt-through. -.The Reviewer stated ..

that'even in the most severe case the melt-through condition had not. sealed off the pipe. The results of this review.were

- . discussed with the CPS Architect Engineers' Mechanical Project Engineer who' confirmed that a sealed off pipe would be the only

- condition.that would affect the operability of the instrument.

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Further,. review of Startup testing-procedures indicates that f, instrument lines are routinely flushed during the checkout and-

initial operation phase of CPS that would verify that the lines are not blocked.

^^ The employee concern was substantiated, in that some melt-through-

,i and' internal restrictions were found, but does notzhave signifi-cance.. No corrective action is required on this employee con-cern.-

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  • p Employee Concern.f 4 .

(as stated in reference letter to Illinois Power)

F i Minimum, wall thickness violations.may exist. Training given

. inspectors on the use of D-meters would result in inaccurate readings:(readings that would indicate the material was thicker than actual)....The training was not. modified after this probl'em was brought to the attention of BA. ,

{4J Summary of IP Investigation Results E Investigation of-this employee concern found that the same concern was previously expressed to the Manager - Technical Services.on March- 26, 1985, by a concerned Technical Services Inspector. The Technical Services Inspector received a written

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l response from the Manager - Technical Services, on March 29, 1985, stating that if the instructions contained in Technical

. Services Instruction, TSI-012, (the instruction for use of the D-meter) are.followed, accurate measurements will be obtained.

An interview of two (2) BA Certified Level.II Welding. Inspectors 3 confirmed that required training in the use of the D-meter was provided, however, some weaknesses in the training program for

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D-meter usage were noted. When asked what meter setting they were-using for stainless steel thickness measurements, each inspector gave a different number for the setting (one gave the number 222, the other gave 233). Each inspector further stated that.the number they were using was provided in training. A review of instruction,JTSI-012, and the Manufacturer's Operating Manual determined that the setting specified in documented 4 procedures is 232. However, discussions with lead Technical

~n Services. personnel revealed that the number 222 was provided in training and is,~by' calculation, the most precise number to use on stainless steel.

A review of the effects of using a meter setting of 232 or 233, when measuring stainless steel, indicated that accurate thickness V measurement would be obtained. However, by calculation, a meter

, q setting of 222, as provided in training, is a more precise figure sand gives highly accurate readings for stainless steel thickness measurements. Therefore, although a training program weakness

-was confirmed, no adverse hardware impact would result, since any difference in thickness readings would be in the more precise

"' direction.

BasedEon the above information, the responr2 provided by the BA Manager-Technical Services to the original employee concern was appropriate and did not require modification to the training

.' given to inspectors for use of the D-Meter, since training provided the most' accurate and precise information.

This concern'could not be substantiated. However, a weakness was

-found in that procedures do not formally document the D-Meter settings established for_ stainless steel by calculation and as provided in training. Corrective action has been initiated on this programmatic weakness.

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