GO2-83-678, Forwards Final Response to Notice of Violation from IE Insp Rept 50-397/83-14.Corrective Actions:Review of Quality Documentation & Receiving Records Performed to Assess Potential for Inadvertent Substitution of Reinforcing Steel

Forwards Final Response to Notice of Violation from IE Insp Rept 50-397/83-14.Corrective Actions:Review of Quality Documentation & Receiving Records Performed to Assess Potential for Inadvertent Substitution of Reinforcing Steel

ML20082B496
Person / Time
Site:	Columbia
Issue date:	07/29/1983
From:	Carlisle C WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	Sternberg D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
References
GO2-83-678, NUDOCS 8311210213
Download: ML20082B496 (9)

Text

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Washington Public Power Supply System P.O. Box 968 3000 GeorgeWashingtonWay Richland, Washington 99352 (509)372-5000 Docket No. 50-397 July 29, 1983 G02-83-678 Mr. D.M. Sternberg Chief, Reactor Projects Branch 1 U.S. Nuclear Regulatory Commission

! Region V 1450 Maria Lane, Suite 210 Walnut Creek, CA 94596

Subject:

NUCLEAR PROJECT NO. 2 NRC INSPECTION REPORT 83-14 NOTICE OF VIOLATION - AMENDED RESPONSE

Reference:

G02-83-592, dated July 1,1983, C.S. Carlisle to D.M.

Sternberg, same subject.

The referenced letter transmitted the Supply System's response to the Notice of Violation. Item A of Attachment I was transmitted as an interim response and committed to the issuance of a final report by July 29, 1983. Item A of Attachment I herein fulfills that commitment and will fully answer NRC concerns related to patched areas on concrete beams.

Additionally, we have included an amended response to Item C of the Notice of Violation. This amended response is being submitted to include additional data which is being developed as a result of a meeting between Supply System representatives and the Resident Inspec-tor conducted the week of July 18. 1983.

If you have any questions, contact Roger Johnson, WNP-2 Project QA Manager at (509) 377-2501, extension 2712.

adis '

Program Director, WNP-2 RTJ/ecmm

Attachment:

As stated cc: W.S. Chin, BPA Wl'JM i

N.D. Lewis, EFSEC A. Toth, NRC Resident Inspector Document Control Desk, NRC \ ' eq' t^$.\

.g \\1 8311210213 930729 PDR ADOCK 05000397

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Attachment 1 Page 1 of 8

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WASHINGTON PUBLIC POWER SUPPLY SYSTEM NUCLEAR PROJECT NO. 2 DOCKET N0. 50-397 LICENSE N0. CPPR-93 RESPONSE TO INSPECTION REPORT 83-14 The Supply System provides the following final response to Item A of Appendix A " Notice of Violation" and an amended response to Item C. For clarity, each violation is repeated followed by the appropriate response. The specific aspects of both items as requested by the transmittal letter are addressed within the responses.

NOTICE OF VIOLATION A. Criterion IX of 10CFR50 Appendix B states, in part, that " Measures shall be established to assure that special process...are controlled and accom-plished...in accordance with applicable codes, standards, specifications, criteria, and other special requirements." The FSAR section 3.8.4.2 identifies that ACI-301-66, ACI-318-653, and ANSI-45.2.5-74 have been adopted, to the extent applicable, in the design and construction of-Seismic Category I structures.

1. Part 7.14 of ACI-318 requires that minimum concrete protective covering for principal reinforcement, ties, stirrups or spirals in beams shall be 1) inches.

2. Part 5.1.1 of ACI-318 requires that before concrete is placed all debris shall be removed from the spaces to be occupied by the.

concrete. Part 4.4 of ANSI- N46.1.5 requires inspection of formwork for cleanliness.

3. Part 4.6 of ANSI-N46.2.5 requires that any indications of voids or-contamination shall be explored, by physical removal of concrete, if necessary, to determine the extent of such voids or contamination and that appropriate repairs shall be made.

Concrete placement and grouting procedures CP-1 and CP-3 both require cleanli-ness of forms prior to placement. Contrary to the above, on April 13, 1983, conditions existed which indicated that measures were inadequate to assure concrete repairs or placement in accordance with applicable codes.

On March 17, 1983, the civil contractor (Peter Kiewit Sons' Co.) repaired concrete beam No. 2B3 of a reactor building floor slab (room R-ll2), resulting in a completed and accepted concrete repair with visual evidence of contamina-tion in or adjacent to the repair and without exploration to determine extent.

The contamination demonstrated inadequate removal- of debris prior to concrete placement or repair.

On an unidentified date, an unidentified contractor had completed a repair to beam No. 2B11 of a reactor building floor slab elevation 470 (coordinates K-8.5) resulting in a patch with multiple cracks, lack .of bond to prior concrete, and with reinforcing steel cover of less than 1/4 inch.

This is a severity level IV violation (Supplement II).

Page 2 of 8 SUPPLY SYSTEM RESPONSE A. Action Taken In response to findings related to beam 2B3 (visual contamination consis-ting of a cigarette butt and a small piece of wood embedded at the concrete beam surface) and beam 2811 (multiple cracks, lack of bond to prior concrete and ieinforcing steel cover less than 1/4 inch), the following have occurred:

1. Beams 283, 2811 and 2B25 have been investigated.

2. Nonconformance report review to locate areas of honeycomb or voids repaired by Contract 6426. This review is continuing.

3. Drawings and quality documentation review to identify areas of congested reinforcement is continuing.

4. An investigation has been completed to identify other work approved by the quality control inspector responsible for accepting the discrepant reinforcement placement. This work is limited to Contract '

6426.

5. Nonconformances have been reviewed by the Architect / Engineer to determine the effects on the structural adequacy of the aforemen-tioned structures.

6. An interim report (G02-83-622) has been prepared to partially reply to con ~cerns of the NRC Construction Assessment Team (CAT) resulting from a recent CAT inspection at the WNP-2 Site (exit date: June 22, 1983). This report. summarizes an expanded investigation of concrete

, in the Reactor Building and responds to the concerns of Appendix A, Notice of Violation and Inspection Report 50-397/83-14 as well as providing status on actions to resolve the concerns of the NRC CAT.

A final report on the CAT concerns will be issued by the project after receipt of that inspection report.

7. A review of quality documentation and receiving records has been performed to assess the potential for inadvertent substitution of reinforcing steel in the reactor building. Contract 205 received no grade 40 steel of greater diameter than #6. Only 7% of the #6 or greater bars received by Contract 206 were grade 40. These were called out for the turbine pedestal which was placed before most of l the concrete in the reactor building. Project assessment is that inadvertant substitution of grade 40 rebar for grade 60 in the reactor building is improbable.

B. Results Achieved

1. Beam 2B3

a. During the NRC inspection, the beam was found to have visual contamination consisting of a cigarette butt and a small piece of wood embedded at the concrete surface. No explanation can be

Paga 3 of 8 ,

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provided for this contamination. A patch, resulting from repairs I of voids in the beam identified in a previous Nonconformance Report is sound.

During a reinspection of the beam, two very small pieces of wood adhering to the concrete surface were found. These were scraped off easily with a knife blade; no penetration of the surface had occurred. It was concluded that these pieces had been part of a plywood or lumber form in an area where form treatment was not complete. Another small piece of wedge 3/8" thick by 5" long was removed by knife blade from the edge of the beam.

b. The beam was excavated (chipped) full width in one place to expose the bottom layer of reinforcement.

There was no evidence of honeycomb or voids in the excavation.

The appearance of the concrete indicated better than acceptable-bond development.

Seven #11 bars were found in the bottom layer, which agrees.

with the original design requirement of 2 layers of 7-#11 bars.

The bars have 2-1/2 inches of. clearance measured from. the '

bottom of the bars to the bottom of the beam. Allowing for #5 stirrups, the net clearance to the bottom of the beam . is approximately 1-7/8 inches.

Horizontal spacing deviations were found in four places. Two rows of Richmond inserts had been placed parallel to' main.

reinforcement; the bar spacing deviations resulted from reloca- ,

tion of the bars to clear the inserts. Despite the 'close spacing, there was no . evidence of voids' .or: honeycomb in the excavated area. An NCR will be written to record the spacing deviations.

c. Beam 283 has been reanalyzed for reinforcement requirements using the original design loading. (The analysis, in progress at the time of submission of the interim report, has now been completed.). The original reinforcement consisted of 14-#11 bars in two layers of 7 bars per layer. The. reinforcement required for the most critical . loading combination is 6-#11 bars,' bottom -

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reinforcement.

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d. Honeycomb and voids .which are the result of- poor consolidation <

can be expected to .have surface indications of their presence.

Those areas in beam 283 have been found,' excavated, and. re-paired.L The repair has been found to be sound.

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The . concrete in the.. excavation - is sound; bond development' is .

better than acceptable. The number of bars furnished is greater:

than the number required for future loading conditions..

It is concluded that beam 283 .is structurally adequate .for the'

. purpose intended and does not jeopardize the structural integri-t _b

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e Page 4 of 8 ty of the Reactor Building.

2. Beam 2B11 ,

a. During the NRC inspection, a seven-foot long repair patch for-beam 2B11 was found to cor,tain multiple cracks, lack of bond to original concrete, and a reinforcing steel cover of less 'than 1/4 inch. .

b. The beam repair patch was removed. Three excavations were performed: two in the patch and a,e toward' the midspan of the beam. The excavations were, performed full width of the beam to expose the bottom layer of bars.

The original design provided 24-#11 bars in three layers of 8-#11 bars per layer. The midspan excavation contains 8-Jil s bars in the bottom layer.

A second excavation contained 8-#l1 bars and 7-#11 dowels and is within the area of the excavated 7-foot long patch.' A small amount of honeycomb was observed but ,it was not established whether this was a remnant from the defective patch or a portion of the original honeycomb which had not been removed during the earlier repair.

The third excavation nearest the bioshield wall and within the area of the excavated 7-foot long' patch, contains 7-#11 bars with 7-#11 dowels. Some honeycomb was observed which is question-able as to source.

The bars had 2-1/2 to 2-3/4 inches clearance measured from the bottoms of the bars to the bottom of the beam. Allowing for #5 stirrups, the net clearance to the bottom of the beam is approximately 1-7/8 inches.

Horizontal spacing deviations were found in the excavations.

These resulted from the relocation of bars to accommodate two rows of Richmond inserts. These relocations, plus the placement of dowels in the same horizontal plane as the main bars contributed to the development of hcneycomb. No honeycomb was in the midspan excavation which is out of the dowel placement area. It is not clear whether the small amount of honeycomb in the excavations in the patched area is a remnant of the patch or is part of the original concrete. In either case the deficient area will be excavated to sound concrete before patching.

Beam 2B11 has been reanalyzed for reinforcement requirements.

The original design was based upon a loading combination which included construction loading and provided for 24-#11 bars in 3 layers of 8-#11 bars in each layer. The . reanalysis, which

! provides for the future critical loading, requires only one l bottom layer of 5-#11 bars.

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c. The ACI! Code .does not require af matching dowel for every main bar . provWer for positive moment. The missing (or relocated)-

dowel:is nnt required for' structural adequacy of the beam.

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While > honeycomb has been found in the excavation, the amount is s , relatively small and is localized. The questionable.effect of a small' amount ,of honeycomb on bond' development must be weighed against the fact that #11 bars are, provided when only 5-#11 barsf are ncy needed for future normal ~and safe shutdown loading conditions.

It is cdn#cluded that beam 2Bil is7 structurally adequate for the purpose' int 6nded and does not jeopardize the structural ~ integri-ty of the Reactor Building.

3. Beam 2825

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a. Durinh 'the NRC inspection, the ' beam was found to have. one defective patch resulting from a lack of . bond to the original concrete. These repairs had .been . performed in response to Nonconformance Reports after the original concrete placement.

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b. repair patch was excavated. Two. excavations full. width of-the beam were performed to expose the' bottom layer of reinforce-

, ment: one in the patch area, the second- toward the midspan of j

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the beam.

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I A smal1 amount of honeycomb,. thought to be a rennant of the 1 -defective ~ patcW, was found in one excavation near the bioshield

, wall. No honejcomb was found in the second -excavation. The

appearhnce of the concrete indicated better- than acceptable

} bond developme'nt.

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+ Eight' #11 tiars. were found in the bottom. layer 'of the midspan-

,f , iexcavation;/8-#11 main bars and 8-#11 dowels were found in the.

lev > .f e,ccavation near thelbioshield wall. The original design required P

24-#11 bars in, three. layers of .8-#11 per layer.

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1 The(bars ~ have'2-1/2 + 1/2 inches' of clearance measured from the bottbms of the bars to the bottom of the beam. Allowing for #5

( .. -s'tirrups, s the' net clearance. from the stirrups to the bottom of -

s -the beam ns approximately 1-1/2 inches.

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. . Horizontal spacing deviations were found in' the excavation near

% tna bioshield3  : wall; :one: spacing ' deviation-' was found in. the . -

, . . . other excavation. -These deviations Lresulted from , relocation of -

>' d -bars to ' accommodLte 1 Richmond . inserts, ' and from ' placementlof idowels in the sa^ma horizontal plane.as the main bars.

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J .c. Beam - 2825--has - been reanalyzed for reinforcement .' requirements.f .

, The original design was based uponL a loading combination which-3

-included construction loading and- provided for 24-#11 bars in:3:

g. - layers: of.- 8-#111in each layer. The; reanalysis',Lwhich provides:

7 -for, the future critical.1oading, requires only. one bottom .1ayer

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Page 6 of 8 of 5-#11 bars.

While honeycomb ~ has been found in the excavation (and could be a remnant of the defective patch), the amount is relatively small and is - localized. Ths area will - be excavated to sound concrete before patching. The questionable effect of a small amount of honeycomb cn bond development must be weighed against the fact that 24-#11 bars are provided when only 5-#11 bars are now needed for- future normal and safe shutdown loading condi-tions.

d. Honeycomb and deviations -in- bar spacing have been found in the-excavation near the bioshield wall. Analysis indicates that this excavation is -in an area of negative moment and only minimum reinforcement to satisfy ACI code requirements is re-quired. Since only 5-#11 bars are required for maximum positive moment near the midspan of the beam, it follows that the 24-#11 furnished at the support provide a very conservative design.

It i concluded that beam 2B25 is structurally adequate tcr the purpose intended and does not jeopardize the structural integri-ty of the Reactor Building.

C. Expansion of' Investigation The Construction Assessment Team recently completed an inspection of WNP-2 (exit date: June 22, 1983). It .is expected that their report of inspection will contain findings on concrete. An interim report of additional investigations pertaining to - the CAT issues (G02-83-622 dated 7/15/83) has been transmitted' to Region V. The project considers that the final report on the CAT issues will completely address an expanded investigation of concrete beams and -other structures in the Reactor Building.

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Page 7 of 8 l

NOTICE OF VIOLATION i

C. Criterion III of 10CFR50, Appendix B states, in part, that design control )

measures "shall include provisions to assure that appropriate quality '

standards are specified and . ,cluded in design documents and that devia-tions from such standards are controlled." FSAR drawing M539 and Table 3.2.1 identify the piping and associated components of the floor drain system, upstream of primary containment isolation valve FDR-V-4, as Quality Class I. This invoked appropriate quality standards and related quality control inspections.

Contrary to the above, on November 11, 1982 Burns and Roe issued design change PED-215-H-G046, which improperly downgraded the quality class of (at least) pipe supports FDR-900N, 90lN, 902N, and 903N from Quality Cl as;. I to Quality Class II. The design change itself appeared to be improperly classified as Quality Class II. The improper downgrading was not identified by the signatory reviewers of the design change. The installation of (at least) pipe support FDR-900N did not receive indepen-dent inspection by quality control personnel, nor was it included in the as-built program for final engineering verification.

This is a severity level IV violation (Supplement II).

SUPPLY SYSTEM RESPONSE Letter G02-83-592, C.S. Carlisle to D.M. Sternberg, dated July 1, 1983 provided our interim response in regards to corrective action taken/results achieved and action taken to prevent reoccurence. The following information is provided as supplemental information to update action taken to preclude reoccurence.

To ensure that the above decribed condition does not exist in Project Engineer-ing Directives (PED's) issued by other disciplines of the A/E, the project has developed a sampling plan by which a 95% confidence level can be established that this condition does not exist in other disciplines.

The sampling plan to provide a 95% confidence level that less than 5% defects exist in the sample lot is as follows:

Sample Selection A computer listing of all PED's issued (approximately 29,000) has been generated, and all PED's assigned a sequential number of 1 through 29,000. Then a random computer listing of numbers was generated. Utilizing the list of random numbers, select the PED assigned the sequence number which corresponds to the random number. This selection will be broken down into a sample size for Quality Class I (QCI) ari Quality Class II (QCII) PED's.

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Page 8 of 8 Analysis The PED's vill then be analyzed as follows:

e Quality Class II - determine and review the baseline drawing appli-cable to the PED and verify that the PED is appropriately identified in regards to Quality Class.

e Quality Class I - Review each PED in the sample size to ascertain whether or not the PED was appropriately reviewed / checked prior to being approved and issued.

Completion of Sample Program It is anticipated that the sample program will be completed by September 30, 1983. A status report will be issued August 31, 1983 describing percent of program completion at that time and findings to date.

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