IR 05000311/2008010

Insp Rept 50-458/85-09 on 850311-0810.Violations Noted: Failure to Adequately Check Calculations,Document & Verify Assumptions & Provide Basis for Design Input

ML20140D811
Person / Time
Site:	Salem, River Bend
Issue date:	01/23/1986
From:	Ireland R, Tapia J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:
Shared Package
ML20140D752	List: IR 05000311/2008010 ML20140D749 ML20140D770
References
50-458-85-09, 50-458-85-9, NUDOCS 8602030118
Download: ML20140D811 (16)

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APPENDIX B U.S. NUCLEAR REGULATORY COMMISSION

REGION IV

NRC Inspection Report:

50-458/85-09 CP:

CPPR-145 Dockets:

50-458 Licensee:

Gulf States Utilities P. O. Box 2951 Beaumont, Texas 77704 Facility Name:

River Bend Station Inspection At:

River Bend Station, St. Francisville, Louisiana Stone & Webster Engineering Corporation Cherry Hill, New Jersey Inspection Conducted:

March 11-15, April 1-5, 22-23, May 14-16, 21-24 June 3-6, August 6-10, 1985 f

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Inspector:

ss9C4t-t 2A BG SecN' pia, Reactor (hspector, Engineering I. ga Date J.

n, Reactor Santy Branch Accompanying Personnel:

H. R. Fleck, Consultant W. P. Chen, Consultant Approved:

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R. E. Ireland, Chief, Engineering Section Date Reactor Projects Branch Inspection Summary Inspection Conducted March 11-15, April 1-5, 22-23, May 14-16, 21-24 June 3-6, August 6-10, 1985 (Report 50-458/85-09)

Areas Inspected:

Special, announced inspection of seismic Category I cable tray and conduit supports design.

The inspection involved 280 inspector-hours onsite by one NRC inspector and two consultants.

9602030118 860129 PDR ADOCK 05000458 G

PDR

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-2-Results: Within the areas inspected, these violations were identified:

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Failure to Adequately Check Calculations B.

Failure to Document and Verify Assumptions C.

Failure to Provide Basis for Design Input D.

Failure to Provide Adequate Disposition of Construction Deviation i

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-3-DETAILS 1.

Persons Contacted Gulf States Utilities (GSU)

• W. H. Benkert, Lead Quality Engineer

• C. M. Coones, Structural Engineer K. E. Schrke, Projects Planning and Coordination, Manager L. A. England, Licensing Supervisor T. C. Crouse, Quality Assurance Manager R. B. Stafford, Quality Services Manager Stone & Webster Engineering Corporation (SWEC)

T. Years, Lead Structural Engineer, Site Engineering Group (SEG)

M. A. Stein, Structural Engineer, SEG K. S. Jadeja, Lead Structural Engineer, Cherry Hill Operation Center (CHOC)

N. H. Amin, Principal Structural Engineer, CH0C W. T. Tucker, Engineering Assurance Engineer, CH0C F. A. Canuso, Project Engineering Assurance Engineer, CHOC J. C. Bisti, Project Engineer, CH0C M. Alimed, Structural Engineer, CH0C J. M. Lord, Engineering Assurance Manager, CH0C R. A. Berry, Assistant Project Engineer, CH0C R. Aurich, Project Quality Assurance Engineer, CHOC M. J. Shah, Structural Division, Assistant Manager, CH0C S. Feldman, Mechanical Section Manager, CHOC C. Jankauskas, Structural Engineer, CH0C The NRC inspector also contacted other licensee personnel including administrative, clerical, and technical personnel.

• Denotes those present at the exit interviews conducted subsequent to the completion of each inspection phase.

2.

Design of Cable Tray and Conduit Supports An inspection was conducted of the design of the River Bend Station (RBS)

seismic Category I cable tray and conduit supports. The inspection was performed to verify that the design criteria and implementation for these supports were in compliance with the support design conrnitments as delineated by the licensee, GSU in the RBS Final Safety Analysis Report (FSAR).

The inspection of the seismic Category I cable tray and conduit supports included:

(1) reviews of the design process for the supports employed by the architect / engineer (AE), SWEC; (2) reviews of design calculations performed by SWEC in their New Jersey, CH0C and SEG offices, and (3) verification of as-built condition of samples of the supports installed inside and outside the RBS reactor building (RB).

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-4-l The inspection found that the RBS seismic Category I cable tray and conduit supports were procured and designed in accordance with the requirements of:

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a.

SWEC Specification 248.000, " Electrical Installation," Revision 0, j

August 16, 1976, through Revision B, Addendum No. 1, March 28, 1985.

b.

SWEC Document 200.010, " Structural Design Criteria," Revision 0,

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January 8, 1975, through Revision 4, March 15, 1985.

A review of the procurement specification and structural design criteria (SDC) identified above disclosed that the requirements specified therein

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were adequate to assure that the supports would be designed in accordance i

with the licensee's commitments in Section 3.10.3.A and 3.8.4.3.3 of the RBS FSAR.

The review of the FSAR commitments found that:

Section 3.10.3A, " Methods and Procedures of Analysis or Testing of

Supports of Electrical Equipment and Instrumentation," stated that the

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dynamic analysis method was to be used to determine support parameters

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(geometry, size and spacing) for cable tray systems with Operating Basis Earthquake (OBE) and Safe Shutdown Earthquake (SSE) loadings based on two percent and four percent critical damping, respectively.

This section also states that normal working stresses were to be maintained during the OBE condition and that no adverse deformation

or failure was to occur during the SSE condition.

i Section 3.8.4.3.3 of the FSAR, " Loading Combinations for Steel

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Structures," stated that seismic Category I steel structures were l

to be designed in accordance with the AISC Steel Construction Manual j

(7th edition) except that the 33 1/3 percent increase in the allowable stress when earthquake and wind loads are present in loading combina-

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tions was not used.

Section 3.8.4.3.3 also stated that the allowable stress was to be as defined in Part 1 of the AISC specification for the design, fabrication and erection of structural steel for buildings, dated February 12, 1969, with its supplements and Section 1.5.2 of this AISC Specification dated November 1, 1978 (The February 12, 1969, and November 1, 1978, issues of this AISC specification were contained in the 7th and 8th editions, respectively, of the AISC Steel Construction Manual).

Additionally, Section 3.8.4.3.3 defined the loading combinations under varying loading conditions to be considered in the support design.

Combinations for normal, severe,

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extreme, abnormal / severe, abnormal / extreme and extreme loading

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-5-conditions were specified in Equations 12-22.1 for seismic Category I steel structures. The review also found that the preceding FSAR requirements were adequately reflected in the current issue, Revision 4, of the SDC SWEC Document 200.010.

Specifically:

The requirements of Section 3.10.3A of the FSAR regarding the

percent of critical damping to be utilized in dynamic analyses were contained in SDC Sections 6.7.1, seismic Category I cable tray supports, and 6.7.3, criteria for Category I cable tray and conduit support system in the RB.

The requirements of FSAR Section 3.10.3A of the FSAR regarding

stresses during the OBE and SSE conditions as qualified in the load c.ombination requirements in FSAR Section 3.8.4.3.3 were also contained in Sections 6.7.1 and 6.7.3 of the SDC.

SWEC Document EMTG-4A was specified as a guideline for the design of supports except those inside the RB.

The requirements of FSAR Section 3.8.4.3.3 regarding the

allowable stress were contained in Section 4.1.2, " Steel Structures," of the SDC.

3.

Design Methodology During the inspection a review was conducted of the history of licensee's design methodology for the design and analysis of seismic Category I cable tray and conduit supports.

This review was conducted to enable the items of inspection to be assessed within their proper historical perspective.

The review disclosed that since 1975, responsibility for the design of the RBS seismic Category I cable tray supports had been held by three SWEC CH0C Divisions.

Prior to 1976, this responsibility was held by the SWEC CH0C Power Division.

However, this responsibility was transferred in 1976 to the Engineering Mechanics Division and in 1977 to the Structural Division.

Furthermore, since 1979, support design calculations were performed by both SWEC CHOC and SWEC SEG organizations.

The review found that there were 227 and 2273 seismic Category I cable tray supports inside and outside the RB, respectively, and that supports inside and outside the RB were constructed from different materials and qualified by different procedures.

The 227 seismic Category I cable tray supports inside the RB were constructed from ASTM A500 Grade B tubular structural steel and ASTM A36

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structural steel shapes with welded connections.

These supports were qualified on the basis of either:

(1) analyses of specific supports or (2) comparisons of other supports with specific supports which had been determiningthatsupportswereof"similardesign"gesecomparisonsin analysed.

Engineering judgement was utilized in t The special cases

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paragraph of Section 6.7.1, " Seismic Category I Cable Tray Supports," of the SDC, Revision 2, July 8, 1983, through Revision 4, March 15, 1985, permits qualification of supports by the second of these two methods.

Section 6.7.1 states that support configurations not covered by the EMTG-4A guideline should be qualified and documented as special either by establishing similarity or conservatism to a previously3 qualified design or by performing computer analyses or hand calculations. The specific g'

supports analysed included typical trapeze, riser, cantilever, teg, floor mounted 'and one-of-a-kind type of supports.

A review of a sample of

See: (1) SWEC Drawing 12210-EE-340AE-3, " Seismic Cable Tray Support, Standard Details, Reactor Building, " Revision 3, August 27, 1984.

(2) SWEC Drawing 12210-EE-340AF-2, " Seismic Cable Tray Support, Standard Details, Reactor Building," Revision 2, August 27, 1984.

(3) SWEC Drawing 12210-EE-340YY-4, " Cable Tray Supports, Tabulations, Reactor Building," Revision 4, November 27, 1984.

(4) SWEC Drawing 12210-EE-340YZ-4, " Cable Tray Supports, Tabulations, Reactor Building, " Revision 4, November 27, 1984.

See: SWEC Calculations No. ES-1090, " Cable Tray Supports - Reactor Building," Revision 1, April 26,1984, p. ES.1097.

See: SWEC Calculation No. ES-1090, " Cable Tray Supports - Reactor Building," Revision 1, April 26, 1984, pp. ES. 1098-ES.1111.

See: (1) SWEC calculation ES.1300, " Reactor Building Cable Tray Analysis," Case R1, August 23, 1982, pp. ES.1318-ES.1343.

(2a) SWEC calculations ES.1300, " Reactor Building Cable Tray Analysis," Case 42, August 18, 1982, pp. ES.1344-ES.1351.

(2b) SWEC calculation ES.4000, " Cable Tray Supports Attached to Steel Containment," September 26, 1983, pp. ES.4025-ES.4037.

(3) SWEC calculation ES.1300, "R. B. Cable Tray Supports No. 83 and 84," Lease R3, August 19, 1982, pp ES.1353-ES.136 '

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-7-specific supports analysed found that the three-dimensional (3D) static and dynamic computer analyses of the designs were performed using the Structural Design Language (STRUDL) computer program versions ST-346 STRUDL-SW, version 03, July 1982 and ICES STRUDL, version V2 M2, July 1972, respectively, and that the results of the STRUDL-SW static analyses were combined by a SWEC developed STRUDL-SW post progressive program entitled Combine-Forces.

The resulting combinations were in accordance with the load combination requirements of the previously cited SWEC Structural Design Criteria (SDC) and the RBS FSAR.

The 2273 seismic Category I cable tray supports outside the RB were constructed from ASTM A570 Ggade 30 material with a minimum yield strength of 38 ksi after cold forming.

These supports were qualified on the basis of worst case two-dimensional (20) static and dynamic computer analyses of standard or special support configurations and with multiplication factors appliedtotheresultsofthegDanalysestoaccountforthe3Deffectsin the cable tray support systems.

The standard configurations of supports outside the RB whi h were analysed were similar to those inside the RB.

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review of a sample of these 2D computer analyses found that the static and dynamic analyses were performed using the ICES STRUDL-II Version V2 M2, June 1972 computer code and that load combinations were performed by manual calculations.

These load combinations were in accordance with the SDC requirements and FSAR commitments.

Seismic Category I conduits are supported at a maximum span of 8 feet.

This maximum span and the accompanying design concepts defined in CHOC Engineering Mechanics Division Technical Report, EMTR-401-0, August 15,

See: (1) SWEC Drawing 12210-EE-3404A-8, " Cable Tray Support Details,"

Revision 8, August 27, 1984.

(2) SWEC Drawing 12210-EE-34048-9, " Cable Tray Support Details,"

Revision 9, August 27, 1984.

See: SWEC Calculation ES.1, " Category I Cable Tray Support Analysis,"

November 10, 1983, pp. 1-3.

See: (1) SWEC Calculation ES.1, " Category I Cable Tray Support Analysis,"

Lease-29, July 30, 1979, pp. ES.66, ES.69, ES.311-ES.314.E.

(2) SWEC Calculation ES.1, " Category I Cable Tray Support Analysis,"

Case 30, July 31, 1979, pp. ES.70-ES.71, ES.314D-ES.314E.

(3) SWEC Calculation ES.1, " Category I Cable Tray Support Analysis,"

Lease 32, July 14, 1979, pp. ES.74, ES.315-ES.31 _ - _

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s-8-1980, were qualified by equivalent static analysis.

This design technique has been verified by dynamic analysis and is in accordance with the SDC requirements and FSAR commitments.

4.

Design of Cable Tray Supports Inside The RB The inspection found that the 227 seismic Category I cable tray supports inside the RB were qualified either on the basis of STRUDL-SW computer analyses of 26 models of specific supports or assemblies of supports or by comparisons of other supports with 9 of the 26 specific supports or assemblies of supports which had been analysed.

Documentation of the comparisons is provided in tabulations in SWEC calculation ES.1090, pp.

ES.1100-ES.1111.

a.

Analysis of Specific Cases The inspection of the analyses of specific cases of cable tray supports included:

(1) a review of analysis Cases R1, R3, R6, and R10 to assess the scope of the analyses, (2) a review of analysis Case R3 to assess the implementation of the analysis and (3) a review of differential stiffness effects in supports.

The review of Case R1, R3, R6, and R10 found that the scope of analyses was adequate to satisfy the design requirements of the critical load combinations of Section 3.8.4.3.3 of the FSAR and Section 4.1.2 of the SDC.

These combinations were given in Equation 14 for Severe Environmental Condition and Equation 21 for abnormal / extreme environmental condition.

Specifically, the analytical inputs included the support configuration, member properties, weight data, peak acceleration data for OBE, SSE, SRV and CHUG loadings and temperature difference data.

Additionally, verification of compliance with design requirements for stresses in support members, welds, punching shear, bracing and connections were included in the analyses.

During the review of special analysis Case R3, the following deficiencies were identified in the implementation of the licensee's analyses for cable trays:

The first of these deficiencies was associated with the failure to detect dimensional discrepancies between the design of the supports as shown in the drawings and the design as shown in the analysis and with the dimensions of the computer models.

This failure to detect the dimensional discrepancies can be attributed to either inadequate checking or inadequate documentation of the use of engineering judgement, both of which represent inadequate control of design process.

Specific analysis Case R3 was found to consist of a pair of axially-braced trapeze supports (RB83A and RB84A) which were used for

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-g-comparison in the qualification of other supports.

Dimensional differences were found between the design as shown on the drawings (SWEC Drawings 12210-EE-340AE-3 and 12210-EE-340YY-4), the design configuration shown in the analysis (SWEC calculation ES.1300, p.

ES.1354) and the idealized STRUDL computer model which was analysed (SWEC calculation ES.1300, p. ES.1354). The licensee was requested to assess the impact of these dimensional differences on the design of the supports in Case R3 and other supports inside the RB.

The licensee responded by submitting the results of:

(1) reviews of dimensional differences between the design configurations shown in the analysis and the idealized computer models, and (2) reanalysis of three of the worst case differences identified.

Based on the results of these reviews and reanalysis, the licensee had concluded that the dimensional differences between the design shown in the analysis and the computer model utilized in the analysis had no impact on the design of seismic Category I cable tray supports inside the RB.

A review of the licensee's submittal verified the licensee's conclusion.

The review found that the reanalysis in Cases RA, R3A, and R14A for original cases R1, R3, and R14, respectively, assessed differences in support width of 52 inches vs. 33 inches, support length of 56 inches vs. 42 inches, respectively.

The results of the reanalysis indicated that the supports were in compliance with their design requirements.

The review also found that although differences between the current design configurations as shown in the drawings and both the design shown and the computer models utilized in the analyses were not specifically evaluated by the licensee's submittal, the results of the submittal can be extended to these differences since all the dimensional differences were of comparable magnitude.

The second deficiency was related to inconsistencies in the configuration of the cable tray hold down connections between the design drawing and the analysis.

This deficiency was attributed to inadequate control of the design process during the design of the connections.

The current design for the Case R3 connections was shown in Detail H of SWEC Drawing 12210-EE-340AF-2, " Seismic Cable Tray Support, Standard Details, Reactor Building," Revision 2, August 21, 1984.

Current designs for other types of cable tray hold l

down connections were also shown in Details J, K, and M of this SWEC

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drawing.

Analyses for these connection details were documented in SWEC calculation pp. ES.1483-ES.1494.

However, based on comparisons of the drawing and the analyses a deficiency relating to inconsistencies in the identification and configuration of the hold down connections between the drawing and the analyses was identified.

In particular:

(1) Details H, J, and K, in the analyses, were identified as Details l

J, K, and L respectively; (2) the flare bevel weld on the drawing was i

specified to be 13/4 inches long for drawing Detail H but was of l

unspecified length for drawing det.ils J and K; however, the l

corresponding flare bevel and welds were assumed to be 2 inches l

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-10-long in the analyses, (3) a bolt torque of 62 ft.-lbs to 67 ft-lbs

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was specified in the drawing but assumed to be 64 ft.bs. to 67

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ft.-lbs. in the analysis, and (4) the dimensions of tb slotted holes in the 3 x 2 x 5/16 angles shown in the drawing 1or drawing details H, J, and K was 9/16 in. x 1 3/4 in. maximum but were assumed to be 9/16 in. x 1 1/2 in, and 9/16 in. x 1 1/4 in in the analysis.

l An additional inconsistency identified in the analysis was that the material for the 1/2 in. diameter bolt was identified as both A35 and A325 material.

The third deficiency was related to inconsistencies in the analysis of the cable tray hold-down connection analyses.

This deficiency was also attributed to inadequate control of the design process during i

design of the connections.

These connections were assumed to be pinned connections in the STRUDL computer analyses thereby permitting the cable trays to be fully effective in transmitting axial forces between supports RB 83A and RB 84A.

As the consequence, the stresses

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in the supports due to loadings applied in the axial direction of the

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i supports will be reduced but loads will be induced in the connections

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by thermal loadings during accident conditions.

However, during I

verification of the adequacy of the connections, forces induced by l

thermal loads were ignored on the basis that slotted holes existed in the connections.

Omission of the calculated thermally induced forces

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in the connections was necessary to demonstrate compliance of loads

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on the connections with the limit of 2.85 kips established by SWEC.

The inspection found that the same type of connection was utilized in the supports analysed in cases R1 and R2 and that calculated thermally-induced loads in the connections were also ignored in these cases in order to verify compliance with the 2.85 kip limit.

The fourth deficiency was related to a discrepancy in the

documentation of the analysis and was also attributed to inadequate l

control of the design process.

Although the analysis was dated j

March 9, 1982 by the preparer, the computer analyses referenced in the analysis was dated August 18, 1982 (See Calculation p. ES.1358).

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Inspections of the referenced computer analyses, Job Nos. 706, 1790, and 4372, verified the referenced date of August 18, 1982.

A review of the analysis found that the apparent discrepancy in the dates did not affect the results of the analysis.

The four deficiencies listed above result from inadequate control of the design process and constitute a violation of 10 CFR, Part 50, Appendix B, Criterion III, Design Control (50-458/8509-01).

b.

Comparison Method of Design With respect to the comparison method of design of seismic Category I cable tray supports inside the RB, the inspection found that the

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g-11-method of design was uncontrolled and inadequately documented as described below and therefore constitutes a violation of 10 CFR, Part 50, Appendix B, Criterion III, Design Control (50-458/8509-2).

i The comparison method was described only in SWEC Calculation

No. ES.1090, p. ES.1097 wherein it stated only that, cable tray supports (inside RB) are qualified by either specific calculation or

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comparison calculation.

The comparison calculation method consists of determining the critical parameters of the actual support.

Then, utilizing

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engineering judgement, the previously completed specific calculations are examined to locate a design which is conservative in similarity to the actual support.

This conservative calculation then becomes the qualifying calculation.

This method of design was found to be deficient since the description did not provide guidelines for the identification of the critical

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support parameters and criteria for conservatism to be utilized in

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implementing the method.

I Additionally, the only documentation for the use of this method of l

qualification was provided by remarks in the tabulations pp. ES.1100

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and ES.1111 stating:

Similar to Case RXX, Calculation ES.YYY or

Similar to Calculation ES.XXX, pp. ES.YYY

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l Case RXX or Calculation ES.XXX being the specific calculation

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This documentation was found to be deficient since the basis for determining that supports were similar was not provided.

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l In view of the deficiencies identified in the comparison method of l

qualification, the licensee was requested to provide assurance that the cable tray supports inside the RB which had been qualified by this method were in compliance with their design requirements.

The licensee responded by submitting criteria for implementation in support of the comparison method of design (SWEC Calculation No. ES.1090, pp. ES.1112 - ES.1136, June 3, 1985).

As a result of the response, the licensee concluded that the comparison method of design was adequate.

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A review of the licensee's response to the deficiencies in the comparison method of qualification resolved the noted deficiencies.

i The review determined that the criteria developed for the method were adequate to ensure that the dynamic effects in the supports qualified

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-12-by the comparison method were less than those in the previously analysed specific supports utilized in the inethod.

Specifically, the criteria required that comparisons of support design parameters be conducted to assure that the natural frequencies of the supports qualified by the method were less than the natural frequencies of the previously qualified supports and that the effects of the mass of the supported cables and cable trays were less in the supports qualified by the method.

Effects of differences in the amplified response spectra due to the various dynamic loadings resulting from support location inside the RB were not addressed in the method but were found to be not necessary since qualification of the supports was

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based on the maximum drywell and steel containment response spectrum i

CalculationES.1090,pp.1057.1-1059.1)gerthan10Hz(See accelerations in the frequency range hig Additionally, differences

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in support orientation inside the RB were not addressed in the method but were also not necessary since the loadings on the specific supports analysed were considered to be applied in the worst manner; i.e., with the maximum horizontal accelerations transverse to the i

supports.

(The maximum horizontal accelerations inside the RB occur i

in the RB radial direction.) Furthermore, the static method utilized

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to evaluate the effects of differences in mass distributions in the supports qualified by the method was found to be acceptable since the static and dynamic effects of the mass distributions can be correlated for the dominant mode of response of the supports to the applied dynamic loads. The review also found that the criteria were implemented satisfactorily.

In general, the acceptance criteria were satisfied and deviations dispositioned on the basis of engineering judgement were found to be acceptable.

These deviations were generally associated with noncompliance with the criteria by negligible margins.

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5.

Design of Cable Tray Supports Outside the RB The inspection found that the 2273 seismic Category I cable tray supports outside the RB were qualified on the basis of:

(1) generic two-i dimensional analyses and multiplication factors to account for three-dimensional effects; (2) special calculations for specific configurations,

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and (3) the comparison method of design.

A total of 162 analyses were performed of which 85 pertained to generic designs and the remainder to special design configurations.

The 85 generic designs were utilized in the comparison method of design to qualify the 2273 supports.

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Typical natural frequencies of ca'i e tray supports inside RB and greater l

than 10 Hz.

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-13-A review was performed to assess the adequacy of:

(1) the scope of the analyses; (2) the implementation of specific analysis cases, and (3) the implementation of the comparison method of design.

The review of the 85 generic analysis cases found that the first 73 were performed to develop design guidelines for axial and transverse bracing and clear length to assure that the supports would respond rigidly during the critical, dynamic, seismic loading.

The analyses included parametric studies of the effects of the number of trays supported and the length and width of the supports on the dynamic response of the supports to the applied loading.

The remaining generic analyses were performed to assess the effects of other than dynamic loads on an as identified basis.

These loads included the weight of attachments to the supports addressed under the " load matrix" program and the additional weight due to fire wrap.

The review found that the generic analyses were performed using the design methodology contained in Procedures PTR-14 and EMTG-4A.

Both of these procedures were based on two-dimensional analyses with 20-3D factors applied to account for three-dimensional effects in support systems.

The design methodology of both PTR-14 and EMTG-4A were found to be acceptable but the basis for the 2D-3D factors presented in PTR-14 and EMTG-4A was not available.

This represents a violation of 10 CFR Part 50, Appendix B, Criterion III, Design Control (50-458/8509-3).

Subsequently, the licensee provided the results of an analysis which confirmed that the 20-3D factors were conservative.

This analysis was found to be acceptable.

The review of the analyses for the special design configurations found that the analyses were conducted in a manner consistent with those performed for the generic cases.

Overall, the review concluded that the inputs and method of analysis were found to be acceptable.

6.

Inspection of As-Built Configuration and Load Verification Programs The report of the Construction Appraisal Team (CAT) inspection conducted by the Office of Inspection and Enforcement (IE) on July 30 through l

August 10, and August 20-31, 1984, lists, in Appendix B, potential enforcement actions based on the NRC CAT inspection observations.

The CAT j

report was referred to this office (Region IV) for review and appropriate enforcement action.

Appendix B, Potential Enforcement Action, Item 2.a l

j identifies a potential failure to verify the adequacy of design in that load calculations for the RB cable tray supports were based on design l

information which did not represent the as-built configurations.

NRC, CAT l

inspectors identified several supports which contained horizontal members

whose lengths exceeded the dimensions shown on the tabulation drawings.

The tabulation drawings detailed the design dimensions which were to be

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follcaed during the installation of the supports and which were used for seismic loading calculations.

Due to the congestion inside the RB, field fabrication of cable tray supports became necessary and was anticipated by establishing an as-built walkdown and documentation review at the completion of construction.

The time frame of the CAT inspection was premature in addressing the implementation of Stone & Webster's program for inspecting and documenting cable tray supports.

The NRC CAT inspectors concluded that as-built verification of all RB cable tray supports and seismic analysis of those found to be out of tolerance was required to determine that RB cable supports were constructed in accordance with seismic loading limitations.

It was determined during this inspection that this verification of design was initially planned and subsequently completed.

Stone & Webster Specification No. 248.000, Revision 8, " Electrical Installation," Section 6, " Field, Quality Control Program," Item 6.2.2.2.b required visual inspection to assure the correct installation of raceway system supports.

The specification also required that all supports attached to Category I steel utilizing any form of welding other than stud welding, have 100 percent visual inspection of the base metal after welding.

Deviations between as-installed support configurations and the design requirements are required to be documented along with the engineer's disposition of such deviations.

This requirement is delineated in Engineering & Design Coordination Report No. C28111 as a modification to Specification No. 248.000.

In the context of the specification, support configuration referred to the following attributes:

support loads and spans, member size and length, weld size and length, and bolting and attachment hardware.

Additionally, an engineering representative visually checks all Category I supports to assure that they were installed in accordance with all other attributes of the applicable drawings.

The field quality control inspection and documentation program for cable tray supports inside the RB was delineated in quality control instruction No. FRI-D14.1-05C, " Raceway and Support Documentation."

The procedure which establishes the method for verifying that conduit support loading and loading on the cable trays due to conduits and other attachments are within the allowable limits shown on the engineering drawings was delineated in Construction Site Instruction No. 9.0.21, Revision 1, " Conduit Support Load Verification." The implementation of these procedures was reviewed during this inspection along with the resulting Engineering & Design Coordination Reports which documented deviations from the design documents.

Structural Engineering Procedure No.106.9A, " Engineering Evaluation of Electrical Raceway and Supports,"

defined the requirements for the engineering evaluation of the as-built electrical raceway and supports in conjunction with construction completion and field quality control inspection and acceptance.

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-15-The loads imposed on the structural steel beams from attached cable supports and conduits were taken into account in SWEC Structural Design Verification Program.

This program, delineated in " Procedure for Structural Load Verification," November 7,1983, was reviewed during the l

NRC inspection conducted at the CHOC.

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Calculation No. MC 801.1, " Generic Loads For Cable Tray And Conduit Supports For Load Verification," provided the generic loads for cable tray and conduit supports used in the structural load verification.

To account for loads existing on structural members, the calculation generically analyzes the resultant moments and forces in the three principal axes.

The analytical basis of the structural design verification program was to assume that the additional load imposed on the structural steel was equivalent to the maximum load capacity of the connection between the support and the structural steel.

Calculation No. MC 802.1, " Load Verification, Connection Check Procedure,"

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prescribes the technique utilized to check structural steel beam end connections and supplemental steel to main beam connections subjected to multi-directional forces.

The effects of torsion on connections are analyzed by reducing the torsional loac. to an equivalent vertical end reaction.

This equivalent load is then added to the end reaction due to additional vertical loads.

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As a result of this inspection, it was verified that programs for

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inspecting, documenting and evaluating as-built cable tray and conduit supports and resultant loads on structural steel were in existence.

In addition to the inspection of the licensee's as-built configuration and load verification programs, a walkdova inspection of the seismic Category I cable tray support installed inside the RB was conducted to verify the implementation of the as-built verification program.

This walkdown inspection identified two deficiencies relating to inadequate i

disposition and documentation of construction deviations.

These two items

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constitute a violation of 10 CFR, Part 50, Appendix 8. Criterion XV, Nonconforming Materials, Parts, or Components (50-453/8509-04).

The first deficiency was related to the cable tray hold down connection for the cantilever type support RB 195C.

SWEC Engineering & Design Coordination Report (E&DCR) C-24.199 identified that the cable tray was

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sloped at support RB 195C and requested a design for the hold-down

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connection, however, the slope of the cable tray was not specified in the E&DCR.

The approval of the E&DCR contained only a sketch of the i

connection.

The sketch was not dimensioned and no supporting calculations were provided.

The connection shown in the sketch was similar to that in j

DegailJgfSWECsupportstandarddetaildrawing12210-EE-340AF-2 fora

30 or 45 sloped connection for the trapeze type supports rather than for a cantilever type support.

The licensee was requested to provide an

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-16-adequate basis for approval of E&DCR C-24.199.

Subsequently, the licensee submitted E&DCR calculation pp. 28-29 in response to this request.

The calculation was based on dimensions included in the submittal and concluded that the support, as constructed was adequate to sustain the torsional moment induced in the support due to the eccentricity of the hold-down connection.

A review of the licensee's submittal concluded that the calculations provided an acceptable basis for approval of E&DCR C-24.199.

The review found that the original analysis for Support RB 195C was based on TS 5 x 3 x 3/8 structural member but that the current design specified a TS 6 x 6 x 1/4 member.

The larger TS 6 x 6 % member was adequate to sustain the torsional moment induced by the eccentric hold-down connection.

The second deficiency was related to the internal members for the trapeze type support RB 29AS.

SWEC Drawing 12210-EE-340 AA-5 indicated that two internal dummy members were incorporated in the design similar to the Type II internal member configuration shown in SWEC Drawing 12210-EE-340 AE-3.

The walkdown inspection determined, however, that the as-built configuration incorporated instead diagonal bracing members similar to those shown in the elevation view in the SWEC standard detail drawing 12210-EE-340 AE-3 for trapeze type A and Al supports.

Subsequently, it was determined that the two dummy members have been identified as missing during the installation inspection of the support in May 1985 and reported in nonconformance and disposition report (N&DR) 11957 in June 1985.

The disposition of this N&DR required that the reported missing dummy members be replaced by special internal cross bracing similar to that for installation in support RB039A.

An NRC review of calculation pp.59-598 for E&DCR C24317 found, however, that the E&DCR related to modifications to cross bracings existing in the original design of support RB 039A and not to the replacement of horizontal internal members by cross bracing.

The review concluded that modifications addressed in E&DCR C24317 for support RB 039A were not similar to the modifications specified in the disposition of N&DR 11957 for support RB 29AS and therefore, that N&DR 11957 was improperly dispositioned.

The licensee was requested ta evaluate the as-built configuration of support RB 29AS for acceptability.

The licensee responded to this request by submitting an analysis which verified that the as-built configuration was acceptable.

A review of the licensee's submittal confirmed the results of the licenses's analysis.

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Exit Interview The NRC inspector met with licensee representatives at the conclusion of each inspection period.

The NRC inspector summarized the scope and I

findings of the inspection.

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