IR 05000338/1987016

Insp Repts 50-338/87-16 & 50-339/87-16 on 870608-11.No Violations or Deviations Noted.Major Areas Inspected:Review of Selected Reactor Engineering Procedures & Completion Status of Previously Identified Insp Findings

ML20235U022
Person / Time
Site:	North Anna
Issue date:	07/13/1987
From:	Lawyer L, Long A, Shymlock M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20235T990	List: IR 05000338/1987016 ML20235T988
References
50-338-87-16, 50-339-87-16, NUDOCS 8707220332
Download: ML20235U022 (17)

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UNITED $TATES

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[kB Rf og% .,, NUCLEAR REGULAYORY COMMISSION e p( REGION il 5 a g- 101 MARIETTA STREET, N.W., SUITE 2000

• f o ATLANTA, GEORGIA 30323

%, .... / 1 Report Nos.: 50-338/87-16 and 50-339/87-16 Licensee: Virginia Electric and Power Company Richmond, VA 23261 Docket Nos.: 50-338 and 50-339 License Nos.: NFP-4 and NFP-7 Facility Name: North Anna, Units 1 and 2 Inspection Condu ed: J ne 8- 1987 Inspectors: / 0 L ' Law r orfngineer Date Signed

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7/n/G 7 A. R. Long Reactor g(gineer ' Dat'e Signed Approved by: 2 M. b'.

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Shymlock, Section Chief V A 7 Date

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//7 Operational Programs Section Division of Reactor Safety SUMMARY Scope: This routine, announced inspection involved the review of selected Reactor Engineering Procedures and the review of the completion status of previously identified inspection findings in the training and maintenance area Results: No violations or deviations were identifie PDR ADOCK 05000338 G PDR

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P REPORT DETAILS PersonsLContacted Licensee Personnel:1 H ' *E. ' W. : Harrell, Station Manage *M..L. Bowling, Assistant Station Manager W. B. Buchardt, Mechanical Maintenance Procedure Writer

"i. D. Crist, Senior. Instructor, Nuclear

• R.^ U. Driscoll,' Manager, Quality Assurance

' *L. L,.- Edmonds, Superintendent, Nuclear Training .

R.1G. Jones, Quality Control Supervisor'

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. *G.-G. Harkness.-Licensing Coordinator I

• E. S. Hendrixson, Reactor Engineer

- *J. ' H. - Leberstien. Engineer

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Other licensee' personnel contacted included engineers, office personnel, and security officers.-

NRC Personnel: .

L.- King, Resident Inspector

• Attended Exit Meetin . Exit Meeting The inspection scope andLfindings were summarized on June. 11', 1987, with those persons indicated in paragraph I above. The inspector' described.the areas inspected and discussed in detail the inspection findings, including the closure of the' items listed belo No dissenting comments were received from the license ITEM NUMBER STATUS DESCRIPTION / REFERENCE PARAGRAPH UNR 338,339/84-41-06 Closed Replacement of -Category I System Components with Category II Parts (Paragraph 3)

'IFI 338,339/84-39-01 Closed Implementation of the Performance Based ProgramOp(erator ParagraphLicense 5.a) Training IFI 338,339/84-39-02 Closed Implementation and Submittal to the NRC of the New Requalification Program (Paragraph 5.b)  ;

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IFI 338,339/84-39-05 Closed Shift Duty for Backup Licenses and Instructors (Paragraph 5.b)

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p IFI 338,339/84-39-03 Closed Mak'eup Systems Training for Seven Non-Licensed Operators (Paragraph -

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l IFI 338,339/84-39-04 Closed- Implementation. of Instructor Certification Program '(Peragraph 5.d).

H IFI 338,339/84-39-08 Closed Implementation. of Engineer-Training Program (Paragraph 5.e)-

'IFI 338,339/84-41-01~ Closed Incorporation of Standing Devia-tions and Step Completion Dates into Maintenance Procedures (Paragraph 5.f)

IFI 338,339/84-41-02 Closed Guidance for Establishing Quality Control Hold Points, and Specifi Training for Procedure Writers-(Paragraph 5.g)

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The licensee'did'not identify as proprietary any'of the materials provided to or reviewed by the inspectors during the inspectio . Licensee. Action on Previous Enforcement Matters (92702)

(Closed) Unresolved Item 338,339/84-41-06: Replacement of Category I System Components with Category 11 Parts Background:

Licensee Administrative Procedure ADM-2.1, Attachment II, classified  !

certain plant structures, systems and components as Category I. Category I components were defined in procedure ADM-4.0 as those whose failure could release radioactivity that would endanger public safety, whose purpose is to mitigate the effect of such failure, or which are required for safe ,

operation, shutdown, and removal of residual heat. Procedure ADM- defined Category II systems as those components which are essential to power generation, whose failure could be hazardous to station personnel, or which contain radioactive materials but not in quantities sufficient to

. endanger public safet A maintenance supervisor had indicated to NRC inspectors that some parts of Category I systems were being replaced with Category 11 part Resolution:

Procedure ADM-4.0, Procurement Document Control, has been revised to define Nuclear Plant / Safety Related and Nuclear Plant /Non-Safety Related in the same terms by which Category I and Category II were defined in the previous revision. Certain components of safety related systems which j

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could fail without degrading the safety related function of the system (gaskets, packing, etc.), have been classified as Nuclear Plant /Non-Safety Related. The procurement and replacement of these designated and con-trolled parts is treated accordingly. This appears to be well controlled and documented, with adequate engineering calculations to justify the classification The licensee stated that when components classified as Nuclear Plant /

Safety Related are replaced with equipment classified as Nuclear Plant /

Non-Safety Related, two mechanisms may be used to initiate and document

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engineering review and approval of the substitution. A Commercial Quality Evaluation Form may be completed to document the engineering review and any testing which is require Engineering evaluations of part substitu-tions may also be requested and documented on Engineering Work Requests when questions of material quality arise during maintenance function Based on the above information, this item is close . Unresolved Items No unresolved items were identified durir.g the inspectio . Licensee Action on Previous Inspector Followup Items (92701) (Closed) Inspector Followup Item 338,339/84-39-01: Implementation of the Performance Based Operator Licer >e Training Program Background:

NRC inspectors had identified the lack of a controlling license training program document, which had possibly had a detrimental effect on operator license examination performance. At the time of NRC Inspection 338,339/84-39, the licensee was in the process of implementing a new Performance Based License Training Progra Systems texts and lesson plans were being update l Resolution:

l The following items were reviewed by the inspector and found to have been reviewed and approved by training, operations and corporate management:

, Reactor Operator License Course Program Guide, September 1985 Licensed Operator Requalification Program Guide, March 1985 Shift Supervisor Training Program (undated)

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The. above documents control the program for licensed operators by specifying)the program's goals and program entry requirements (pre-management of the program, and by delineating the program' content and instructional method, the method of evaluation of both the trainees l and the program, and the documentation of results. The program is performance based as evidenced by the performance orientation of the l goals stated in each progra The inspector verified that the 1979 lesson plans and systems texts have been rewritten and revised. One lesson plan and one system text were selected at random (Residual Heat Removal) and reviewed in detai Both of these documents represented substantial improve-ment over the previous material in its organization, accuracy and completenes Both documents reviewed in detail were satisfactor They have incorporated both terminal and enabling objectives. Utili-zation of these training materials has apparently contributed to a very successful Licensed Operator Training Program. .The last licensed operator training class consisted of five R0 and three SR0 candidates who passed the company screening and were put up for NRC administered examinations. All of these candidates passe Based on this information, the item is close (Closed) Inspector Followup Item 338,339/84-39-02: Implementation and Submittal to the NRC of the New Requalification Program (Closed) Inspector Followup Item 338,339/84-39-05: Shift Duty for Backup Licenses and Instructors Background:

At the time of NRC inspection 338,339/84-39, licensed staff personnel could be exempted from a year of requalification training based on annual requalification examination hores of greater than 80%. The licensee was then in the process of implementing a new Licensed Operator Requalification Program (LORP), which would require that all licensed individuals attend requalification training except where excluded from specific lectures per 10 CFR 55 Appendix A. In addi-tion, the new program was to require that all personnel, including training staff and backup licensees, who were to maintain their licenses active, would spend at least five days per quarter on shift performing licensed duties. Licensed personnel who did not meet this requirement were to have their licenses declared inactiv Resolution:

The Licensed Operator Requalification Program has been implemented as required. It was NRC approved on March 30, 1984. The new program does not allow exemption for licensed staff personnel based on scoring 80% or greater on the previous requalification examination.

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The new LORP requires 'that all licensed. individuals attend' requali-fication training except where excluded from specific lectures._ All personnel, including . training staff and backup licensees, who are to maintain their licenses active, will . spend at least.five shifts (40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br />) per quarter on shift performing . licensed dutie Based on this'information, these items are close (Closed) Inspector Followup Item 338,339/84-39-03: Makeup Systems Training for Seven Non-Licensed Operators Background:-

Seven of a group of nine non-licensed operators did not atten systems . training due to manpower requirements of a plant outag Additionally, NRC inspectors ' had commented that systems training -

. courses for non-licensed operator training were not designed specifi-cally for operators, and had observed a course being taught under crowded conditions. . Systems texts for non-licensed operator training were in the process of being brought up to date at the tine of inspection 338,339/84-3 Resolution:

The inspector reviewed eight systems training lecture attendance sheets. representing the _ attendance of the five reactor operators who completed the most recent licensed operator training class. All students attended six of the eight lessons. Only one student missed

.each of the other two lessons. Based upon this, the poor attendance problem seems to have been resolve The systems texts have been upgraded as discussed in the resolution of Inspector Followup Item 84-39-01 (Paragraph 5.a). In addition', the texts have been developed specifically for use in training operator The inspector observed a non-licensed operator training class in session. Candidate spacing was adequate and other environmental conditions were conducive to learnin Based on this information, the item is close (Closed)InspectorfollowupItem 338,339/84-39-04: Implementation of Instructor Certification Program Background:

At the time of NRC Inspection 338,339/84-39, the Instructor Certifi-cation Program was in transition to a performance based progra The previous program consisted- of training and evaluation by the Training Supervisor. The new program was to consist of a seven day

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basic section, and a two year supervised self-study Master Instructor Certification Module. Monitoring of:the progress of the new program

.was identified as an inspector followup ite Resolution:

The inspector reviewed " Instructor Training / Certification Program" dated November 1,'1986, which described the licensee's performance :

based : instructor training / certification program.. It has been imple-mented with all' 38 instructors having completed' or' waived the. Basic Training ' Program except for four new instructors and one instructor who' developed and was teaching the course. The remaining 33 instruc-tors were all. enrolled in the advanced Training Program and had completed an average of seven to eight of the 23 units.. This ad-vanced course was required to be completed within three years of the date of enrollment or date of- completion of the Basic Training Progra Based on this information, the item is close While progress appeared to beLsubstantial, the inspector noted that in some cases an accelerated effort would be required to meet the Instructor Certification Program requirement for completion in three l

' years. This conclusion was based on reviewing the unit completio ~

record.: There were 13 instructors who entered the program 1n Decem-ber 1984 and therefore should complete it by December 1987. As of April 1,1987 these 13 instructors had a minimum of nine units and a maximum of 17 units yet to complete. In the extreme case this will require completion of about two' full units per month - a completior rate far in excess of the past average. This concern was brought to the attention of licensee managemen In addition, the qualification of two instructors were reviewed in !

detail and compared to the requirements of the " Instructor Certification Training Program Guide," Revision 2 dated November 1, 198 No discrepancies were note (Closed) Inspector Followup Item 338,339/84-39-08: Implemen+2 tion of Engineer Training Program Background:

At the time of NRC Inspection 338,339/84-39, the licensee was in the process of developing a formal training program for engineer Implementation of this program was to have included attendance criteri l l

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Resolution:

The licenses has implemented a formal training program for engineers entitled Nuclear Power Station Engineer Training Program (NPSETP) and Nuclear Power Station Engineer Continuing Training (NPSECT) Program, which is described in a similarly titled Program Guide, Revision 2, April 1987. The NPSETP consists of a three-month basic course and a roughly 18 month specialized course. Both prerequisites and atten-dance requirements are specified in the approved Program Guid The individual training records for three randomly selected engi-neers, one each from Plant Engineering, Inservice Inspection and Nuclear Safety Engineering, were examined and all three demonstrated that the NPSETP has been implemente Based on this information, the item is close f. (Closed) Inspector Followup Item 338,339/84-41-01: Incorporation of Standing Deviations and Step Completion Dates into Maintenance Procedures (1) Incorporation of Standing Deviations Background:

Licensee administrative procedure ADM-5.8 stated that procedure deviations made due to unforeseen changes shall normally be applicable only to a specific one time use of the procedur NRC inspectors had identified that procedure deviations on certain welding procedures had been applied over an extended period during an outag Resolution:

Station Maintenance Welding Procedures were completely rewritten and all outstanding deviations were addressed in the revision The revised procedures were approved by the Station Nuclear Safety and Operating Committee (SNSOC) on July 25, 198 The inspector checked all current welding procedures for outstanding deviations and there were non Procedure ADM-5.8, Temporary Changes / Procedure Deviations, Revision dated September 25, 1986, allows application of a single deviation to repeated performances of a procedure provided it is reviewed by SNSOC and approved by an Assistant Station Manager. The inspector randomly selected and reviewed I a number of deviations in the Mechanical Maintenance, I&C, and Surveillance and Testing Files. Procedures approved for -

repeated use indicated the time period over which they were I

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' va' lid. No' examples were' identified where the Deviations were not. approved before use :when the intent of the ' procedure was changed, or where the Deviations were not approved by SNSOC within 14 calendar days per ADM- A number - of Deviations in the:I&C. files' were-identified by L the inspector to be_ outdated.: Each 'of these Deviations = was then verified by the licensee to have been . incorporated into permanent, procedure revision ' ADM-5.8 states that persons -

using procedures should initiate the steps to: verify th resolution of outstanding' deviations.. against the procedure .

. and remove invalid: Deviations from the files. This netter was brought'to the attention of licensee managemen Additionally, numerous Deviations. in the I&C files 'and two.

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l Deviations in the Surveillance:and Testing files did not have the implementation date entered as required by ADM-5.8. This L

also was brought to the- attention of licensee management. The

_ missing implementation dates could be inferred from the dates of'

the other. signatures on the form Licensee- personnel told the' inspector 'that Mechanical Mainte-nance was considering implementing a serialized computer track-

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ing system for procedure deviations. The inspector, concurred that such a' system would be'very beneficia (2),IncorporationofStepCompletionDates-Background:

The licensee permitted steps in procedures to be reperformed (procedure re-entry). This made it difficult to determine if and when a maintenance step was- satisfactorily completed. An example had been identified by NRC inspectors where certain steps of a procedure had been reperformed_ yet the steps were only initialed once. The inspectors had also observed that many steps in maintenance procedures did not require the recording of the completion dat I Resolution:

The licensee revised the Mechanical Maintenance procedures to state that sections of the procedure may be re-entered as required to ' correct deficiencies prior to job completio Quality Control is to be notified if procedure re-entry is required. Re-entry sign-offs are to be entered on the back of the appropriate page.

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F 9-The inspector reviewed a random selection of Mechanical Mainte-nance procedures and verified that they provided for re-entry .

I when necessary and that they adequately provided for recording ?

L step. completion dates. The inspector alsc reviewed implemen- ;

I -tation of the re-entry ' sign-off requirements in a number of- t randomly selected completed Mechanical. Maintenance procedure No problems were' identifie '

(3). Procedure References Background:

The reference sections of numerous-licensee maintenance proce-dures had included vague references such as " applicable manufac-turer instruction manuals, prints, and drawings" or " applicable

' station administrative procedures". An inspector concern had been expressed to the licensee that such vague references were of limited use to the' individual performing the maintenanc Resolution:

The licensee has been systematically reviewing procedures and clarifying and updating references .where appropriat Their required biennial procedure review includes human factor considerations such as adequate . references, in addition to technical consideration Various procedural controls specifically require adequate refer-encing. The Procedure Review Checklist in Procedure ADM-5.4, Processing New and Revised Procedures and Deletion of Proce-dures, March 13. 1987, includes a review and sign-off that procedure references are correct and current. Procedure ADM-5.3, Review of Procedures,. March 31, 1987, requires biennial procedure reviews which are to ' include human factors as well as .

technical considerations. The procedure requires the reviewer l to verify that references are adequate and contain the latest ,

approved revisions. ADM-5.3 also includes a human factors checklist as Attachment 6.1. The inspector noted that. Guide-lines for Writing and Reviewing I&C Procedures, datJ November 6, 1986, states requirements for what information must be included in a procedure referenc The inspector reviewed the Reference Sections of a random selec-tion of procedures for Mechanical Maintenance, for Surveillance and Testing, and for Instrumentation and Controls. No examples of inadequate references were identified. Certain generic proce-dures continued to include very general references, which the i

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inspector concurred were appropriate for that applicatio Based on the information above, the item is closed.

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10 (Closed) Inspector Followup Item 338,339/84-41-02: Guidance for Establishing Quality Control Hold P0ints, and Specific Training for Procedure Writer Background:

NRC inspectors had expressed a concern regarding Quality Control (QC)

hold' points in maintenance procedures. In particular, for one Work

. Request reviewed by the NRC, there had been no QC involvement to ensure that all objects were removed after work was completed on an open safety-related system. The inspectors had not been able to locate specific station procedural guidance regarding_ the establish-ment of QC hold points, and expressed concern that procedure writers were not receiving formal trainin Resolution:

The licensee began conducting specific training for Maintenare Department procedure writers in 1986, as documented in the internal memorandum from R. E. Sidle to M. R. Kansler dated December 3,198 The training includes writing skills and systems training, using plant-specific reference material. In addition, procedure writers ,

are required to attend the Maintenance Department's continuing 1 training in order to stay abreast of industry problems and new information. This training also addresses changes in administrative procedure and routine. Procedure writers are also to be included in I all routed required reading for Maintenance Department personne The licensee has implemented administrative procedures governing l procedure writing. The inspector reviewed MD ADM-27.0, Maintenance i Department Administrative Procedure Preparation and Content of  !

Maintenance Procedures, June 26, 1986; P&T ENGR ADM-10.0, Periodic Test Procedure Writing Guide, December 11, 1986; and Memo from R. A, Bergquist to Instrument Department Personnel, Guidelines for Writing and Reviewing I&C Procedures, November 6,1986. The guidelines were found to be comprehensive, and no problems were identifie Procedure ADM-5.3, Review of Procedures, and the various departmental writing guides all include requirements that adequate Quality Control hold points be included in procedures. Procedure ADM-10.3, QC Hold /

Verification Steps, August 1,1985, defines QC holds and verifica-tions and provides instructions on performing steps appearing in procedures.

l There is no formal procedural guidance on determining when QC holds j are required, and the procedure writer training program does not l

include the placement of hold points. This training is on-the-jo !

Procedure ADM-5.4, Processing New and Revised Procedures and Deletion l l

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of ~ Procedures, requires that' all new and revised safety related procedures be. reviewed by~ Quality Control. It is the responsibilit of Quality Control to ensure that adequate hold points have been

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include The inspector discussed with the QC Supervisor the specific question of procedural QC hold points for cleanliness checks after. work is performed on safety-related systems. The licensee's policy is to conduct adequate QC housekeeping surveillance so that a hold point-is not necessarily required after the work. is completed. Hold points for final cleanliness checks are' considered on a case-by-case basis based on experienc Although there is no formal procedural guidance prescribing when to establish QC hold points, the training and qualifications of QC personnel appears adequate to ensure that necessary QC holdLpoints will be establishe Based.on the above information, the item is close . Unit 2 End-of-Cycle Moderator Coefficient Measurement Anomaly (61708)

The inspector reviewed the results of Unit 2 End-of-Cycle Moderator Temperature Coefficient (MTC) testing at Hot Full Power, and the engineer-ing analysis which resolved apparent anomalies in the dat Technical Specification 3/4.1.1.4.b ' requires that the Hot Full Power-(HFP) MTC be less negative than -44 pcm/ degree F. The HFP MTC must be measured when the HFP critical boron concentration' reaches 300 ppm. If the measured MTC at 300 ppm is more negative than -33 pcm/ degree F, the-MTC must be remeasured every 14 days until the critical boron concentra-tion reaches 60 ppm. Performing the test becomes difficult at soluble boron concentrations below 60 ppm. If the measured MTC at 60 ppm is less negative than -40 pcm/ degree F, then the measurements may be suspended. .

Otherwise, the measurements must continue and the unit may not be able'to continue operation longer than another 14 EFP The HFP E0C MTC test methodology determines the coefficient from the j change in boron concentration between stable conditions at two tempera-tures. The reactivity worth of the boron change, accounting for any other i reactivity changes' occurring during the test, is divided by the tempera-l ture change to obtain an Isothermal Temperature Coefficient (ITC). The Doppler Coefficient is subtracted from the ITC to obtain the MTC. MTCs l are determined during the heatup and the cooldown portions of the test, and the average of the two values is compared to the trigger limits of the Technical Specification )

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The ' 300. ppm HFP MTC. for Unit 2 Cycle 5 was measured on March 16,.1987, .l

.to- be -33.2' pcm/ degree F, necessitating continuing measurements every 14 EFPD. Five such additional MTC measurements were performed as required;

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the final of which was' performed on May 20, 1987, at an average boron concentration of 68 ppm. The average MTC for the 68 ppm test was -4 pcm/ degree F, which did not meet the Technical Specification criterion for discontinuing the biweekly surveillanc .

The licensee observed larger differences. than expected between the heatup and.cooldown portions of the MTC tests and excessive scatter between 'j the tests on different dates. Interestingly, on some tests the heatup portion >of the test gave significantly more negative results, while on other tests the cooldown results were significantly more negative. A trend was observed between the degree of deviation from the prediction and the length of the tes These observations suggested that more than normal test uncertainty was involve The inspector reviewed completed test procedure 2-PT-13, Moderator Temper-ature Measurement at Power, performed May 20, 1987 at 68 ppm. The MTC measured on the' cooldown portion of the test was -40.75 pcm/ degree F, versus a heatup MTC of -46.31. No problems in the test data or analysis were identifie Average core power remained essentially constant throughout . the test,. so no Doppler or xenon' corrections were necessar A temperature change of approximately five degrees F and boron changes of 20-30 ppm minimized test errors attributable to the uncertainty in measuring these two' parameter The inspector considered the test performance and controls to be better than averan The licensee Nuclear. Engineering staff investigated the measurements using the FLAM3 computer model to evaluate transient reactivity effects which occurred during the measurement that were not part of the Moderator Temperature Coefficient. This study is documented in Technical Report N , entitled Xenon Correction Factors for N2C5 Full Power MTC Measure-ments, dated June 2,198 The report contains a description of the methodology used in the study and the corrections derived for the measured MTC values for each of the six HFP MTC measurements performed for Unit 2 Cycle Planning to minimize measurement uncertainty, the licensee had conducted unusually lengthy MTC measurements to obtain large changes in the boron and temperature parameters. The engineering analysis of the test results identified that the lengthy testing induced the following reactivity effects which accounted for the observed anomalies: The temperature dependence of the xenon absorption cross section resulting in lower xenon concentrations during the reduced temperature portion of the test Small but apparent depletion effects when the heatup and cool-down were not of equal length

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13 Larger . measured and predicted axial power shifts during the transient MTC tests .than in the static' MTC calculations, driven by the temperature dependence of the xenon cross section as well as prompt temperature feedback effects-In - general, shorter tests had smaller correction factors, while' longer tests had larger correction factors. Due .to the effects of the axial xenon

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distribution on the measured MTC, the timing of the two phases of the test is important in determining the degree to which. the xenon burnout, fuel depletion, and axial xenon redistribution effects cancel out or reinforce each other in the MTC results. This . explains the observation of more negative cooldown MTCs for some tests and more negative heatup MTCs for others. The length of each portion of the test and the size of the initial axial imbalance (proportional to the temperature swing and MTC) will determine the magnitude and timing of the axial xenon transien The FLAM3 simulations, generally, well predicted the behavior of the test dat Based on .the simulations, correr tions were' developed and applied to the measured. data to account for the transient effects. This resulted in greatly reduced scatter in the data and improved agreement with the predictions. The FLAM3-adjusted measured data were adopted as the official test results for the MTC test at 68 ppm through a Deviation to procedure PT-13 to justify continued operation without additional MTC testin Even with the inclusion of measurement uncertainties, for the adjusted data neither the '-33 pcm/ degree F trigger limit at a 300 ppm boron concentration or the -40 pcm/ degree F trigger limit for 60 ppm was reache In addition, no intermediate test point violated the -4 pcm/ degree F trigger limit. This indicated that no violation of the -44 pcm/ degree F most negative MTC limit would occur during the cycl ,

Within this area, no problems were identifie . Reactor Engineering Procedure Review (42700) Estimated Critical Position Estimated critical rod positions may be calculated for North Anna either manually, or using the ECP computer code. The inspector reviewed procedure 2-0P-10 Estimated Critical Position, Revision 9, September 25, 1986. No problems were identifie The ECP code allows more precise calculations than are feasible to perform manually. The inspector reviewed the documentation of the ECP code presented in N0D-CCR-1006, Revision 0. ECP An Automated Estimated Critical Position Calculation and Shutdown Margin Calcula-tion; and the enclosed VP-NOS-19, Revision 2, ECP An Automated Estimated Critical Position Calculation User's Guide. The code calculates estimated critical conditions based upon a previous critical condition statepoint, a detailed power history, and cycle-specific design data. Xenon is calculated from an input power history, rather than estimated from curves as in the manual metho The code output is in procedural format, including signoffs.

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The reactor engineer gave the inspector a demonstration of the ECP code, and stated that estimated critical conditions computed usin the code have usually agreed with the actual conditions at critical-~

ity within about 100 pcm. The administrative limit in the ECP proce-dure is plus.or minus 400 pc ECP 'is an. IBM- Personal Computer compatible- program which is con-trolled by the corporate Nuclear Operations Department and .is' not modified by plant personnel. A three-layer security system is

! 1mplemented to prevent alteration of executable-files or data file Shutdown Margin-The inspector reviewed periodic. test procedure 1-PT-10, Determination of Shutdown Margin, dated January 8,1987, which is used to verify that' shutdown margin is equal to or more negative than -1.77 percent delta k/k as required by. Technical Specifications and/or that Keff is less- than 0.95 prior to entry' into Mode 6. No problems,were - !

identified with. this procedure. The inspector noted that the proce- :

dure Indicated the direction of conservatism for the parameters used '

in the calculation Shutdown margin may also be calculated using the Shutdown option of the ECP code. The inspector reviewed the documentation of Shutdown in VP-NOS-27, Revision 1, which is an addendum to the ECP User's Guide (VP-NOS-19). No problems were identified. Shutdown .uses the cycle-specific data ~ stored in ECP, information from entered or stored previous critical conditions, plus.an entry for minimum expected RCS temperature. The calculation performs an iterative process so that the boron concentration used in calculating the hot-to-cold tempera-ture defect is the same as the shutdown boron concentration. Xenon worth may be set te zero to obtain conservative calculations for an outage, or may be calculated from the power history. The program output for North Anna is in a format compatible with procedure PT-1 Moderator Temperature Coefficient at End of Cycle, Hot Full Power The inspctor reviewed procedure 2-PT-13, Moderator Temperature Coefficient Measurement at Power, January 30, 1987. No problems were identified with either the test methodology or the procedural control Effective January 30, 1987, the licensee began using enthalpy weighted average temperature in the Moderator Temperature Coeffi-cient (MTC) test procedure. The inspector reviewed a Calculational Worksheet document entitled Calculational Basis for PT-13, dated January 27, 1987, and the attached memorandum entitled Enthalpy Averaged Vessel Tave for HFP MTC Tests North Anna Unit 1 and Unit 2, NP-424, NP-425, dated January 16, 198 l l

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The enthalpy averaging method is based on energy conservation and is consistent with the methods used in the licensee's codes for design report predictions and safety analysis calculations. Vessel average moderator temperature values used in MTC measurements were previously the numerical average of the measured hot and cold leg temperature The enthalpy averaging method defines the vessel average temperature as the temperature which corresponds to the average enthalpy in the vessel, and is calculated by numerically averaging the hot and cold leg enthalpies and then converting to average temperatur Results from the two methods differ at HFP because the relationship of temperature and enthalpy is not linear in the range between vessel inlet and outlet conditions. The temperature averaging method under-predicts the temperature change during MTC tests, and therefore i overpredicts the MT Using enthalpy weighted average temperatures in MTC testing at EOC can provide additional- margin from the Technical Specification limit The licensee's January 1987 memorandum stated that for.the Unit 2 Cycle 4 E0C MTC measurement, using the enthalpy averaged temperature change resulted in a 2% less negative MTC. The licensee also showed the inspector data for an E0C MTC measurement for Unit 1 Cycle 6, where using enthalpy averaged temperature decreased the measured MTC from -32 to -31 pcm/ degree Within this area, no problems were identifie . Burnable Poison Assemblies Loading Deviation Reports Review (92700) Deviation Report 87-495 Deviation Report 87-495, dated May 13, 1987 documented that four fuel assemblies scheduled for loading in Unit 1 Cycle 7 were found to be loaded with burnable poison rod assemblies (BPRA's) which had already been used in two previous cores. The reuse of twice burned BPRAs may result in swelling of the BPRA clad and mechanical binding to the fuel assembl The Cycle 7 core design called for the four fuel assemblies to contain previously burned BPRA's to achieve reduced peaking through moderator displacement. A Restricted Insert Component List is used by the licensee to identify BPRA's which should not be reinserted for additional burnup. The twice burned BPRA's in question had not been added to the Restricted Insert Component List because they had not been discharged from Unit 1 Cycle 6 when the Cycle 7 design was initiate They were therefore scheduled to remain during Cycle 7 in the same assemblies in which they were already locate The problem was identified in the internal review process before the four assemblies with twice-burned BPRA's were loaded into the cor The final core loading plan was reissued using alternate BPRA To prevent recurrence, the BPRAs will be added to the Restricted Component list at the time that they are loaded into a second cycl . ._- . _ . . - - _ . , - _ _ _ _ _ _ . ___ _._____ _____ _ _

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The . licensee . deemed -.the deviation nonreportable under- 10 CFR 21 becaus'e : the potential binding problem would not compromise plant-safetys or safety functions'. A third burn on. a BPRA assembly i not fa - core 1 reactivity . concern.-. The inspector concurred with this assessmen b . -- Deviation Report 87-525 Deviation Report 87-525, dated May 16. 1987, documented that BPRA 4P9 had been. loaded.into Unit 1 fuel assembly H33, 180 degrees'out of its'-

intended orientation. The BPRA had originally been in Unit 2, which is ' the - reverse of Unit 1. - To correct the ' problem, the BPRA was pulled from _ assembly H33 and' rotated 180' degrees. _ The orientations of all. other BPRAs were'then verified -to. be correct' .

The licensee concluded'that the incident was non' reportable under 10 CFR.21..'The inspector concurred that rotation of the BPRA would not affect plant safety or safety system function Within thislarea, no problems were identifie .

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