IR 05000255/1986005

Insp Rept 50-255/86-05 on 860119-0313.Violation Noted: Failure to Perform Type a Test as Required by Tech Specs

ML20205M317
Person / Time
Site:	Palisades
Issue date:	04/11/1986
From:	Hare S, Phillips M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20205M307	List: IR 05000255/1986005 ML20205M303 ML20205M312
References
50-255-86-05, 50-255-86-5, NUDOCS 8604150174
Download: ML20205M317 (11)

Text

• o U.S. NUCLEAR REGULATORY COMMISSION l

REGION III

Report No. 50-255/86005(DRS)

Docket No. 50-255 License No. DPR-20 Licensee: Censumers Power Company 212 West Michigan Avenue Jackson, MI 49201 Facility Narre: Palisades Nuclear Generating Plant Inspection At: Covert, MI Inspection Conducted: January 19 through March 13, 1986 N lO c

Inspector: S. M. Hare M //- B6 Date Approved By: M. P. hillips, Chief I l Operational Programs Seccion Date l Inspection Summary l Inspection on January _19 through March 13,19 ~

Areas Inspected:~~~RoutiEe~,~~aincunced' inspecti_8650-255/86005(iiF

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(R_eport No.on byofDRS

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a regiF containment integrated leak rate test (CILRT) activities; CILRT results review; local leak rate test results; and as found CILRT results. NRC l inspection modules completed during this inspection period were 70307, 70313, 70323 and 6172 Results: Of the four areas inspected, no violations were identified in three areas. In the remaining area one violation was identified - failure to perform an as found Type A test as required by Technical Specifications -

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B604150174 860411 PDR ADOCK 05000255 G PDR

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DETAILS 1. Persons Contacted Consumers Power _ Company

1. J. F. Firlit, Plant Manager

1. • D. J. Fitzgibbon, Licensing Engineer

• V. I. Beilfuss, Project Engineer

+#*T. J. Palmisano, Plant Projec's Superintendent

1. • R. A. Fenech, Technical Engineer

• R. E. McCaleb, Quality Assurance Director

• D. Desnoyer, Staff Engineer

+*R. Ward, Nuclear Operations Analyst

+*G. L. Boyers, ISI Supervisor

• D. G. Malone, Senior Engineer s

• J. G. Lewis, Technical Director

• J. D. Alderink, Mechanical Engineering and Maintenance Superintendent

1. K. W. Berry, Director, Nuclear Licensing US NRC

• J. K. Heller, Resident Inspector, D.C. Cook

• D. L. Williams, Regional Inspector

1. E. R. Swanson, Senior Resident Inspector, Palisades

1. C. D. Anderson, Resident Inspector, Palisades

1. W. G. Guldemond, Chief, Reactor Projects Branch 2

1. C. W. Hehl, Chief, Operations Branch

1. A. B. Davis, Deputy Regional Administrator

1. W. H. Schultz, Enforcement Coordinator

• Denotes those attending the preliminary exit interview on February 6, 198 + Denotes those attending the exit teleconference on February 20, 198 # Denotes those attending the Region III enforcement conference / exit interview on March 13, 198 . I L_R_T) Wi t n e s s i n g Co n ta i n me n t I n t e g ra tpe d_ _L e a k Ra_t_e__Te s t_j_C_I Procedure Review The inspector reviewed Procedure No. RT-36 Revision 12, entitled Containment Integrated Leak Rate Test for technical adequacy and conformance with regulatory requirements. With the exception of an open item discussed in Paragraph 2.e. the procedure appeared adequate, Summary of Appendix J Requirements To ensure the licensee's understanding of Appendix J requirements, the inspector had numerous discussions with licensee personnel

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during the course of the inspection. The following is a sumary of the issues discussed with the licensee:

(1) Whenever penetration configurations during a CILRT deviate from the ideal, the results of LLRTs for such penetrations must be

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added as a penalty to the CILRT results at the 95% confidence

level. An acceptable penetration leakage penalty is determined using the " minimum pathway leakage" methodology. This methodolo-gy is-defined as the minimum leakage value that can be quantified through a penetration leakage path (e.g., the smallest leakage of two valves in series). The minimum pathway methodology as

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it applies to Palisades is discussed in paragraph 5. This assumes no single active failure of redundant leakage barrier Additionally, an increase in containment sump or pressurizer level during the course of the CILRT must be taken as a penalty to the CILRT results. If penalties exist, they must be added (substraction is ne,er permitted) to the upper confidence level of the CILRT results.

(2) The Type A test length must be 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or longer to use the mass point method of data reduction. If tests of less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> are planned, the Bechtel Topical Report, BN-TOP-1, must be

, followed in its entirety, including the trending of sensors, except for any section which conflicts with Appendix J or Technical Specification requirements. For either methodology, the acceptance criterion is that the measured leakage at the 95%

upper confidence limit must be less than 75% of the maximum allowable leak rate for the pressure at which the test was performe ;

(3) For the supplemental test, the size of the superimposed leak rate must be between 0.75 and 1.25 times the maximum allowable

leak rate La or Lt. The supplemental test must be of sufficient duration to demonstrate the accuracy of the test. The NRC looks for the results to stabilize within the acceptance criteria, not just bcirg within the acceptance criteri Whenever the BN-TOP-1 methodology.is being used, the length of the supplemental test cannot be less than approximately one

! half the length of the CILRT and the BN-TOP-1 method of data

reduction must be use <

(4) An acceptable method for determining if the sum of Type B and C

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tests exceeds the 0.60 La Appendix J limit is to utilize the

" maximum pathway leakage" method. This methodology is defined

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as the maximum leakage value that can be quantified through a j penetration leakage path (e.g., the larger, not total, leakage

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of two valves in series). This assumes a single active failure i of the better of two leakage barriers in series when perfonning Type B or C test (5) Future periodic Type A, B, and C tests must include both as found and as left results. In order to perform repairs prior to a Type A test, an exemption from Appendix J requirements -

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should be obtained from NRR. The exemption should state how the licensee plans to determine the as found condition of the containment since local leak rate repairs are being performed prior to the CILRT. An acceptable method is to commit to add any improvements in leakage rates which are the result of repairs of adjustments (ras) using the " minimum pathway leakage" methodolog (6) During a CILRT, it may become necessary to reject or delete specific sensors or data points due to drifting or erroneous sensors or data outliers. Data rejection criteria should be developed and used so that the licensee would have a consistent, technical basis for data rejection. One example of an acceptable method for data outliers is descr.ibed in an appendix to ANSI /ANS 56.8 - 1981. Sensor data rejection criteria should be plant specific and based upon the trend of a sensor relative to the average scatter, slope, and/or absolute output of the senso ,

c. Instrumentation The inspector reviewed the instrument calibration data associated with performing the CILRT. A multipoint calibration of all instrumentation was performed. Correction values were generated based on the difference between measurements of resistance from a NBS verified resistance box and actual resistance. All corrections were placed as an array or equation into the CILRT compute The following instrumentation was used in the CILRT:

Type Quantity RTDs 22 Mass Flowmeter 2 Pressure Gauges 2 Dewcells 9 The inspector noted to the licensee that their present data acquisition system while adequate by all existing standards, was lacking in sensitivity (partly due to the low allowable leak rate) to obtain an accurate measure of containment leakage in a 24-hour test, as demonstrated by the Type A test results from this outag Improvement could be realized by either raising the test pressure J to perform a full pressure test (this would increase the allowable ,

leakagerate)orbyobtainingamoreaccuratedataacquisition i syste d. Valve Lineup Verificat_i_o_n Valve lineups for the following systems were verified correct so as to ensure that no fluid could enter the containment atmosphere and so'that proper venting could be provided or penalties taken:

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System Penetration (s)

Primary Coolant System Sample 40 Containment Building Air Sample 28 Nitrogen to Quench Tank 26 Controlled bleed off from RCP's 44 Demineralized Water to Quench Tank 42 Containnnnt Sump Drain to Sump Tank 52, 52A Letdown to Purification Ion Exchanger 36 Air Supply to Air Room 68 Service Air 10 e. Test Witnessing ,

The licensee began' presst.rization on January 21, 1986. After the containment was pressurized to the reduced Type A test pressure P ,

the licensee began the stabilization period. After a stabilizatibn period of approximately 5.75 hours8.680556e-4 days <br />0.0208 hours <br />1.240079e-4 weeks <br />2.85375e-5 months <br />, the measured leakage phase was begun on January 22, 1]S6. Approximately three hours into the test, the licensee noted that the 'first 1.75 hours8.680556e-4 days <br />0.0208 hours <br />1.240079e-4 weeks <br />2.85375e-5 months <br /> of data indicated that they had not stabilized and that they had declared stabilization too early. This resulted in the licensee discarding the first 1.75 hours8.680556e-4 days <br />0.0208 hours <br />1.240079e-4 weeks <br />2.85375e-5 months <br /> of data and reinitializing.the measured leakage phase of the test. The inspector reviewed the licensee's determination and found it to be acceptable. Another 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> into the test, an apparent step change in the lea k ge was encountered. The inspector requested that the licensee provide an explanation for this sudden change in leak rate (from 0.0493 wt%/ day to 0.00179 wt%/ day). The licensee was unable to supply the inspector with a plausible explanatio The inspector reviewed previous Type A test reports to determine if this sudden change in leak rate was attributable to the containment design / characteristics. The inspector noted almost identical characteristics with the Type A test that had been performed in November, 1981. In the report submitted to the NRC dated March 23, 1982, docun:enting the ILRT, the licensee stated that the containment structure had not stabilized until 15-1/2 hours after pressurization was complet The problems with changes in leak rate 25.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> after pressurization during this ILRT coupled with the problems encountered with containment stabilization in 1981 indicate the licensee is declaring containnent stabilization much too early. The insp..ctor stated that the licensee must develop stabilization criteria for their containment that will ensure the containment atmosphere is stabilized prior to them beginning the measured leakage phase of the ILRT. As a minimum the stabilization time period must be increased to reflect the problems encountered with stabilization during the 1981 and 1986 ILRTS. This is considered an Open Item (255/86005-01(DRS)).

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i The measured leakage phase of the test was concluded with 29.75 .

hours of data and an acceptable leak rate. Data prior to th .75-hour point where the leakage step change occurred was included in the calculations, as this data caused the overall leakage to increase (conservative).

After the successful completion of the measured leakage phase, a known leak was imposed and the supplemental portion of the Type A test begun. Approximately four hours into the verification test, the inspector indicated to the licensee that it sounded as if a leak was emanating from the data acquisition panel. The licensee personnel assured the inspector that this was not the case. After the inspector left the general area, the licensee identified a leak in the flowmeter inlet connection which caused the "known leak" to be unquantifiable. As a result, the licensee repaired the leak and eliminated the first five hours of test data, and reinitialized the supplemental test. The licensee lost data acquisition ability approximately four hours later, due to problems encountered with their computer disk drive. Following the repair of the disk drive, the licensee successfully completed the supplemental test with a full ten hours of data.

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No violations or deviations were identifie . Test Results CILRT Data Evaluation The 29.75 hour8.680556e-4 days <br />0.0208 hours <br />1.240079e-4 weeks <br />2.85375e-5 months <br /> CILRT was performed with data being collected and reduced by the licensee every 15 minutes. The inspector independently monitored and evaluated leak rate _ data using the ANSI 56.8 (mass point) methodology to verify the licensee's calculations of the leak rate. There was excellent agreement between the results of the inspector and licensee as indicated by the following summary (units measured in weight percent per day):

Measurement Licensee Inspector Leakage rate calculated 0.0157 0.0157 (Ltm) during CILR Ltm at upper 95% confidence 0.0187 0.0187 leve Ltm at upper 95% confidence 0.02061 0.02061 level including penalties (see paragraph 3.c).

Appendix J Acceptance Criterion at 95% confidence level = 0.75 Lt =

0.75 (0.0713) = 0.0535. As indicated above, the adjusted Ltm at the 95% confidence level was less than the Appendix J Acceptance Criterio :

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. . Suppl _epental Teg Data Evaluation After satisfactory completion of the 29.75 hour8.680556e-4 days <br />0.0208 hours <br />1.240079e-4 weeks <br />2.85375e-5 months <br /> test, a known leakage of 0.073 weight percent per day was induced. The inspector independently monitored the evaluated leak rate data to verify the licensee's calculation of the supplemental leak rate. There was excellent agreement Letween the leak rate calculations of the inspector and the licensee's calculations as indicated in the following summary (units are in weight percent per day):

Measurement Licensee Inspector Calculated leakage (Lc) rate 0.0719 0.0719 during supplemental test Appendix J Acceptance Criterion: Lo+ Lam-0.25La<Lc<,Lo+ Lam +0.25La (0.0709<Lc40.1065). As indicated above, the supplemental test results satisfied the requirements of 10 CFR Part 50, Appendix CILRT Valve Lineup Penalties Due to valve configurations which deviated from the ideal penetration valve lineup requirements for the CILRT, the following penalties must be added using the minimum pathway leakage method:

Leakage Penalty C_ompone_nt_ Description JWeightPercent/ Day)

Pressurizer Level Increase 0.0012 Fenetration 36 -5 5X10 Penetration 42 0.00012 Penetration 44 -0-Penetration 52 0.00054 0.00191 No violations or deviations were identifie . Local Leak Rate Test Resul_t_s__Rev_i_ew The inspector reviewed the local (Type B and C) leak rate test results for this outage and previous outages for acceptability and conformance to regulatory requirements. The inspector noted that the licensee's local leak rate test (LLRT) results for this outage were far in excess of the 0.6 La Technical Specification and Appendix J limit for the sum of penetration and isolation valve leakages. Additional review revealed that previous refueling outages also had excessive LLRT results. This violation of the 0.6 La limit for penetration and isolation valve leakage

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and the continuing failure of isolation valves may be indicative of inadequate corrective action taken by the license As stated in the March 13 enforcement conference (details in IE Inspection Report No. 86008), and coninitted to in a letter dated March 14, 1986 from Kenneth W. Berry to James G. Keppler, the licensee will study the problem with local leak rate test failures. This study and the subsequent corrective action plan should be completed by June 30, 1986. In order to resolve the inspector's ccncerns relative to the licensee's past and planned corrective action for failing containment isolation valves, the licensee is requested to submit this study and planned corrective action for Region III review. Review of this information, relative to the adequacy of past and planned corrective action, will be tracked as an unresolved item (255/86005-02(DRS)).

One penetration which failed its local leak rate-test by a large margin was penetration 40, part of the post-accident sampling syste During his review, the inspector noted the leak test on this penetration was of a 10-second duration and had not been repeated to confirm this measured leak rate. The test lasted only 10 seconds because the licensee was using the pressure drop method of calculating leak rate .and they could only maintain penetration pressure within the test band for that tim The inspector inquired as to why the licensee perfomed only one test since the results of the test were quite subject to error because of its short duration. The licensee's response was that they had made a mistake and that they should have performed additional tests to further ensure the accuracy of the original leak test. The inspector noted that the licensee should revise the local leak rate test procedure to ensure that in similar circumstances (e.g., test duration less than procedural allowable) the local leak test will be repeated until a sufficient level of confidence in the measured leakage is realized. This will be tracked as an open item (255/86005-03(DRS)) pending review of the revised LLRT procedur No violations or deviations were identifie . As Found Condition _of CILRT Results The "as found" condition of the containment is the condition at the beginning of an outage prior to any repairs or adjustments (ras) to the containment boundar Palisades containment testing Technical Specifications Surveillance Requirement 4.6.1.(a).2 and 3 state, in part, that subsequent leak rate tests (after preoperational) shall be perfonned at a test pressure of about 28 psig. The tests shall be performed without any leak detection surveys or leak repairs immediately prior to or during the test, except as noted below. Major leak repairs, if necessary to permit the integrated leak rate test, shall be preceded by local leakage measurements. The local leakage differences, as a result of repair, shall be corrected to P, and added to the final integrated leak rate test result to determine tne subsequent retest schedul .

Further,10 CFR 50, Appendix J, Paragraph III.A.1 requires that during the period between the initiation of the containment inspection and the performance of the Type A test, no repairs or adjustments shall be made so that the containment can be tested in as close to the "as is" condition as practical. ANSI N45.4-1972, Paragraph 4.2 requires "For retesting, an initial record proof test shall be conducted at time periods and pressures established by the responsible organization, before any preparatory repairs are made. This will disclose the normal state of repair of the containment structure and a record of the results shall be retained." The NRC's position on the " initial record proof test" requirement is that it may be waived provided the Type A test results are back corrected for all ras to the containment boundary made prior to the performance of the Type A tes If ras are made to the containment boundary prior to the Type A test, local leak rate tests must be performed to determine the leakage rates before and after the ras. The as found Type A test result.s can then be obtained by adding the difference between the affected path leakages before and after ras to the overall Type A test results. The as found leakage rate results are required and carry the same reporting requirements as the other Type A and Supplemental test results. The correct methodology for back correcting the Type A test results, as described later in this section and in Section 2.b(5) of this report, is the minimum pathway methodolog Contrary to these requirements for an as found Type A test, the licensee has been performing containment isolation valve leak testing and isolation valve repair prior to all of their periodic Type A tests without determining the as found condition of the containment structure. Failure by the licensee to realize the requirements for an as found Type A test resulted in the licensee not realizing they had failed both the 1978 and 1981 Type A test in the as found condition. This is considered a Violation (255/86005-04(DRS)).

To ensure the licensee's understanding of how to calculate an as-found penalty, the inspector and a member of the licensee's staff went over in detail the methods to determine an as-found penalty. The following is a o summary of what was discussed: In the case where individual leak rates are assigned to two valves in series, the penetration through leakage would simply be the smaller of the two valves' leak rate I In the case where a leak rate is obtained by pressurizing between two isolation valves and the individual valve's leakage is not quantified, the as-found penetration through leakage would be 50 percent of the measured leakage and the as-left penetration through leakage would be zero. (This assumes one or both of the repaired valves leaks zero.) In the case where a leak rate is obtained by pressurizing between two isolation valves and only one valve is repaired, the as-found

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penetration through leakage would conservatively be the final measured leak rate and the as-left penetration through leakage would be zero. (This assumes the repaired valve leaks zero.)

The inspector reviewed the quantified as found and as left local leak

" rate test results to determine an as found penalty to apply to this outage's Type A test results. The following is a summary of the as found containment leak rate for this outage (units are in weight percent per day):

Measurement Penalties incurred due to quantified 0.05488 repairs or adjustments prior to the CILRT As found Type A test result 0.07549 Appendix J acceptance criteria for the as found condition of the containment = 0.75 Lt = 0.0535 wt%/ da As indicated above the as found condition exceeded that allowed by-10 CFR 50, Appendix J. This excessive as found condition was largely due to leakage through a Reactor Coolant Sample line (Penetration 40) and the uncertainties involved in its local leak rate test. As denoted above, the CILRT perforced in 1981 also exceeded the as found Appendix J limit. As

two consecutive as found conditions have failed to meet the acceptance

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criteria in 10 CFR 50, Appendix J, and as required by Section III.A.6.(b)

of 10 CFR 50 Appendix J, the next Type A test shall be performed at the

next plant shutdown for refueling unless exempted by the NR ,

No additional violations or deviations were identified.

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6. Open Items Open itens are matters which have been discussed with the licensee, which

! will be reviewed further by the inspector, and which involve some action on the part of the NRC or licensee or both. Open items disclosed during

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this inspection are discussed in Paragraphs 2.e and 4.

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7. Unresolved Items

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Unresolved items are matters about which more information is required in order to ascertain whether they are acceptable items, open items,

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deviations, or violations. An unresolved item disclosed during the

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inspection is discussed in Paragraph 4.

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! 8.- Exit Interview

. The inspector met with licensee representatives (denoted in Paragraph 1)

. on February 6 and February 20, 1986, and at the conclusion of the inspection on March 13, 1986, in Region III and sumarized the scope and findings of the inspection activities. The licensee acknowledged the -

inspector's statements. The inspector discussed the likely informational content of the inspection report with regard to documents reviewed by the

inspector during the inspection. The licensee did not identify any such documents as proprietary.

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