IR 05000416/1985042

Insp Rept 50-416/85-42 on 851102-07.No Violations or Deviations Noted.Major Areas Inspected:Witnessing Integrated Leak Rate Test Reviewing Surveillance Test Procedures & Followup of Outstanding Items

ML20151N945
Person / Time
Site:	Grand Gulf
Issue date:	12/23/1985
From:	Jape F, Macdonald J, Whitener H NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20151N938	List: IR 05000416/1985042 ML20151N935
References
50-416-85-42, IEB-80-24, NUDOCS 8601030246
Download: ML20151N945 (14)

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tp Of og UNITED STATES Do NUCLEAR REGULATORY COMMISSION

[\- n REGloN 11

, g j 101 MARIETTA STREET. * ~t ATLANTA, GEORGI A 30323

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Report No.: 50-416/85-42 Licensee: Mississippi Power and Light Company l Jackson, MS 39205 Docket No.: 50-416 License No.: NPF-29 Facility Name: Grand Gulf Inspection Conducted: November 2-7, 1985 Inspectors:.H.'f.'Wh'itsner muV - .[ 47 -23 -/-[

Date Signed JW MacdonaTd~//nwW. s

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Accompanying Personnel: Christina Petrac , Phillipine AEC (PAEC)

Approved by: # w */ f .M /.3-r278P F.Mape, Section Thief ' Date Signed Engineering Branch [

Division of Reactor 'iafety . ,

SUMMARY

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Scope: This routine, announced inspection entailed 80 inspector-hours on site in the areas of witnessing the integrated leak rate test, reviewing surveillance test procedures, and following up outstanding item Results: No violations or deviations were identified.

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REPORT DETAILS Persons Contacted Licensee Employees

• J. Cross, General Manager

• R. Rogers, Technical Assistant to General Manager

• C. R. Hutchinson, Manager Plant Maintenance

• A. J. Malone, ISI Coordinator

• J. H. Mueller, Mechanical Superintendent

• J. D. Bailey, Compliance Coordinator Other Organizations-Bechtel Leak Rate Test Consultants H. Hill, Engineer B. Patel, Engineer L. Young, Engineer NRC Resident Inspectors

• R.- Butcher

• J. Caldwell

• Attended exit interview Exit Interview The inspection scope and findings were summarized on November 7, 1985, with those persons indicated in paragraph 1 above. The inspector described the areas inspected and discussed in detail the inspection finding No dissenting comments were received from the license The inspectors classified the containment integrated leak rate test (CILRT)

as a failed test in accordance with paragraphs III.A.I.(a) and III.A.6 of Appendix J to 10 CFR 50. This is the first CILRT failure at Grand Gulf and requires the licensee to submit the proposed Type A test schedule for NRC review (paragraph 5.b.(3).(a).

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The licensee was advised that a number of outstanding items were reviewed and closed out during this inspectio These items are summarized in paragraph The inspectors also informed the licensee of the NRC's position regarding the summation of' Type B and Type C leakage as delineated in paragraphs III.B.3 and III.C.3 of Appendix J to 10 CFR 50 and the termination of a Type A test as delineated in paragraph III.A.I.(a) of Appendix J to 10 CFR 5 These positions are delineated in paragraph 6 of this repor s

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The inspectors advised the licensee that two potential violations were identified during this inspection. The apparent issues which involved administrative controls and operations areas were referred to the Resident Inspectors for followu These issues related to: Changing a Technical Section Instruction (09-S-08-2) which in effect changed the boundary of a local leak rate test (penetration 61) in a manner inconsistent with requirements for procedure changes specified in Administrative Procedure 01-S-02- Verification of a valve as locked closed when the valve stem threads and significant leakage during the Type A test indicated that the valve may not be fully close The licensee is still investigating this matte The Resident Inspectors agreed to followup on the above item The licensee did not identify as proprietary any of the materials provided to or reviewed by the inspectors during this inspectio . Licensee Action on Previous Enforcement Matters (Clo:ed) Violation 416/83-46-01 concerned an inadequate local leak rate test procedure, 06-ME-1M61-V-0001, Revision 3, in that specific valve alignments were not identified and uncontrolled documents were used to aid in setting up the valve alignment Upon identification of the violation the licensee issued a temporary pro:edure change (TCN) dated August 31, 1983, to ensure that valve alignments were documented and reviewed until the procedure could be revised. Subsequently, the requirements for identifying and documenting complete valve alignments prior to performing a local leak rate test were incorporated into the test procedure. This procedure is further supported by an approved set of valve alignments and penetration drawings issued in Technical Section Instruction, Local Leak Rate Test Valve Alignment, 09-S-08-2 dated November 2, 1983. The instruction receives the same review and approval that the test procedure receives. The inspectors concluded that the current procedure 06-ME-1M61-V-0001, Revision 26 in conjunction with Technical Instruction 09-S-08-2 provides adequate identification and documentation of valve alignment Violation 416/83-46-01 is close (Closed) Unresolved Item 416/83-46-02 concerned the acceptability of the--

local leak rate test results in that valve alignments were not clearly specified in the test procedur In response to this concern the licensee reviewed all available plant records to verify that test alignments were correct. In that these records were incomplete, some assumptions were made in reconstruction of valve alignment The NRC requested that the licensee categorize the types of assumptions, deductions and logic used in reconstruction of the valve alignments and submit these to the Plant Safety Review Committee (PSRC) for

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review and acceptance (IE Report 50-416/83-46). Based on review of the PSRC minutes of October 26, 28 and November 2, 1983; plant memorandum supporting the PSRC review; evaluations which included PMI 83/12,604, PMI 83/12,138, PMI 83/10,191 and PMI 84/2011; response to violation 416/83-46-01 which delineated the conclusions of the PSRC; review of test results for certain valves which were retested; and discussions with plant personnel involved in evaluation of the local leak rate test results, the inspector concluded that the licensee demonstrated, with reasonable assurance, that the leak rate tests were properly performed or were identified for retesting. Unresolved Item 416/83-46-02 is close (Closed) Unresolved item 416/83-46-03 concerned anomalies identified in the leak rate program during the program re-evaluations as follows: Test frequency for local leak rate testing of electrical penetrations was specified as three years based on the assumption of a continuous monitoring syste The licensee determined that the nitrogen pressurization system in use did not qualify as a continuous monitoring system. Consequently, the electrical penetrations were retested in September 1983, and again in January 198 The test frequency is now specified as two years to conform to Appendix J of 10 CFR 50. The inspectors confirmed that the retest was performed and had no further questions on this matte The test of the safety-related check valve in the air supply line to the airlock door seal accumulators was not clearly defined in the test precedur The licensee determined that the safety-related check valves in the air supply line to the air lock door seal accumulators were not properly vented during the test. Consequently, a temporary procedure change was made and proper tests performed on the accumulator check valves in September 198 The inspector confirmed that the current test procedure, 06-ME-1M23-R-0001, Revision 26, contains the steps for properly venting the check valve and had no further questions on this matter, In some local leak rate tests the test pressure was applied in the direction opposite of the accident pressure during the leak rate measuremen In the extensive review to verify valve alignments and test methods used in the local leak rate test program, the licensee identified a number of valves which had been tested in the reverse direction. The inspector determined that the split wedge gate valves were retested in the accident direction. Other valves tested in the reverse direction were the test connection valves, 3/4 inch or less in diamete Information from the vendor and calculation of forces involved indicates that normal closing of these valves will produce a thrust of

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about 3,333 pounds as opposed to a lif t force of about 3.5 pounds

generated by accident pressure. The inspector had no further questions

at this time.

, Verification of test connection valve position was not clearly stated in the local leak rate test procedure.

i i As a result of the NRC concern that the last step in the leak rate test

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procedure specified that the test connection valve be opened to vent the test volume, the licensee immediately inspected a sample of the

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test connection valves and verified that they had been reclosed. The

[ local leak rate test procedure, 06-ME-1M61-V-001 now requires double verification that test connections are closed and pipe caps replace The inspector had no further questions on this matte Unresolved Item 416/83-46-03 is close . Unresolved Item Unresolved items were not identified during the inspection.

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. Containment Integrated Leak Rate Test (61719)

The inspectors reviewed and witnessed test activities to determine that the primary containment integrated leak rate test was performed in accordance with the requirements of Appendix J to 10 CFR 50, ANSI 45.4, FSAR, the test

, procedure 06-ME-1M10-0-0002, " Containment Integrated Leak Rate Test", the

recommendations specified in ANSI /ANS 56.8, 1981, and the requirements of BN-TOP-1, Revision 1 for a short duration tes Selected sampling of the licensee's activities which were inspected included

(1) review of the test procedure to verify that the procedure was i properly approved and conformed to the regulatory requirements listed above; (2) observation of test performance to determine that test prerequisites '

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were completed, special equipment was installed, instrumentation was calibrated, and appropriate data were recorded; and (3) preliminary evalua-tion of leakage rate test results to verify that leak rate limits were me Pertinent aspects of the test are discussed in the following paragraphs.

, General Observations The inspector witnessed portions of test preparation, containment-- -

pressurization, tenperature stabilization and data processing during

the period of November 2-7, 198 The following items were verifie .

(1) The test was conducted in accordance with an approved procedure

! maintained at the test control center. Procedure changes and test 1 discrepancies were properly documented in the procedur (2) celected test prerequisites were reviewed and found to be complete t

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(3) Selected plant systems required to maintain test control were reviewed and found to be operationa (4) Special test instrumentation was reviewed and found to be installed and calibrate (5) Problems encountered during the test were described in the test event lo (6) Temperature, pressure, dew point, and flow data were recorded at 15 minute intervals. Data were assembled and retained for final evaluation and analysis by the licensee. A final ILRT report will be submitted to the Office of Nuclear Reactor Regulatio No deviations or violations were identified in the above revie b. Containment Integrated Leak Rate Test (CILRT) Performance (1) Method The containment leak rate was determined by the mass point analysis and linear regression technique on a minimum of eight-hours of mass data recorded at 15-minute interval The test was performed at a nominal containment pressure of 1 psig (full accident pressure). A supplemental test was performed for this test conditio In addition, the licensee analyzed the test data in accordance with the requirements and acceptance criteria of BN-TOP-1, Revision 1, to qualify the eight and one-half hour tes (2) Test Description The containment was initially pressurized to 11.5 psig on November 3, 198 The test sequence was as follows:

Date Time Comment November 3 0600 Started pressurization of primary containmen Secured pressurization of primary containment at 12.25 psi Temperature stabiliza-tion bega Temperature stabilization achieved. Leak rate appears to be excessive, approximately _ __ _ - , _ _ .

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6 wt % per da Leakage was

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61 and the main steam valves in lines C and Penetration 61 isolated but the effect is not sufficient to meet the acceptance limit Attempts to quantify the leakage indicated 30 to 50 scfh leakag November 4 0100 Attempts to quantify leakage through the main steam valver indicated about 30 scfh through C line and about 230 scfh through D line. These leakage paths were isolated by closing the vent valves and downstream manual steamline valve Reactor vessel level raised from 65 inches te 84 inche to Reconfirmed temperature 0545 stabilizatio Time zero for CILR Conclude CILRT (8.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />).

1430 to Set up imposed leak rate at 1530 9.4 scfm. One hour stabiliza-tion complete Supplemental test initiate Supplemental test conclude (3) Test Results (a) Type A Test The integrated leak rate test was categorized as a failed test in that a leak rate in the range of to 0.8 weight percent per day (wt %/ day) was measured initially. Leak survey teams identified significant leakages through penetration 61 and the main steam isolation valves in lines C and After isolation of these leakage paths, estimated

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to be greater than 300 scfh, an 8.5 hour5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> Type A test was performed with data samples taken Ot 15 minute interval Analysis of the test data yielded the following test results:

Mass Total Acceptance Point Time Limit Lam (wt.?o per day) 0.137 0.129 0.328 95?; UCL (wt.L per day) 0.141 0.183 0.328

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The results of the different analysis techniques l were reasonably consistent and indicate a leakage of about 30% of La. Calculations performed by the inspectors agreed with the above values. Since the total time analysis of the 95% upper confidence limit (UCL) was less than the test limit of 0.75 La (0.328 wt. ?;/ day), the short duration test was allowe The inspectors concluded that with the leakage from penetrations 61, 7, and 8 isolated, the containment leakage was within the acceptable limi In attachment I of the test procedure the licensee identified the penetrations to be locally tested as follows:

Penetration Function Comment 40 Test Pressurization In use 82 Test Pressurization In use- - - -

61 Standby Liquid Control Vent valve isolated 7 Main Steamline C Leak path isolated 8 Main Steamline D Leak path isolated

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The as-left leakage from these penetrations will be added to the Type A test 95% UCL to determine the final containment leak rat (b) Supplemental Test Appendix J requires that a supplemental test be performed to verify the accuracy of the Type A test and the ability of the ILRT instrumentation to measure a change in leak rate. A known leak rate (Lo) is imposed on the containment and the measured composite leak rate (Lc) must equal, within 0.25 La, the sum of the measured leak rate (Lam) plus the known leak rate (Lo).

The acceptance criteria is expressed as:

Lo + Lam - 0.25 La s Lc s Lo + Lam + 0.25 La Results of the supplemental test show that the composite leak rate Lc was within limits as follows:

0.465% s 0.543% s 0.684%

The inspectors calculation based on a single reading of the flow meter rather than the averaged values differed slightly from the above numbers but supports the same conclusio The inspector enncluded that the supplemental test verified the ability of measuring the containment leakage and was acceptabl . Issues Related To Leak Rate Tests During the inspection the licensee asked for clarification of certain Appendix J requirements. The inspectors identified the NRC position on the following Appendix J requirements: Termination of the Type A Test Section III.A.I.(a) of Appendix J requires that if during a Type A test, potentially excessive leakage paths are identified which will interfere with satisfactory completion of the test or which will result in the Type A test not meeting the acceptance criteria III.A.4.(b) or III.A.5.(b), the Type A test shall be terminated and the leakage through such paths shall be measured using local leakage testing methods. Repairs and adjustments to equipment shall be made and a Type A test shall be performed. As stated, this requirement can have a major impact on the licensee's schedule since, in general, local leak

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rate measurements and repairs cannot be accomplished with the contain-ment pressurize In the Inspection and Enforcement Manual under 10 CFR 50.54 the NRC has i specified testing techniques which meet the intent of the above requirements but significantly reduce the impact of this requirement on the licensee's test schedule. The NRC's position is as follows:

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If during the performance of a Type A test, including the supplemental test, excessive leakage paths are identified which result in the Type A  !

test not meeting the acceptance criteria the leakage path may be I

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isolated and the Type A test continued until completion provided that:

(1) The Type A test as performed after isolation of leakage paths i meets the acceptance criteria of Appendix (2) The leakage paths which are isolated have a design which will

, permit local leak testing of all potential leakage paths subse-quent to the Type A test,

! (3) Local leakage rates ara measured before and af ter repair and i reported to the Commission, i (4) The sum of post repair local leakage and the Type A test 95*ii UCL meet the Appendix J allowable leakage rate, St.mmation Of Type B and Type C Leakage Sections III.B.3 and III.C.3 of Appendix J require that the combined

leakage rate of all penetrations and valves subject to Type B and C

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tests shall be less than 0.6 La. Tne NRC has determined that summation of the maximum pathway leakages for all leak paths meets the intent of the above requirement and satifies the single active failure criterion used in leak rate analysis. Maximum pathway leakage is the largest i leakage measured for any leakage barrier in a leakage path which 4 contains multiple leakage barrier Intent of a Procedure In the discussion of local leak rate testing the question was raised as j to what constitutes a change to the intent of the procedure. At the

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exit interview, the inspector stated that historically the NRC has -

j considered that the intent of a local leak rate test procedure is to define an acceptable way to measure leakage through an isolation barrier. This would include identification of the valve under test, the test method, the test medium, the test pressure and the test boundaries. A change in any of these items is considered to change the intent of the procedure.

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r Drywell Bypass Leakage Rate Test (61719)

i The inspector reviewed the drywell bypass leakage test procedure, Surveil-i lance Procedure 06-ME-1M10-R-0003, Revision 20, for compliance to Technical Specification 4.6.2.2 and to independently verify the results of the drywell

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l leakage rate test performed on June 16, 198 <

The test criteria required that the drywell be pressurized to 3.0 psid,

) allowed to stabilize for one hour after test pressure had been attained and l l that the test would run for four hours following stabilization. One drywell '

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doorlock remained open during the test (the doors should be alternated such

that each door is tested every other test).

The following data were recorded every half hour from stabilization to test

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completion.

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' Drywell Atmospheric Conditions

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a) average dry bulb temperature ( F)

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b) absolute pressure (psia) Makeup Air a) makeup air flow (cu. ft.)

b) make up air temperature ( F)

. c) make up air pressure (psig) Outside Atmospheric Conditions a) dry bulb temperature (*F)

b) dewpoint temperature ( F)

c) Barometric pressure (in. Hg)

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a) suppression pool temperature ( F)

i b) reactor vessel temperature ( F)

c) suppression pool level (ft)

d) reactor vessel level (ft)

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e) Condensate storage Tank Level (ft)

The acceptance criteria states that the drywell bypass leakage' rate shall be- - -

less than or' equal to 3500 SCFM. The actual bypass Leakage rate calculated by the licensee and independently verified by the inspector was 2599.17 SCFM. The June 16, 1984 drywell bypass leakage rate test complied with the L Technical Specification limit and was declared a satisfactory tes The

] successful completion of this test eliminates the test frequency penalty

which would be imposed if'two successive tests failed.

! In the area inspected, no violations or deviations were identifie ! i

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8. Previously Identified Inspector Followup Items (IFI)

(Cinsed) 50-416/83-11-01, Failure of the Drywell Suppression Pool Bypass Leakage Tes The March 10-13, 1983 drywell bypass leakage test was considered a f ailed test. The drywell test pressure could not be achieved as a result of two open electrical conduits. The conduits were temporarily sealed and test pressure was subsequently achieved. The test was declared a failed test because drywell test pressure could not be achieved without modification to the drywell boundary 1.e. , sealing the electrical conduit The licensee did not agree that the test had failed; stating that the two electrical conduits were open as a result of construction activities and were spares which would eventually be permanently sealed prior to nuclear heatup. The licensee also stated that the leakage through the open conduits did not indicate degradation of the drywell integrity as the leakage was a result of construction activities and not the result of degration of the conduit sealing compound NRR concurs with the Region II position that the test should be considered as a failed test. The purpose of the drywell bypass test is to assure that potential steam releases into the drywell will not circumvent the contain-ment suppression pool function by escaping through other leakage path In reference to the Grand Gulf test, the failure to pressurize the drywell identified a major leak path regardless of whether that path was created due to administrative error or due to equipment failure. The subsecuent test frequency will be as required by Technical Specification 4.6. IFI 416/83-11-01 is close . Review of Bulletins, Circulars, and Notices IE Bulletin No. 80-24, Prevention of Damage Due To Water Leakage Inside Containment On October 17, 1980, at the Indian Point Unit 2 (IP-2) facility, a combination of conditions existed such that without the operators'

knowledge, over 100,000 gallons of water flooded the reactor vessel pit and wetted the lower nine feet of the reactor vessel while the vessel was at operating temperature. IE Bulletin No. 80-24, dated November 2, 1980, addressed the conditions which led to the IP-2 event and required action to be taken by the licensee to preclude another similar event from occurring. The licensee was required to submit a written report, signed under oath or affirmation, in response to each item of IEB 80-2 Mississippi Power and Light Company (MP&L), with assistance from Bechtel Power Corporation (report file number 0262/L-401.0/L-403.0, dated January 23, 1981) and Plant Staff (report file number 0290/L-860.0/L-403.0, dated June 16, 1981) submitted the completed review of IEB 80-24 to the Commi ssion. The report (file number:

0260/L-401.0, dated March 31, 1982) individually addressed each item of IEB 80-24 and proyided the MP&L response to each item with respect to GGN _ _ _____ _._._ __ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _

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j IE Circular 81-14, Main Steam Isolation Valves Failure To close

Main steam isolation valve closure failures are primarily related to i the following two _causes: (1) poor quality control air to the pilot valves and (2) binding of the MSIV valve stems with the valve stem

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packing (Refer to paragraph 9c, IEN 80-16). Recommended action for

', holders of construction permits, such as Grand Gulf, was to evaluate

MSIV control air system design and to consider design changes where i appropriate to ensure high reliability and to minimize or eliminate the f 3 common mode failure potential present in current designs. In Grand l Gulf Nuclear Station (GGNS) memo dated March 24, 1982, with file number

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j 0290/8190/J802.4/M-051.0/7500, Mechanical, NPE, recommended the installation of qualified dewpoint monitoring equipment with annuncia-

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tion at all main Instrument Air System branch headers and at the inlet

to the MSIV valve control system Plant staff evaluated the recom-

! mendations of NPE to install qualified dewpoint monitoring equipment and concluded, in GGNS memo file number 0290/0294/8190 dated June 21, 1982, that present design features of the Instrument Air System are 4 sufficient for reliably controlling instrument air quality; therefore, no further action on this item was necessary. Based on Plant Staff's

consideration and decision not to implement the NPE recommendations the i manager of Safety and Licensing closed the files on IE Circular 81-14 memo file number 0290/L-860.0/L-402.0 dated August 26, 198 l i

IE Information Notice 80-16, Shaft Seal Packing Causes Binding In Main i Steam Swing Disc Check And Isolation Valves ,

The inspectors reviewed an MP&L letter dated August 18, 1981, docu-i menting evaluation by plant staff of IEN 80-16 regarding the binding of f

! swing check valves at Indian Point 2 and at Trojan Nuclear Plan In

! both cases, excessively tight shaft packing restricted movement of the t

, valve disc in the main steam isolation valve MP&L's evaluation :

i concluded that a similar condition would not occur at Grand Gulf i Nuclear Station because valve packing is done in accordance with the '

I appropriate vendor manuals. The manuals specifically caution against t i excessively tight valve packing and give preliminary tests to insure i j proper valve operation. In addition, IEN 80-16 has been added to the l

, required reading list for mechanical maintenance personne [

1 Review of outstanding Items

! The following Table summarizes the status of outstanding items reviewed- l during this inspection:

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Violation (416/83-46-01) Closed i j Unresolved Item (416/83-46-02) Closed

Urresolved Item (416/83-46-03) Closed i

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IE Bulletin 80-24 Closed IE Circular 81-14 Closed

IE Notice 80-16 Closed

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Inspector Followup (416/83-11-01) Closed

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