ML20093D251
| ML20093D251 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 07/06/1984 |
| From: | Fay C WISCONSIN ELECTRIC POWER CO. |
| To: | Harold Denton, John Miller Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20093D254 | List: |
| References | |
| TAC-52665, TAC-52666, NUDOCS 8407160188 | |
| Download: ML20093D251 (7) | |
Text
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l IMSCORSin Electnc eaara couranr 231 W. MICHIGAN, P.O. BOX 2046. MILWAUKEE, WI 53201 July 6, 1984 Mr. H.
R.
Denton, Director Office of Nuclear Reactor Regulation U. S. NUCLEAR REGULATORY COMMISSION Washington, D. C.
20555 Attention:
Mr.
J.
R. Miller, Chief Operating Reactors, Branch 3 Gentlemen:
DOCKET NO. 50-266
SUMMARY
TECHNICAL REPORT OF TYPE "A",
"B",
AND "C" CONTAINMENT LEAK TESTS POINT BEACH NUCLEAR PLANT, UNIT 1 In accordance with Section 15.4.4.I.D of the Point Beach Nuclear Plant Technical Specifications and Section V.B of 10 CFR 50 Appendix J, the attached summary technical reports are submitted on type "B" and "C" leak tests during the Unit 1 refueling and maintenance outages of October, 1981, through December, 1981; October, 1982, through December, 1982; October, 1983, through April, 1984; and on the type "A"
test performed during the October, 1983, refueling and maintenance outage.
The type "A"
test was performed by the Quadrex Corporatien, Tulsa, Oklahoma.
We are currently reviewing, for approval, the detailed final report.
We have enclosed a summary report prepared in accordance with the format specified in ANSI /ANS 56.8-1981.
The complete report, including all procedures, equipment calibrations, test data and results will be retained by Wisconsin Electric and will be available for your review.
A routine, announced NRC. inspection by Messrs.
S. M.
Hare and L. A.
Ryes was conducted during the performance of this type "A"
No items of noncompliance or deviations were identified (inspection report 84-05 dated 04/25/84).
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o Mr. H. R. Denton July 6, 1984 Summary of Data The overall as-found leakage of the type "A" test was 0.1892% by weight per day of the containment atmosphere, or 89.3% of the allowable rate.
This includes the addition of the local tests of those penetrations which were not vented during the conduct of the type "A" test in accordance with Appendix J to 10 CFR 50, Section III.A.1.d.
The leakage contributions to containment from other sources (see attachment for an explanation of these sources) were also added.
The overall as-found leakage of tye type "B" and "C"
tests conducted during the 1981 refueling was 164,542 sec described in Section III.C.3 of per minute or 71.2% of 0.6 La Appendix J to 10 CFR 50.
After repairs, the overall leakage was 7,053 sec per minute or 3.1% of 0.6 La.
LER 81-014/01T provides additional information on this item.
The overall as-found leakage of the type "B" and "C" tests conducted during the 1982 refueling was greater than (not quantifiable) 205,455 sec per minute or 88.9% of the 0.6 La.
After repairs, the overall leakage was 4,276 scc per minute or 1.9% of 0.6 L.
LER 82-020/OlT provides additional information a
on this item.
The overall as-found leakage of the type dB" and "C"
tests conducted during the 1983 refueling was greater than (not quantifiable) 306,080 sec per minute or 132.4% of 0.6 La.
After repairs, the overall leakage was 8,799 scc per minute 1'
or 3.8% of 0.6 L.
LER 83-009/OlT provides additional information a
on this item.
Also enclosed is the type "B" and "C" leakage testing summary for the period between the October, 1981, type "A"
ILRT and the March, 1984, type "A"
ILRT.
This summary includes all of the test data obtained during and between each of the refueling outages.
The summary also contains comments made in regard to all as-found leakage rates which approach or exceed 0.6 La.
Very truly yours, f
lb Vice Presid nt-uclear Power 1
C..W. Fay Enclosures Copy to NRC Resident Inspector
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REACIOR CONTAINMENT BUILDING INTEGRATED _
LEAKAGE RATE TEST FOR POINT BEACH UNIT l_
I
'I.
General Data Owner - Wisconsin Eleectric Power Company A.
B.
Docket Number 266 Location - Two Rivers, Wisconsin C.
Containment Description - 3{ foot pre-stressed post-tensioned concrete D.
cylinder with ! inch welded ASTM A-442 steel liner Date Test Was Completed - April 2,1984 E.
II.
Technical Data Containment Net Free Volume - 1,000,000 cubic feet A.
B.
Design Pressure - 60 psig C.
Design Temperature - 286*F (Pac) - 53 psig Calculated Accident Peak Pressure D.
(Tae) - 286*F Calculated Accident Peak Temperature E.
III. Test Data A.
Test Method - absolute Data Analysis Technique - mass point B.
C.
Test Pressure - 30 psig Maximum Allowable Leak Rate (La) - 0.4% per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> D.
Maximum Allowable Operational Leakage Rate at Pressure P.
E.
(L ) - 0.212% per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> (UCL) -
Calculated Leakage Rate at Upper Confidence Limit F.
0.2001% per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> G.
Measured Leak Rate (Lam) - 0.1845% per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> (required additions to measured leakage rate)
H.
Penalties Isolated Penetrations 0.0004% per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 1.
Primary system leakage to RCDT 0.0027% per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 2.
PORV " backup" nitrogen bottJe leakage 0.0016% per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 3.
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' e I.
Adjusted calculated 95% UCL leakags rate - 0.2048% per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> J.
Adjusted measured leakage rate - 0.1892% per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> IV.
Verification Test A.
Calibrated Leak Superimposed - 0.1473% per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> V.
Analysis and Interpretation The fourth periodic type "A" integrated leakage rate (ILRT) of the Point Beach Nuclear Plant Unit 1 containment was performed during the period between March 30, and April 2, 1984, with satisfactory results. The testing program was conducted in accordance with the requirements of the Point Beach
- FSAR, Chapter 15, " Technical Specifications," Paragraph 4.4 Containment Tests.
The integrated leakage rate test instrumentation system was designed to provide " absolute" method measurement of containment leakage at a high level of accura;y. Twenty one (21) RTD's and 6 dewcells were located within the containment to provide information on the areas of the contained volume. Two (2) pressure sensing lines were provided from the containment to the test panel for containment pressure, and verification flow instrumentation.
The instrument error analysis shows this measurement system to have an accuracy of 10.0276% leakage rate per day at a 95% confidence Ibnit (UCL).
Data analysis and reduction was accomplished through the use of a mini-computer system. Data was obtained from the test panel, on a 15 minute interval, and manually inserted into the mini-computer system. The test procedure and data analysis computer system were provided by the Quadrex Corporation.
Th'e aosolute value of the total measured leakage rate (Lm = 0.1845) was 87% of the allowable operational leakage rate (L
= 0. 212). The calculated leakage rate at a 95% upper confidence lLait was 0.2001% per day.
To verify the results, an " induced leakage rate" slightly less than~ the maximum allowable operational leakage rate, was superimposed on the actual leakage rate at 30 psig. Due to system limitations, the superimposed leakage equaled 75% of the maximum allowable operational leakage rate.
The absolute value of the difference between measured leakage from the type "A" test data and measured leakage from the verification test data was 0.0005 at a 95% upper confidence limit.
1
o
_3 The elapsed tbnes, the least squares leakage rate, the 95% confidence level rate, total time leakage rate, and the total leakage are tabulated below:
Tabulation of Calculated Parameters 4
Test 30 psig CILRT 30 psig verification Time 29.75 hours8.680556e-4 days <br />0.0208 hours <br />1.240079e-4 weeks <br />2.85375e-5 months <br /> 7.75 hours8.680556e-4 days <br />0.0208 hours <br />1.240079e-4 weeks <br />2.85375e-5 months <br /> g = 0.0852%/ day g = 0.1845%/ day L ** = 0.2320%/ day L
Least Squares L Leakage Rate 0.1996%/ day 0.3465%/ day 95% Confidence
= 0.2001%/ day
=
=
Leakage Rate 0.1283%/ day 0.2756%/ day Total Time
= 0.1581%/ day
=
=
Leakage Rate
[
0.0414%
Total Leakage 0.1960%
0.0890%
=
- This column represents leakage rates based upon the leakage measured i
during the verification added to the induced leakage rate of.1473%/ day, j
The duration of the type "A" test phase was affected by an unusual amount of data scatter in the deweell instrumentation, and an apparent perturbation in f
containment atmospheric conditions. At approximately 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> into the type "A" test, an unexplained perturbation occurred giving a measured rise in
[
containment average temperature without a corresponding increase in pressure.
This resulted in a calculated increase in leakage.
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Immediate and subsequent investigations did not reveal the cause for the perturbation.
It is believed that the event is associated with the instrumentation l
system and not a result of an actual containment abncspheric perturbation.
Because of the perturbation, acceptable leakage values were not recovered l
until the 28th test hour.
Fo.. lowing an additional 1-3/4 hours of data, the l
type "A" test was successfully terminated based on Technical Specification requirements.
i i
Prior to the perturbation, the least squares leakage was 0.1016% per day i.
and the 95% UCL leakage value was 0.1562% per day. Reinitializing the data' af ter the perturbation results in leakage values which are consistant with previous tests and more representative of the actual leakage. The reinitialized least squares leakage was 0.0567% per day, and the 95% UCL leakage was 0.0857%
per day. Thus, we believe the reported leakage values are greater than actual.
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VI.
Leakage Value Adjustraents Due to the test configuration of the containment, 11 penetrations were not subjected to the 30 psig type "A" test pressure. These 11 penetrations, justification, and type "C" test results are identified below:
Penetration Justification Type "C" Results CVCS Supply In use to control 14 seem Line (#26) primary system pressure CVCS Letdown In use to control 18 seem Line (#10) primary system pressure RCP "A" Seal.
Maintain flow of clean 8 scem Injection Line (#29A) water through RCP seals RCP "B" Seal Maintain flow of clean 4 seem Injection Line (# 29B) water through RCP seals RCP Seal Return Maintain flow path for 215 seem Line (#11) seal leakage RCDT Drain Line Maintain flow path for 78 seem
(#9) seal leakage Service Air Lir.e Modified to allow for 11 seca
(#33C) containment depressurization (Note 1)
Containmant Pressure Modified to provide a pressure 8 sccm sensing Line (#31A) point for type "A" test purposes (Note 1)
Reactor Makeup Proper venting of line is not 9 sccm Water Line possible without securing entire
(#30C) reactor makeup water header which would affect Unit 2 Auxiliary Charging Proper venting of line is not 10 seem Line (#32C) possible when seal injection lines are in use Post-Accident Portion of PACVS used to provide 3 seem Containment Vent verification flow path (Note 2)
Penetration, Portion of Isolation Arrangement Containing H2Vit Type "C" leakage tests were performed prior to the modifica' tion NOTES:
1.
for the type "A" test to assure a true "as-found" condition.
2.
H2V11 is normally isolated during the type "A" test, and a vent path provided through the test panel. This valve was inadvertently opened during the test and the line was isolated at the panel. Thus it was not properly tested during the type "A" test. The type "C" test was performed following the type "A" test.
During the period between the 5 psig containment inspection and the post-depressurization inspection, the backup nitrogen bottle for PORV 1CV-430 This represents leaked 60.44 scf of nitrogen into the containment atmosphere.
a leakage of 0.0016% per day which should be added to the type "A" test values.
In addition, primary system leakage to the reactor coolant drain tank also added to the containment volume. This source represents a leakage of 0.0027% which should be added to the type "A" test values.
Thus, the adjusted least squares leakage is 0.1892% per day, and the adjusted 95% DCL leakage is 0.2048% per day.
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