ML20236C524
| ML20236C524 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 03/13/1989 |
| From: | Doyle J Citizens Association for Sound Energy |
| To: | |
| Shared Package | |
| ML20236C504 | List: |
| References | |
| NUDOCS 8903220195 | |
| Download: ML20236C524 (19) | |
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.l TECHNICAL EVALUATION OF CPSES.1982 HYDRO TEST ,j
'AND'ASME SECTION XI-VT-2 TEST .
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Prepared for . _
CASE (Citizens Association for' Sound Energy)-
Prepared by:
' CASE' Consultant Jack Doyle q.
i March 13, 1989 'l r
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a INDEX.
1 to _i TECHNICAL EVALUATION OF CPSES 1982 KYDRO TEST l AND ASHE SECTION XI VT-2 TEST- l l
by CASE Consultant Jack Doyle !
. Page 3l Description and purpose of.the-' study 1 P
Phase-1 is the 1982 Hydro" Test 1 Analysis, General 3 Phase 1 Conclusions .10 Phase 2: .the VT-2 test in conjunction with. hot functional test- 11 Concerns 11 i
., The forthcoming VT-2 test 13 l
The VT-2 test'as a proof of adequacy 14 Conclusions 17 a
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TECHNICAL EVALUATION OF CPSES 1982 HYDRO TEST AND'ASME SECTION XI VT-2 TEST s i by' CASE Consultant Jack Doyle This is a study in two hases.
PhaseL1 is the 1982. Hydro Test. The purpose of the study is to determine the' technical. validity of the hydrostatic test which was performed in July.of 1982 in Unit 1 of CPSES. .No attempt is made in this analysis to , 1 e
determine the quality of the documentation or the paper trail associated a
with this test.
Phase 2 is the VT-2 test in conjunction with hot functional test. The purpose of the second part of this study is 'to determine what concerns are associated with the Reactor Coolant System (RCS) as a result of the long period that has elapsed between the 1982 hydro test 'and the current time, l
and what the results of the VT-2 tests will accomplish to reduce or-eliminate such concerns. 3 i
e :
Phase 1 is the 1982 Hydro Test The purpose of the study is to determine the technical validity of the hydrostatic test which was perfo'med r in July ofL1982 in Unit-1 of CPSES. No attempt is made in this analysis to determine the quality of the documentation or the paper trail associated with this test. .In order to=
perform the study, the test must be evaluated on the basis of its primary
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.. . intents. In this regard,'there.are=two principal elements to consider, and
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l- they are as follows:
(1) Was there an acceptable achievement of the test pressure which is based on the.following:. design pressure, 2485 psi; X 1.25 for the absolute-1 9
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k minimum to a maximum of design pressure X 1.25 X 1.06 (code allowable overpressure without analysis).
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This places'the. upper and lower bounds of the test from a lower bound-of 3107 psig to an upper bound'of approximately 3'293 psig. The tolerance of l'.'06 times. design pressure may be fouad'in the ASNE code through the following sequence: At NB-6222,'Haximum Permissible, Test Pressure, "The-stress limit specified.in NB-3226 shall be used in determining the maximum l permissible' test pressure. .In multichambered components pressure-may be l simultaneously applied to the appropriate adjacent chamber toisatisfy the.
stress limits." The referenced' governing' document 4 mentioned in the above citation is as follows: l "NB-3226 Testing Limits.
"The evaluation of pressure test loadings (NCA-2142.3) shall be in accordance with (a) through (e) below, except that these rules do-not apply to the items in NB-3500:
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"(d) For t a 1.25 design pressure hydrostatic test of NB-6221 or 6
I the 1.2 to 2.25 design pressure pneumatic test of NB-6321, the 'l stresses shall be calculated.and compared to the limits of (a), i (b), and (c) above. This calculation and the fatigue evaluation l of (e) below need not be revised unless the actual hydrostatic test pressureuof NB-6221 exceeds the 1.25 design pressure by~more- 1 than 6% or the actual pneumatic test pressure of NB-6321 exceeds i 1.25 times the design pressure. Considered as included in the ,
above is that the hydro test pressure involves a tolerance '
according to the procedures of +30 psi -0 psi ~".
(2) The next element for consideration within this evaluation is the second major step involved in ' the hydro test procedure. This! involves the. I inspection for the integrity of welds, high stress points, etc., at the-prescribed pressures.
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Analysis, General 1 q
In order to proceed with the evaluation, certain factors involved with 1
the test must be determined. Among these factors are pressure attained and the integrity of the RCS system. Relating to the pressure, the following information is available from the documentation of the 1982 hydro test:
(1) At 0456 on July 31, 1982, the pressure reached 3127 psig (this l l
information is available on page 36 of the test log). During the test. -l period from 0457 through 0524 on July 31, 1982, the test pressure varied ;
I between 3130 psig and 3135 psig on the operator's gauge (this information may be obtained from the test data sheet). By my interpolation (for the 1
actual 3135 psig pressure) from Westinghouse predictions due to variations l l
In elevations, based on the 3107 minimum test pressure (see Westinghouse l l
1etter WPT-4566), the maximum pressure at the bottommost point would be 3190 l l
psig. Since the actual test pressures fall within the bounding limits of 3107 minimum to 3293 psig maximum, the intent of the achieving of the test pressure has been accomplished.
(2) The simplest method to address the possibility of the integrity of the second major function of the test is to quote from the reports on the observed conditions at the time of the test. This is the inspection by the NRC, Docket No. 50-445/82-16 dated August 17, 1982, in a letter to Texas Utilities Generating Company, and at that time it was sent to the attention of R. J. Gary, Executive Vice President and General Manager. Attached was an Appendix containing a brief description: Inspection Conducted: July 1--
31, 1982; Inspector: D. L. Kelley, Senior Resident Reactor Inspector; Approved: T. F. Westerman, Chief , Reactor Project Section A.
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7-Starting at 2. (on page 2), Preoperational Test Procedure Review, it states:
"The following preoperational tests were reviewed in draft form:
"lCP-PT-02-04 Independence of Redundant Class IE Trains "lCP-PT-47-02 Refueling Cavity Purification "lCP-PT-49-06 Boron Addition and Control System "This review was made to determine if the following had been addressed:
l "a. Management Review. l "b. Format clearly defines testing to be performed.
1 "c. Test objectives are clearly stated.
"d. Prerequisites are identified.
"e. Special conditions (if any) are specified.
l "f. Acceptance criteria are identified and requirements are ;
i specified for comparison of results with the acceptance i criteria.
"g. Source of acceptance criterion is identified.
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l "h. Initial test conditions are specified. I "1. Reference to appropriate FSAR sections, drawings, specifications, and codes are included. j 8
"j . Step-by-step instructions of sufficient detail are included to ensure that conduct of the test will result in valid conclusions.
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"k. Provisions for documenting that required steps have been performed and space for recording data are included. !
l "1. Temporary circuit changes, installation of jumpers, and l restoration of circuits after testing are properly documented.
"m. Independent verification of critical steps or parameters is addressed.
"No violations or deviations were identified during this review." j 1
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And at 3. Secondary Cold Hydro (pages 3 and 4), it states:
"On July 9, 1982, the applicant performed a Hydrostatic Test of sect. ions secondary plant. These sections included portions of systems that are safety-related. They are:
"a. Main Steem System from the main steam isolation valves (MSIV) to and including the steam generators.
"b. The main feedeater system from the main feed containment isolation valve to and including the steam generators.
"c. Auxiliary feedwater system from the containment isolation valve to the steam generators.
"The NRC inspector conducted a review of the test procedure (CP-CPM 6.9I, Rev. 5, ' Pressure Yosting') to ascertain the testing procedure addressed:
"a. The applicable codes for acceptance criteria.
"b. The test boundary was defined.
"c. The proper valve lineup and checklists were included, =
"d. Also, that the procedure, when performed, would result in viable and accurate data.
"The NRC inspector witnessed the test and has reviewed the test results. The results were:
"a. One leaking steam generator tube was discovered.
"b. Five pin hole leaks were discovered in seal welds at the steam generator tube sheets.
" Note: The leaks were very small and were of the slow dripping type.
"There were no other weld joint leaks identified. The six leaks will be repaired by plugging the steam' generator tubes associated with each of the six leaks. The applicant is also going to do a 100% eddy current test of the tubec in all four steam generators prior to plugging.
"During the conduct of the test, five gagged steam generator safety valves leaked past their seats. These valves will be removed and inspected.
"No violations or deviations were identified."
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At 4, Primary System Hydro (page 4), it states:
"On July 31, 1982, the applicant performed a hydrostatic test on the primary system.
"Prio r to the test, the NRC inspector reviewed the following:
"a. 1CP-PT-55-1, Rev. O, ' Reactor Coolant System Cold Hydrostatic Test'.
"b. System drawings which described the test boundary.
"The test procedure was approved by the Joint Test Group on June 18, 1982, and authorized to be performed on July 22, 1982, by the Lead Startup Engineer. The NRC inspector monitored the performance of the test to verify that:
"a. The test was being performed in accordance with the procedure, "b. Changes to the test were accomplished in accordance with approved procedure, and "c. The performance of the test was controlled and conducted in a way to accomplish valid test resulta.
"On July 30, 1982, the applicant had completed all steps leading to pressurization of the plant to test pressure (3127 psig + 30 psig-opsig). The test pressure was reached in the early morning hours of July 31, 1982. The NRC inspector witnessed pressurization to the 2400 psig point. The NRC inspector also made an inspection of portions of the test boundary between 1000 psig and 1300 psig.
"The test results indicate the test met the acceptance criteria of the test procedure. The only leakage identified was from valve packing and bonnets. A total of 14 gpm was attributed to this source. There was no other identifiable leakage.
"No violations or deviations were iden61fied."
The purpose of including the above was to aid in understanding of my report. I wanted to establish the fact that as of 1982 an effort had been expended to assure that the hydrostatic test was done in a proper manner.
While I neither accept nor reject it, it is an additional instrument of confidence in conjunction with the current commitments of TU Electric as to the adequicy of the welds. The report also reinforces my acceptance of the 6
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test pressure portion of the test (that the pressure achieved was 3127 l psig).
In reference to the leaks referred to by the NRC, the leaks must be put into perspective. These were what are commonly referred to as " weepers."
The total of all of the leaks was less than the FSAR allowable limit of 1 gpm. In reference to the disposition of the leak problem, an NCR equivalent by Westinghouse was issued. The document generated was.FDR-TBXM-#10180 and corrective action, although belatedly, was performed.
The lack of s concerted study for this portion of my report, in relation to this problem, can best be understood if we first determine the impact of the leaks on the test validity.
To properly address this point requires a position to be developed based on the industry and NRC approach to leaking from the primary to the secondary side of the total system. The source of documentation indicating that such leakage is tclerable under the laws and codes is as follows:
As a result of the Atomic Energy Act of 1954 or Title 2 of the Energy Reorganization Act of 1974, principal among the elements that were codified are the general design criteria for nuclear power plants, and in part include as follows:
From the Code of Federal Regulations:
10 CFR Part 50, Appendix A, Criterion 1 "Overall Requirements: 4. Fluid Systems; Criterion 30, Quality of reactor coolant pressure boundary components which are part of the reactor coolant pressure boundary shall be designed, f abricated, erected, and tested to the highest quality standards practical. Means shall be provided for detecting and, to the extent practical, identifying the location of the source of reactor coolant leakage." (Emphases added.)
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The reference to reliance on this GDC may be found in the Final Safety Analysis Report (FSAR) for CPSES. The pertinent reference is as follows:
"5.2.5 Detection of leakage through reactor coolant pressure boundary.
"The leakage detection systems are intended to sense leakage from the reactor coolant auxiliary systems into the containment and to provide the means to locate such leakage.
"The safety significance of leaks through the reactor coolant pressure boundary (RCPB) can vary widely, depending on the source of the leak as well as the leakage rate in duration. Therefore, the detection and monitoring of reactor coolant leakage into the reactor is necessary.
"The leakage detection systems provide information which permits the plant operators to take immediate corrective action should a leak be evaluated as detrimental to the safety of the plant.
"Leahage detection system design objectives are in accordance with the requirements of 10 CFR Part 50, GDC 30, and NRC Regulatory Guide 1.454 Additional descriptions of the leakage detection systems are contained in the Technical Specifications, section 16.2." (Emphasis added.)
The provir. ions of GDC are taken into consideration in the guidance offered by provisions of the ASME code,Section III, 1980 Edition, Subsection NB, at NB-6215 where is states:
"NB-6215 Examination for leakage at the application of pressure.
"Following the application of the hydrostatic test pressure for a minimum of ten (10) minutes (NB-6224), examination for leakage shall be made of all joints and connections and of all regions of high stress such as regions around openings and thickness.
transition sections except in the case of pumps and valves which shall be examined while at test pressure. This examination shall be made at a pressure equal to the greater of the design pressure or three-fourths of the test pressure and shall be witnessed by the inspector. Leakage of temporary ga kets and seals installed for the purpose of conducting the hydrostatic test and which will be replaced later may be permitted unless the leakage exceeds the capacity to maintain system test pressure for the required amount of time. Other leaks such as from permanent seals, seats, and gaske; ed joints in components may be permitted when specifically allowed by the design specifications. Leakage from temporary seals or leakage permitted by the design specification shall be directed away from the surface of the component to avoid masking leaks from other joints." (Emphases added.)
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-y The des'ign parameters for allowable leakaie during operation /1/ are- ,
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' * '- covered in the technical specifications and incorporated-into'the FSARLas- l 1
follows:
q 5.2'5.1.4.
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" Limits for reactor coolant leakage through the RCPB is limited ,to )
the following: -
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"(1) Identified. leakage:"]_2_/ 2
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"(a) I gallon'per minute total primary to secondary leakage-through all' steam generators not isolated from the RCS'and.
500 gallons per day through any one steam generator.not- j
. isolated from the RCS.'
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"(b) 10 gallons per minute total leakage from other sources j other than (a) (items 1, 3, 4, 5, and 6'in section
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5.2.5.1.1). )
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"(2) Unidentified leakage:
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"(a) 1 gallon per minute limit." /_3,/3 (Emphases added.) j i
Since there are FSAR design provisions for~ leakage from'the primary to '
secondary side of the steam generator, the provisions of ASME NB-6215 apply; l
(next-to-the-last sentence) which states:"Other leaks suchfas from permanent --
g seals, seats, and gasketed joints in components may-be permitted when specifically allowed by the design specifications." -(Emphasis added.)
Therefore, as'far as I can determine, there is no irregularity ~ ]
associated with the existence of pinhole leaks to be found in the codes or i regulations. To carry this point one' step further, in reference to the 4 r '
f_l,/ I recognize that TU Electric's position is that.Section 5.2.5.1.4 of 2 the FSAR does'not apply to the cold hydrostatic test; and 1 agree with that position. However, for purposes of my evaluation, the fact'.that some leakage.is. allowed under those FSAR provisions-does provide me with a measure of. additional confidence (to. assume that one gallon per.
cinute during operation?is acceptable,Lbut 20 drops per, minute during a~ i test is not' allowed) when coupled with the enhanced-Section XI VT-2' '
test TU has agreed to perform.
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2 The 500 gallons per day is equivalent to 1/3'of'a gallon per minute.
13] 3 "l', gallon per minute limit" applies to the total system.
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m v e o caveat cited in the code provision (although it does not identify leaks from permans nt seals) which reads as follows: " Leakage of tem'porary gaskets and seals installed for the purpose of conductirg the hydrostatic test and whic'h will be replaced later may be permitted unless the leakage exceeds the I capacity to maintain system test pressure for the required amount of time."
l (Emphasis added.) '
I can find no one who maintains that the pressure was not met and held during the 1982 cold hydrostatic test, and f rom Revision 0,1CP-PT-55-1, j page 32 of 88, the following is found in reference to the pressure test:
"3127 (+30 -0)- psig reached at 0456 7/31/82. t "3127 (+30 -0) psig maintained until 0524 7/31/82."
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Therefore,'the pinhole leaks had no impact on the test pressure. !
Phase 1 Conclusions While 1 can find no problems of a technical nature frem my perspective which could invalidate the July 1982 hydro test of the RCS,1 do have problems with the unique history of the system. Additionally, the
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- acceptability of the 1982 results is also dependent on the status of changes l
made to the RCS, if any, over the course of the years. In other words, if l any new spool pieces have been added, and if they have not been hydroed, this might change my conclusion. But from what I understand, there are only l maybe two or three spool pieces that were changed on the primary side; there were a number changed on the secondary side, but on the primary side (and this is RCS we are discussing), there were only a few installed. In j reference to these spool pieces, it is my understanding that they have been hydroed. In the event that other spool pieces have been changed, I would have to be assured that such sections have been rehydroed to the prevailing l codes and procedures.
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. Phase 2: the VT-2 test in conjunction'with hot functional test 1
- The purpose of the second part of this; study is? to determine what concerns are associated'with the ICS as a result of the.long period that has
. elapsed between the 1982 hydro test' and' the current time, 'and' how the VT-2 tests will' reduce or eliminate such' concerns.
Concerns: .
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-There are concerns involving several areas related to the timeframe
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- outlined above. These are as outlined in the following:
- 1. The probability of localized accelerated corrosion caused by the- I increased electromechanical activity associated with stagnant solvents. This would generally.be manifested at the. weld joints I
due to the anodic characteristics in this-region. 1
- 2. The probability that denting has ' occurred in the steam generator .
tubes in the period between the 1982 hydro test and the present.- !
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- 3. The anknown impact that the lay-up has.had on the" piping systems, j l
or rather the lack of a planned lay-up program.to protect the pipes against corrosion during long periods o'f' inactivity.
- 4. To momentarily stray from the RCS system and venture into the area.
of the secondary side of the plant, there are, in addition to the above primary side concerns, concerns with microbiological intrusion.
- 5. Marine incursions also raise considerable concerns, with particular attention on the corbicula (clam) problem.
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- 6. . There is yet -another concern relating to both the primary ~ and the secondary systems. This involves the fact that there has:been a J l decided lack of a corrosion monitoring program in' the' past six l 1
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years suchlas the' current program which is'now under development.
- 7. Although not;the final concern in this area, algae does offer an i I
. area for thought, especially when considering concentration cell (another form of corrosion) problems. ,)
LI The above list, while not representing the full range of concerns 1 associated with the' current status of the Unit 1-facility at Glen Rose, is indicative of theftypes of concerns to be found.
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Of most interest for this report, it is'to be noted that the principal I
area of attention associated with the above concerns is to:be found when.one- I 1
considers the joints and welds. For this reason, the principal. point of concern involves the current condition of-these welded areas and joints. In' addition, in relation to the valves, the lack of maintenance of the packings adds a secondary concern in this region. 1 l
The potential for problems in these areas would hold true regardless of the status of the 1982 hydro test. It is for the foregoing reason that less than complete attention was devoted to proving or disproving the adequacy of the weld integrity portion of the original hydrostatic test. To reemphasize, the potential for-problems in these areas would hold true l
regardless of the status of the 1982 hydro test. For example, aa I told Mr.
l Christopher Grimes of the NRC during the meeting on the hydrostatic test
-issue, even if the 1982 test could be proven to be absolutely perfect,f1 ,
l l would still have concerns as outlined above.
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- .. r . o, The forthcoming VT-2 test. i I
A test was proposed _by TU Electric in response to the concerns of the NRC, CASE, and the State of Texas (#TXX-89007, letter dated January 11,.
1 1989, from William J..Cahill, Executive Vice President,-TU Electric, to'NRC, Washington, D.C., copy of which is attached). . The test'would be~ performed-to raise confidence levels for the various systems at CPSES. The test
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procedure includes the following parameters:
1 (a) The RCS test, which is to be conduc'ted in conjunction with: the . hot 0 functional test, would be performed at temperatures of a minimum of 500 degrees F.
(b) The RCS system preasure would be in excess .of. 2,200! psig for the .,
3 test.
(c) The inspection of'the RCS would be fully documented?to provide a.
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1 permanent record of the implementation.
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l (d) The parties (NRC, CASE, State of; Texas) would have the opportunity' '
to observe.the procedures-involved in the test (by virtue of the settlement for' CASE, and by law in the case of the NRC and the State of Texas).
The principal concerns as. discussed earlier involve the integrity of the joints, welds, and the valve packing. This is because'there is almost no doubt that the pressure component of the 1982 hydro test was accomplished as desired. There can be no reason offered, therefore, to repeat this- '
element of the test.
Since I feel it is the integrity of the welds, etc., that are of paramount concern, the question surrounding the VT-2 test from'my point:of
' view is: Will the test, as. proposed, achieve the goal of ensuring that the s
welds are adequate and that the valve packing has not deteriorated?
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e *' s The VT-2 test as a proof of adequacy During the original hydro test of 1982, the fluid temperature was slightly over 150 degrees F. and the pressure was about 2485 psig for the l weld integrity portion of the test.
The major difference between the ASME Section III test and the l proposed VT-2 test may be found in a number of factors: j 1
(a) The. basic test pressure is slightly less for the VT-2 procedure l
than was used in the ASME test of 1982, unless the thermal effect ;
l is taken into consideration, in which case the VT-2 test will {
l induce higher strains on the piping systems and by definition the welds. This is in keeping with the code provisions for reduction in pressure requirements with an increase in temperature for VT l l
type tests.
(b) The fluid density for the VT-2 test is less than the cold hydro i'
fluid density.
(c) The temperature of the medium is significantly higher for the VT-2 test than was the case for the 1982 ASME test.
(d) The insulation will not be removed for the VT-2 test.
(e) The VT-2 inspection will be performed after a soak time of four hours has expired.
, It is the differences which introduce the confidence that the VT-2 test l
will satisfy the concerns as relates to the welds and the areas of high failure probability such as the valve packing. From the above list of differences between the tests, only one VT-2 feature is not as intense as was the case of the 1982 ASME test. This involves the fact hat the pressure will be approximately 10% less for the VT-2 test (in absolute 14 E__________
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l terms, thermal' fact' ors notwithstanding). The fact is this will (normally)
-reduce the rate of leakage by a factor about equal to the square root of the
! pressur'e ratios.
Offsetting this negative aspect of the VT-2 test are several positive factors: first, the mediums are not the same, as may be determined from-the l
temperatures during the two tests. In the case of.the ASME test, the medium'"
_ was water (temperature less than 212 degrees F.), but_in the case of the VT-2 test, the medium will, in the presence of a flash path, be gaseous (steam, '{
since the temperature exceeds 212 degrees F.). The advantages and l
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disadvantage of this difference lie in the fact that, while there is less l water content in steam, there is also far less restriction to the movement of steam through similar minute passages in welds'. Another fact is'that the steam will also, in many cases, produce noise. relative _to the parameters of passage (for example: orifice configuration; continuity of: path;.Reynolds number; etc.). Water does not produce noise at these leak rates. This noise introduces a second check on the failure in weld areas'.
The two factors which would normally tend to reduce the quantity of_' j water passage insulation and lower pressure are offset by the four-hour soak time involved in the VT-2 test and the flashing of t'ne low-density high-temperature water to a high-pressure steam jet.
In reference to the soak. interval as the inspection period, consideration must be given to the fact that the fluid does not reach the prescribed temperature and pressure instantaneously. It is a' stepped procedure where the pressure and temperature _'are brought up in' fixed increments over a period of hours. The interim period between,:for example, ,
1500 psi and the 2200 psi test range will be on the order of a minimum'of, l
1 say, an hour. During.this period, any leakage present will be collecting 15 t
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t outside the pressure boundary, although not observed. .Therefore,'there is an' additional time period at ' variable pressures which will also exhibit leakage if leakage paths are available.-
There is another' factor which will' tend to assist leak detection during the VT-2 test and that involves'the high temperature of the medium present. .As the medium passes through the weld portion, the heat will be 1
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- to the lagging which will create a temperature differential in 'j i
areas'of leakage. . To explain the preceding statement, the insulation will exhibit varying degrees of heat; there is no constant temperature when you pass through any' substance (whether it's steel, wood, aluminum, or.
l insulation). The temperature througn the insulation is a variable; the closer to the pipe, the hotter it is. When a 500 or:550d'egree pipe is.
being dealt with, before water could condensate a portion ofLthe insulation (well over half of it) would already have been passed through. At that point, some condensation would start-to'be collected in the fibrous material j I
of the insulation. But in this case, in addition there is a jet which is l driving it, a very high force as the water flashes to' steam. So it will-be I l
forced out to the lagging, which is metal (a very poor insulator); as soon as the heat gets in that area, the metal will pick it up instantly and there will be a temperature differential.
The fact that the insulation is present will, on the surface, make it-more difficult to instantiv pinpoint the location of leaks, but will not render the leak undetectable. .Therefore, while location might be' masked,.
the presence of moisture will be revealed at the low points of the various. !
runs. Further, if a weld passage would allow about one drop per minute in water content (with the drop about the size noted in a leaky faucet) to 16
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penetrate the pipe, thia would be sufficient to penetrate the joints in the lagging during the four-hour test.
As a final point, the method of test used is an enhanced Section XI pracedure. The Section XI procedure has proven adequate in the past for detecting leaks in the various systems of plants throughout the country.
CONCLUSIONS It is evident from the above that the VT-2 test will provide a high level of confidence in the acceptability for the Reactor Coolant System (RCS), at least in relation to the welds and condition of the valves. And this must be considered in light of the fact that a test had been performed l l
in 1982. I could not find argument with the maximum pressure segment of the 1982 hydro test, and at this point am only relying on the NRC's report of l
the 1982 test as a backup inspection in conjunction with the current VT-2 j l
test.
The stctement made above is not without caveats. The acceptability of I the VT-2 test is dependent on the procedures which are established for the test. Beyond this, the execution of the procedures is also of paramount importance for developin5 confidence that the program will render the results which are anticipated.
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