IR 05000410/1986053

Insp Rept 50-410/86-53 on 860922-26.No Violations Noted. Major Areas Inspected:Util Activities Re MSIV Reported Problems & Background History,Including Procurement of New ball-type MSIVs

ML20207J452
Person / Time
Site:	Nine Mile Point
Issue date:	12/11/1986
From:	Gregg H, Strosnider J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20207J440	List: IR 05000410/1986053 ML20207J438
References
50-410-86-53, NUDOCS 8701080460
Download: ML20207J452 (15)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION I

Report N /86-53 Docket N License No. CPPR-112 Priority --

Category B Licensee: Niagara Mohawk Power Corporation 300 Erie Boulevard West Syracuse, New York 13202 Facility Name: Nine Mile Point Nuclear Power Station, Unit 2 Inspection At: Scriba, New York Inspection Conducted: September 22-26, 1986

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Inspector L c

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/ / 86, H.I.Gregg,LippReactorEngineer 'dat6 Approved by: e /lM/d6

. R. Strosnider, Chief, Material & Processes date Section, Engineering Branch, DRS Inspection Summary: Inspection on September 22-26, 1986 (Report N /86-53)

Areas Inspected: A routine unannounced inspection of licensee's activities related to Main Steam Isolation Valve (MSIV) reported problems was conducte The inspection reviewed the background history including procurement of these new ball type MSIVs, procurement requirements, performance and qualification, QA/QC involvement, and problem areas; made independent observations of damaged valves, their failure mechanism, and assessed the licensee's proposed corrective action Results: No violations were identified, however, the licensee program at the time of this inspection's exit had not fully resolved the problems and the test verification was not sufficient to conclude that the MSIVs can acceptably perform their function for all operating conditions. Subsequent to the conclusion of the inspection, the licensee met with NRC and agreed to license conditions to assist in resolving the concern h$$hfj

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DETAILS 1.0 Persons Contacted 1.1 Niagara Mohawk Power Corporation (NMPC)

• C. Beckham, Operations QA Manager

• M. Boyle, Lead NC&V Tec *G. Blackburn, Startup Manager

• L. Fenton, Audit Group Lead

• R. Hammelmann, Lead Mechanical Engineer

• Hansen, Manager Nuclear QA Operations E. Klein, Manager Project Engineering

• A. Kovac, Q1P Manager

• Neild, Assistant to Station Superintendent

• A. Pinter, Site Licensing Engineer M. Ray, Manager, Special Projects

, *C. D. Terry, Manager, Nuclear Engineering & Licensing

• P. Wilde, QA Audit Group Lead

• Yaeger, Manager, Project Engineering 1.2 Stone & Webster Engineering Corporation (SWEC)

• T. Arrington, Resident Manager FQC M. Fachada, Lead Power Engineer R. Huggon, QA Engineer

• D. Koehl, Lead Advisory Engineer SU & Test S. Leonard, Project Engineer J. Panchison, Principal Mech. Engr.

! G. Rodgers, Principal Materials Engineer

• M. Sheldon, Manager Admin. Services

• R. Simons, Supt. Special Projects Group

• C. L. Terry, Project QA Manager 1.3 Crosby Valve Company M. Jackson, Service Representative 1.4 New York State Electric and Gas

• P. Mac Ewan, Site Representative 1.5 Public Service Commission

• P. Eddy, Site Representative

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3 U.S. Nuclear Regulatory Commission

• W. Schmidt, Resident Inspector

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• Denotes those present at exit meeting 2.0 Purpose and Scope of MSIV Inspection This inspection was conducted because of recently reported problems with the 24" ball type MSIVs. The scope of the inspection was to obtain

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information concerning the background history, prior testing, operational experience, operational problems presently being encountered, problem causes, and proposed fixes and to assess the adequacy of the corrective measure For reference, sketches of the valve body assembly and original valve

operator design are presented in Figures 1 and 2, at the end of this repor .0 Background During the inspection entrance meeting, of September 23, 1986 Mr. C. Terry, who has NMPC oversight responsibility for the MSIV's presented the following background informatio Because of leakage and maintenance problems with the Nine Mile Point Unit I and other MSIVs, the licensee wanted to utilize a valve with a vertical stem arrangement. Early in the plant design stage, this was discussed with GE, the NSSS vendor, and SWEC, the architect engineer. At this time EB Valve Co., the original designers of the valves currently installed at Nine Mile Point Unit 2 (NMP-2), presented its new ball valve design concept to NMP In 1977, NMPC made the decision to use the ball valve design because of its anticipated minimized seat leakage, which

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eliminated the need for a costly leakage collection system, and other

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valve features.

, After the decision to use the ball valve MSIVs, the EB Valve Co. changed hands several times, first to Gulf and Western Co. and then in 1984, to Crosby Co.

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In 1979, Gulf and Western issued a comprehensive topical report which described the ball valve generic design and the prototype testing of an 8" valve, and an 8" valve actuator. According to Mr. Terry, the topical

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report was reviewed and the valve was accepted by NRR with two exceptions; the first being the valves would have to meet the 6SCFH leak test require-

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ment and the second that space be available for the possible addition of a

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leakage collection syste The manufacture and shipment of the valves preceded the manufacture and

shipment of the valve actuators. Therefore no testing of the total assembly (valve and actuator) was performed at the vendors site for the 24" MSIVs.

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Soon after installation of the valves (without actuators), a problem of internal corrosion was identified in similar valves at a Swiss plant. As a result of this finding, the MSIVs at NMP-2 were disassembled and the valve body seat spool bores were in-situ rough machined, Inconel cladded and remachined. The valves were reassembled without actuators upon completion of this repai The chronology of valve leak and stroke testing at NMP-2 was described as follows: Initial leak testing, utilizing between seat leakage testing, was done in April 1985 and in March 1986 and results were excellent (each valve had less than 1.2 SCFH leakage during the March 1986 testing).

Prior to this leak testing, during the vendor's 24" actuator qualifica-tion, an overloaded actuator latching roller was identified which resulted in the need for actuator alignment pad adjustment, actuator mounting bracket pinning and a new roller for NMP-2 valves. The required work was completed at the plant sit During initial preoperational closing time testing, problems of slow and varied closing time, sticking of the unlatching mechanism after inactive time periods, a cracked latching roller, and hydraulic cylinder scoring were encountered. Due to these problems the reliability of the actuator was in question and the licensee requested an exemption to enable fuel load with the actuators not operable. During a meeting with NRR to discuss the exemption, questions were raised concerning leak testing between the seats versus through the valve. Based on prior leak testing results NMPC was confident that the MSIVs would meet the 6SFCH maximum leakage requirement with either test method but also wanted to prove the between the seat testing concept. NMPC agreed to reperform leak testing to prove the validity of the between the seat test. However, the between the seat retest results showed that every valve exceeded the 6SCFH Technical Specification leakage acceptance criteria (leakage varied from 17 to 42 SCFH). This was the first indication of a problem with the valve internals. As discussed in Section 7.2, a large number of valve cycles occurred between this leak testing and the previous leak testin It was decided to disassemble one valve for inspection and to determine the cause of the high leakage. Once apart, it was clear that scoring of the seating surfaces on the valve had occurred. Starting at locations on the upper and lower sections of the ball above the port, removal of the tungsten carbide and galling through the weld underlay had occurred. All other valves have been taken apart and have shown varying degrees of the same galling and scoring.

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Because of the leakage and galling on the valves, a meeting was held between NMPC and, the vendor. The outcome was to test two fixes. First, a new ball and new seats were installed in the outboard isolation valve in the 'D' steam line (valve 70), the spring forces at the right and left side of the seat were modified to provide a more favorable load distri-bution. (The spring force on the right side when viewing the port, was

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increased and on the left side was reduced.) Second, Crosby blended out the areas of galling on a damaged ball, and the ball was reinstalled in the inboard 'D' steam line valve (valve 60). When the valves were reassembled stroking was conducted followed by periodic leak checks. The outboard valve was stroked initially 5 times, then seat leak checked, stroking was then conducted in 10 cycle increments followed by leak testing until a total of 75 strokes was completed. All leak checks on the outboard 70 valve, with the new ball and seats and revised seat springs, were satisfactory. The inboard valve 60 was cycled 5 times and failed the between seat leak test. After 15 and then 25 cycles the 6D valve leakage became progressively worse (after 25 cycles leakage was 132 SCFH) and the testing on the valve was terminated. During the 6D and 70 valve tests, through seat leakage was also performed and the results showed that the between seat testing was more conservative and more responsive to the detection of defect NMPC has organized a group to coordinate the MSIV work as a three phase progra The group is (1) looking for a near term fix to the actuator and leakage problems (2) pursuing a long term new prototype development, and (3) looking at contingencies, such as installation of Y pattern globe valves and use of a leakage control syste NMPC has indicated that finding the root cause of the leakage problem as well as coming up with a reliable actuator are the most pressing matter NMPC is developing a schedule for implementing fixes intended to ensure valve operability through the first plant cycle. (As of the completion of this inspection, NMPC planned to ask for an exemption to allow fuel load prior to completion of all MSIV repairs.) NMPC is also trying to get a 24" entire prototype valve assembled so that testing can be done to develop a long term fix which presumably would be implemented no later than the end of the plant's first outag .0 Review of Site Records Subsequent to the entrance meeting discussion, the inspector reviewed various site records; including the purchase order, receipt inspection, procurement specification, topical valve report, vendor selection and qualification, onsite and vendor testing oversight, and QA/QC involvemen Discussions were also held with cognizant onsite personnel regarding these areas. Determinations made by the inspector are as follow The topical report, G&W-FSD 2538, described the valve design and its generic features. Prototype testing was performed on an 8" valve assembly and there was also discussion of 4" valve testing. The 24" valve size was based on analytical extension of the 8" valve and there was no prototype testing of a 24" valve assembly. In addition to the 8" valve with-actuator testing, there was separate 8" actuator testing (not attached to Valve).

An early NRC response, dated October 21, 1982, to the topical report stated that the topical report review does not imply that G&W MSIVs are qualified as there is more to qualification than the analytical approac NRRs review of the report was from a seismic view point onl However, a

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January 2, 1981 letter from Robert L. Tedesco, NRC, to Gerald K. Rhode, NMPC, stated that the use of the valves was not contingent on NRC review of the topical report. The letter stated NMPC could use the new valve design based on their determination that the valves satisfy applicable NRC criteria. The basis given for this position was that the integrity of the valves would be ascertained by strict ir.spection and testing. The letter stated that if the valves exceeded leakage specifications or if later review of the Topical Report by NRC disclosed problems, the valves would have to be repaired, modified, or rer, laced. It also stated that accomo-dations should be made for the possible backfitting of a leakage control syste Valve Qualification was left as a licensee responsibilit Subsequent correspondence from G&W did not further address this issue. From the purchase order, procurement specification, and receiving inspection reviews it was determined that the initial order was placed with Gulf &

Western Co. on July 29, 1977. Change #40, dated February 13, 1984, to the original purchase order reflected the takeover of the valve by Crosby Valve (Division of Geosource, Inc.). It was also determined that the valves without actuators were received in 1981, and installed in 198 The actuators came on site in 1983 and were installed prior to the Type

"C" leak testing of March 1986. The valve receiving documentation included hydrostatic shell, seat, and stem leakage tests, and pneumatic seat leakage tests. Functional performance cycle tests were not performe The procurement specification NMP2-P303D, was reviewed for performance, qualification and testing requirements. The performance requirements provided for sealing on both sides of the ball when in the closed post-tion, the capability of closing the valve within 3-5 seconds, and the ability to operate during and subsequent to a design basis accident. The general technical requirements included cladding of the seat rings with Stellite or an approved alternate material and minimum thicknesses were specified. The qualification aspects of the specification required a static analysis of the valve assembly. Dynamic analysis and dynamic testing of the actuator were require The procurement specification required a hydrostatic shell test and seat testing (2cc/hr/in nominal valve diameter) of each valve. There was a performance testing requirement to cycle the valve and actuator 5 times to verify opening and closing times, however, there was a caveat that if the valve and actuator were shipped separately (as was the case), cyclirg would be done at the job site. One valve was to be tested at operating temperature and pressure. The inspector could not confirm that this testing had been done. The specification also required pneumatic seat leakage testing with the test medium and leakage requirements specified (1/10 SCF /hr/in nominal seat diameter at 45 psig air or nitrogen). The inspector was provided records of the hydrostatic and seat leakage test . - _ _ _ _ - .

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5.0 QA/QC Interfacing Activities The inspector reviewed the QA/QC interfacing activities of both SWEC and NMP-2 regarding the MSIV In each of the SWEC documents reviewed (shipping records, receipt records, QA & QC survey of the vendor, N&D for rework of the valve bodies and their cladding, in-storage maintenance, installation records including Field Planners and Control Reports /E&DCRs/

Weld Data Reports) QA/QC oversight was evident. The NMP-2 QA/QC activi-ties relating to MSIV start-up tests (surveillance reports - on the pre-requisites and performance of preoperational testing, work requests, circuit verification, valve reassembly and QA checks of the preoperational testing) also were reviewed and QA cversight was eviden The present MSIV problems, testing, programs and solutions are critical issues with the licensee and there is QA oversight (both SWEC & NMP-2) on this issu .0 Valve Materials The inspector reviewed the topical report and valve drawing E24-900-15, Rev. K, to determine the valve materials. Additionally, the approximate hardness of the ball coatings was obtained from the SWEC Materials Engineer. The body is forged carbon steel, the ball is cast 316 stainless steel with integral trunions, the seat spool is cast 316 stainless steel, and the seat springs are Hastelloy. The spherical ball surface has a soft Haynes 25 weld overlay (Rb 85), and on top of the weld overlay there is a 0.002"-0.010" surface spray Tungsten Carbide coating (Rc 73). The seat spool seating surface is a weld overlay of Stellite 6 (Rc 37).

Based on the inspectors observations of worn parts, the tungsten carbide coating is more readily scraped off and more readily damaged than the Stellite The extremely hard tungsten carbide also tends to sharpen the stellite 6 seat ID edge at the high load locations, however, the stellite seat was relatively free of any deep scrape marks. The possibility of seat wear at the high loed locations was not checke The observed galled 304 stainless steel thrust washer that mates with the bottom of the 316 stainless steel ball and the 304 stainless steel bearing retainer indicates improper thrust washer material selec-tio It was also an indication that the 24" valve ball is not held in vertical position by the seat spring load .0 Testing and Field Experience 7.1 Prior Test History and Field Experience Based on review of documentation, discussions with site p;rsonnel, and discussions with NRC personnel, testing of the 24" size NMP2 ball valve with their actuators attached was not performed at the vendors

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i site. The only field experience with this size valve was limited to '

a Swiss plant (Liebstadt). The inspector only was able to obtain verbal information regarding use of the valve at Liebstadt as follows. The valve was not an isolation boundary valve (it was a third valve in series to be used for system repair work),

problems were encountered with the valve and it is in the blocked open positio .2 Cycling and Testing and Valves at NMP-2 Based on discussions with NMP-2 personnel the history of valve cycling is as follow From the time of the Inconel cladding repairs completed in January 1985 through the RPV hydro in April 1985 the valves were slow stroked approximately 6 times without the actuators or with two temporary Crosby actuators. During the preliminary type

"C" leak test of April 1985 there may have been an additional 4 slow strokes. For the actual type "C" leak test of March 1986 each valve was tripped closed with its actuator (up to this point the type C leak tests were excellent). During the period between March 1986 and the September 2, 1986 type "C" retest the valves were cycled numerous times during preoperational logic and cycle testing (the number of cycles performed was thought to be in the range 50 to 150 but there was no record maintained). More leak tests were not performed until the September 2, 1986 retest when all valves faile .3 Post Test Examination of Valve Internals at NMP-2 The inspector observed the condition of the damaged MSIV balls, seats, thrust washers and the lapping of refurbished seats to a refurbished ball. The inside of one of the valve bodies was also observed. At the time of this inspection many of the balls and seats were in transit to or from the vendor. At the vendor shop the balls were undergoing the removal of the galled tungsten carbide coating in an area from the port centerline and for 6"-7" to the right of the centerline. This area and other areas where the tungsten carbide coating had come off was being blended smooth. This was to be tested as a possible repair alternative. Toward the end of the inspection,

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a blended ball was tested. During the test the ball was badly gouged l

and scored and this approach was rejecte Observations were made of originally installed parts taken out of valves 7A and 78 for the first time and the refurbished blended ball from valve 6A, that had just returned from vendor. On the original balls, just removed, there was evidence of scraping and removal of large areas of the tungsten carbide coating and scoring of the Haynes 25 by seat ring rubbing action at the top and bottom and on the right

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side of the ball when viewing the port. There were also 1/8" to 3/16" diameter specks removed at different locations around the port edge. There was also a spalled or scraped off diameter area in another location on ball 7B. The 7A valve had similar scrape marks l

but also had some marks at the midpoint of the ball port. The seat l

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rings from valve 78 had faint scratch marks (little depth) but there was a sharp burr on the inner edge of the seat ring that corresponded to the ball damaged locations. The ball damage initiated and was heaviest in areas at the top and bottom where it rubs the sea At these locations the seat arc length is greater in the direction of the ball rotation. This is also the location that takes the highest ball loading and where the seat becomes unstable when a large portion of the seat ring is unsupported as the port eclipses the seat. The seat ring surfaces and the closed position ball surface, however, were relatively free of defect The bottom flat surface of the ball (the surface that bears on the thrust washer) which is 316 stainless steel was badly galled on every ball. The inspector examined the 9\" ID x 18" 00, 304 stainless steel thrust washers and noted that both sides of the washers were badly galled. The inspector observed the body of valve 6A and noted that the stationary bearing retainer plate (a 304 stainless steel plate that covers the radial trunion bearing) was also badly galle The use of 300 series stainless steel for mating bearing parts was ir.:orrect and the licensee was issuing an E&DCR to change the thrust washer to a bronze material. In discussions with licensee and SWEC personnel regarding this problem, they related that the vendor said the spring loaded seat design was intended to support the ball in its position and the ball weight would not be carried by the thrust washer. This design may have worked acceptably in smaller valves of this type but the design was apparently not adequate for the increased weight of the ball in the 24" valve. From information obtained from the assembly crew, the thrust washer also is used to position the ball vertically, relative to the seats, and is then backed off s1 9htl From observations of some of the balls there was evidence of some radial scraping of the upper shaft (not to a high degree) due to l

contact with the lantern ring and packing gland. The ID clearances i of these parts may not have been large enough, however the damage was minimal and did not contribute to the leakage or operability problems.

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7.4 Site Leak Testing of Repair Options During Inspection j

l' Leak testing of the 6D and 70 valves was in process during this inspection. As mentioned in the entrance meeting discussion, valve 7D had new ball and seats from the storeroom and a modified seat spring force arrangement. To provide seat ring stability, the spring load on the right side facing the ball port (the side that doesn't eclipse the port) was increased and the spring load on the left side (the side that doesn't maintain full seat contact as the port is eclipsed) was reduced. This valve was between seat leak tested after 5 cycles and then after each additional 10 cycles until 75 cycles were achieved. Some through seat leakage tests were also performe Test results of valve 70 were always less than 5 SCF . -

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The valve 60 testing which had a repaired ball (the areas where the tungsten carbide scraped off were blended at Crosby) and the original seat spring force resulted in unsatisfactory leakage on the first leakage check. This valve failed between seat leak tests after 5 cycles and became progressively worse (reached 132 SCFH) after 25 cycles when the test was terminated. Valve 6D was then tested with another refurbished ball similar to the last test. The seat spring load was modified identical to the 7D valve that passed the tes This valve was between seat leakage tested and also failed. The result after 5 cycles was 18.1 SCFH and after 25 cycles was >100 SCF The 60 and 7D valves that had just undergone cycle and seat leakage tests were disassembled and observations were made of the internal The 70 ball was in good condition after 75 cycles but had some burnish markings at the ball top and bottom from the seat rubbing at the high leading locations. The seat ring had some slight scuff marks but the seat ID edge was smoot The 6D valve that showed high leakage after 5 cycles and had only undergone 25 cycles of testing had extensive ball damage at the high loading areas. Deep gouges were evident through the blended areas where there was no tungsten carbide coating and extended into the coated area, and in the tungsten carbide coated areas there were large scraped or spalled off sections. The seat ring didn't show extensive damage but there were sharp edges on the seat I.D. in the area corresponding to the ball damage near the open port. There was no extensive damage on the surface of the ball that provides sealing in the closed positio The inspector noted that there was no onsite measurement or seat contact check of the removed seat against the ball when in the closed position.

l 8.0 Proposed Valve Design Modifications

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l The inspector reviewed the licensee's E&DCR to change the thrust washer material from 304 stainless steel to a bronze material because of galling of the 304 stainless steel material. The E&DCR was not fully completed and the licensee advised that this matter would be completed and available for the inspector's reviev at the next inspectio The licensee now intends to utilize the hydraulic system to open and close the valve. The original design used the cylinder to open the valve and latch it in the open position and the hydraulic system had no valve closing functio Due to problems with the latching

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mechanism and high unlatching shock loads of the original design, the licensee / vendor have designed a hydraulic system to be used in opening and closing the valve and the mechanical latching will not be used. Hydraulic pressure will maintain the valve in the open posi-tion and solenoid operated valves (S0V) will exhaust the fluid to

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allow closure. This system will require a new cylinder and new or rebuilt SOVs. The licensee explained that the existing SOVs have had leak problems with metal seating surfaces. Testing of a modification

, with Teflon seats has given better preliminary results but there are potentially enviromental qualification pro,blems due to radiation effects on Teflo The question of the classification of SOVs and the hydraulic cylinder was raised. The licensee does not believe all this equipment to be seismic Category 1, but intends to demonstrate it is capable by testing. The inspector questioned whether the safety function of the S0Vs wouldn't justify a Category 1 classification and environmental qualification. The licensee advised that completed details of qualification would be provided for the inspectors review at the next inspectio .0 Open Items The licensee has submitted three separate MSIV construction deficiency reports:

(0 pen) 86-00-20 MSIV leakage problems, (0 pen) 86-00-19 MSIV closure time problems, and (0 pen) 86-00-18 MSIV roller bearing proble As described in the preceding paragraphs the current testing and repair efforts have not fully resolved the three reported problems. Additional design work is in progres These items will remain open until the licensee's final fixes are made, adequate testing is performed and NRC reviews the completed licensee

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action and verifies the operational adequacy of these new ball valve MSIVs. This report updates these open CDR .0 Summary and Conclusions

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10.1 Summary of Inspection Findings i Based on the observation of parts, review of past problems, current l testing, proposed solutions, review of documentation, and discussions l with cognizant personnel, the following determinations were made during l this inspectio *

The vendor's analytical (without testing) extension of the 24" ball valve design from 8" and smaller valves did not identify the problems encountered upon actual testing of the valve l

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Vendor testing and field experience with the 24" size valve was minima *

The design has problems in seating stability at the high loading location of ball during port eclipsin *

The tungsten carbide coating material on the valve ball scraped off during testing. There was also scoring / galling of the material below the tungsten carbid Stellite 6 seat rings were in generally good condition after testing but did have a slight, sharp burr at the inner edge locations caused by high load contact with the tungsten carbide coating during port eclipsin *

The bottom of the ball, thrust washer and bearing cover plate were

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galled after testing, suggesting the seat springs do not hold the weight of the 24" bal *

Test results of one valve with modified seat spring loads to prevent seat rocking cycled 75 times were good but burnish marks were evident on the ball. All other testing with different combinations of internals failed. Additional tests (not a sampling of one) will be necessary to ensure operabilit The ball from this valve had burnish marks at the high load locations

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The seat from this valve, was free of any deep scratches and free of any sharp edges on the ID edge The thrust washer and bottom of the ball from this valve were galled.

l l A modified hydraulic system to both open and close the valve is in

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Current design fixes in both valve and actuator are not perceived as the final version. The licensee and vendor are involved with l considerable test and rework effort.

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Overall QA/QC involvement was satisfactory.

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10.2 Conclusions Based on the details of this inspection the following conclusions have been reached concerning the acceptability of these new ball type MSIVs. The one successful test with modified seat springing, proposed thrust bearing change, and the modified actuator tests demonstrated positive steps toward resolving existing problems and establishing acceptable valve performance. However, it is anticipated that more design modifications and verification testing are necessar .0 Exit Meeting

. The inspector met with the licensee's representatives (identified in paragraph 1.0) at the conclusion of the inspection on September 26, 1986, to summarize the findings of this inspection. The NRC Resident Inspector, W. Schmidt, was also in attendanc During this inspection, the inspector did not provide any written material to the license .0 Licensee Activities Subsequent to this Inspection Subsequent to this inspection's exit meeting, the licensee met with NRR on the subject of the adequacy of the MSIVs. The licensee committed to, 1) an additional confirmatory LLRT to assure leak tightness capability, and 2) a detailed full scale prototype test to confirm the adequacy of the valve desig The facility operating license NPF-54 issued on October 31, 1986 included a license condition stating that prior to criticality the licensee will provide satisfactory engineering solutions, and preoperational and surveillance testing for the outstanding CDRs related to the MSIVs ( , 86-00-19, and 86-00-20).

The inspector reviewed the licensee's plans and determined that they were l sufficient to permit fuel load and subsequent activities under the Operating License.

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