L-96-329, Requests Approval for Authorization of Alternative Refueling RWT Bottom Design
| ML17229A188 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 01/06/1997 |
| From: | Stall J FLORIDA POWER & LIGHT CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| L-96-329, NUDOCS 9701090172 | |
| Download: ML17229A188 (37) | |
Text
CATEGORY 1 REGULAT
. INFORMATION DISTRIBUTION
.STEM (RIDS)
ACCEi~hION NBR:9701090172 DOC.DATE: 97/01/06 NOTARIZED:
NO FACIE> 50'-" 335 St. Lucie Plant, Unit 1, Florida Power
& Light Co.
AUTH.NAME AUTHOR AFFILIATION STALLPJ.A.
Florida Power
& Light Co.
RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)
I DOCKET I 05000335
SUBJECT:
Requests approval for author.izati,on of alternative refueling RWT bottom design.
DISTRIBUTION CODE: R047D COPIES RECEIVED:LTR l
ENCL J SIZE:
TITLE: OR Submittal: Inservice/Testing/Relief from ASME Code GL-89-04 NOTES:
RECIPIENT ID CODE/NAME PD2-3 LA WIENS,L.
COPIES RECIPIENT LTTR ENCL ID CODE/NAME 1
1 PD2-3 PD 1
1 COPIES LTTR ENCL 1
1 E
INTERNAL: ACRS TER RES/DET/EIB EXTERNAL: LITCO ANDERSON
", NRC PDR 1
1 1
1 1
1 1
1 1
1 1
1 AEOD/SPD/RAB NRR/DE/EMEB OGC/HDS3 RES/DET/EMMEB NOAC 1
1 1
1 1
0 1
1 1
1 D
NOTE TO ALL "RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE!
CONTACT THE DOCUMENT CONTROL DESK, ROOM OWFN 5D-5(EXT. 415-2083)
TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!
TOTAL NUMBER OF COPIES REQUIRED:
LTTR 14 ENCL 13
Florida Power 5 Light Company, P.O. Box 128, Fort Pierce, FL 34954-0128 January 6,
1997 L-96-329
'0 CFR 50.4 10 CFR 50.55a U.
S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.
C.
20555 RE:
St. Lucie Unit 1 Docket No. 50-335 Request for Authorization of Alternative Pursuant to 10 CFR 50.55a (a)(3), Florida Power and Light Company (FPL) requests approval of an alternative refueling water tank (RWT) bottom design.
FPL has determined pursuant to 10 CFR 50.55a (a)(3) that the proposed alternative will provide an acceptable level of quality and safety, and that compliance with the specified requirements would result in hardship or unusual difficultywithout a compensating increase 'in the level of quality and safety.
In-service inspection (ISI) Relief Request 13, FPL letter (L 190) dated July 30,
- 1993, requested approval of a temporary non-Code repair for the RWT bottom until the next Unit 1 refueling outage.
The Unit 1
RWT is an ASME Class 2 structure.
Relief Request 13 was approved by NRC letter dated October 21, 1993.
During the Fall 1994 refueling outage it was determined that a Code repair of the RWT bottom was not practical and on November 16,
- 1994, FPL requested approval of an alternative non-Code repair to correct through wall leakage and corrosion of the Unit 1
RWT bottom.
On November 25,
- 1994, NRC approved the addition of a
reinforced vinyl ester liner to the bottom of the RWT until the St.
Lucie Unit 1 steam generator replacement outage.
As part of the
- approval, the NRC requested FPL to complete ongoing laboratory testing and in-situ inspections to confirm the ultimate capabilities of the lining.
FPL has completed the evaluation of the reinforced vinyl ester liner and is requesting approval of the reinforced vinyl,ester liner as a permanent replacement of the RWT bottom.
The enclosed evaluation justifies the reinforced vinyl ester liner's an acceptable alternative to the original bottom design and, with the proposed augmented inspection program, provides a level of quality and safety equivalent to the original design.
97OXoeoa7a 97010~
g <)
PDR ADQCK 05000335 p
\\
I 1
I
St. Lucie Unit 1 Docket No. 50-335 L-96-329 NRC approval is requested by June 2,
- 1997, to support outage planning for the upcoming Unit 1
steam generator replacement
- outage, which is currently scheduled to 'start October 20, 1997.
If the alternative is approved, this letter contains new regulatory commitments to conduct an augmented inspection program of the reinforced vinyl ester RWT bottom liner during the remaining life of the plant.
In summary, the program for the remainder of the second ten-year ISI interval and the third ten-year ISI interval consists of a remote visual examination during refueling outages SL1-15, SL1-16, SL1-18, SL1-19, and SL1-21.
A full hands-on examination would be conducted during refueling outages SL1-17 and SL1-20.
The augmented inspection program for the fourth ten-year ISI interval and subsequent intervals will be submitted as part of the ISI programs for the respective intervals.
In addition, the caulking material between the RWT bottom and the concrete ring wall will be inspected on an annual basis.
Details of the proposed augmented inspection program are provided in Section 8 and Table 1
of the Enclosure.
Please contact us if there are any questions about this submittal.
Very truly yours, J.
A. Stall Vice President St. Lucie Plant JAS/GRM Enclosure cc:
Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, St. Lucie Plant
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 1
ST ~ LUCIE UNIT 1 REFUELING WATER TANK REQUEST FOR ALTERNATIVE TANK BOTTOM DESIGN
- 1. 0 ZQRBRRFa The purpose of this submittal is:
a 0 To demonstrate that the liner material presently installed on the St. Lucie Unit 1 Refueling Water Tank bottom reflects an alternative design which provides acceptable levels of quality and safety which are equivalent to those provided by the original Code of record.
b.
To request approval of the installed liner material as an alternative design to be used on the tank bottom for the remaining duration of the tank life.
C ~
To establish the augmented inspection schedule (and types of inspections) proposed for verification that the RWT liner will continue to perform its required functions.
2 '
The refueling water tank (RWT) is an above ground storage tank which provides a source of primary grade water for refueling, reactor coolant
- makeup, reactivity control during plant operations, and accident conditions (Reference 9.1, Sections 3.1.2.2, 3.1.2.8, and 3.5.4).
The RWT is a Quality Group B, ASME Class 2 structure, and was designed and erected in accordance with ANSI B96.1-1967 (Reference 9.2).
The RWT provides the Technical Specification required minimum volume of 401,800 gallons of borated
- water, which ensures that 371,800 gallons are available for injection for emergency core cooling.
The RWT boron concentration is maintained at a
minimum value of 1720 ppm to ensure an adequate shutdown margin with the reactor in cold shutdown with all Control Element Assemblies withdrawn (Reference 9.1, Section 3.1.2.8, and Reference 9.3, Section 6.3.2.2.1) 3 '
Relief is requested from the Repair and/or Replacement requirements of the ASME Boiler and Pressure Vessel
- Code,Section XI, 1983 Edition through the Summer 1983
- Addenda, Articles IWA/IWC-4000 and IWA/IWC-7000 and IWA/IWB-3000, respectively.
In particular, Florida Power and Light Company
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 2
(FPL) proposes to leave the 'installed fiberglass-reinforced vinyl ester liner in place on the Unit 1 RWT bottom, and to consider this installation as an alternative design equivalent to a Code repair or replacement of the RWT bottom.
In support of this request, FPL proposes an augmented inspection program for the bottom liner installation.
4 ~ 0 4.1 A steady loss of RWT inventory was observed for several weeks in June and July of 1993.
The rate of the loss measured at that time was approximately 2 gpm.
In July,
- 1993, an acoustic emissions (AE) analysis was performed using externally mounted equipment and a transducer mounted on a mini-rover submarine.
From this analysis, a single leak approximately 3/16 inch in diameter was located in an area on the RWT bottom near the east side of the tank.
4.2 A review of Generic Letter No.
90-05 (Reference 9.4) was performed to determine the basis for allowing non-Code repairs to Code class components.
It was determined that any non-Code repair to Class 1 or 2 piping must be performed in accordance with an engineered specification which would provide a
boundary that would be of equal structural strength as the original design basis of the component.
Code Relief Request No.
13 was prepared and submitted to the NRC (Reference 9.5) requesting NRC approval for a non-Code repair involving the use of an epoxy coating to adhere an aluminum plate to the tank bottom.
In the relief
- request, FPL committed to providing a
Code acceptable repair during the Fall 1994 refueling outage.
The
- NRC, in accordance with 10 CFR 50.55a(g)(6)(i),
granted the requested relief and accepted the temporary repair until the Fall 1994 refueling
- outage, at which time the RWT bottom plate was required to be repaired or replaced in accordance with the provisions of the ASME Code (Reference 9.6).
The non-Code repair was implemented using a
1/8 inch thick, 3 inch diameter piece of aluminum plate and Duromar SAR-UW epoxy.
Additional AE testing confirmed that there was no further leakage from the identified location (Reference 9.7).
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 3
4.3 Engineering documents were prepared to support the implementation of a permanent Code repair during the Fall 1994 Unit 1 refueling outage.
This repair, as designed, involved:
a ~
Removal of the section of the bottom plate which contained the identified
- leak, and which had been temporarily repaired in 1993 using aluminum plate and Duromar SAR-UW epoxy.
b.
Addition of a
new 1/4" aluminum filler plate, with bearing material as necessary to provide uniform support for the new plate section.
c.
Sealing of the filler plate to the existing bottom plate by the use of Belzona 1111 epoxy sealant.
d.
Welding of a
new 1/4" aluminum plate section to the existing bottom plate to cover the opening left by the removal of the temporarily repaired plate.
When the bottom plate section was removed from the RWT bottom during the Fall 1994
- outage, visual inspection revealed corrosion on the exterior surface; scattered pitting (hemispherical in shape) and patches of a loosely adherent white corrosion product (likely aluminum oxide) were found.
The depths of the ten deepest pits ranged from 0.065 inches to 0.225 inches, with an average depth of 0.107 inches.
Most of the surface displayed a dark gray color, indicating a passive state prior to removal;
- however, several of the pits were shiny and silver in color, indicating a state of active corrosion prior to removal.
Portions of the surface were free of any evidence of corrosive attack.
The previously repaired hole was seen to have originated from the plate's exterior surface; this was deduced from the sloping profile of the hole.
These findings are documented in the root cause analysis performed by FPL's Component Support and Inspection (CSI)
Group (Reference 9.8).
During the installation of the new plate section, difficulties were experienced in completing the Code repair.
The wall thinning of the base
- material, coupled with conditions associated with welding inside the contaminated environment, led to localized defects.
This resulted in an inability to qualify the welds; for this reason, the Code repair could not be implemented.
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 4
4 '
As an alternative to the Code repair, a fiberglass reinforced vinyl ester liner (Protecto-Line 800 system, manufactured by Dudick, Inc.)
was applied to the inside surface of the RWT bottom.
The liner system is a
1/8" (approximate) thick coating consisting of a prime coat, a troweled base coat with a layer of fiberglass
- roving, and a top coat.
Prior to application, the aluminum surfaces to receive the liner were sandblasted to obtain the specified surface profile.
The surface was inspected to ensure proper preparation for the application of the coating.
The liner was applied over the entire tank bottom, and extended approximately 24 inches up the tank wall.
The liner was visually inspected to verify proper installation.
The installation of this liner system was performed during the Fall 1994 Unit 1 refueling outage in accordance with PC/M 128-194 (Reference 9.9).
Personnel training, surface preparation, liner installation, and visual inspections were performed under the direction of FPL Nuclear Engineering s
Coatings Specialist.
The RWT was placed in service immediately following the installation and inspection of the liner material; the liner system has satisfactorily performed its required functions since its installation.
The liner installation is considered an alternative non-Code repair.
For this reason, FPL submitted Relief Request No.
13A to the NRC for approval of the use of this liner (Reference 9.10).
In a telephone conversation on November 16, 1994, the NRC provided verbal approval for the installation of this liner in the RWT.
By NRC letter (Reference 9.11), which also transmitted a Safety Evaluation Report, the NRC granted relief to install and use the Protecto-Line 800 system, stating that it would provide an acceptable level of quality and safety.
In this letter, the NRC stated that, at the time of the Steam Generator Replacement
Additionally, the NRC stated that FPL has committed to the following:
a
~
b.
c ~
Visual examination of outage.
Continued monitoring leakage.
Completion of ongoing ultimate capabilities the lining during each refueling, of the RWT for indications of laboratory testing to confirm the of the lining.
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 5
5 0
5.1 FPL's CSX Group performed an evaluation of the as-found condition of the 14 inch square section of plate removed from the RWT bottom, and of the soil samples taken from the area beneath the removed plate, in order to determine the failure mechanism of the RWT bottom (Reference 9.8).
The following tests were performed as part of this analysis:
a ~
b.
c ~
Resistivity tests on soil samples Determination of chemicals in soil samples Evaluation of DC potential measurements conducted on the RWT.
The very low chloride, nitrate, and sulfate anion levels, along with the near neutral pH values and high electrical resistivity values found, indicate that the soil beneath the RWT is non-corrosive.
No detectable levels of oil were found in the soil samples.
The tank-to-soil corrosion potentials measured around the tank rim were more positive than documented potentials for aluminum alloys in simulated sea water.
This result indicated that the exterior surfaces of the floor plates were in an active state of corrosion.
The recorded values likely resulted from a
galvanic couple between the floor plates and the copper ground
- grid, which would have rendered the plates susceptible to corrosive attack; this,
- however, would have required a more conductive electrolyte than the specified sand-oil cushion.
Visual inspection of the interface between the tank floor and the concrete ring wall revealed the absence of a joint sealing compound.
The conclusion of the root cause evaluation was that the failure mechanism of the RWT was galvanic corrosion (resulting from a galvanic couple between the exterior surface of the RWT aluminum alloy floor and the surrounding copper ground grid) which was manifested as pitting type attack.
The root cause of the failure was determined to be the absence of a seal between the tank bottom plates and the concrete ring wall, which permitted the periodic ingress of water into the sand/oil cushion layer beneath the tank.
This water likely contained dissolved salts which had been formerly deposited on the tank walls and the surrounding earth.
As this water permeated the sand layer beneath the tank, it rendered the soil more conductive, thus increasing the susceptibility of
0
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 6
the exterior of the tank floor plates to, corrosive galvanic attack.
5.2 The root cause evaluation (Reference 9.8) included a
recommendation for installation of a joint sealing compound between the tank bottom plates and the concrete ring wall to prevent further ingress of water.
This installation has been performed via a controlled Work Order.
The caulking material used was Chem Caulk 900.
Additionally, the area around the RWT has been regraded to prevent standing water from rising to a level above the top of the ring wall foundation (Reference 9.12).
Elimination of water from the sand layer beneath the tank will arrest further galvanic corrosion by eliminating the conductive electrolyte in contact with the tank floor and the ground grid.
Further corrosion due to the presence of salts in the sand layer will be minimal if further water ingress is prevented.
6 ~ 0 6.1 As stated in Section 4.4, in approving Relief Request No.
- 13A, the NRC stated that FPL had committed to performing visual examinations of the liner material during each refueling outage.
The Spring 1996 refueling outage was the first scheduled outage after the installation of the liner.
The commitment for the examinations would have been satisfied by performing a remote visual inspection (e.g., utilizing a diver or a remotely operated submersible vehicle equipped with a camera).
However, it was decided to completely drain the RWT and perform a complete hands-on inspection of the liner for the following reasons:
a ~
b.
To evaluate more completely the performance of the installed liner.
To obtain sufficie'nt data to support the request for approval of the liner as a permanent repair to the tank bottom.
Prior to the Spring 1996 Unit 1 refueling outage, a safety evaluation was prepared to provide the following information (Reference 9.13):
a.
Procedures and acceptance criteria for the inspection of the vinyl ester liner installed on the RWT bottom.
St. Lucie,Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 7
b.
c ~
Contingencies for minor repairs to be performed if the acceptance criteria for the inspections were not met.
A 10CFR50.59 evaluation demonstrating that the above activities do not constitute an unreviewed safety question or require a
change to the Technical Specifications.
On May 18,
- 1996, during the Spring 1996 Unit 1 refueling outage (SL1-14),
an inspection of the bottom liner of the RWT was performed.
The liner was inspected for acceptability of the following properties:
a ~
b.
c ~
d.
e.f.
gh.i k.l.
Hardness Delamination Adhesion Peeling Flaking Undercutting Blistering Cracking Checking Discoloration Holidays Pinholes The inspections performed on the RWT liner were non-destructive in nature.
The majority of the inspections were visual only.
Some of the inspections (i.e.,
- hardness, undercutting) involved the application of pressure with the edge or point of a knife or paint scraper; this did not result in any cutting of the liner surface.
The inspections for delamination and adhesion involved physical sounding, in which the liner surface was struck with a hammer.
The liner was only struck hard enough to enable the inspector to listen to-the sound made; the force applied was insufficient to cause any damage to the liner.
The installed liner was found to be acceptable.
The liner met the acceptance criteria for all of the properties listed
- above, and showed no signs of degradation which could affect its ability to perform its required functions.
There were two minor conditions found which warranted additional investigation, as noted below:
a ~
At one location, a small hole (diameter approximately 1/32 inch) was found.
Upon excavation, the hole was found to be less than 1/16 inch
- deep, and did not penetrate through the topcoat layer.
No path was found for water from the RWT to penetrate through the liner material.
Therefore, the condition was considered to be
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 8
an installation
- anomaly, and was not classified as a
pinhole.'or these
- reasons, the as-found condition was determined to be acceptable.
The excavated area was
- sanded, cleaned with an alcohol wipe, and filled in with Duromar SAR-UW.
This repair left the total coating thickness in the area of the anomaly equivalent to that of the remainder of the liner.
b.
At one location, a small amount of duct tape was found to have been left on the RWT wall and covered by the Protecto-Line topcoat.
The tape was completely covered by the liner material, and was completely restrained by the liner from becoming dislodged.
The duct tape had originally been placed on the wall for temporary attachment of shielding materials.
The tape was removed by cutting the liner with a knife, removing the liner material from above the tape, and removing the tape.
Additional liner material was removed to accommodate the installation of a vortex suppressor (Reference 9.14).
The liner material near the cut line was sanded and wiped with alcohol; the surface of the newly exposed aluminum was prepared in accordance with SSPC-SP-11.
Duromar SAR-UW epoxy was then placed with a 1" (minimum) overlap on both the liner and the aluminum to provide a seal at the cut line.
The complete report of the results of the liner inspection, including the additional investigations described above, is documented in Reference 9.15.
6.2 As discussed in Section 5.2, a caulking compound has been installed between the RWT bottom and the concrete ring wall foundation to prevent further ingress of water.
This caulking installation is required to be inspected on an annual basis to verify that the corrective measures continue to prevent ingress of standing or rain water beneath the RWT.
The first required inspection was performed on August 26, 1996.
Visual inspection was performed at the interfaces between (a) the base of the RWT and the asphalt and (b) between the asphalt and the concrete RWT foundation.
These inspections revealed minor defects in the caulk layers.
These defects consisted of pitting (small holes, less than 1/16" diameter) and minor separation (approximately 1/32" wide) between the caulk and the adjacent surfaces.
The extent of the defects was not sufficiently large to have created a potential for ingress of substantial amounts of water beneath the RWT.
- However, in order to prevent future problems in this area, the caulk at
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 9
the interfaces (a) between the base of the RWT and the asphalt and (b) between the asphalt and the concrete RWT foundation was repaired as necessary.
This installation was re-inspected on September 12,
- 1996, and was determined to be satisfactory for the prevention of ingress of standing or rain water beneath the RWT.
The complete report of the inspection and re-inspection is documented in Attachment 12.5 of Reference 9'6.
6.3 Dudick, Inc.,
has published test values for the following physical properties of the Protecto-Line 800 liner system (Reference 9.9):
Adhesion strength Ability to bridge holes up to 0.5" in diameter Specific gravity Ability to accommodate "oil canning" Effects of radiation exposure on tensile bond test results Resistance to 5,000 ppm boron concentration Compressive strength Coefficient of thermal expansion Taber abrasion Flame spread Water vapor transmission Electrical resistance Discussion of these properties, including any laboratory testing performed to confirm the capabilities of this liner material with regard to its use in the Unit 1 RWT, is provided in the following paragraphs.
(a)
Two sets of adhesion strength tests were performed at FPL's CSI laboratory in West Palm Beach, Florida, on January 3 and 30, 1995.
Adhesion tests were performed in accordance with ASTM D4541-93.
Test samples were prepared by applying Dudick Protecto-Line 800 (using the same batches as were applied to the RWT bottom) to aluminum plates of the same material as specified for the RWT.
The coating was applied in individual layers (primer, basecoat, mat, topcoat) which were exposed at different strips along the test plate.
Loading fixtures were attached to the surface of the liner test samples using an epoxy adhesive.
The portable tester used was an Elcometer Model No.
106 (0-2,000 psi).
The pulling force was applied
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 10 through the Elcometer testing apparatus to the loading fixture until failure occurred.
Special care was taken to turn the wrench in a plane parallel to the substrate to avoid the application of shear loads or other eccentric loads.
The failure loads (in psi) and nature of failure were also recorded.
A total of 32 loading fixtures were tested for pull-off strength.
The summary of these tests is as follows:
Date of Test 1/3/95 1/30/95 1/3/95 1/30/95 1/3/95 1/30/95 1/3/95 1/30/95 System Component Primer Primer Mat Mat Base Coat Base Coat Top Coat Top Coat Number of Tests Average Pull-Off Strength 500 psi 233 ps1 400 psi 200 psi 500 psi 550 psi 600 psi 620 psi All of the failures of the test specimens were a result of failure of the glue attaching the test fixtures to the sample panel.
No adhesion or cohesion failures of the coating were observed.
Dudick has published test data (Attachment 12.11 to Reference 9.16) indicating that the tensile bond strengths of the Protecto-Line 800 liner components are as follows:
a.
Base coat (adhesion to primed aluminum):
750 psi b.
Top coat (adhesion to total system):
1050 psi During the testing, the glue bonding the loading fixtures to the liner generally failed before the above loads could be applied.
Therefore, it was not possible to confirm the adhesion values published by Dudick.
- However, some of the individual tests performed exceeded the published values.
It may be concluded that higher adhesion values could have been obtained if a stronger glue had been available.
The test values obtained are sufficient to ensure that the coating will
r St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 11 not suffer adhesion or cohesion failure.
Therefore, the values obtained during the testing indicate that the Dudick Protecto-Line 800 system has sufficient adhesion and cohesion strength to perform its intended functions as a liner for the St. Lucie Unit 1 RWT.
The complete reports of these tests are documented in Attachments 12.6 and 12.7 of Reference 9.16.
(b)
II Three sample plates were tested at FPL's CSI laboratory in West Palm Beach, Florida, on January 3 and 30, 1995.
Tests were performed to evaluate the ability of the liner material to span over holes of 1", 2",
and 3" diameters.
Holes of these sizes were drilled in the test plates, and then covered with tape, prior to application of the liner material.
After the liner material had cured, the tape was removed from the underside of the cured liner material; this left holes in the plates over which the liner spanned.
This set-up replicates the hypothetical situation in which the aluminum plate deteriorates after the application of the liner.
Loads were applied to the liner material spanning the holes to simulate the loads which would result from water pressure at the bottom of the RWT.
The table below lists the loads applied to the liner for each hole size, and the margin of safety with regard to postulated loading conditions (i.e., the ratio between the test loading applied and the load which the liner would have to carry jZL~ at the bottom of the RWT).
Hole Size 2 Il 3 II Test Load Applied 140 lbs 150 lbs 220 lbs In-Situ Load
- 13 lbs 53 lbs 119 lbs Margin of Safety 2.8 1.8
- The water pressure at the bottom of the RWT is 16.9 psi (Reference 9.17).
Therefore, the in-situ load to be carried by the liner spanning over a postulated hole is equal to 16.9 psi multiplied by the area of the hole.
For each hole size tested, the loads that were applied during laboratory testing did not cause failure (either by structural
0
St. Lucie Unit, 1 Docket No. 50-335 L-96-329 Enclosure Page 12 failure or by adhesion/cohesion failure) of the test sample.
No deflection or visual signs of distress of the liner material was observed.
Therefore, the actual margin of safety of the liner material is higher than the values determined above.
The conclusion reached from this test is that the Dudick Protecto-Line 800 system liner material, in its application in the St. Lucie Unit 1 Refueling Water Tank, can span over holes up to 3
inches in diameter with a satisfactory margin of safety.
The complete report of these tests is documented in Attachment 12.8 of Reference 9.16.
(c)
A sample of the Dudick Protecto-Line 800 liner material was applied to a removable plastic medium and allowed to cure.
When curing was complete, the liner system was removed from the medium.
A sample was then cut from this material, and the dimensions and weight were measured and recorded.
These measurements were taken at FPL's CSI laboratory in West Palm
- Beach, Florida, on January 3,
1995.
From the measurements
- taken, the volume of the sample was determined to be 2861 mm, while the weight was measured as 4.86 grams.
From this, the specific gravity of the liner sample was determined to be 1.7 (greater than that of water in the RWT).
As a confirmatory test, a sample of liner material was placed into a beaker of tap water.
Several different orientations were used (i.e., the sample was placed onto the surface of the water with the flat surface horizontal as well as vertical).
Each time the sample was placed into the water, it sank immediately to the bottom of the beaker.
This confirms the claim of Dudick, Inc., that the specific gravity of the Protecto-Line 800 liner is greater than that of water.
This result confirms the original conclusion (Reference 9.9) that, if any liner material installed in the RWT were to come loose, it would remain on the bottom of the tank and not be drawn into suction penetrations (as stated in Reference 9.9, the fluid velocities in the vicinity of the penetration are very low and insufficient to draw any significant debris off the bottom of the tank).
The complete report of these tests is documented Reference 9.16.
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 13 (d)
In Letter No. JPN-CSI-95-045 (Reference 9.18),
documentation was provided of the observation of "oil canning" of the bottom plates of the RWT after the application and curing of the Dudick Protecto-Line 800 system.
This "oil canning" was caused by the weight of personnel walking on the tank bottom which had distended upward when the weight of the water normally stored in the tank had been removed.
The effect was observed to be applied cyclically (i.e.,
downward deflection when an individual stood on a floor panel, with the panel returning to its original position when the weight of the individual was removed.
This "oil canning" was observed to be of a magnitude approximating 3 to 4 inches.
No cracking, disbondment, or other signs of distress in the liner were observed as a result of this occurrence.
Similar observations (both of the extent of "oil canning" and of the absence of distress in the liner) were made during the inspection of the RWT liner on May 18, 1996.
Therefore, it is concluded that the Protecto-Line 800 liner will not be adversely affected by the "oil canning" effect resulting from the cyclic removal and addition of loads on the RWT bottom plates (i.e., the draining and filling of the tank).
(e)
An aluminum test panel coated with the Dudick Protecto-Line 800 system was submitted to SteriGenics, Inc.,
who subjected this test panel to an exposure of 107,100,000 Rads (Attachments 12.11 and 12.14 of Reference 9.16).
This is greater than the projected total dose to the RWT bottom, which is estimated to be 35,000 Rem overall or 350,000 Rem at hot spots (Reference 9.19).
The irradiated panel was then provided to Dudick, who performed adhesion tests in accordance with ASTM D4541.
The results of this testing were identical to previous tests, thus verifying that the radiation exposure had no effect on the tensile bond strength of the liner material (Attachment 12.11 of Reference 9.16).
After testing, the test panel was returned to FPL.
The FPL Coatings Specialist performed confirmatory adhesion testing in accordance with ASTM D4541-93 on the irradiated sample received from Dudick (Reference 9.20).
All of the failures of the test specimens were a result of failure of the glue attaching the test fixtures to the sample panel; in each
- case, the applied load at failure was between 500 and 750 psi.
No adhesion or cohesion failures of the coating were observed.
The values obtained during the testing indicate that the
ll
St. Lucie Unit 1 Docket No..50-335 L-96-329 Enclosure Page 14 Dudick Protecto-Line 800 system maintains sufficient adhesion and cohesion strength to perform its intended functions as a
liner'for the St. Lucie Unit 1 RWT.
Dudick, Inc.,
recommends the Protecto-Line 800 fiberglass reinforced vinyl ester liner system for applications involving concentrated acid spills, acid neutralization, and caustic handling areas.
General-purpose polyester resins reinforced with fiberglass have good chemical resistance, except to alkalies; however, materials in this class which are based on bisphenol are more resistant to alkalies (Reference 9.21, page 23-61).
General-purpose polyesters have good to excellent chemical resistance to 104 solutions of hydrochloric, sulfuric, nitric, and acetic acids (Reference 9.21, Table 23-9).
Also, polyesters have excellent resistance to mineral acids such as boric acid (Reference 9.21, Table 23-11).
Even at 5,000 ppm, the concentration of boric acid in water is very dilute (much less than 104).
Therefore, from the industry data and historical information referenced in the paragraph.
- above, the Protecto-Line 800 liner material will adequately resist a boron concentration of 5,000 ppm.
Makeup to the RWT is supplied via a blended flow of reactor makeup. water from the Primary Water Tank and boric acid (approximately 34 concentration) from the Boric Acid Makeup Tanks (Reference 9.22).
This combination yields the Technical Specification required RWT concentration of 1720 ppm boron (approximately 1% boric acid).
This is much less than the 104 concentration evaluated above.
Therefore, the Protecto-Line 800 liner material will adequately resist the boron concentration present in the RWT.
Visual inspection performed on May 18, 1996 (Reference 9.15) indicated no changes in the physical attributes of the installed liner; this is a primary indication of chemical resistance.
(g)
The water pressure at the bottom of the RWT is 16.9 psi (Reference 9.17).
Because of this low uniform load to be
- carried, and the absence of concentrated loads on the RWT bottom, it was concluded that compressive strength is not a critical property for the liner material.
- However, subsequent tests were performed to verify that the liner material can
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 15 withstand, with an adequate safety
- margin, the uniform compressive loads to which it will be subjected in the RWT.
Two samples of Dudick Protecto-Line 800 material were subjected to compression testing in FPL's Research and Evaluation laboratory in West Palm Beach, Florida, on August 28, 1996.
The compression loads were applied with a Tinius Olsen 5000 pound universal testing machine.
The complete report of this testing is documented in Attachment 12.13 of Reference 9.16.
The samples were placed in the testing machine between parallel plates.
A thin piece of rubber blanket was placed on top of the sample to smooth out any irregularities.
The sample was compressed in 1,000 pound increments at a rate of approximately 1,000 pounds per minute.
At each increment, the sample was removed and visually examined for signs of failure.
The first sample tested measured 1.1" by 1.117", with an area of 1.23 in.
The maximum compressive load applied to this sample was 5030 pounds, which resulted in a compressive stress of 5030/1.23, or 4090 psi.
The second sample tested measured 1.124" by 1.126",
with an area of 1.27 in.
The maximum compressive load applied to this sample was 5021 pounds, which resulted in a compressive stress of 5021/1.27, or 3950 psi.
Neither test sample showed any signs of failure at the maximum load.
Therefore, the margin of safety for the liner material with regard to compressive strength is at least 3950/16.9, or 234.
The test values obtained indicate that the Dudick Protecto-Line 800 system has sufficient, compressive strength to perform its intended function as a liner for the St. Lucie Unit 1 RWT.
(h)
From information published by Dudick, Inc., the coefficient of expansion for the Protecto-Line 800 system is 12-15 x
10 inch/inch/'F (Attachment 4.4 of Reference 9.9).
The coefficient of thermal expansion for aluminum is 12.8 x 10 inch/inch/'F (Reference 9.23, p.
19-46).
The values of the coefficient of thermal expansion for the two materials are approximately equal.
The assumed minimum temperature of the water in the RWT is 55'F (Reference 9.3, Table 6.3-6).
The design temperature of the water in the RWT is 125'F (Reference 9.3, Table 6.3-2).
Because of this limited temperature
- range, the coefficient of thermal expansion is not a critical property.
Over a 50 foot length (the diameter of the RWT),
a strip of aluminum subjected to a
70'F temperature increase would increase in
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 16 length by only (12.8 x 10 in/in/'F) x (50x12 in) x (70'F), or approximately 1/2 inch.
Even a
major variance in the coefficient of expansion of the liner material would not result in a large differential expansion between the liner and the aluminum; therefore, the value of the coefficient of thermal expansion does not need to be verified.
Water vapor transmission (WVT) is a measure of the rate at which water vapor can be transmitted through a coating.
This property is generally used as a guide in the selection of coatings (i.e., paint) which are normally applied to a dry film thickness (DFT) of 10-20 mils and which would be more susceptible to blistering.
The value of WVT published by Dudick for the Protecto-Line 800 system (0.0017 perm. in.) is very low.
Because of the high DFT (125 mils or greater) of the liner system, and the low WVT rate, the Protecto-Line 800 system is not susceptible to osmotic blistering.
Therefore, the water vapor transmission rate does not need to be verified.
Because of the nature of this application of the liner material (i.e., underwater on the non-traffic-bearing interior surfaces of the non-structural bottom plates of a
water storage tank),
verification of the properties of Taber
- abrasion, flame
- spread, and electrical resistance is not required.
6.4 Samples of the materials used in the application of the Protecto-Line 800 system (primer, coating, filler, hardener, and fiberglass roving) were sent to Professional Service Industries (Pittsburgh Testing Lab Division) for chemical analysis.
The intent of this analysis was to confirm the composition of the liner materials, and to determine whether the amounts of impurities in the materials are within the limits specified in FPL Administrative Procedure 0010507 (Reference 9.24) for materials used in the primary system.
To analyze the composition of the liner materials, infrared spectroscopic analysis was performed on samples of the basecoat and the filler material.
The spectrum of the basecoat material appeared to represent a mixture of materials from which typical vinyl esters are formed.
The spectrum of the filler material was determined to be similar to several siliceous materials.
From this analysis, it was concluded
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 17 that the chemical composition of the two samples agreed with the description published by Dudick, except that the basecoat sample did not contain silica.
This conclusion was as expected; although the purchase requisition describes the basecoat as being a "vinyl ester resin with graded silica",
the silica is a separate filler which is added at the time of application, and would not have been present in the basecoat material analyzed.
Therefore, the results of this analysis confirm that the liner material is in conformance with the published description.
Tests were also performed to determine the concentration of halogens (chloride, fluoride, bromide, and iodide), sulfur, and metals (mercury.
- cadmium, and phosphorus) present in the liner materials.
These impurities are as identified in Reference 9.24.
The testing was performed using recognized ASTM and EPA standards and inductively coupled plasma spectroscopy.
This testing indicated that the levels of all impurities (except for chloride and sulfur) in each of the liner components were within the acceptable limits.
The levels of chloride and sulfur were above the acceptable limits.
These results were obtained from the testing of the individual component elements of the Protecto-Line system.
When these components are mixed together to form the applied liner, the reactions between the elements change the final chemical composition of the liner.
For this reason, the levels of impurities in the component elements are not necessarily indicative of the levels to be found in the final system; the chemical reactions could cause the concentrations of the free elements to be reduced.
Since the levels of impurities (except chloride and sulfur) in each of the liner components were within the acceptable limits, it was concluded that the levels of these impurities in the liner are acceptable.
Further investigation of total chloride and sulfur levels was required.
The complete report of the chemical analysis performed by Professional Service Industries (Pittsburgh Testing Lab Division) is documented in Reference 9.25.
Additional tests were performed on a
sample of the cured Protecto-Line 800 system liner to determine total chloride, total sulfur, and leachable chloride.
This testing was performed at the FPL Central Testing Laboratory in West Palm Beach on August 28 and 29, 1996.
A sample of the liner was burned in a Parr Oxygen Combustion Bomb.
the bomb washings were then analyzed for chloride and sulfate by ion chromatography (EPA Method 300.0).
The test results indicated that the total sulfur content of the cured liner material was 87
- ppm, which is within the acceptable limit of 100 ppm.
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 18 Total chloride was determined to be 460
- ppm, which is above the specified limit of 100 ppm.
For the vinyl ester
- liner, the,total chloride is not an appropriate measure of the amount of chloride that can come into contact with the primary system.
In compounds of this
- nature, the majority of the chloride is bound within the matrix of the cured liner material; the only chloride that can come into contact with the primary system is that which can leach out of the cured chemical compound.
For this reason, an additional test was performed to determine the amount of leachable chloride in the liner material.
For this test, a
sample of the cured liner was leached in ionized water and boiled for one hour.
After cooling, the water was analyzed by ion chromatography.
This test indicated that the concentration of leachable chloride in the cured liner material is 83 ppm; this is within the acceptable limit of 100 ppm.
The use of leachable chlorides as an indicator is an accepted practice within the nuclear coatings industry.
The complete report of the testing performed at FPL's Central Testing Laboratory is documented in Reference 9.26.
The results of the chemical tests performed by Professional Testing Industries and FPL's Central Testing Laboratory indicate that the Dudick Protecto-Line 800 liner is composed of the materials specified by Dudick, Inc.,
and that the levels of impurities in the material are within the acceptable limits as specified in Reference 9.24.
7 '
7.1 The RWT was designed in accordance with ANSI B96.1, "Welded Aluminum Alloy Field Erected Storage Tanks".
The main base plates are 0.25 inches thick, and are welded to a 0.375 inch thick annular base plate.
The tank is supported on an 8.5'igh by 2'ide reinforced concrete ring wall foundation.
The RWT base is anchored to the ring wall foundation with 45 two-inch diameter ASTM A36 carbon steel anchor bolts.
(References 9.27 and 9.28)
The RWT bottom plates are continuously supported by structural fill material.
There is a
6" thick sand and oil cushion placed on approximately 8 feet of Class I fillcompacted to 95% of maximum dry density; underlying this is Class I fill compacted to 98: of maximum dry density (Reference 9.22).
The tank shell is supported directly by the concrete ring wall and does not depend on the bottom plate for structural support.
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 19 Per ANSI B96.1, the flat bottom of the tank is not subject to specific design rules for calculating minimum thickness and allowable stresses are not given for the tank bottom.
The function of the bottom plate is to provide a barrier between the tank fluid and the underlying fillmaterial.
The bottom plate does not transfer loads to the shell or the annular base plate and ring wall foundation.
Pressure stress loads are carried by the fillbeneath the tank bottom.
Therefore, the tank bottom may be considered a liner.
During the various repairs made to the RWT bottom, the support conditions of the bottom plate have not been changed from the original design.
7.2 As discussed in Section 6.3, FPL has performed confirmatory testing to verify the manufacturer's published information concerning the physical properties of the Dudick Protecto-Line 800 system.
These test results provide the necessary confirmation of the ability of the Dudick system to perform its intended functions as a liner for the St.
Lucie Unit 1 RWT.
As discussed in Section 6.4, FPL has performed chemical testing to confirm the composition of the liner materials.
The results of this testing indicate that the Protecto-Line 800 liner system is composed of the materials specified by Dudick, Inc.,
and does not exceed the acceptable limits for impurities as specified by FPL Administrative Procedures for materials in contact with the primary system.
The fiberglass-reinforced vinyl ester liner was installed during the Fall 1994 refueling outage.
During the Spring 1996 refueling outage, the RWT was drained and a full hands-on visual inspection of the liner was performed.
As discussed in Section 6.1, the liner met the acceptance criteria for all properties evaluated during this inspection, and showed no signs of degradation which could affect its ability to perform its required functions.
As discussed in Section 5.0, FPL has performed a root cause analysis of the tank bottom corrosion mechanism.
The failure mechanism was determined to be galvanic corrosion resulting from a galvanic couple between the exterior surface of the RWT floor and the surrounding copper ground grid.
The root cause of the failure was determined to be the absence of a seal between the tank bottom plates and the concrete ring wall, which permitted the periodic ingress of water beneath the
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 20 tank.
Corrective action has been taken to eliminate this root cause by installing a joint sealing compound between the tank bottom plates and the ring wall.
Additionally, the area around the RWT has been regraded to prevent standing water from rising to a
level above the top of the ring wall foundation.
By preventing further ingress of water beneath the RWT, further corrosion of the tank bottom due to the presence of salts in the sand layer will be minimal.
For the reasons discussed
- above, the Dudick Protecto-Line 800 system has been determined to be an appropriate material to be used as a liner for the aluminum RWT.
Visual, inspections have indicated no degradation of the material since installation.
Since the tank bottom does not transfer loads to the shell or to the annular base plate and ring wall foundation, it is considered a liner (i.e.,
a barrier between the tank fluid and the underlying fillmaterial) in accordance with ANSI B96.1 (the design Code of record).
Therefore, the installed Dudick Protecto-Line 800 liner is considered an alternative design which is equivalent to the design originally installed per the Code of record (ANSI B96.1),
and will provide an acceptable level of quality and safety.
The liner material extends approximately 24 inches up the tank wall, which is a structural, load carrying element of the tank.
As indicated in Section 6.3(d), the liner has exhibited the ability to accommodate approximately 3 to 4
inches of deflection on the tank bottom.
This exceeds any bending deflection which will be experienced in the lowest 2 feet of the tank wall under postulated loading conditions.
Therefore, loads causing stresses and accompanying deformations in the RWT wall will not result in loss of adhesion of the liner material to either the tank wall or the bottom.
The installed Protecto-Line 800 liner system meets quality standards commensurate with the importance of the safety function to be performed (i.e., acting as a liner to retain the water in the RWT), as indicated by the following:
a ~
The liner was installed in accordance with Reference 9.9, which is a safety-related Engineering Package.
b.
The liner material has been subjected to physical and chemical tests (as discussed in Sections 6.3 and 6.4) to confirm its ability to perform its intended functions as a liner for the RWT.
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 21 c.
FPL is proposing an augmented inspection program to provide ongoing verification that the liner will continue to adequately perform its intended functions.
8 '
8.1 Florida Power and Light proposes to use the installed fiberglass-reinforced vinyl ester liner (Dudick Protecto-Line 800 system) in place on the Unit 1 Refueling Water Tank (RWT) bottom as a permanent alternative design, and also proposes to continue to use the RWT to meet its required Technical Specification functions.
The Unit 1
Updated Final Safety Analysis Report (FSAR)
(Reference 9.3),
Section 6.3.2.2.1, states that the NRC has approved the liner "as an alternative non-Code repair until the steam generator refueling outage, at which time a Code repair shall be made".
An FSAR Change Package (FCP) has been prepared to delete the requirement to perform a
Code repair at the time of the steam generator replacement outage.
Upon NRC approval of the use of the liner as a
permanent installation, the Updated FSAR will be updated to incorporate this FCP.
8.2 The following inspections will be performed during the period beginning with the Steam Generator Replacement outage and for the subsequent ten years (i.e., through the third ten-year ISI interval, which ends on February 11, 2008).
a ~
Beginning with the SL1-17 refueling outage (the second outage following the Steam Generator Replacement outage),
and during every third subsequent refueling outage (i.e.,
approximately every 4-1/2 years),
a full inspection of the RWT liner will be performed.
For these inspections, the RWT will be completely drained; inspectors will enter the tank to perform a
hands-on inspection.
These inspections will be similar to the inspection performed during the Spring 1996 refueling outage (SL1-14).
The liner will be inspected for acceptability of the following properties:
Hardness Delamination Adhesion Peeling
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 22 Flaking Undercutting Blistering Cracking Checking Discoloration Holidays Pinholes b.
Beginning with the SL1-15 outage (the Steam Generator Replacement outage),
and during every refueling outage for which a full inspection of the RWT liner is not scheduled, a
remote visual inspection of the liner will be performed.
These remote inspections may be performed with the use of a diver or a remotely operated submersible vehicle equipped with a
camera.
During these inspections, the liner will be visually examined for:
Peeling Flaking Undercutting Blistering
- Cracking, The proposed inspection schedule outlined above is applicable through the end of the third ten-year ISI interval.
A separate submittal will be made to the NRC regarding a
proposed inspection schedule for the period beginning with the fourth ten-year ISI interval (which begins on February 12, 2008).
The proposed inspection schedule for the fourth ten-year ISI interval will be based on the results of inspections performed up to the time of the submittal.
Should any RWT liner inspections indicate unacceptable
- results, or if there are any documented occurrences of leakage through the RWT bottom, the inspection schedule (and types of inspections required) shall be revised as follows:
a full hands-on inspection shall be performed during the first refueling outage following the unacceptable inspection results or documented leakage and during every third refueling outage thereafter for the remainder of the third ten-year ISI interval.
See Table 1 for summary of proposed augmented inspections.
8.3 The conditions at the bottom of the RWT shall be inspected on an annual basis to verify that.
the corrective measures implemented (i.e.,
the caulking material between the RWT
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 23 bottom and the concrete ring wall) continue to prevent ingress of standing or rain water beneath the RWT (Reference 9.17).
9 ~ 0 9.1 9.2 St. Lucie Unit 1 Technical Specifications, through Amendment 14.
ANSI B96.1-1967, "Welded Aluminum Alloy Field Erected Storage Tank 9.3 St. Lucie Unit 1 Updated Final Safety Analysis Report, through Amendment 142.
9.4 9.5 9 '
9.7 Generic Letter No. 90-05, "Guidance for Performing Temporary Non-Code Repair of ASME Code Class 1,
2, and 3 Piping", dated June 15, 1990.
A.
Sager to U.
S.
Nuclear Regulatory Commission, dated July 30, 1993 U.
S.
Nuclear Regulatory Commission letter from Herbert N.
Berkow to Mr. J.
H. Goldberg, dated October 21, 1993 Letter No. ESI-NDE-93-172, from C.
M. Redding/S.
M. Alberico to A. G. Menocal, "Final Report of the Refueling Water Tank, St. Lucie Unit 1, August 1993",
prepared by Florida Power Light
- Company, Nuclear Engineering,
- ESI, dated August 13, 1993.
9.8 9.9 Letter MET-94-227 from Mark Joseph (FPL Component Support and Inspection Group) to Dan Denver (FPL Nuclear Engineering),
dated January 19, 1995.
PC/M No. 128-194, "Addition of a Reinforced Vinyl Ester Liner to the Bottom of the Refueling Water Tank", Revision 1.
9.10 FPL Letter L-94-291 from D.
A.
Sager to U.
S.
Nuclear Regulatory Commission, dated November 16, 1994.
9.11 Letter from Mohan C.
Thadani (NRR) to Mr. J.
H.
Goldberg (FPL),
"Proposed Alternative to the ASME Code for Replacement of the Refueling Water Tank Bottom at St.
Lucie Unit No.
1 (TAC No. M90762)", dated November 25, 1994 9.12 Nonconformance Report (NCR) No. 1-741, dated January 22, 1993.
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 24 9.13 Safety Evaluation No.
JPN-PSL-SECP-96-053, "Inspection Procedures and Repair Contingencies for the Refueling Water Tank Bottom Liner", Revision 0.
9.14 PC/M No.96-085, "Refueling Water Tank Vortex Suppressor",
Revision 0.
9.15 Letter JPN-SPSL-96-0245 from D.
J.
Denver (FPL Nuclear Engineering) to H.
L.
Fagley (FPL Projects Maintenance Support),
dated May 23, 1996 9.16 Safety Evaluation No.
JPN-PSL-SECS-96-082, "Refueling Water Tank Alternative Bottom Design", Revision 0.
9.17 St. Lucie Action Report (STAR) No. 1-94110485, dated November 21(
1994.
9.18 Letter JPN-CSI-95-045 from G.
S. Dolderer (JPN/CSI) to K. H.
Greene (JPN/PEG),
dated February 3,
1995.
9.19 Letter No.
BK f93-021 from Ray McCullers (St.
Lucie Health Physics) to Garth Dolderer (JPN/JB),
dated September 22, 1993.
9.20 Letter JPN-CSI-96-113 from G.
S. Dolderer (ENG/CSI) to K. H.
Greene (ENG/PSL), dated September 12, 1996.
Gb '1~
Fifth Edition, McGraw-Hill Book Company, copyright 1973.
9.22 Safety Evaluation No.
JPN-PSL-SENP-93-035, "Evaluation of Inventory Loss from the Refueling Water Tank", Revision 2.
E Il~
1968.
9.24 FPL Administrative Procedure No.
- 0010507, "Control of Chemicals and Materials for the Maintenance of Plant Systems",
Revision 9.
9.25 Professional Service Industries, Inc.,
Test Report for Protecto-Line 800 Material for Florida Power
& Light Co.,
Project No. 831-5T084-1, dated March 6, 1995.
9.26 Florida Power and Light Central Laboratory Report of Analysis (Sample Identification: Dudick Protecto-Line 800; FPL Lab WITS ID: W-96-81), dated September 4,
1996.
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 25 9.27 Drawing No.
8770-4510, "Refueling Water Tank Bottom Details", Revision 4.
9.28 Drawing No. 8770-G-671, "Component Cooling Pumps Foundations Masonry", Revision 8.
St. Lucie Unit 1 Docket No. 50-335 L-96-329 Enclosure Page 26 TABLE 1 ST ~ LUCIE UNIT 1 -REFUELING WATER TANK PROPOSED SCHEDULE FOR INSPECTIONS FOR THE FIRST 10 YEARS AFTER STEAM GENERATOR REPLACEMENT OUTAGE REMOTE VISUAL INSPECTION FULL HANDS-ON INSPECTION SL1-15 X
SL1-16 SL1-17 SL1-18 SL1-19 SL1-20 SL1-21 X
X Note:
Should any RWT liner inspections indicate unacceptable
- results, or if there are any documented occurrences of leakage through the RWT bottom, the inspection schedule (and types of inspections required) shall be revised as follows: a full hands-on inspection shall be performed during the first refueling outage following the unacceptable inspection results or documented leakage and during every third refueling outage thereafter for the remainder of the third ten-year ISI interval.
0 A
~ 'g 1
J'
>v