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/NEA Moho Neh%nelEnp%een%g laboratory July 6,1995 Mr. Romas K. McLellan, Project Officer c/o Document Control Desk Civil Engineering & Geosciences Branch Division of Engineering U.S. Nuclear Regulatory Commission Washington, DC 20555 TRANSMITTAL OF THE TECHNICAL LETTER REPORT ON THE SECOND 10-YEAR INTERVAL INSERV)CE INSPECTION, REQUEST FOR RELIEF 19 FOR ST. LUCIE NUCLEAR PLANT, UNIT 2 - MTA-12-95
Reference:
NRC Form 189, " Technical Assistance in Support of the NRC Inservice inspection Program" (JCN-J2229, Task Work Assignment TWA-B16, NRC TAC No. M920l3)
Dear Mr. McLellan:
His report completes the INEL review of the subject request for relief for the second 10-year ISI interval at St. Lucie Nuclear Plant, Unit 2. His request was submitted by Florida Power and Light Company on April 3,1995.
His report completes the INEL work under Task Work Assigmcent TWA-B16 of NRC JCN-12229 for NRC TAC No. M92013.
Sincerely,
'k M. T. Anderson, Principal Investigator NDE Engineering Analysis and Applications MTA c.aclosure cc:
S. F. Armour, DOE-ID, MS 1219 G. Bagchi, NRR, MS 7H15 (w/o Enct)
D. Terao, NRR, MS 7H15 (w/o Encl)
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l ATTACHMENT 2 1
TECHNICAL EVALUATION LETTER ON THE SEC006 10-YEAR INTERVAL INSERVICE INSPECTION REQUEST FOR RELIEF NUMBER 19 FOR FLORIDA POWER Ale LIGHT COMPANY ST. LUCIE NUCLEAR PLANT, UNIT 2 DOCKET NUMBER: 50-389
1.0 INTRODUCTION
The licensee, Florida. Power and Light Company (FPL), submitted Request for Relief Number 19, for the second 10-year inservice inspection (ISI) interval, in a letter dated April 3, 1995. The Idaho National Engineering Laboratory j
(INEL) has evaluated the subject request for relief in the following section.
2.0 EVALUATION I
The Code of record for the St. Lucie Nuclear Plant, Unit 2, second 10-year inservice inspection interval, which began August 8,1993, is the 1989 Edition of the American Society of Mechanical Engineers,Section XI. The information provided by the licensee in support of the request for relief from the impractical requirement has been evaluated and the basis for granting relief from that requirement is documented below.
Reauest for Relief 19. Paraoraoh IWA-5242(a). Visual Examination of Insulated Components Code Reauirement:
Paragraph IWA-5242(a) requires that insulation be removed from pressure-retaining bolted connections for VT-2 visual examination on systems borated for the purpose of controlling reactivity.
I Licensee's Code Relief Reauest: The licensee requested interim relief from the removal of insulation on pressure-retaining bolted connections in borated systems during VT-2 visual examination for the upcoming refueling outage scheduled for September 1995.
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Licensee's Basis for Reauestina Relief (as stated):
"For systems borated for the purpose of controlling reactivity, removal of insulation from bolted connections for the purpose of perfoming a l
visual examination for corrosion will involve a significant increase in man hours, radiation exposure, and material.
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"The quantity of bolted connections which will require insulation removal and restoration, as determined by an initial review of drawings and other design documents, involves a significant increase in the amount of man hours and material. This hardship in turn, results in escalated operations maintenance costs, and radiation exposure, without a i
compensating increase in the level of quality and safety.
I "In an effort to minimize the impact of these examinations in the future, FPL will evaluate the feasibility and cost benefit of an insulation modification at applicable locations, such that an examination may be perfomed without the need to remove insulation each time. The evaluation of the feasibility of this modification, however, cannot be i
completed until a walkdown of the piping is performed. This walkdown cannot be performed at power.
"This interim relief will provide time to resolve the scope of these examinations through the ASME Code process and evaluate the results of system walkdowns conducted inside containment to detemine the feasibility of permanent design changes."
Licensee's Proposed Alternative Examination (as stated):
" Florida Power Light will check bolted connections for leakage when performing system examinations as follows:
"As soon as possible, after coming off line for a refueling outage, a leak test is coordinated by the system engineers inside the containment per the plant surveillance program.
"During the outage, suitcase style insulation will be removed from i
the Reactor Coolant and Charging systems inside containment, and the connections visually examined (VT-2) for evidence of leakage when the plant is depressurized. When evidence of leakage is identified, repairs will be performed in accordance with the current maintenance work practices.
"During the outage, any Class 1 or Class 2 insulated connections in the_ Reactor Coolant and Charging systems inside containment that are disassembled will be examined for evidence of leakage by maintenance personnel.
Repairs will be performed in accordance with the current maintenance work practices.
" Prior to reactor criticality, following a refueling outage, a system leakage test is performed at normal operating pressure and temperature with.a 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> hold time.
"These Leakage Tests will include looking for the following conditions:
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" pooling of water directly under the bolted connections; j
" water leaking from the lowest elevation section of vertical lines containing bolted connections; and "discolorization or residue on surfaces exsmined shall be given particular attention to' detect evidence of boric acid accumulations froe borated reactor coolant leakage."
Evaluation:
Paragraph IWA-5242(a) requires the removal of insulation from pressure-retaining bolted connections in borated j
systems for direct VT-2 visual examination during system pressure testing. The licensee noted that, based on an initial review of drawings and other design documents, the number of bolted j
connections requiring insulation removal will result in a significant increase in man hours, radiation exposure, and materials.
As an alternative to the removal of all insulation for the uncming refueling outage, the licensee has proposed to visually examini bolted connections, inside and outside of containment, during leakage tests as part of the plant surveillance program. During the outage, removable insulation (suitcase style insulation) will be removed from the reactor coolant and charging systems inside containment, and a VT-2 visual examination of the bolted connection will be performed. Where maintenance requires the removal of insulation on the reactor coolant and charging systems inside containment, maintenance personnel will look for evidence of leakage.
In addition, after refueling and prior to reactor criticality, the licensee will perform a VT-2 visual examination, following a 4-hour hold time, in conjunction with the leakage test at normal operating pressure. During this walkdown the licensee will look for evidence of leakage under bolted connections, water 4
leaking from the lowest elevation of vertical piping containing bolted connections, and pay particular attention to discolorization or residue on surfaces from borated reactor coolant leakage.
The INEL staff has reviewed the licensee's proposed alternatives to removal of insulatic t at bolted connections in systems tor'.ted for I
the purpose of controlling reactivity. Based on this evs.luation, it 3
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1 ij is concluded that requiring the licensee to remove insulation on all l
bolted connections in systems borated for the purpose of controlling reactivity during the upcoming refueling outage would result in a burden without a compensating increase in safety. The INEL staff believes that the licensee's proposed alternatives for the interim request for relief will provide reasonable assurance of operational readiness. Therefore, it is recommended that interim relief for the l
currently scheduled refueling outage in September, 1995, be authorized pursuant to 10 CFR 50.55a(a)(3)(ii) provided that for the upcoming September,1995, refueling outage, all removable insulation i
at bolted connections in borated systems is removed and a VT-2 l
visual examination is performed.
3.0 CONCLUSION
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j The INEL staff has reviewed the licensee's Request for Relief Number 19 and recommends that interim relief be authorized, pursuant to 10 CFR 50.55a(a)(3)(ii), for the upcoming St. Lucie, Unit 2, refueling outage, currently scheduled for September,1995, provided that all removable 3
j insulation is removed from bolted connections in borated systems and a VT-2 visual examination is performed.
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