ML20134N735
| ML20134N735 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  (DPR-42-A-126, DPR-60-A-118) |
| Issue date: | 02/19/1997 |
| From: | Wetzel B NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20134N738 | List: |
| References | |
| NUDOCS 9702240411 | |
| Download: ML20134N735 (28) | |
Text
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4 UNITED STATES
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NUCLEAR REGULATORY COMMISSION 2
WASHINGTON, D.C. 30eeH001
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NORTHERN STATES POWER COMPANY DOCKET NO. 50-282 PRAIRIE ISLAND NUCLEAR GENERATING PLANT. UNIT NO. 1 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No.126 License No. DPR-42 1.
The Nuclear Regulatory Comission (the Comission) has found that:
A.
The application for amendment by Northern States Power Company (the licensee) dated October 25, 1996, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act),
and the Comission's rules and regulations set forth in 10 CFR Chapter I; B.
The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Comission; C.
There is reasonable assurance (1) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Comission's regulations; D.
The issuance of this amendment will not be inimical to the comon defense and security or to the health and safety of the public; and E.
The issuance of this amendment is in accordance with 10 CFR~Part 51 of the Comission's regulations and all applicable requirements have been satisfied.
2.
Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility Operating License No. DPR-42 is hereby amended to read as follows:
9702240411 970219 PDR ADOCK 05000282 P
f 2-Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No.
126, are hereby incorporated in the license.
The licensee shall operate the facility in accordance with the Technical Specifications.
3.
This license amendment is effective as of the date of issuance, with full implementation within 30 days.
FOR THE NUCLEAR REGULATORY COMISSION du a.
Beth A. Wetzel, Project Manager Project Directorate 111-1 Division of Reactor Projects - III/IV Office of Nuclear Reactor Regulation
Attachment:
Changes to the Technical Specifications Date of Issuance: February 19, 1997
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ATTACHMENT TO LICENSE AMENDMENT NO. 126 FACILITY OPERATING LICENSE NO. DPR-42 DOCKET NO. 50-282 Revise Appendix A Technical Specifications by removing the pages identified below and inserting the attached pages. The revised pages are identified by amendment number and contain vertical lines indicating the area of change.
REMOVE INSERT TS-viii TS-viii TS.4.4-1 TS.4.4-1 TS.4.4-2 TS.4.4-2 TS.4.4-3 TS.4.4-3 TS.4.4-4 TS.4.4-4 TS.4.4-5 TS.6.5-8 B.4.4-1 B.4.4-1 B.4.4-2 B.4.4-2 B.4.4-3 B.4.4-3 B.4.4-4 B.4.4-4 B.4.4-5 i
l
i 4
TS viii TABLE OF CONTENTS (Continued)
TS SECTI M IlTjJ PACE 6.0 ADMINISTRATIVE CONTROLS TS.6.1 1 6.1 Organization TS.6.1-1 6.2 Review and Audit TS.6.2 1 A. Safety Audit Committee (SAC)
TS.6.2-1
- 1. Membership TS.6.2-1
- 2. Qualifications TS.6.2-1
- 3. Meeting Frequency TS.6.2-2
- 4. Quorum TS.6.2-2
- 5. Responsibilities TS.6.2 2
- 6. Audit TS.6.2-3
- 7. Authority TS.6.2-4
- 8. Records TS.6.2-4
- 9. Procedures TS.6.2-4 B. Operations Committee (OC)
TS.6.2-5
- 1. Membership TS.6.2-5
- 2. Meeting Frequency TS.6.2-5
- 3. Quorum TS.6.2-5
- 4. Responsibilities TS.6.2-5
- 5. Authority TS.6.2-6
- 6. Records TS.6.2-6
- 7. Procedures TS.6.2-6 C. Maintenance Procedures TS.6.2 7 6.3 Special Inspections and Audits TS.6.3 1 6.4 Deleted 6.5 Plant Operating Procedures TS.6.5-1 A. Plant Operations TS.6.5 1 B. Radiological TS.6.5-1 C. Maintenance and Test TS.6.5 4 D. Delete E. Offsite Dose Calculation Manual (ODCM)
TS.6.5-4 F. _Securit y TS.6.5 5 C. Temporary Changes to Procedures TS 6.5-5 H. Radioactive Effluent Controls Program TS.6.5-6 I. Explosive Gas and Storage Tank Monitoring Program TS 6.5 7 J. Containment Laakage Rate Testing Program TS.6.5-8 l
6.6 Plant Operating Records TS.6.6 1 A. Records Retained for Five Years TS.6.6 1 B. Records Retained for the Life of the Plant TS 6.6-1 i
Prairie Island Unit 1 - Amendment No. 422, 423, 126 Prairie Island Unit 2 - Amendment No. 145, 146, 118
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TS.4.4 1 4.4 CONTAINMENT SYSTEM TESTS Anolicability l
Applies to integrity testing of the steel containments, shield buildings, auxiliary building special ventilation zone, and the associated systems including isolation valves and emergency ventilation systems.
Obiective To assure that potential leakage from containment of either unit to the environs following a hypothetical loss of coolant accident in that unit is held within values assumed in the accident analysis.
Snecification A.
Containment Lankare Tests 1.
Perform required visual examinations and leakage rate testing in accordance with the Containment Leakage Rate Testing Program.
l 1
2.
Containment Airlock Leakage Tests Perform required containment air lock leakage testing in accordance with the Containment Leakage Rate Testing Program.
3.
Containment Isolation Valve Leakage Tests Perform required containment isolation valve leakage testing in accordance with the Containment Leakage Rate Testing Program.
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i Prairie Island Unit 1 Amendment No. 62, 126 Prairie Island Unit 2 Amendment No. 56, 118
- - _ _ ~
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5 9
i TS.4.4 2 B.
r=armancy Charcoal Filter Systems 1
1.
Periodic tests of the Shield Building Ventilation System shall be performed monthly to demonstrate OPERABILITY. Each redundant t
train shall be initiated from the control room and determined to be OPERABLE at the time of its periodic test if it meets drawdown performance computed for the test conditions with 75% of the i
shield building in leakage specified in Figure TS 4.4-1 after initiation and achieve a pressure 2.0 inches of water gage.
l 2.
Periodic test of the Auxiliary Building Special Ventilation i
System shall be performed at approximately quarterly intervals to j
demonstrate its OPERABILITY. Each redundant train shall be initiated from the control room and determined to be OPERABLE at j
the time of periodic test if it isolates the normal ventilation system and produces a measurable negative pressure in the ABSVZ within 6 minutes after initiation.
3.
At least once per operating cycle, or once each 18 months, 3
whichever comes first, tests of the filter units in the Shield Building Ventilation System and the Auxiliary Building Special i
Ventilation System shall be performed as indicated below:
1 a.
The pressure drop across the combined HEPA filters and 1
charcoal adsorbers shall be demonstrated to be less 6 inches of water at system design flow rate (1104).
b.
The inlet heaters and associated controls for each train shall be determined to be OPERABLE.
c.
Verify that each train of each ventilation system l
automatically starts on a simulated signal of safety injection and high radiation (Auxiliary Building Special Ventilation only).
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4.
a.
The tests listed below shall be performed at least once per operating 2
cycle, or once every 18 months whichever occurs first, or j
l after every 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of system operation or following i
l painting, fire or chemical release in any ventilation zone communicating with the system that could contaminate the HEPA filters or charcoal adsorbers.
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(1)
In place DOP and halogenated hydrocarbons tests at design flows on HEPA filters and charcoal adsorbers banks respectively shall show 1994 DOP removal for particles having a mean diameter of 0.7 microns and i
k994 halogenated hydrocarbons removal.
(2)
Laboratory carbon sample analysis shall show E906 4
i radioactive methyl iodide removal efficiency (130'C, 954 RH).
i 1
Prairie Island Unit 1 Amendment No. 62, 94, 126 Prairie Island Unit 2 Amendment No. 56, 84, 118 i
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l TS.4.4-3 b.
Cold DOP testing shall be performed after each complete or partial replacement of a HEPA filter bank or after any structural maintenance on the system housing that could
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affect the HEPA bank bypass leakage.
c.
Halogenated hydrocarbon testing shall be performed after each complete or partial replacement of a charcoal adsorber bank or after any structural maintenance on the system housing that could affect the charcoal adsorber bank bypass
- leakage, d.
Each circuit shall be operated with the heaters on at least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> every month.
5.
Perform an air distribution test on the HEPA filter bank after any maintenance or testing that could affect the air distribution within the systems. The test shall be performed at rated flow rate (ilot). The results of the test shall show the air distribution is uniform within 1204.
Contai aent Vacuum Breakers C.
D The air-operated valve in each vent line shall be tested at quarterly intervals to demonstrate that a simulated containment vacuum of 0.5 psi will open the valve and a simulated accident signal will close the
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valve. The check valves as well as the butterfly valves will be leak-tested in accordance with the requirements of Specification 4.4.A.3.
D.
Residual Hest Removal System 1.
Those portions of the residual heat removal system external to the isolation valves at the containment, shall be hydrostatically tested for leakage during each refueling shutdown.
2.
Visual inspection shall be made for excessive leakage from components of the system. Any visual leakage that cannot be stopped at test conditions shall be measured by collection and wei hing or by another equivalent method.
5 3.
The acceptance criterion is that maximum allowable leakage from either train of the recirculation heat removal system components (which includes valve stems; fisnges and pump seals) shall not exceed two gallons per hour when the system is at 350 psig.
4.
Repairs shall be made as required to maintain leakage within the acceptance criterion in Specification 4.4.D.3 5.
If repairs are not completed within 7 days, the reactor shall be shut down and depressurized until repairs are effected and the
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acceptance criterion in 3. above is satisfied.
Prairie Island Unit 1 Amendment No. 62, 445, 126 Prairie Island Unit 2 Amendment No. 56, 408, 118
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l TS.4.4-4 E.
Containment Isolation Valves l
During each refueling shutdown, the containment isolation valves, shield l
building ventilation valves, and the auxiliary building normal ventilation system isolation valves shall be tested for operability by applying a simulated accidant signal to them, j
F.
Post Accident Containment Ventilation System l
During each refueling shutdown, the. operability of system recirculating
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fans and valves, including actuation and indication, shall be demonstrated.
I G.
Containment and Shield Buildina Air Tennerature Prior to establishing reactor conditions requiring containment integrity, the average air temperature difference between the containment and its associated Shield Building shall be verified to be within acceptable limits.
H.
Containment Shell Ta-aerature Prior to establishing reactor conditions requiring containment integrity, the temperature of the containment vessel wall shall be verified to be within acceptable limits.
I.
Electric Hydroman Recembiners Each hydrogen recombiner train shall be demonstrated Operable at least once each refueling interval by:
a.
Verifying during a recombiner system functional test that the ei.nimum heater sheath temperatura increases to greater than or p 1 to 700'F within 90 minutes. Upon reaching 700*F, increase 05, power setting to maximum power for 2 minutes and verify that the power meter reads greater than or equal to 60kw.
b.
Verifying through a visual examination that there is no evidence of abnormal conditions within the recombiner enclosures (i.e.,
loose wiring or structural connections, deposits of foreign materials, etc.), and c.
Verifying the integrity of all heater electrical circuits by performing a resistance to ground test. The resistance to ground for any heater phase shall be greater than or equal to 10,000 ohns.
Prairie Island Unit 1 Amendment No. 68, 446, 126 Prairie Island Unit 2 Amendment No. 62, $99, 118
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TS.6.5 8 6.5.J. Containment Laakare Rate Testing Program i
A program shall be established to implement the leakage rate testing of the containment as required by 10 CFR 50.54(o) and 10 CFR 50, Appendix J, Option B, as modified by approved examptions. This program shall be in accordance with the guidelines contained in Regulatory Guide 1.163,
" Performance Based Containment Imak-Test Program," dated September 1995.
I The peak calculated containment internal precsure for the design basis loss of coolant accident is less than the containment internal design pressure, P.,
of 46 psig.
The maximum allowable primary containment leakage rate, L, at P.,
shall be 0.25% of primary containment air weight per day. For pipes connected to systems that are in the auxiliary building special ventilation zone, j
the total leakage shall be less than 0.1% of primary containment air we1 ht per day at pressure P., For pipes connected to systems that are i
5 exterior to both the shield building and the auxiliary building special ventilation zone, the total leakage past isolation valves shall be less than 0.01% of primary containment air weight per day at pressure P.,
Laakage Rate acceptance criteria are:
a.
Primary containment leakage rate acceptance criterion is 5 1.0 L.,
i Prior to unit startup, following testing in accordance with the program, the combined leakage rate acceptance criteria are 5 0.60 L, for all components subject to Type B and Type C tests and 5 0.75 L, for Type A tests; b.
Air lorL testing acceptance criteria are:
1)
Overall air lock leakage rate is 5 0.051, when tested at k46 psig 2)
For each door intergasket test, leakage rate is 5 0.01 L, when pressurized to E10 psig.
The provisions of 4.0. A do not apply to the test frequencies specified in the Containment Lankage Rate Testing Program. The Containment Leakage Rate Testing Program stipulates acceptable extension of test intervals.
The provisions of 4.0.B (except that the allowed surveillance intervals are defined by the Containment Leakage Rate Testing Program) are applicable to the Containment Leakage Rate Testing Program.
Prairie Island Unit 1 Amendment No. 126 Prairie Island Unit 2 Amendment No.118 1
e B.4.4-1 4.4 GDill'AllitfElfT SYSTEM TESTS SALLE The Containment System consists of a steel containment vessel, a con-crate shield building, the Auxiliary Building Special Ventilation Zone (ABSVZ), a Shield Building Ventilation System, and an Auxiliary l
Building Special Ventilation System. In the event of a loss-of-coolant accident, a vacuum in the shield building annulus will cause most leakage from the containment vessel to be mixed in the annulus volume and recirculated through a filter system before its deferred release to the environment through the exhaust fan that maintains vacuum. Some of the leakage goes to the ABSVZ from which it is exhausted through a filter. A l
small fraction bypasses both filter systems.
The freestanding containment vessel is designed to accommodate the r
maximum internal pressure that would result from the Design Basis Acci-dont (Reference 1).
For initial conditions typical of normal operation, 120*F and 15 psia, an instantaneous double-ended break with minimum safeguards results in a peak pressure of less than 46 psig at 268'F.
The containment was initially leak-tested at 46.0 psig to meet acceptance
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specifications.
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Maintaining the containment OPERABLE requires compliance with the visual l
examinations and leakage rate test requirements of theContainment Laakage Rate Testing Program. Failure to meet air lock leakage testing or aecondary containment bypass leakage testing criteris does not i
necessarily result in a failure to satisfy this surveillance requirement.
i The impact of the failure to meet any of these individual requirements must be evaluated against the Type A, B, and C acceptance criteria of the t
Containment Leakage Testing Program.
As left leakage prior to the first startup after performing a required i
leakage test is required to be 5 0.6 L, for combined Type B and C leakage, and 5 0.75 L, for overall Type A leakage. At all other times between required leakage rate tests, the acceptance criteria is based on an overall Type A leakage limit of s 1.0 L.,
At 51.0 L, the offsite dose consequences are bounded by the safety analysis. The surveillance i
testing frequency is stipulated by the Containment leakage Rate Testing Program.
Maintaining containment air locks OPERABLE requires compliance with the leakage rate test requirements of the Containment Leakage Rate Testing Program. This surveillance requirement reflects the leakage rate i
j testing requirements with respect to air lock leakage (Type B leakage tests). The acceptance criteria were established in the Safety Evaluation Report for License Amendment Nos. 62 and $6 dated February 23, 1983. The periodic testing requirements verify that the air lock leakage 4
does not exceed the allowed fraction of the overall primary containment j
leakage rate. The surveillance testing frequency is stipulated by the Containment Laakage Rate Testing Program, i
i Prairie Island Unit 1 Amendment No. 94, 407, 126 i
Prairie Island Unit 2 Amendment No. 84, $90,118 l
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B.4.4-2 4.4 CONTAINMENT SYSTEM TESTS 13331 continued An inoperable air lock door does not invalidate the previous successful performance of the overall air lock leakage test. This is reasonable since either air lock door is capable of providing a fission product barrier in the event of a DBA.
The results of the air lock leakage tests are evaluated against the acceptance criteria of the Containment h akage Rate Testing Program to ensure that the air lock leakage is properly accounted for in determining the combined Type B and Type C primary containment leakage.
The surveillance requirements for secondary containment leakage bypass paths ensure that these leakage rates are less then the specified leakage rate. This provides assurance that the assumptions in the radiological evaluations of the safety analysis are met. The leakage rate of each bypass leakage path is assumed to be the maximum pathway leakage (leakage through the worst of the two isolation valves) unless the penetration is isolated by use of one closed and de activated automatic valve, a closed manual valve, or a blind flange (or similar device). In this case, the leakage rate of the isolated bypass leakage path is assumed to be the actual pathway leakage through the isolation device. If both isolation valves in the penetration are closed, the actual leakage rate is the 1 esser leakage rate of the two valves. The surveillance testing frequency J
is stipulated by the Containment h akage Rate Testing Program.
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License Amendment Nos. 62 and 56 dated February 23, 1983 revised the i
Prairie Island Technical Specifications to conform to the requirements of Appendix J to 10 CFR Part 50.
That License Amendment approved several clarifications and exemptions to the Type B and C testing requirements of Appendix J to 10 CFR Part 50. Those clarifications and exemptions were incorporated into ths Prairie Island Technical Specifications in the form I
of Notes 1, 2 and 5 of Table TS.4.4-1.
Table TS.4.4 1 was subsequently relocated from the Prairie Island Technical Specifications in response to l
Ceneric latter 91-08, " Removal of Component Lists From Technical Specifications". While the reference of these notes to specific j
containment penetrations was relocated out of the Technical Specifications with Table TS.4.4-1, the specific clarifications and exemptions approved by License Amendment Nos. 62 and 56 are still binding. The applicability of the Type B and C testing clarifications and exemptions contained in Notes 1, 2 and 5 of relocated Table TS.4.4-1, to specific containment penetrations, is maintained in the Prairie Island Updated Safety Analysis Report.
The safety analysis (References 2, 3) is based on a conservatively chosen reference set of assumptions regarding the sequence of evants relating to activity release and attainment and maintenance of vacuum in the shield building annulus and the Auxiliary Building Special Ventilation Zone, the effectiveness of filtering, and the leak rate of the containment vessel as a function of time. The effects of variation in these assumptions, including that for leak rate, has been investigated thoroughly. A summary of the items of conservatism involved in the reference calculation and the magnitude of their effect upon off-site dose demonstrates the collective effectiveness of conservatism in these assumptions.
Prairie Island Unit 1 Amendment No. 497, 465, 126 Prairie Island Unit 2 Amendment No. 400, 408, 118 b
m t
i B.4.4 3 4.4 CONTAINMENT SYSTEM TESTS l
&aggg continued Several penetrations of the containment vessel and the shield building could, in the event of leakage past their isolation valves, result in leakage being conveyed across the annulus by the penetrations themselves, thus bypassing the function of the Shield Building Ventilation System (Reference 5).
Such leakage is estimated not to exceed.0256 per day.
A special zone of the auxiliary building has minimum leakage construc-
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tion and controlled access, and is designated as a special ventilation sons where such leakage would be collected by either of two redundant i
- r. rains of the Auxiliary Building Special Ventilation System. This system, when activated, will supplant the normal ventilation and draw a vacuum throu5 out the zone such that all outleakage will be throu5h particulate h
and charcoal filters which exhaust to the shield building exhaust stack.
)
The design basis loss-of-coolant accident was initially evaluated by the AEC staff (Reference 3) assuming primary containment leak rate of 0.5%
per day at the peak accident pressure. Another conservative assumption in the calculation is that primary containment leakage directly to the ABSVZ is 0.1% per day and leakage directly to the environs is 0.014 per day.
The resulting two-hour doses at the nearest SITE BOUNDARY and 30 day doses at the low population zone radius of 14 miles are less than guidelines presented in 10CFR100.
Initial leakage testing of the shield building and the ABSV resulted l
in a greater inleakage than the design basis. The staff has reevaluated doses for these higher inleakagc rates and found that for a l
primary containment leak rate of 0.256 per. day at peak accident pres-sure, the offsite doses are about the same as those initially calculated l
for higher primary containment leakage and lower secondary containment in-leakage (Reference 6).
The Residual Heat Removal Systems functionally become a part of the containment volume during the post-accident period when their operation is changed over from the injection phase to the recirculation phase.
Redundancy and independence of the systems permit a leaking system to be isolated from the containment during this period, and the possible conseyuences of leakage are minor relative to those of the Design Basis Accident (Reference 4); however, their partial role in containment warrants surveillance of their leak tightness.
The limiting leakage rates from the recirculation heat removal system are judgment values based primarily on assuring that the components could operate without mechanical failure for a period on the order of 200 days after a design basis accident. The test pressure, 350 psig, gives an adequate margin over the highest pressure within the system after a design basis accident. A recirculation heat removal system leakage of 2 gal /hr will limit off-site exposure due to leakage to insignificant levels relative to those calculated for leakage directly from the containment in the design basis accident.
i Prairie Island Unit 1 Amendment No. 94, 407, 615, 126 Prairie Island Unit 2 Amendment No. 84, 400, 498, 118
e d
B.4.4 4 4.4 CONTAINMENT SYSTEM TFSTS IA111 continued The Shield Building Ventilation System consists of two independent systems that have only a discharge point in common, the shield building vent.
both systems are normally activated and one alone must be capable of accomplishing the design function of the system. During the first operating cycle, tests were performed to demonstrate the capability of the separate and combined systems under different wind conditions.
During quarterly OPERABILITY tests, the drawdown transient of shield building pressure is compared to the computed predicted drawdown transient for non accident conditions and leakage equal to 75% of Figure TS.4.4 1 (840 cfm at -2.0 INWG). The -2.0 INWG setpoint of the recirculation damper must be reached and the equilibrium pressure in the annulus must be less than -1.82 INWG to demonstrate adequate shield building leak tightness.
Pressure drop across the combined HEPA filters and charcoal adsorbers of less than 6 inches of water at the system design flow rate will indicate that the filters and adsorbers are not clogged by excessive amounts of foreign mattsr. Pressure drop should be determined at i
least once per operating cycle to verify OPERABILITY.
The frequency of tests and sample analysis are necessary to show that the HEPA filters and charcoal adsorbers can perform as evaluated. A charcoal adsorber tray which can accommodate a sufficient number of representative adsorber sample modules for estimating the amount of l
penetration of the system adsorbent through its life is currently under development. When this tray is available, sample modules will be installed with the same batch characteristics as the system adsorbent and will be withdrawn for the methyl iodide removal efficiency tests.
Each module withdrawn will be replaced or blocked off. Until these i
trays can be installed, to guarantee a representative adsorbent sample, procedures should allow for the removal of a tray containing the oldest batch of adsorbent in each train, emptying of one bed from the tray, mixing the adsorbent thoroughly, and obtaining at least two samples.
One sample will be submitted for laboratory analysis and the other held as a backup.
If test results are unacceptable, all adsorbent in the train will be replaced. Adsorbent in the tray removed for sampling will be renewed. Any HEPA filters found defective will be replaced. Replacement charcoal adsorber and HEPA filters will be qualified in accordance with the intent of Regulatory Guide 1.52 Rev.
1 June 1976.
d 4
Prairie Island Unit 1 Amendment No. 94, 126 Prairie Island Unit 2 Amendment No. 84, 118
1 s
a B.4.4 5
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4.4 CONTAINKENT SYSTEM TESTS l
81111 continued If significant painting, fire, or chemical release occurs such that the HEPA filters or charcoal adsorbers could become contaminated from the fumes, chemicals, or foreign materini, the same tests and sample analysis will be performed as required for. operational use.
Operation of each train of the system for 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> every month will demonstrate OPERABILITY of the system and remove excessive moisture which may build up on the adsorber.
Periodic checking of the inlet heaters and associated controls for each train will provide assurance that the system has the capability of 1
reducing inlet air humidity so that charcoal adsorber efficiency is enhanced.
The in place test results should indicate a HEPA filter leakage of less than it through DOP testing and a charcoal adsorber leakage of less than 16 through halogenated hydrocarbon testing. The laboratory carbon sample test results should indicate a radioactive methyl iodide removal efficiency of at least 90% under test conditions which are more severe than accident conditions. The satisfactory completion of these periodic tests combined with the qualification testing conducted on new filters and adsorber provide a high level of assurance that the emergency air treatment systems will perform as predicted in the accident analyses.
In-place testing procedures will be established utilizing applicable sections of ANSI N510 - 1975 standard as a procedural guideline only.
A minimum containment shell temperature of 30*F has been specified to provide assurance that an adequate margin above NDTT exists. Evaluation of data collected during the first fuel cycle of Unit No. 1 shows that this limit can be approached only when the plant is in COLD SHUTDOWN.
Requiring containment shell temperature to be verified to be above 30*F prior to planc heatup from COLD SHUTDOWN provides assurance that this temperature is above NDTT prior to establishing conditions requiring CONTAINMENT INTEGRITY (Reference 7).
A maximum temperature differential between the average containment and annulus air temperatures of 44*F has been specified to provide assurance that offsite doses in the event of an accident remain below those cal-culated in the USAR. Evaluation of data collected during the first fuel cycle of Unit No.1 shows that this limit can be approached only when the plant is in COLD SHUTDOWN. Requiring this temperature differential to be verified to be less than 44*F prior to plant heatup from COLD SHUTDOWN provides assurance that this parameter is within accep-table limits prior to establishing conditions requiring CONTAINMENT j
INTEGRITY (Reference 7).
Reference.g 1.
USAR, Sec tion 5 and FSAR, Appendix 14-C 2.
USAR, Sec. tion 14 and FSAR, Appendix C 3.
Safety Evaluation Report, Sections 6.2 and 15.0 4.
USAR, Section 14 5.
USAR, Section 5.4.3 6.
Letter to NSP from AEC dated November 29, 1973 Prairie Island Unit 1 Amendment No. 94, 126 Prairie Island Unit 2 Amendment NO. 84, 118
l p"%,k UNITED STATES p+
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NUCLEAR REGULATORY COMMISSION o
8 WASHINGTON, D.C. 20ee64001
%4.....,&
NORTHERN STATES POWER COMPANY DOCKET NO. 50-306 PRAIRIE ISLAND NUCLEAR GENERATING PLANT. UNIT NO. 2 AMEN 0 MENT TO FACILITY OPERATING LICENSE Amendment No.118 License No. DPR-60 1.
The Nuclear Regulatory Comission (the Comission) has found that:
A.
The application for amendment by Northern States Power Company (the
]
licensee) dated October 25, 1996, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act),
and the Comission's rules and regulations set forth in 10 CFR Chapter I; B.
The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Comission; C.
There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations; D.
The issuance of this amendment will not be inimical to the comon defense and security or to the health and safety of the public; and E.
The issuance of this amendment is in accordance with 10 CFR Part 51 of the Comission's regulations and all applicable requirements have been satisfied.
2.
Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility Operating License No. DPR-60 is hereby amended to read as follows:
i I,
Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No.118, are hereby incorporated in the license.
The licensee shall operate the facility in accordance with the Technical Specifications.
3.
This license amendment is effective as of the date of issuance, with full implementation within 30 days.
FOR THE NUCLEAR REGULATORY C00911SSION h.
Beth A. Wetzel, Project Manager Project Directorate 111-1 Division of Reactor Projeu;s - III/IV Office of Nuclear Reactor Regulation
Attachment:
Changes to the Technical Specifications Date of Issuance: February 19, 1997 i
I 1
e
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ATTACHMENT TO LICENSE AMENDMENT NO.118 i
FACILITY OPERATING LICENSE NO. DPR-60 DOCKET NO. 50-306 Revise Appendix A Technical Specifications by removing the pages identified below and inserting the attached pages. The revised pages are identified by amendment number and contain vertical lines indicating the area of change.
REMOVE INSERT TS-viii TS-viii TS.4.4-1 TS.4.4-1 TS.4.4-2 TS.4.4-2 TS.4.4-3 TS.4.4-3 TS.4.4-4 TS.4.4-4 TS.4.4-5 TS.6.5-8 B.4.4-1 B.4.4-1 B.4.4-2 B.4.4-2 B.4.4-3 B.4.4-3 B.4.4-4 B.4.4-4 B.4.4-5 I
e TS viii TABLE OF CONTENTS (Continued)
TS_SECTION TITLE PAGE 6.0 ADMINISTRATIVE CONTROLS TS.6.1-1 6.1 Organization TS.6.1-1 6.2 Review and Audit TS.6.2-1 A. Safety Audit Committee (SAC)
TS.6.2-1
- 1. Membership TS.6.2-1
- 2. Qualifications TS.6.2-1
- 3. Meeting Frequency TS.6.2-2 j
- 4. Quorum TS.6.2-2
- 5. Responsibilities TS.6.2-2
- 6. Audit TS.6.2-3
- 7. Authority TS.6.2 4
- 8. Records TS.6.2-4
- 9. Procedures TS.6.2-4 B. Operations Committee (OC)
TS.6.2-5
- 1. Membership TS.6.2-5
- 2. Meeting Frequency TS.6.2 5
- 3. Quorum TS.6.2-5 j
- 4. Responsibilities TS.6.2-5
)
- 5. Authority TS.6.2-6
- 6. Records TS.6.2-6
- 7. Procedures TS.6.2-6 C. Maintenance Procedures TS.6.2-7 6.3 Special Inspections and Audits TS.6.3 1 6.4 Deleted 6.5 Plant Operating Procedures TS.6.5-1 A. Plant Operations TS.6.5-1 B. Radiological TS.6.5-1 j
C. Maintenance and Test TS.6.5 4 i
D. Delete l
E. Offsite Dose Calculation Manual (ODCM)
TS.6.5-4 F., Security TS. 6. 5 -5 C. Temporary Changes to Procedures TS.6.5 5 H. Radioactive Effluent Controls Program TS.6.5 6 I. Explosive Cas and Storage Tank Monitoring Program TS.6.5-7 J. Containment Leakage Rate Testing Program TS.6.5-8 l
6.6 Plant Operating Records TS.6.6 1 A. Records Retained for Five Years TS.6.6 1 B. Records Retained for the Life of the Plant TS.6.6-1 l
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Prairie Island Unit 1 - Amendment No. 422, 423, 126 Prairie Island Unit 2 - Amendment No. 445, 446, 118
TS.4.4-1 4.4 CONTAINMENT SYSTEM TESTS Anolicability Applies to integrity testing of the steel containments, shield buildings, auxiliary building special ventilation zone, and the associated systems including isolation valves and emergency ventilation systems.
Ohims11ve To assure that potential leakage from containment of either unit to the environs following a hypothetical loss of coolant accident in that unit is held within values assumed in the accident analysis.
Soecification A.
Containment Lankare Tests 1.
Perform required visual examinations and leakage rate testing in i
accordance with the Containment Leakage Rate Testing Program.
2.
Containment Airlock Leakage Tests Perform required containment air lock leakage testing in accordance with the Containment Laakage Rate Testing Program.
3.
Containment Isolation valve Leakage Tests Perform required containment isolation valve leakage testing in accordance with the Containment Leakage Rate Testing Program.
Prairie Island Unit 1 Amendment Nu. 62,126 Prairie Island Unit 2 Amendment No. 56,118
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TS.4.4-2 B.
Emeraency Charcoal Filter Systems 1.
Periodic tests of the Shield Building Ventilation System shall be performed monthly to demonstrate OPERABILITY, Each redundant train shall be initiated from the control room and determined to be OPERABLE at the time of its periodic test if it meets drawdown performance computed for the test conditions with 75% of the shield building in leakage specified in Figure TS 4.4-1 after initiation and achieve a pressure -2.0 inches of water gage.
2.
Periodic test of the Auxiliary Building Special Ventilation System shall be performed at approximately quarterly intervals to demonstrate its OPERABILITY. Each redundant train shall be initiated from the control room and determined to be OPERABLE at the time of periodic test if it isolates the normal ventilation system and produces a measurable negative pressure in the ABSVZ l
within 6 minutes after initiation.
3.
At least once per operating cycle, or once each 18 months, whichever comes first, tests of the filter units in the Shield Building Ventilation System and the Auxiliary Building Special Ventilation System shall be performed as indicated below; a.
The pressure drop across the combined HEPA filters and charcoal adsorbers shall be demonstrated to be less 6 inches of water at system design flow rate (1104).
b.
The inlet heaters and associated controls for each train shall be determined to be OPERABLE.
c.
Verify that each train of each ventilation system automatically starts on a simulated signal of safety injection and high radiation (Auxiliary Building Special Ventilation only).
4.
a.
The tests listed below shall be performed at least once per operating cycle, or once every 18 months whichever occurs first, or after every 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of system operation or following painting, fire or chemical release in any ventilation zone communicating with the system that could contaminate the I
HEPA filters or charcoal adsorbers.
(1)
In-place DOP and halogenated hydrocarbons test:s at design flows on HEPA filters and charcoal adsorbers banks respectively shall show k996 DOP removal for particles having a mean diameter of 0.7 microns and k994 halogenated hydrocarbons removal.
(2)
Laboratory carbon sample analysis shall show k90%
radioactive methyl iodide removal efficiency (130*C, 954 RH).
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l Prairie Island Unit 1 Amendment No. 62, 94, 126 Prairie Island Unit 2 Amendment No. 56, 84, 118
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l-TS.4.4-3 5
i b.
Cold DOP testing shall be performed after each complete or j
partial replacement of a HEPA filter bank or after any structural maintenance on the system housing that could j
affect the HEPA bank bypass leakage.
c.
Halogenated hydrocarbon testing shall be performed after i
each complete or partial replacement of a charcoal adsorber bank or after any structural maintenance on the system housing that could ai1=st the charcoal adsorber bank bypass leakage.
d.
Each circuit shall be operated with the heaters on at least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> every month.
5.
Perform an air distribution test on the HEPA filter bank after any maintenance or testing that could affect the air distribution within the systems. The test shall be performed at rated flow rate (ilot). The results of the test shall show the air distribution is uniform within i204.
C.
Containment vacuum Breakers The air-operated valve in each vent line shall be tested at quarterly intervals to demonstrate that a simulated containment vacuum of 0.5 psi will open the valve and a simulated accident signal will close the valve. The check valves as well as the butterfly valves will be leak-tested in accordance with the requirements of Specification 4.4.A.3.
D.
Residual Heat Removal System 1.
Those portions of the residual heat removal system external to the isolation valves at the containment, shall be hydrostatically tested for leakage during each refueling shutdown.
2.
Visual inspection shall be made for excessive leakage from components of the system. Any visual leakage that cannot be stopped at test conditions shall be measured by collection and weighing or by another equivalent method.
3.
The acceptance criterion is that maximum allowable leakage from either. train of the recirculation heat removal system components (which includes valve stems; flanges and pump seals) shall not exceed two gallons per hour when the' system is at 350 psig.
4.
Repairs shall be made as required to maintain leakage within the acceptance criterion in Specification 4.4.D 3 5.
If repairs are not completed within 7 days, the rest cer shall be shut down and depressurized until repairs are effecced and the acceptance criterion in 3. above is satisfied.
Prairie Island Unit 1 Amendment No. 62, 445, 126 Prairie Island Unit 2 Amendment No. 56, (98, 118
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l TS.4.4-4 E.
Containment Isolation Valves During each refueling shutdown, the containment isolation valves, shield building ventilation vaPass, and the auxiliary building normal ventilation system isolation valves shall be tested for operability by applying a simulated accident signal to them.
F.
Post Accident Containment Ventilation System During each refueling shutdown, the operability of system recirculating fans and valves, including actuation and indication, shall be demonstrated.
G.
Containment and Shield Buildina Air Temocrature Prior to establishing reactor conditions requiring containment integrity, the average air temperature difference between the containment and its associated Shield Building shall be verified to be within acceptable limits.
H.
Containment Shell Temeerature Prior to establishing reactor conditions requiring containment integrity, the temperature of the containment vessel wall shall be verified to be within acceptable limits.
I.
Electric Hydronen Recombiners Each hydrogen recombiner train shall be demonstrated Operable at least once each refueling interval by:
a.
Verifying during a recombiner system functional test that the minimum heater sheath temperature increases to greater than or equal to 700*F within 90 minutes. Upon reaching 700*F, increase the power setting to maximum power for 2 minutes and verify that the power meter reads greater than or equal to 60kw.
b.
Verifying through a visual examination that there is no evidence of abnormal conditions within the recombiner enclosures (i.e.,
loose wirin5 or structural connections, deposits of foreign materials, etc.), and c.
Verifying the integrity of all heater electrical circuits by performing a resistance to ground test. The resistance to ground for any heater phase shall be greater than or equal to 10,000 ohms.
Prairie Island Unit 1 Amendment No. 68, 116, 126 Prairie Island Unit 2 Amendment No. 62, $99, 118
- e TS.6.5 8 6.5.J. Containment Lankame Kate Testina Pronram 1
A program shall be established to implement the leakage rate testing of 1
the containment as required by 10 CFR 50.54(o) and 10 CFR 50, Appendix 1
J, Option B, as modified by approved exemptions. This program shall be in accordance with the guidelines contained in Regulatory Guide 1.163,
" Performance Based Containment Imak-Test Program," dated September 1995.
The peak calculated containment internal pressure for the design basis loss of coolant accident is less than the containment internal design pressure, P.,
of 46 psig.
The maximum allowable primary containment leakage rate, L.,
at P.,
shall be 0.25% of primary containment air weight por day. For pipes connected to systems that are in the auxiliary buildins special ventilation zone, the total leakage shall be less than 0.1% of primary containment air j
weight per day at pressure P.
For pipes connected to systems that are exterior to both the shield building and the auxiliary building special ventilation zone, the total leakage past isolation valves shall be less than 0.01% of primary containment air weight per day at pressure P,.
Laakage Rate acceptance criteria are:
a.
Primary containment leakage rate acceptance criterion is 5 1.0 L.
Prior to unit startup, following testing in accordance with the-program, the combined leakage rate acceptance criteria are 5 0.60 L, for all components subject to Type B and Type C tests and S 0.75 1, for Type A tests; b.
Air lock testing acceptance criteria are:
1)
Overall air lock leakage rate is 5 0.05 L, when tested at h46 psig 2)
For each door intergasket test, leakage rate is s 0.01 L, when pressurized to h10 psig.
The provisions of 4.0.A do not apply to the test frequencies specified in the Containment Laakage Rate Testing Program. The Containment Lankage Rate Testing Program stipulates acceptable extension of test intervals.
The provisions of 4.0.5 (except that the allowed surveillance intervals are defined by the Containment Leakage Rate Testing Program) are applicable to the Containment Lankage Rate Testing i
Program.
i Prairie Island Unit 1 Amendment No. 126 Prairie Island Unit 2 Amendment No. 118
4, 3.4.4-1 4.4 CONTAINMENT SYSTEM TESTS IAERE The Containment System consists of a steel containment vessel, a con-crete shield building, the Auxiliary Building Special Ventilation Zone (ABSVZ), a Shield Building Ventilation System, and an Auxiliary Building Special Ventilation System. In the event of a loss-of-coolant accident, a vacuum in the shield building annulus will cause most leakage from the containment vessel to be mixed in the annulus volume and recirculated through a filter system before its deferred release to the environment through the exhaust fan that maintains vacuum. Some of the leakage goes to the ABSVZ from which it is exhausted through a filter. A small fraction bypasses both filter systems.
The freestanding containment vessel is designed to accommodate the maximum internal pressure that would result from the Design Basis Acci-dent (Reference 1).
For initial conditions typical of normal operation, 120*F and 15 psia, an instantaneous double-ended break with minimum safeguards results in a peak pressure of less than 46 psig at 268'F.
The containment was initially leak-tested at 46.0 psig to meet acceptance specifications.
Maintaining the containment OPERABLE requires compliance with the visual examinations and leakage rate test requirements of theContainment Leakage Rate Testing Program. Failure to meet air lock leakage testing or secondary containment bypass leakage testing criteria does not necessarily result in a failure to satisfy this surveillance requirement.
The impact of the failure to meet any of these individual requirements must be evaluated against the Type A, B, and C acceptance criteria of the Containment Leakage Testing Program.
As left leakage prior to the first startup after performing a required leakage test is reqtt', red to be 5 0.6 L, for combined Type B and C leakage, and s 0.75 L, for overall Type A leakage. At all other times between required leakage rate tests, the acceptance criteria is based on an overall Type A leakage limit of 5 1.0 L. At 51.0 L, the offsite dose consequances are bounded by the safety analysis. The surveillance testing frequency is stipulated by the Containment leakage Rate Testing Program.
Maintaining containment air locks OPERABLE requires compliance with the leakage rate test requirements of the Containment Leakage Rate Testing Program. This surveillance requirement reflects the leakage rate testing requirements with respect to air lock leakage (Type B leakage tests). The acceptance criteria were established in the Safety Evaluation Report for License Amendment Nos. 62 and 56 dated February 23, 1983. The periodic testing requirements verify that the air lock leakage does not exceed the allowed fraction of the overall primary containment leakage rate. The surveillance testing frequency is stipulated by the Containment L4akage Rate Testing Program.
Prairie Island Unit 1 Amendment No. 94, 407, 126 Prairie Island Unit 2 Amendment No. 84, 409, 118
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B.4.4-2 4.4 CONTAINMENT SYSTEM TESTS Anana continued An inoperable air lock door does not invalidate the previous successful performance of the overall air lock leakage test. This is reasonable since either air lock door is capable of providing a fission product barrier in the event of a DBA.
t The results of the air lock leakage tests are evaluated against the acceptance criteria of the Containment Leakage Rate Testing Program to ensure that the air lock leakage is properly accounted for in determining the combined Type B and Type C primary containment leakage.
1 The surveillance requirements for secondary containment leakage bypass paths ensure that these leakage rates are less than the specified leakage rate. This provides assurance that the assumptions in the radiological evaluations of the safety analysis are met. The. leakage rate of each bypass l
leakage path is assumed to be the maximum pathway leakage (leakage through the worst of the two isolation valves) unless the penetration is l
isolated by use of one closed and de-activated automatic valve, a closed manual valve, or a blind flange (or similar device). In this case, the leakage rate of the isolated bypass leakage path is assumed to be the actual pathway leakage through the isolation device. If both isolation i
valves in the penetration are closed, the actual leakage rate is the 3
lesser leakage rate of the two valves. The surveillance testing frequency is stipulated by the Containment Leakage Rate Testing Program.
License Amendment Nos. 62 and 56 dated February 23, 1983 revised the 4
Prairia Island Technical Specifications to conform to the requirements of Appendix J to 10 CFR Part 50.
That License Amendment approved several clarifications and exemptions to the Type B and C testing requirements of Appendix J to 10 CFR Part 50.
Those clarifications and exemptions were incorporated into the Prairie Island Technical Specifications in the form of Notes 1, 2 and 5 of Table TS.4.4-1.
Table TS.4.4-1 was, subsequently relocated from the Prairie Island Technical Specifications in response to Generic Letter 91-08, " Removal of Component Lists From Technical Specifications". While the reference of these notes to specific containment penetrations was relocated out of the Technical Specifications with Table TS.4.4-1, the specific clarifications and exemptions approved by License Amendment Nos. 62 and 56 are still binding. The applicability of the Type B and C testing clarifications and exemptions contained in Noter 1, 2 and 5 of relocated Table TS.4.4-1, to specific containment penetrations, is maintained in the Prairie Island Updated Safety Analysis Report.
The safety analysis (References 2, 3) is based on a conservatively chosen reference set of assumptions regarding the sequence of events relating to activity release and attainment and maintenance of vacuum in the shield building annulus and the Auxiliary Building Special
)
Ventilation Zone, the effectiveness of filtering, and the leak rate of the containment vessel as a function of time. The effects of variation in these assumptions, including that for leak rate, has been investigated thoroughly. A summary of the items of conservatism involved in the reference calculation and the magnitude of their effect upon off-site dose demonstrates the collective effectiveness of conservatism in these assumptions.
Prairie Island Unit 1 Amendment No. 407, 445, 126 Prairie Island Unit 2 Amendment No. 400, 408, 118 1
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s B.4.4-3 4.4 CONTAINMENT SYSTEM TESTS AA11g continued Several penetrations of the containment vessel and the shield building could, in the event of leakage past their isolation valves, result in i
leakage being conveyed across the annulus by the penetrations themselves, j
thus bypassing the function of the Shield Building Ventilation System (Reference 5).
Such leakage is estimated not to exceed.0254 per day.
A special zone of the auxiliary building has minimum-leakage construc-tion and controlled access, and is designated as a special ventilation zone where such leakage would be collected by either of two redundant trains of the Auxiliary Building Special Ventilation System. This system, when activated, will supplant the normal ventilation and draw a vacuum throughout the zone such that all outleakage will be through particulate l
and charcoal filters which exhaust to the shield building exhaust stack.
l The design basis loss-of-coolant accident was initially evaluated by the AEC staff (Reference 3) assuming primary containment leak rate of 0.56 per day at the peak accident pressure. Another conservative assumption in I
I the calculation is that primary containment leakage directly to the ABSVZ is 0.1% per day and leakage directly to the environs is 0.01t per day.
i The resulting two hour doses at the nearest SITE BOUNDARY and 30-day doses l
at the low population zone radius of 14 miles are less than guidelines presented in 10CFR100.
i 1
Initial leakage testing of the shield building and the ABSV resulted in a greater inleakage than the design basis. The staff has reevaluated doses for these higher inleakage rates and found that for a primary containment leak rate of 0.256 per-day at peak accident pres-sure, the offsite doses are about the same as those initially calculated for higher primary containment leakage and lower secondary containment in leakage (Reference 6).
The Residual Heat Removal Systems functionally become a part of the containment volume during the post-accident period when their operation is Redy.,r9 over from the injection phase to the recirculation phase.dancy sui ind che f be isolated from the containment during this period, and the possible consequences of leakage are minor relative to those of the Design Basis Accident (Reference 4); however, their partial role in containment warrants surveillance of their leak tightness.
The limiting leakage rates from the recirculation heat removal system are judgment values based primarily on assuring that the components could operate without mechanical failure for a period on the order of 200 days after a design basis accident. The test pressure, 350 psig, gives an adequate margin over the highest pressure within the system after a design basis accident. A recirculation heat removal system leakage of 2 gal /hr will limit off-site exposure due to leakage to insignificant levels relative to those calculated for leakage directly from the containment in the design basis accident.
Prairie Island Unit 1 Amendment No. 94, 407, 165, 126 Prairie Island Unit 2 Amendment No. 84, 400, 408, 118
__.. _ _ _. __ _. _ _ _. _ _ _ _ ~._ _ __ _ _ _ _ _. _ _
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i B.4.4 4 4.4 CONTAINMENT SYSTEM TESTS j
AAAAA continued The Shield Building Ventilation System consists of two independent systems that have only a discharge point in common, the shield building vent.
Both systems are normally activated and one alone must be capable of accomplishing the design function of the system. During the j
first operating cycle, tests were performed to demonstrate the capability l
l of the separate and combined systems under different wind conditions.
During quarterly OPERABILITY tests, the drawdown transient of shield f
building pressure is compared to the computed predicted drawdown transient for non accident conditions and leakage equal to 75% of i
Figure TS.4.4-1 (840 cfm at -2.0 INWG). The -2.0 INWG setpoint of the recirculation damper must be reached and the equilibrium pressure in the annulus must be less than -1.82 INWG to demonstrate adequate shield j
building leak tightness.
Pressure drop across the combined HEPA filters and charcoal adsorbers of less than 6 inches of water at the system design flow rate will indicate that the filters and adsorbers are not clogged by excessive amounts of foreign matter. Pressure drop should be determined at i
least once per operating cycle to verify OPERABILITY.
The frequency of tests and sample analysis are necessary to show that the HEPA filters and charcoal adsorbers can perform as evaluated. A charcoal adsorber tray which can accommodate a sufficient number of representative adsorber sample modules for estimating the amount of l
penetration of the system adsorbent through its life is currently under development. When this tray is available, sample modules will be installed with the same batch characteristics as the system adsorbent and will be withdrawn for the methyl iodide removal efficiency tests.
Each module withdrawn will be replaced or blocked off. Until these trays can be installed, to guarantee a representative adsorbent sample, l
procedures should allow for the removal of a tray containing the oldest batch of adsorbent in each train, emptying of one bed from the tray, mixing the adsorbent thoroughly, and obtaining at least two samples.
r One sample will be submitted for laboratory analysis and the other held as a backup. If test results are unacceptable, all adsorbent in the train will be replaced. Adsorbent in the tray removed for sampling will be i
renewed. Any HEPA filters found defective will be replaced. Replacement charcoal adsorber and HEPA filters will be qualified in accordance wit,h the intent of Regulatory Guide 1.52 - Rev.
1 June 1976.
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Prairie Island Unit 1 Amendment No. 96, 126 Prairie Island Unit 2 Amendment No. 84, 118 l
a' B.4.4-5 4.4 CONTAINMENT SYSTEM TESTS 333g1 continued If significant painting, fire, or chemical release occurs such that the HEPA filters or charcoal adsorbers could become contaminated from the fumes, chemicals, or foreign material, the same tests and sample analysis will be performed as required for operational use.
Operation of each train of the system for 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> every month will demonstrate OPERABILITY of the system and remove excessive moisture which may build up on the adsorber.
Periodic checking of the inlet heaters and associated controls for each train will provide assurance that the system has the capability of reducing inlet air humidity so that charcoal adsorber efficiency is enhanced.
The in place test results should indicate a HEPA filter leakage of less than 14 through DOP testing and a charcoal adsorber leakage of less than it through halogenated hydrocarbon testing. The laboratory carbon sample test results should is,dicate a radioactive methyl iodide removal efficiency of at lea.* 904 under test conditions which are more severe than accident condition;. The satisfactory completion of u,ese periodic tests combined with the qualification testing conducted on new filters i
and adsorber provide a high level of assurance that the emergency air treatment systems will perform as predicted in the accident analyses.
In-place testing procedures will be established utilizing applicable sections of ANSI N510 - 1975 standard as a procedural guideline only.
A minimum containment shell temperature of 30*F has been specified to provide assurance that an adequate margin above NDTT exists. Evaluation of data collected during the first fuel cycle of Unit No. 1 shows that this limit can be approached only when the plant is in COLD SNUTDOWN.
Requiring containment shell temperature to be verified to be above 30*F prior to plant heatup from COLD SHUTDOWN provides assurance that this temperature is above NDTT prior to establishing conditions requiring CONTAINMENT INTEGRITY (Reference 7).
j A maximum temperature differential between the average containment and I
annulus air temperatures of 44*F has been specified to provide assurance that offsite doses in the event of an accident remain below those cal-culated in the USAR. Evaluation of data collected during the first fuel cycle of Unit No. I shows that this limit can be approached only when the plant is in COLD SHUTDOWN. Requiring this temperature differential to be verified to be less than 44*F prior to plant heatup from COLD SHUTDOWN provides assurance that this parameter is within accep-table limits prior to establishing conditions requiring CONTAINMENT INTEGRITY (Reference 7).
References 1.
USAR, Section 5 and FSAR, Appendix 14-C
.2.
USAR, Section 14 and FSAR, Appendix C 3.
Safety Evaluation Report, Sections 6.2 and 15.0 4.
USAR, Section 14 5.
USAR, Section 5.4.3 6.
Letter to NSP from AEC dated November 29, 1973 Prairie Island Unit 1 Amendment No. 96, 126 Prairie Island Unit 2 Amendment No. 84, 118 1