ML20072N936
| ML20072N936 | |
| Person / Time | |
|---|---|
| Site: | Fort Calhoun  |
| Issue date: | 07/07/1983 |
| From: | William Jones OMAHA PUBLIC POWER DISTRICT |
| To: | Clark R Office of Nuclear Reactor Regulation |
| References | |
| LIC-83-161, NUDOCS 8307180182 | |
| Download: ML20072N936 (16) | |
Text
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Omaha Public Power District 1623 Harney Omaha, Nebraska 68102 402/536-4000 July 7, 1983 L IC-83-161 Mr. Robert A. Clark, Chief U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Division of Licensing Operation Reactors Branch No. 3 Washington, D.C.
20555
Reference:
Docket No. 50-285
Subject:
Relief Requests from ASME Boiler and Pressure Vessel Code,Section XI
Dear Mr. Clark:
Pursuant to 10CFR50.55a(g)(5)(iii), Omaha Public Power District is forward-ing for approval the attached relief requests for the Fort Calhoun Sta-tion. The District has completed a review of the criteria of the Winter 1980 Addenda to the ASME Boiler and Pressure Vessel Code (the Code) and has detemined that certain requirements are impractical for the Fort Calhoun Station. The attachment identifies those code requirements (eter-mined to be impractical and provides infomation to support this detenntn-ation.
Please note the District is still developing the new ten-year Inservice Inspection (ISI) program that will become effective September 26, 1983.
As development continues, additional code requirements may be detemined to be impractical; however, the District is confident that the attached listing represents the full set of exceptions that are of a short tem re-curring nature. Thus, approval of the attached relief request will ensure District compliance with 10CFR50.55a(g) as a minimum to the start of the 1984 refueling outage. Additional relief requests, if identified, will be submitted with the new ten year ISI program to be submitted by September 26, 1983.
The majority of these exemption requests were previously approved under the District's current ten-year ISI program. Those requests which differ from the requests previously granted are denoted by an asterisk. The changes to the Class 1 Examination Exceptions are due to minor code 8307180182 830707 m114 PDR ADOCK 05000285 VT5 G
PDR G5 5124 Employmen h
al opportumty l
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Mr. Robert A. Clark July 7, 1983 Page Two changes. Tnus far, no additions to the District's previous inservice test-ing of valves exception requests (provided in the District's letter dated December 1,1982) have been identified.
Sincerely,
a f Hk A W. C. Jones Division Manager Production Operations WCJ/TLP/rh Attachment cc:
LeBoeuf, Lamb, Leiby & MacRae 1333 New Hampshire Avenue, N.W.
Washington, D.C.
20555 Mr. L. A. Yandell Senior Resident Inspector
.I
Exceptions to Compliance with the Examination Requirements of the Winter 1980 Addenda to the ASME Boiler and Pressure Vessel Code, Section 'XI, Rules for Inspection of Nuclear Power Plant Components Exceptions, Class 1 Examinations Item No.
- B1.40 The closure head-to-flange weld is inaccessible for examina-tion due to interference from the seismic skirt. Visual examination for leakage shall be perfonned in accordance with IWB-5221 and IWB-5222.
B3.10 The reactor vessel nozzle-to-vessel welds cannot be 100% volum-etrically examined from the outside due to interference from nozzle supports. These welds will be examined to 100% of the volume from inside of the vessel near the end of the inspec-tion interval.
B3.20 The reactor vessel inside radius section cannot be 1005 volume-trically examined from the outside due to interference from nozzle supports. This area will be examined to 100% of the volume from the inside of the vessel near the end of the inspection interval.
B3.30 The pressurizer surge line nozzle-to-shell weld cannot be 100%
volumetrically examined due to interference from heater pene-trations. The weld will be volumetrically examined to the extent possible. The weld area will be visually examined for leakage near the end of the inspection interval in accordance with IWB-5221 and IWB-5222.
B3.40 The pressurizer surge line inside radius section cannot be 100% volumetrically examined due to interference from heater penetrations. The area will be volumetrically examined to the extent possible. The area will be visually examined for leak-age near the end of the inspection interval in accordance with IWB-5221 and IWB-5222.
B6.20 &
B6.30 Closure head studs will be ultrasonically examined from the center drilled hole in accordance with ASME Code Case N-307 as referenced in Regulatory Guide 1.147, Inspection Code Case Acceptabili ty.
B12.10 The District is evaluating the feasibility in tenns of eco--
nomics, radiation exposure, and experiences at other PWR facil-ities in the volumetric examination of reactor coolant pump casing welds. The District may request exemption from this testing requirement at a later date.
B12.20 A visual examination of the RC pump casing internal surfaces will be performed only if the pump is disassembled for volum-etric examination, or maintenance such that internal surfaces 1
Exc ptions, Class 1 Examinations B12.20 (Continued) became accessible.
Examination during the leakage and hydro testing of IWB-5221 and IWB-5222 during the first-10 year inspection interval revealed no leakage from the pump casing.
This test will be repeated near the end of the second inspection interval and is judged to be adequate based upon design, fabrication, and accessibility considerations.
B15.50 &
B15.51 The following are inaccessible piping welds:
Figure No.*
Line No.
Weld No.
A-22 12 In. - SI-12 16 A-25 12 In. - SI-24 16 A-27 6 In. - SI-14 10 A-27 6 In. - SI-14 11 A-32 3 In. - HPH-22 1
A-32 3 In. - HPH-22 3
A-38 2 In. - HPH-2.12 5
A-42 12 In. - SDC-20 7
The welds listed above are inaccessible for examination because they are located within walls or floor 3.
Areas on either side of the walls or floors containing these piping welds v;11 Le excained for signs of leakage during the pressure and hydrostatic testing of the piping systems in accordance with IWB-5221 and IWB-5222.
- See the 10-Year Inservice Examination Plan, Fort Calhoun Nuclear Station Unit No.1, dated October 1978.
Exceptions, Class 2 Exaninations C5.20 The following are inaccessible piping welds:
Figure No.*
Line No.
Weld No.
B-12 12 In-LPSI-12 4
B-13 12 In-LPSI-14 7
B-13 12 In-LPSI-14 10 B-13 12 In-LPSI-14 11 B-14 12 In-LPSI-22 10 B-15 12 In-LPSI-24 4
The welds listed above are inaccessible for examination because they are located within walls or floors. Areas on either side of the walls or floors containing these piping welds will be examined for signs of leakage during the pressure and hydrostatic testing of the piping systems in accordance with IWB-5221 and IWB-5222.
l
- See the 10-Year Inservice Examination Plan, Fort Calhoun l
Nuclear Station Unit No.1, dated October 1978.
I 2
Exctptiens, Class 3 Examinations D2.10
-Inaccessible Piping:
Buried raw water lines from the intake structure to the auxil-iary building cannot be tested since the isolation valves are not designed to be leak-tight shut-off valves. Flow instrumen-tation in the system is capable of detecting significant leaks 4
by sensing a reduction of flow.
Exception, Article IWF-5000 Snubbers:
4 The. District has in effect, surveillance procedures meeting the require-ments of our Technical Specification 3.14, Shock Suppressors, and will continue to follow these requirements in exception to the ASME Section XI requirements of Article IWF-5000.
Exceptions to the Inservice Testing of Pumps,- Article IWP-3000
{
General:
All the pumps subject to testing are directly coupled to induction motor drivers; therefore, the rotation speed need not be measured as prescribed in Subarticle 4400.
Low Pressure Safety Injection Pumps SI-1A, B Class 2 Function:
The LPSI pumps are available for safety injection of borated water into the reactor coolant system following a LOCA and are used to remove residual heat for cold shu tdowns.
4
' Containment Spray Pumps SI-3A, B, C Class 2 Function:
The CS pumps are available to spray borated water into 4
1 l-.
containment following a LOCA.
High Pressure Safety Injection Pumps SI-2A, B, C Class 2 Function:
The HPSI pumps are available for safety injection of borated water into the reactor coolant system following a LOCA and are used.to maintain the required water level
'in the safety. injection' tanks. -
Exceptions:
IWP-3000 Inlet.and differential pressure measurement Basis:
Inlet pressure for these tests will be determined by" measuring the ~ static head. tank ; level.
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Exct.ptions to tha Inservice Testing of Pumps, Article IWP-3000 Component Cooling Pumps AC-3A, B, C Class 3 Function:
The component cooling pumps supply cooling water to equipment in the containment and auxiliary building.
Exceptions:
IWP-3110 Establishment of a reference value for flow rate.
Basis: There are many components or subsystems on the component cooling water system with several possible piping configurations.
Some of the components are crit-ical elements to which the flow rate cannot arbitrarily be varied for the sake of running a pump test.
Refer-ence values are established instead using pump curves and previous data. Consequently, establishing a refer-ence flow rate for a pump test on a periodic basis is impractical.
IWP-3110 Lubricant level or pressure observation.
Basis: The pump bearings are cartridge type that have been re-packed with the proper amount of grease and under normal conditions req"sre no further attention for the life of the bearings.
Raw Water Pumps AC-10A, B, C, D Class 3 Function:
The raw water pumps provide a cooling medium for the com-ponent cooling water system.
Exceptions:
IWP-3100 Inlet pressure measurement Basis: System design does not permit direct measurement of inlet pressure. Varying river level and unknown accumulations of sand near the pump suction bell makes it impossible to detemine the inlet pressure.
IWP-3100 Differential pressure measurement.
Basis: Because of the inability to measure inlet pres-sure, differential pressure measurement is not possible.
In lieu of a differential pressure measurement, a dis-
. charge pressure vs. motor anperage measurement will be taken. An acceptable motor amperage value will be deter-mined over a discharge pressure range of 26 psig to 40 psig.
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Exceptions to the Inservice Testing of Pumps, Article IWP-3000 Raw Water Pumps AC-10A, B, C, D Class 3 (Continued)
IWP-3100 Flow rate measurement.
Basis: The system design does not provide an accurate indication of flow rate due to fouling by untreated river water.
IWP-3100 Bearing temperature measurement.
Basis: All bearings are inaccessible for temperature measurement. All are submerged in river water.
Exception to IWP-3220 for All Pump Tests:
All test data shall be analyzed within 4 working days after completion of a test.
Basis: An allowance of 4 working days to analyze test data instead of the 96 hour0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> requirement will allow greater flexibility in scheduling and perfonning the various tests.
Special allowances for weekends and holidays will not have to be made in scheduling the tests. The safety related consequences of completing analysis within 4 working days rather than 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> is not considered to be great, since pump tests are per-formed on a quarterly basis.
Exceptions to the Inservice Testing of Valves, Article IWV-3000 IWV-3420 Leak Rate Testing:
The following Category A valves are listed in groups repre-senting those valves which must be tested simultaneously due to system configuration.
1.
TCV-202, HCV-204 2.
HCV-241, HCV-206 3.
HCV-506A, HCV-506B 4.
HCV-467C, HCV-467D 5.
HCV-507A, HCV-507B 6.
HCV-467A, HCV-467B
~
7.
HCV-438C, HCV-438D 8.
HCV-438A, HCV-438B 9.
HCV-500A, HCV-500B 10.
HCV-2983, SI-185, HCV-2956, HCV-2976, HCV-2936, i
HCV-2916, PCV-2949, HCV-2969, PCV-2909, PCV-2929 11.
HCV-509A, HCV-509B l
12.
HCV-508A, HCV-508B 1
I
Exc:ptions to tha Inservice Testing of Valves, Article IWV-3000 IWV-3420 Leak Rate Testing:
(Continued) 13.
HCV-882, VA-289
]
14.
HCV-425A, HCV-425B 15.
HCV-425C, HCV-425D 16.
HCV-2603A, HCV-2603B 17.
HCV-2604A, HCV-2604B 18.
HCV-2504A, HCV-2504B 19.
PCV-742E, PCV-742F 20.
PCV-742G, PCV-742H 21.
HCV-746A, HCV-746B 22.
HCV-881, VA-280 23.
HCV-1560A, HCV-1560B 24.
HCV-1559A, HCV-1559B 25.
PCV-742A, PCV-7428 26.
PCV-742C, PCV-7420 IWV-3412 Inservice testing at cold shutdown:
Valve testing should commence not later than 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> after shutdown and continue until complete or plant is ready to return to power.
Cocpletion of all valve testing is not a pre-requisite to return to power. Any testing not completed at one cold shutdown should be performed during subsequent cold shutdown to meet the code required testing frequency.
The following are the Category A, B, and C valves for which exceptions to the Inservice testing requirements are being requested:
Category A Valves:
HCV-241 This valve is used for reactor coolant pump controlled bleed-off isolation.
It cannot be stroked when the reac-tor coolant system is pressurized, because controlled bleed-off flow must be maintained to prevent damage to the reactor coolant pump seals. The valve cannot be partial-stroked because it is either fully open or fully closed.
HCV-206 This valve serves as penetration M-7 isolation. This valve cannot be stroked when the reactor coolant system is pressurized because controlled bleed-off flow must be main-tained to prevent damage to the reactor coolant pump seal s.
The valve cannot be partially-stroked because it is either fully open or fully clo' sed.
TCV-202 This valve is used for RCS loop 2A, letdown isolation and temperature regulation.
Stroking of this valve quarterly during operation or at cold shutdowns would result in the termination of the charging and letdown flows. This would aisc isolate the boronometer, process radiation monitor, and reactor coolant system purification process and would l
6
l Exc ptions to tha Inservice Testing of Valvss, Article IWV-3000 -
Category A Valves: (Continued)
TCV-202 (Continued) have the potential of causing a reactivity excursion.
This valve cannot be partial-stroked because it is either l
fully open or fully closed.
HCV-204 The function of this valve is for containment penetration M-2, isolation and letdown control. The stroking of this valve quarterly during operation or at cold shutdowns would result in termination of the charging and letdown flows.
This would also isolate the Laronometer, process radiation monitor, and reactor coolant system purifcation process.
In addition, the potential would exist for a reactivity excursion. This valve cannot be partial-stroked because it is either fully open or fully closed.
SI-185 This valve is used to isolate the fill line for safety injection tanks.
It has been designated as Category A/E.
The valve is locked closed, and therefore is not subject to a stroke test. The valve will be leak-tested in accordance with Category A leak testing requirements.
HCV-2916 The function of these valves is to permit filling and drain
- 2936, ing of safety injection tanks. These valves cannot be
- 2956, stroked during operation because doing so would cause level 2976 fluctuations in the safety injection tanks. The level of the safety injection tanks is controlled by Technical Spec-ifications, and stroking the valves may result in a viola-tion of these Technical Specifications.
PCV-742A These valves are used for containment purge air isolation 742B and are closed during normal operations and cold shutdowns.
742C They are in the position required to fulfill their design 742D functions and when open could provide a direct path for release of contaminants from containment. Therefore, stroking these valves may result in a potential release of contaminants.
In addition, valves PCV-742A and 742C cannot be tested in the direction of their design function in accordance with IWV-3420 due to system configuration.
The intent of subsection IWV of the Section XI code, to verify operational readiness is met since testing in the direction opposite to the design function will result in a greater leakage than would be experienced in a test in the preferred direction.
HCV-881 The function of these valves is to isolate containment 882 hydrogen purge. Stroking at cold shutdown or quarterly intervals is not advisable, since doing so would provide a direct path for release of contaminants from the containment.
7
Exceptions to the Inservice Testing of Valves, Article !WV-3000 Category A Valves: (Continued)
VA-280 The valves serve to isolate contaiment hydrogen purge and 289 are designated as Category A/E. They meet Category E criteria because they are locked closed. Cycling of these valves would provide a direct path for release of contaminants from the contaiment during power operation or cold shutdown.
HCV-1559A The valves serve to isolate the containment domineralized 1559B water line at M-80.
Cycling these valves would decrease containment integrity.
In addition, these valves are r.ot required to be opened during power operation.
HCV-1560A These valves function to isolate the fill and makeup demin-1560B eralized water lines to the pressurizer quench tank at pene-tration M-79.
Cycling of these valves would decrease con-tainment integrity. These valves are not required to be opened during power operation.
HCV-2504A This valve serves to isolate the containment reactor coolant system sample line at penetration M-45.
This valve cannot be leak-tested in the direction of its design function in accordance with IWV-3420 due to systen configuration. The intent of subsection IWV of the Section XI code, to verify operational readiness is met since testing in the direction opposite to the design function will result in a greater leakage than would be experienced in a test in the preferred direction.
HCV-1749 This valve serves to isolate contaiment penetration M-74, compressed air penetration. This valve cannot be leak-tested in the direction of its design function in accordance with IWV-3420 due to system configuration. The intent of subsection IWV of the Section XI code, to verify the operational readiness, is met since testing in the direction opposite to the design function will result in a greater leakage than would be experienced in a test in the preferred direction.
HCV-425A These valves serve to isolate containment penetrations M-39 425B and M-53, component cooling system penetrations.
Stroking 425C cannot be performed during cold shutdown or at quarterly 4250-intervals because failure of these valves in the closed position would terminate cooling to safety injection tanks leakage coolers which would in turn have potential for resulting in hot fluid streams entering ion exchange resins of chemical volume control system, thereby causing damage. These valves cannot be partial-stroked because they are either fully opened or fully closed.
8
Exceptions to the Inservice Testing of Valvas, Article IWV-3000 Category A Valves: (Continued)
HCV-438A These valves serve to isolate containment penetrations M-18, 438B and M-19, component cooling system penetrations.
Stroke-438C testing cannot be perfomed at quarterly intervals or cold 4380 shutdown because one or more reactor coolant pumps are in operation at all times and these pumps require lube oil and seal cooling. Stroking of these valves would tenninate lube oil and seal cooling. These valves cannot be partial-stroked because they are either fully opened or fully closed.
HCV-467A These valves serve to isolate containment penetrations M-15, 467B and M-11, component cooling system penetrations. These 467C valves cannot be stroked quarterly because failure of the 467D valve during testing would render the nuclear detector well cooling units inoperable. Should the nuclear detector well cooling units fail, Technical Specification 2.13 could not Le met. The valves cannot be partial-stroked because they are either fully opened or fully closed.
HCV-2603B Contaiment isolation to penetrations M-42 and M-43, nitro-HCV-2604B gen gas header penetrations. These valves cannot be leak-tested in the direction of their design function in accor-dance with IWV-3420 due to system configuration. The intent of subsection IWY of the Section XI code, to verify the operational readiness, is met since testing in the direction opposite to the design function will result in a greater leakage than would be experienced in a test in the preferred direction.
PCV-1849 This valve serves to isolate instrument air pressure (via penetration M-7) to contaiment systens.
Stroke-tes ting cannot be performed at cold shutdown or quarterly since instrument air must be available at all times during operation and cold shutdown. The valve cannot be partial-stroked because it is either fully open or fully cl osed.
Category B Valves:
LCV-101-1 These valves serve to maintain pressurizer level control.
101-2 Stroke-testing cannot be performed during cold shutdown or quarterly because doing so would disrupt pressurizer level regulation capabilities. Upsetting pressurizer level regulation could result in RCS overpressurization. These valves cannot be partial-stroked during operation for the same reason.
LCV-218-2 This valve functions to provide volume control tank level control. The valve cannot be stroke-tested in either cold shutdown or quarterly because doing so would tenninate 9
Exceptions to th2 Insarvice Testing of Valves, Article IWV-3000 Category B Yalves: (Continued)
LCV-218-2 (Continued) charging flow to the reactor coolant system and would have the potential for disrupting pressurizer level regulation.
Pressurizer level regulation disruption can lead to reactor' coolant system overpressure transients.
Partial stroke-testing cannot be performed because the valve is either fully closed or fully opened.
HCV-240 Cycling this valve during operation would cause excess pressurizer spray, causing a reactivity excursion (see LCV-101-1,2).
HCV-258 These valves serve to isolate concentration boric acid from 265 the charging pump suction header. These valves cannot be cycled during cold shutdown or quarterly because doing so would cause concentrated boric acid to be injected into the reactor coolant systen via charging pump suction header gravity feedline. Boration of the primary system during normal operation would cause reactivity transients and possibly shut down the plant and during cold shutdowns would delay startup. These valves cannot be partial-stroked for the same reason.
HCV-268 This valve serves to pennit direct feed of concentrated boric acid solution to the charging pump suction header.
This valve cannot be stroke-tested during cold shutdown or quarterly because doing so would align concentrated boric acid storage to the charging pump suction header through the boric acid pumps. Boration of the primary system during normal operation would cause reactivity transients and possibly shut down the plant and during cold shutdowns would delay startup. The valve cannot be partial-stroked for the same reason.
HCV-344 These valves serve as containment spray isolation. Stroke-345 testing during cold shutdown or quarterly is not advisable since the potential for spraying down the containment is increased. These valves represent the only boundary between the safety injection pump header and containment spray nozzles. The valves cannot be partial-stroked for the same reason.
HCV-347 These valves serve to isolate the shutdown cooling line.
348 They cannot be stroked quarterly because the operation of these valves is inhibited by dual pressure -interlocks when the reactor coolant system pressure is greater than 265 psia.
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Excsptions to the Instrvice Testing of-Valvas, Article IWV-3000 Category B Yalves: (Continued) i.
HCV-400A,B,C & D These valves serve to isolate component cooling to contain-l
.401A,B,C & D ment air cooling and filtering units. They cannot be cycled j
402A,B,C & D quarterly because doing so would tenninate component cooling 403A,B,C & D to air cooling and filtering units in containment.
HCV-1041A These valves serve to isolate the main steam headers. They 1042A cannot be tested quarterly during operation because doing i
so would isolate steam flow in the steam generators and result in a turbine and reactor trip. The valves cannot be partial-stroked because they are either fully opened or fully closed.
HCV-1041C These valves serve to provide a pathway from the stean gen-1042C erators to steam dump and by-pass valves in the event that the main steam isolation valves close. These valves are also used to pre-heat the turbine and related steam system during startup. Cycling of these-valves on a quarterly basis during operation would cause the main steam isola-j tion valves to close, causing the turbine to trip and j
resulting in a reactor trip. The valve cannot be partial-i stroked for the same reason.
i HCV-1387A These valves serve to isolate steam generator blowdown.
1387B They cannot be stroke-tested quarterly during operation 1388A because doing so would terminate steam generator blowdown 13888 and disrupt all-volatile chemistry control. They cannot be partial-stroked because they are fully opened or fully closed.
HCV-1385 These valves serve to isolate main feedwater to the steam i
1386 generators. Quarterly stroke-testing cannot be performed during operation because doing so would isolate feedwater to steam generators resulting in a reactor trip. These valves cannot be partial-stroked because they are either j
fully opened or fully closed.
HCV-2506A These valves serve as containment isolation valves to isol-2506B ate steam generator blowdown sampling lines. Stroke-testing
)
2507A cannot perfomed quarterly during operation because doing so l
2507B would terminate blowdown sample line flow. The steam genera-tor blowdown activity monitor is on the sample line. Tech-nical Specification 2.9(1)d requires that blowdown activ-ity shall be continuously monitored by the steam generator blowdown sample monitoring. system. Partial-stroking can-not be perfomed since these valves are either fully
-opened or fully closed.
Category C Valves:
CH-198~
This valve functions to prevent back-flow to the charging pump discharge header..The. valve is normally open and.
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Exc;ptions to the Inscrvice Testing of Valves, Article IWY-3000 Category C Valves: (Continued)
CH-198 (Continued)
I there is no way that back-seating can be tested on reversal of flow.due to system piping arrangements.
Partial stroke-testing cannot be performed for the same reason.
SI-159 These valves function to prevent back-flow to the contain-160 ment lower level. These valves are normally closed and are backed up by motor operated isolation valves HCV-383-4 and HCV-383-3, which are normally closed, fail-as-is, and are opened only on receipt of a containment recirculation actuation signal.
No feasible means exists in the system to perform an in place operational test of either SI-159 or SI-160.
In lieu of the required testing frequency of every 3 months, the District will remove and inspect, on an alternating five year schedule, each of these valves. The inspection will involve photographic documentation of valve internal condi tion. The inspection will include an evaluation of valve components for wear, defects or failures, accumula-tion of deposits, and freedom of movement.
Previous exam-ination of SI-159, as reported in our letter to R. A.
Clark of the Caumission on July 9,1980, and of SI-160 as reported to R. A. Clark of the Commission on Nov. 20, 1981, revealed the valves to be in like-new condition and fully operational. The District has no reason to believe that this excellent condition will not be maintained.
Considaring that these valves are redundant to one another in providing a flow path to the SI pumps upon start of the recirculation mode of operation of this safety system, con-sidering that each valve has two independent halves, and since the failure of either half to open would not impede required flow rates, the District believes that the pro-posed examination schedule is more than adequate to insure proper valve reliability and hence, system availability.
SI-139 These valves function to prevent back-flow to the safety 140 injection and refueling water tank.
They will be part-stroked exercised every three months and full-stroked exercised at refueling outages. Full-stroke testing cannot be performed during cold shutdown or quarterly during operation because doing so would require safety injection to the containment or reactor coolant system. A safety injection to the reactor coolant system during operation would cause uncontrolled boration and would introduce a thermal shock to the system. The recircu-lation lines that are used for testing the LPSI and HPSI pumps for partial-stroking are not large enough to fully open the check valves.
l 12
Exceptions to the Inservice Testing of Valves, Article IWV-3000 i
I Category C Valves: (Continued) i SI-102 These valves function to prevent back-flow to high pressure
- 1 108 and low pressure safety injection pumps and containnent 115 spray pumps. They cannot be tested during operation 121 quarterly or at cold shutdowns because doing so would 129 disrupt safeguard system alignment, and safety injection 135 into the containment or the reactor system would be required 143 for valve testing. Partial stroking cannot be performed for l
149 the same reasons.
SI-100 These valves serve to prevent back-flow from high pressure 113 headers to main safety injection headers. They cannot be fully tested during operation quarterly or during cold shutdowns since to do so would require a safety injection to the reactor coolant system. Partialstroking quarterly is possible since these pumps can be placed in a minimum recirculation mode of operation.
4 SI-207 These valves function to isolate reactor coolant system 211 leakage flow from the safety injection tanks. These valves 215 cannot be stroke-tested during cold shutdown or quarterly 219 during operation to do so would cause drainage of the safety injection tanks. Technical Specifications require safety injection tank levels to be maintained. The valves cannot be partial-stroked for the same reason.
SI-208 These valves function to prevent back-flow from the reactor 212 coolant system through the safety injection system. These 216 valves cannot be tested during cold shutdowns or quarterly 220 during operation because to do so would introduce cold charging water to the reactor coolant system causing thermal i
shock. The valves cannot be partial-stroked for the same reasons noted above.
SI-194 These valves function to prevent back-flow through the safety 195 injection pump discharge headers. These valves cannot be 196 stroke-tested during cold shutdowns or quarterly during oper-197 ation because to do so using the safety injection systen 198 would require introducing cold water into the reactor coolant 199 system causing a thermal transient and possibly a reactor ex-200 cursion. To do so using the chemical volume control system 201 would disrupt charging and letdown flow to the reactor coolant 202.
system causing _ chemical and volume control to the system to be 203 di srupted.
204 205 SI-175 These valves serve to prevent back-flow from the contain-176 ment spray headers. These valves cannot be tested to the open position since to do so-could cause spray in contain-
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Exetptiens to the Inservice Testing of Yalves, Article IWV-3000 Category C Valves: (Continued)
SI-175 (Continued) 176 ment. Not stroking the valves poses no safety impact for the following reasons:
1.
Adequate heat removal from containment can be achived during a DBA by use of only one containment spray header with three containment spray pumps. Hence, only one of the check valves is required to open.
2.
The containment air filtration and cooling system is fully redundant to the containment spray system.
3.
The containment air filtration and cooling system contains redundant components. During a DBA, sufficient iodine removal is achieved with 50% of the system operating and sufficient pressure reduction accomplished with any three air coolers operating.
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