ML18051A773
| ML18051A773 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 01/26/1984 |
| From: | Crutchfield D Office of Nuclear Reactor Regulation |
| To: | Vandewalle D CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| References | |
| LSO5-84-01-045, LSO5-84-1-45, NUDOCS 8401300156 | |
| Download: ML18051A773 (11) | |
Text
Docket No. 50-255 LS05-84-01-045 Mr. David J. VandeWalle Nuclear Licensing Administrator Consumers Power Company 1945 West Parnall Road Jackson, Michigan 49201
Dear Mr. VandeWalle:
January 26, 1984
SUBJECT:
CONTAINMENT PURGING AND VENTING Re:
Palisades Plant Your letter dated August 24, 1982 indicated that Consumers Power Company is working on an evaluation to justify unlimited use of the modified containment vent and purge system at the Palisades Plant.
You indicated that the antici-pated completion for this study was December 31, 1982.
To date we have not received this evaluation for review.
We request that you provide a schedule for the submittal of this evaluation for NRC staff review and approval within 30 days of the receipt of this letter. Because your modified system is not described in the Palisades FSAR, your submittal should include a description and P&ID's for this system.
Pending our review of your evaluation, operation of the modified containment vent and purge system should meet the NRC staff 1s interim position for containment purge and vent valve operation as specified in our letter dated October 23, 1979 (for convenience provided as Enclosure 1 to this letter).
Please provide a response within 30 days of the receipt of this letter indicating how you are meeting this. interim position.
The NRC Project Manager will arrange a conference call with members of your staff to discuss this matter.
The above issues should be resolved prior to the restart from the current outage.
I am also providing the following for your guidance:
- 1.
"Clarification of Valve Usage 11 (Enclosure 2). This is a restatement of the salient features of Branch Technical Position CSB 6-4 indicating to assist you in understanding the staff's position relating to the use of containment purg~/vent valves.
*~
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Mr. David January 26, 1984
- 2.
"Purge/Vent Valve Leakage Tests" (Enclosure 3).
- 3.
Sample Technical Specifications (Enclosure 4) are provided for your consideration.
We request that you review existing Technical Specifications against the sample provided herein.
For any areas in which your existing Technical Specifications needs expansion, you are requested to provide a Technical Specification change within 60 days of receipt of this letter.
Finally, the information identified in Enclosure 5 is needed to evaluate the conformance of the Palisades Plant to the guidelines of.Branch Technical Position CSB 6-4 Revision 1, "Containment Purging During Normal Operation.
11 Please provide a response to the information requested in Enclosure 4 within 45 days of the receipt of this letter.
The reporting and/or recordkeeping requirements contained in this letter affect fewer than ten respondents; therefore, OMB clearance is not required under P.L.96-511.
Enclosures:
As stated cc w/enclosures:
See next page DISTRIBUTION Docket File NRC PDR Local PDR NSIC ORB #5 Reading DCrutchfield HSmith vJPaul son DELO ELJordan JMTayl or ACRS (10)
DLi:)\\~ #5 vJP~~}son: cc I ~/84 EReeves DL: ORB df!vf ERee~/L----
/)jJ84 Sincerely, Original signed by Dennis M. Crutchfield, Chief Operating Reactors Branch #5 Division of Licensing DL~/#5 oc;;Nf~i=ie l d I IZ&/84
Mr. David J. VandeWalle cc M. I. Miller, Esquire Isham, Lincoln & Beale Suite 4200 One First National Plaza Chicago, Illinois 60670 Mr. Paul A. Perry, Secretary Consumers Power Company 212 West Michigan Avenue Jackson, Michigan 49201 Judd L. Bacon, Esquire Consumers Power Company 212 West Michigan Avenue Jackson, Michigan 49201 James G. Keppler, Regional Administrator Nuclear Regulatory Commission, Region III 799 Roosevelt Road Glen Ellyn, Illinois 60137 Township.Supervisor Covert Township Route 1, Box 10 Van Buren County, Michigan 49043 Office of the Governor Room 1 - Capitol Buil.ding Lansing, Michigan 48913 Palisades Plant ATTN:
Mr. Robert Montross Plant Manager Covert, Michigan 4go43 U.S.
Environm~ntal Protection Agency Federal Activities Branch Region V Office ATTN:
Region2l Radiation Representative 230 South Dearborn Street Chicago, Illinois 60604 Resident Inspector c/o U.S. NRC Palisades Plant Route 2, P. 0. Box 155 Covert, Michigan 49043 e**
January 26, 1984 Lee E. Jager, P.E., Chief Environmental and Occupational Health Services Administration Michigan Department of Public Health 3500 N. Logan Street Post Office Box 30035 Lansing, Michigan 48909
ENCLOSURE 1l
/..
INTERIM POSITION FOR CONTAINMENT PURGE L
AND VENT VALVE OPERATION PENDING RESOLUTION OF ISOLATION VALVE OPERABILITY Once the conditions listed below are met, restrictions on use of the containment
- purge and vent system isolation valves will be. revised ~ased on our review of your responses to the November 1978 letter justifying your proposed operational mode.
The revised restrictions can be*established separately for each system..
- 1.
Whenever the-containment integrity is required, emphasis should be pl aced on operating the containment in a passive mode as much as possible and on limiting all purging and venting times to as low as achievable.
To justify ventiny or purging, there must be an established need to improve work"ing conditions to perfonn a safety related surveillance or safety related maintenance procedure.
(Examples of improved working conditions wou.ld include deinerting, reducing tenJperature*, humidity*,
and airborne activity sufficiently to pennit efficient perfonnance or to significantly reduce occupational radiation exposures), and
- 2.
Maintain the containment purge and vent isolation valves closed whenever the reactor is not in the cold shutdown or refueling mode until such
- _time as you can show that:
.a. All isolation valves greater th~n 3" *nominal diameter used for conta'inli1ent purge and venting operations are operable under the most.severe design*basis accident flow condition loading*and can c}ose wit~in the tira~ limit stated in your Technical Specifications~
- desiyn criteria or* operating procedures.
The operability of butter-fly valves may, on an interim basis, be de111onstrated by 1 imiti-ng: the
-.~-. -
valve to be np more than 30° to 50° open {90° being full o~en). The maximum opening shall be determined in consultation with the valve supplier. The valve opening must be such that the critical valve parts will not be damaged by DBA~LOCA loads and that the valve will tend to close when the fluid dyn.a,mi_c forces are introtjuced, and
. *b. Modifications, as necessary, have been made to segregate the containment ventilation isolation si9nal s to ensure that, as a minimum, at least
- one of the automatic safety injection actuation signals is uninhibited and operable to initiate valve closure when any other isolation signal may be b 1 oc ked, re~et, o.r overridden.
- Only wl1ere temperature and humidity controls are not in the present design.
e*
ENCLOSURE 2
. CLARIFICATION OF VALVE USAGE J. Purging/venting should be minimizep during reactor operation because the plant is inherently safer with closed purge/vent valves (containment) than with open lfoes which require valve action to provide containment.
(Serious consideration is b~ing given to
- ultimately requiring that future plants be designed such that purging/venting is.no~ required during operation).
- t. Some purging/venting on current plants will be pennitted provided that:
a) purging is needed and justified for safety purposes, and b) valves are judged by the staff to be both operable and reliable, *and
.. c) the estimated.amount of radioactivity _released during the time *required to close the valve{s) following a LOCA.eithei-"
- i.,.does. not cau$e the total dose to exceed the 10 CFR Part 100 Guidelines; then a goal should be established whi~h represents a 1 imi_t on the annual hours *ef purging expecte:d through each particular valve, or. -
ii. causes the ~otal dose to exceed the guideline values; then purging/venting shall be limited to 90 hour0.00104 days <br />0.025 hours <br />1.488095e-4 weeks <br />3.4245e-5 months <br />s/year.*
- 3. Purging/venting should not be permitted when valv~s are being used that are known to be not operable or reliable under transient or accident conditions.
I*
- "<.* z
PURGE/VENT VALVE LEAKAGE TESTS the long term resolution of Generic Issue B-24, "Containment Purging.
During Normal Plant Operation," includes, in part, the implementation of Item B.4 of Branch Technical Positi.on (BTP) CSB 6-4. Item B.4 specifies that provisions should be made for leakage rate testing _of the (purge/vent
. system) isolation valves, individually, during reactor operation. Although
- Item 8.4._does not address the testing frequency, Appendix J. to 10 CFR Part *.
50 specifies a maximum test interval of 2 years.
/
.,,._s a result of the numerous reports on* unsatisfactory performance *of *.the.
- resilient seats for the isolation valves in containment purge and vent lines. ;* :.. *
(addressed in OIE Circular 77-11, dated September 6, 1977), Generic Issue B-20, "Containment Leakage Due to S~al Deterioration," was established to evaluate the matter and establish an appropriate testing frequency for the isolation valves. Excessive leakage past the resilien~ seats of isolation valves in purge/vent lines is typically.caused by severe environmental con-ditions and/or wear due to.frequent use. Consequently, the l'eakage test
- frequency for these va 1 ves should be keyed to the occurrence of severe environ-me.ntal conditions and the use or the valves, rather than the current require-.
ments of 10 CFR 50, Appendix J...
lt~is recommended that*the followi.ng provision. be added to the Jech~_ical
.:~specif*icat'ions for the**leak t~sting of purge/vent line isolation valves:_.
"L.ea'kage integrity tests.. shall be, performed on the containment
. iso1ation valves with.resilient material seals in (a) active*
purge/vent systems (i.e., those which may. be.operated during plant operating Modes l through 4) at least once every thre~
months and (brpassive.. purge systems (i.e., those which must be administratively controlled closed during reactor operating Modes 1 through 4) at least -once every six months."
By* way of clarification, the above proposed surveillance specification is predicated on our expectation that a plant would have a need to *go to cold shutdown several times a year.
To cover the possibility that* this may not occur, a maximum test interval of 6 months is specified. However, it is not -0ur intent to require a plant to shutdown ju~t to conduct the valve
.leakage integrity tests. If licensees anticipate long duration power aper~
ations with infrequent shutdown, then installation of a leak test connection that is accessible from outside containment may be appropriate. This will permit simultaneous testing of the redundant *.valves. It will not be possible to satisfY. explicitly the guidance of !~em B.4 of BTP CSB 6-4 (wh.ich states that valves should be tested individually), but at let'.st some testing of the valves during reactor operation will be possible.
~
e**
- The* purpose of the leakage integrity tests of* the isolati-on valves* in the containment purge and vent.-lines is to identify excessive degradation of.
.
- the resilient seats for these valves. Therefore, they need not be conducted with the precision required for the Type C isolation valve tests in 10 CFR Part 50, Appendix J. These tests would be perfonned in addition to the quantitative Type C tests required.by Appendix J and would not relieve the licensee of the responsibility to confonn to the requirements of Appendix J=
In view of the wide variety of valve types and seating-materials, the.
acceptance criteria for such tests should be developed on a plant-specific basis.
t CONTA!NMENT SYSTEMS LIMITING CONDITION FOR OPERATION r
3.6.1.7 The containment purge supply and exhaust isolation valves may be open for safety-related reasons [or shall be locked closed]. The containment vent line isolation valves may be open for safety-related reasons [or shall be l~cked closed].
APPLICABILITY:
MODES l, 2, 3, and 4.
ACTION:
l;*
(For plants with valves closed by technical sp~cification)
~ith one containment purge supply and/or one exhaust isolation valve open, close the open valve(s) within one hour or be in at least HOT STA?JDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and* in. COLD SHUTDOWN within the following.
30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
(For p~ants with valves that may be opened.by technical specifications) 1.-~*with.one containment purge supply and/or o_ne exhaust isolation *or vent v.alve inoperable,* close* the associated OPERABLE valve and either restore
- the inoperable valv*e to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or *lock. the OPERABLE v~lv~ closed *
- 2.
Opera ti on may then continue until perfo*rmance of ~he next required valve test provided that the OPERABLE valve is verified to be. locked closed at least once per 31 days.
- 3. *Otherwise, be in at least HOT*STANDBY within the next six hours and in COLD SHUTDOWN within the follow.i.ng 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
- 4. the provisions of Specification 3.0.4 are.not applicable.
SURVEILlANCE REQUIREMENTS
- 4. 6. 1. 7. 1 The
- -inch containment purge supply* and exhaust i sol ati on valves and the
-inc~vent line isolation valves shall.be determined locked closed at least--Once per 31 days.
4.6.1~7.2 The valve seals of the purge.supply and exhaust isolation valves and the vent line isolation valves shall be replaced at least one per._years.
3/4 6~10
CONTAINMENT SYSTEMS 3/4 4.6.3 CONTAINMENT ISOLATION VALVES LIMITING CONDITION FOR OPERATION 3.6.3 The containment isolation valves specifie.d in Table 3.6-1 shall be*.
OPERABLE with isolation times as shown in Table 3.6-1.
APPLICABILITY:
MODES 1, 2, 3 and 4o ACTION:
With one o~ ~or~ oi the isolation valves(s) specified in Table 3.6-1 inoperable, maintain at least one isolation valve OPERABLE in each affected penetration that is open and ~ither:
- a.
Restore the inoperable valve(s*) to.OPERABLE status wi.thin 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> or*
- b.
Isolate each affected penetration within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> by use of at least one deactivated automatic valve secured in the isolation *position,
- or
- c. *Isolate each affected penetration withi"n 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> by use of at least one closed manual. valve or blind flange; or
- d.
Be in at least HOT STANDBY within the next.5. hours and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
SURVEILLANCE REQUIREMENTS 4.6.3.l *The i.solation valves specified in Table 3.6-l shall be demonstated OPERABLE prior to returning the valve to service after maintenance, repair or replacement work is performed. 9n the valv7 or its associat:d.act~ator, ~antral or power circuit by perfonnance of a cycling test, and verification of isola-tion time
- 3/4 6-14
CONTAINMENT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued)..
4.6.3.2 Each isolation valve specified in Table 3.6-1 shall be.demonstrated OPERABLE during the COLD SHUTDOWN or REFUELING MODE at least once per 18.
months by:
- a. Verifying that on a Phase A containment isolation test signal, each Phase A isolation valve actuates to its isolation position.
- b. Verifying that on a Phase B containment isolation test signal, each Phase B isolation valve actuates to its isolation position.
4.6.3.3 The isolation time of each power operated or automatic valve of Table 3.6-1 shall be determined to be within its limit* when tested pursuant to Specification 4.0.5.
4*.6.3.4 The.containment purge a11d vent isolation valves shall be demo.nstated OPERABLE at intervals not to exceed months.
Valve.OPERABILITY shall be determined by verifying that when the measuued leakage rate is added to the leak~ge
- . ra\\:es de.tennined pursuant to Specification 4.6.1.2.d for all other Type B and
- C penetration,, the combined leakage rate* is less than or equal to 0.60La.
- *However, the leakage rate for the contairyment purge and vent isolation valves
- shall be compared to the previously :measured 1 eakage rate to detect excessive
- va 1 ve degradation.
-=-~--*
3/4 6-15
e*
- ENCLOSURE 5 ADDITIONAL INFORMATION REQUIRED TO EVALUATE PALISADES PLANT CONFORMANCE TO GUIDELINES OF BTP CSB 6-4 REVISION 1, "CONTAINMENT.PURGING DURING NORMAL OPERATION 11
- 1.
Provide an analysis of airborne radiation released to the environment prior to purge system isolation following a LOCA.
- 2.
Provide a discussion of the provisions to insure that isolation valve closure will not be prevented by debris which could potentially become entrained in the escaping air and steam.
Installation of debris screens is one acceptable method of accomplishing this function.
If no provisions are considered necessary provide information to justify this cone 1 us ion.
- 3.
It is our recommendation that you commit to limiting the use of the purge/vent system to a specified annual time commensurate with plant operatfonal safety needs.
Provide such a commitment or justification why such a limitation is considered unnecessary.
- 4.
We request that you propose Technical Specification chan~es incorporating the test requirements set forth in Enclosure 3 together with the details of your proposed test program.
If the results of current ~hd past surveillance and operating experience are believed to demonstrate leak tightness of those valves, provide this information as justification for not modifying the surveillance requirements.