ML19261A411
| ML19261A411 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 01/12/1979 |
| From: | Lundvall A BALTIMORE GAS & ELECTRIC CO. |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7901180149 | |
| Download: ML19261A411 (3) | |
Text
e BALTI M OR E G AS AN D E LECTRIC CO M PANY GAS AN D CLECTRIC BUILDING B ALTI M O R E, M A RYL A N D 21203 ARTMUR s. LUN DVALL,d A.
un p.c,.c c.
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Office of !!uelesr Reactor Regulation U.S. IIuelear Regulatory Commission Washington, D.C.
20555 Attn:
Mr. Robert W. Reid, Chief Operating Reactors Branch #h Division of Operating Reactors
Subject:
Calvert Cliffs I!uclear Power Plant Unit lio.1 & 2, Docket I!o. 50-317 & 50-318 Centainrent Parging During I!cmal Plant Operation
Reference:
IIP" letter dated I;ovember 29, 1976 from F.W. Reid to A. E. Lundvall, Jr.. same subject Gantlemen:
The referenced letter requested that we either co==it to cease all contrtin=ent purging during hot shutdown. hot standby, startup and power operation or thst we provide a justificatien for continuing purging. If we chose to do the latter, we were also to de enstrate that the purge isolation valves would close under postulated design basis accident con-ditions. In addition, we were to prepose a Technical Specification governing our intended purring operations, and we were to provide a schedule for cogletion of our (femal) evaluation justifying continued (limited) purging during power operation.
Pending I!RC's review of this evaluation, we were to either cease (or limit to an absolute mininum) purging.
An additional related requirement of the referenced letter was for un to review the design of all safety actuation signal circuits which have manu11 overrides to ensure that overriding one signal does not disable other safety functions and that all manual overrides are adequately annunciated and contain sufficient physical features to allow adequate administrative control.
The following inforstion is provided relative to your letter:
1.
We intend to continue purging on a limited basis not to exceed 90 hours0.00104 days <br />0.025 hours <br />1.488095e-4 weeks <br />3.4245e-5 months <br /> per year:
?.
A draft technical specification to cover limited purging has been developed and is enclosed for your review and comments; 790118o199
Mr. R. W. Reid January 12, 1979 3
Tne Purge Air Isolation Valves were purchased under a design speci-fication calling for closure of the valves against design basis LOCA conditions & a certificate of co=pliance to the design specification was issued by the vendor; h.
Although purging is not relied on as the primary means of reducing contain=ent te=perature and humidity, the ability to purge en a li-ited basis is both necessary and justified. operating experience has shown that contain=ent access, for routine purposes such as taking readings or sa=ples as well as for maintenance and for unplanned reasons, is often only possible after purging to reduce te=perature or radioactivity levels.
5 As requested, we have conducted a review of "the design of all safety actuation signal ci.cuits which incorporate a manual override feature'.
During the initial design of the plant, the use of the manual override feature was kept to a minimum. Additionally, an effort was made to annunciate such overrides where practical. Consecuently, most safety actuation signals cannot be manun11y overridden, and the major portion of those which can be overridden confom to the guidance in your letter of having physical features for administrative control and of being annunciated. However, there are several exceptions, which are listed below. These are being carefully evaluated to detemine what actions are necessary to preclude improper use of the override feature.
a.
Switchgear Roo= air-conditioning co= pressor b.
Control Roo= air-conditioning ec= pressor c.
Boric Acid pu=ps d.
Diesel Generator feeder breakers
- 12 & #22 Service Water Heat Exchangers Salt Water Inlet Vcives c.
f.
- 12 & #22 Co=ponent Cooling Water Heat Exchangers Salt Water Inlet Valves We intend to et,lete our evaluation of these components and to submit any resultant design or procedural modifications for your review within 90 days.
In the meantime, we will use administrative controls to prevent improper use of these overrides.
6.
Your letter, specifically the last so-tence of paragraph (2), stated that we should provide a schedule for ;o=pletion of an evaluation justifying continued limited purging during power operation. It is unclear to us what is being requested. However, pending your review of the infomation submitted herein we intend to limit purging to an absolute minimum, not to exceed 90 hours0.00104 days <br />0.025 hours <br />1.488095e-4 weeks <br />3.4245e-5 months <br /> per year.
We hope this reply is responsive to the intended require =ents of your letter. Please do not hesitate to contact us if you need additional infor=ation or if you have co=ments on our draft te Mical spec $fication.
Si". re', ye s
/'
'E. LEIm '
[
Vice-Preside.o - Supply cc - J. A. Biddison, Esquire J. W. Brothers (Bechtel)
G. F. Trowtridge, Esquire P. W. Kruse (CE)
E. L. Ccnner, Jr. (NRC)
CONTAINMEi4T SYSTEMS
~
3/4. 6. 7 Containment Furae System LIMITING C0i;DITION FOR OPERATION 3.6.7.1 The automatic isolation valves in the containment purge lines may l
be opened for a maximum of 90 hours0.00104 days <br />0.025 hours <br />1.488095e-4 weeks <br />3.4245e-5 months <br /> per calendar year.
APPLICABILITY: Modes 1, 2 and 3*
't ACTION:
With any containment purge automatic isolation valve open for greater than 90 hours0.00104 days <br />0.025 hours <br />1.488095e-4 weeks <br />3.4245e-5 months <br /> in one calendar year, close the open valve (s) within one hour or be in at least HOT STANDBY 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 />.
I i
- With pressurizer pressure 21750 psia (ALVEitT Cliffs utJuTL I
- 2 b2 AFT'