ML19260A574
| ML19260A574 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 11/23/1979 |
| From: | Lundvall A BALTIMORE GAS & ELECTRIC CO. |
| To: | Reid R Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19260A575 | List: |
| References | |
| RTR-NUREG-0578, RTR-NUREG-578 NUDOCS 7911270288 | |
| Download: ML19260A574 (3) | |
Text
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BALTIMORE GAS AND ELECTRIC COMPANY GAS AND ELECTRIC DUILDING DALTlMORE, MARYLAN D 212O3 Aamum E. LuNovALL JR.
vier pass.oc,
se, November 23, 1979 Office of Nuclear Peactor Pegulation U.S. Nuclear Pegulatory Commission Washington, D.C.
20555 Attn:
Mr. Robert W. Reid, Chief Operating Reactors Branch #h Division of Operating Reactors
Subject:
Calvert Cliffs Nuclear Power Plant Unit Nos. 1 & 2, Docket Nos. 50-317 & 50-318 Follow-up Actions Pesultinc from 'IMI-2 Incident
_ Auxiliary Feedvater System Modifications Gentlemen:
Additional descriptive information was requested by NBC personnel during a telephone conference on November 20 concerning the troposed modification to the control of the auxiliary feedvater system at Calvert Cliffs.
Auditional informtion on instrument power cources was specifically requested.
The modification proposed by EG&E to meet the control grade auto start requirement of NUREC 0578 was described in a letter to you dated November 9, 1979 The following is a list of four enclosures included with this tran N ttal:
Enclosure No. 1:
Existing Aux Feed System Enclosure No. 2: Layout, Wiring & Connection Diagram, Feedvater Control Systems 11 & 121C35 & 1C36 Aux Panels Enclosure No. 3: Schematic Diagram, Unit 1 Aux Feedvater Actuation System.
Enclosure No. h: Power Supply Data Table These enclosures and our letter of November 9,1979, p ovide a complete description of the changes ve propose to meet the January 1, 1980, requirement for a control grade auto start of auxiliary feed system.
A Technical Specificatien change vill be submitted which vill require a test of the auto initiation logic every 31 days.
1696 276 7933gyg } [ [
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Mr. Robert W. Reid November 23, 1979 Note that power separation has been maintained to ensure that the system is single failure proof.
It should be noted once again that plant operating procedures vill be raodified to require that the auxiliary feed regulatina valves be kept shut after main feed is established. This vill be done to prevent continued auxiliary feed to a ruptured steam generator, a situation which is still under evaluation to determine whether a safety question exists with regard to containment overpressurization or excessive coolsovn of RCS. Your review and,oproval of the proposed pump auto start is needed as soon as possible.
With regard to the January 1981 requirement for safety grade automatic initiation of this system, we are beginning design of modifications to the control of the existing system, which vill automatically initiate auxiliary feed, detect a ruptured steam generator, and control steam generator level accordingly. We in. tend to install this by January 1981.
1 [yours, Very t
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.,- 4 w A. E. Lundvall, Jr.
Vice-Pres' dent - Supply i
AEL/mlk
Enclosure:
cc:
J. A. Biddison, Esquire G. F. Trowbridge, Esquire E. L. Conner - NRC 1696 277
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a Enclosure No. 4 POWER SUPPLY DATA TABLE
's'0WER SUPPLY UNIT DEVICES PRI/STDBY FACILITY ASSOC. S/G 1
, Stm from 11 to SGFPT Edr 1
Stm from 12 to SGFPT Ndr 1
HIC 4511 1Y10 B
Aux Feed to 11 1
HIC h512 1YO9 A
Aux Feed to 12 1
HIC 3987 1YO9 A
NA 1
HIC 3989 1Y10 B
NA 1
Auto Init.
1YO1/1YO9 DA/A Ioss of Main Feed to 11 1
Auto Init.
1YO2/1Y10 DB/B Ioss of Main Feed to 12 2
HIC h511 2YO9 A
Aux Feed to 21 2
HIC 4512 2Y10 B
Aux Feed to 22 2
HIC 3987 2YO9 A
NA 2
HIC 3989 2710 B
NA 2
Stm from 21 to SGFPT Hdr 2
Stm from 22 to SGFPT Rdr 2
Auto Init.
2YO1/2YO9 DA/A Ioss of Main FW to 21 2
Auto Init.
2YO2/2Y10 DB/B Loss of Main FW to 22 Note: Aux FW Reg. CV's F.O. on loss of air & power 1696 278
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