ML19256E730
| ML19256E730 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 10/25/1979 |
| From: | Crouse R TOLEDO EDISON CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| IEB-79-24, NUDOCS 7911150098 | |
| Download: ML19256E730 (3) | |
Text
DC TOLEDO October 25, 1979 EDISON Docket No. 50-346 AcsAno P CnOUSE vo %
License No. NPF-3 hQ7pg Serial No. 1-97 Mr. James C. Keppler Regional Director, Region III Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137
Dear Mr. Keppler:
This letter transmits information for Davis-Besse Nuclear Power Station Unit No. 1 as requested by IE Bulletin 79 24 concerning freeze protection of safety-related process, instrument, and sampling lines during extremely cold weather. addresses a review of all safety-related freeze protection equipment and details corrective actions and.:ontin-gency plans to ensure that all safety-process, instrument, and sampling lines subjected to extremely cold weather are adequately prote.:ted.
Toledo Edison considers the attached information as a sufficie >t and satis-factory response to IE Bulletin 79-24.
However, if any questicas arise con-cerning this information please contact us at your convenience.
Very truly yours, ff
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1333 098 T?C/TDM/DLM/ daw Attachment j
THE TOLEDO EDISON COMPANY EDISON PLAZA 300 MADISON AVENUE TOLEDO. OHIO 43652 7911150 Cf[
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I Docket No. 50-346 License No. NPF-3 Serial No. 1-97 October 25, 1979 Page 1 RESPONSE TO IE BULLETIN NO. 79-24 Davis-Besse Nuclear Power Station Unit No. 1 Bulletin No. 79-24 requested a review to determine that adequate protective measures have been taken to assure that safety-related process, instrument, and sampling lines do not freeze during extremely cold weather.
The following safety-related items have been evaluated to require correct-ive action to prevent freezing during extremely cold weather.
The evalua-tion resulted in extensive engineering work and material acquisitions to permanently correct existing problems.
A.
Borated Water Storage Tank (BWST) Level Instrumentation.
1.
BWST Level Transnitter, LT1525A Heat Tracing CKT #1Q 2.
BWST Level Transmitter, LT1525A Source Line Heat Tracing CKT #3Q 3.
BWST Level Transmitter, LT1525B Heat Tracing CKT #5Q 4.
BWST Level Transmitter, LT1525B Source Line Heat Tracing CKT's #7Q, 8Q 5.
BWST Level Transmitter, LT1525C Heat Tracing CKT #9Q 6.
BWST Level Transmitter, LT1525C Source Line Heat Tracing CKT #11Q 7.
BWST Level Transmitter, LT1525D Heat Tracing CKT #13Q 8.
BWST Level Transmitter, LT1525D Source Line Heat Tracing CKT's #15Q, 16Q The existing O'Brien Model C-3 instrument enclosures are bein a replaced with O'Brien Model A-1 enclosures, as the existing enclosures wera modified dur-ing original construction to fit the instrument by cutting large areas in order to allow the enclosure top to slide down over the instrument, which defeated the overall purpose of the enclosure.
The heat tracing, sensing elements, contolling elements, and insulation for the instruments and lines are being upgraded.
B.
High Pressure Injection (HPI) pumps recirculation line.
1.
HPI Pump Recirculation Line, 3"-HCC-91 Heat Tracing CKT's #17,20,21,2e The freeze protection system for the line is being split into two portions.
The Heat Tracing CKT's 17 and 24, and their controls within the pipe tunnel below the Borated Water Storage Tank will be upgraded.
Redundant Heat Tracing CKT's 20 and 24 to protect the portion of the piping ortside the pipe tunnel to the top of the BWST will be added.
1333 099
Docket No. 50-346 License No. NPF-3 Serial No. 1-97 October 25, 1979 Page 2 The upgrading of insulation involves the removal of asbestos and/or fiberglass insulation and its aluminum covering, and replacing it with calcium silicate insulation of proper thickness with aluminum covering.
The above corrective actions are being implemented now that the engineer-ing has been complcted and materials have been procured.
The work will be completed prior to the Winter of 1979.
Other lines associated with the BWST.
1.
BWST Vacuum Breaker, PSV2762 (Safety Related) 2.
BWST Drain Line, 2"HCB-18 (Safety Related)
The existing heat tracing is being checked and will be replaced as necessary.
The insulation is being upgraded.
The work will be completed prior to the Winter of 1979. Upon the receipt of control cabinets and other equipment, upgrading of the heat tracing circuits will be done.
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