ML20010F486
| ML20010F486 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 09/03/1981 |
| From: | Hukill H METROPOLITAN EDISON CO. |
| To: | Stolz J Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0680, RTR-NUREG-0737, RTR-NUREG-680, RTR-NUREG-737 NUDOCS 8109100276 | |
| Download: ML20010F486 (2) | |
Text
e a Metropolitan Edison Company Post Office Box 480 l l-L Middletown, Pennsylvania 17057 Writer's Direct Dian Number September 3, 1981 Llt 239 Office of Nuclear Reactor Regulation Attn: John F. Stolz, C.tief Division of Licensing Operating Reactors Branch No. 4 U. S. Nuclear Regulatory Commission Washington, D.C.
20555
Dear Sir:
Three Mile Island Nuclear Station, Unit 1 (TMI-1)
Operating License No. DPR-50 Docket Nc. 50-289 RCS liigh Point Vents (LM-21)
In accordance with NUREG 0737 and NUREG 680 Supplement 3, the following documents were provided to Mr. R. Jacobs, of your staf f, on August 24, 1981:
Document No.
Title GPUNC System Design
" Reactor Coolant System 1'enting" Description (SDD)
SDD-222A, Div. 1, Rev. O dated 1/8/81 SDD-222A, Div. II, Rev. O
" Reactor Coolant System Venting" (E-222-21-001, Rev. O
" Reactor Coolant System Vent to Containment Flow Diagram" IC-231-21-002, Rev. O
" Waste Disposal Gas System Reactor Coolant Drain Tank Vent Flow Diagram" ID-222-17-001, Rev. O
" Electrical Elm entary Diagram Reactor Coolant Vent ystem, Channel A" ID-222-17-002, Rev. 1
" Electrical Elementary Diagram--Reactor Coolant Vent System Channel B" ID-231-17-003, Rev. O
" Electrical Elementary Diagram Waste Gas Disposa.' system--Reactor Coolant Drain
\\
Tank Venting h
IB-664-42-001, Rev. O
" Instrument Loop Diagram--RC Loop A High g
Point Vent" IB-664-42-002, Rev. O
" Instrument Loop Diagram--RC Loop.R High r oM" General Pubt UtMties System 8109100276 810903 ison Company is a9tU.
Y PDR ADOCK 05000289 P
O Mr. John F. Stolz LlL 239 l
IB-664-42-003, Rev. 1
" Instrument Loop Diagram--Pressurizer Vent" IB-664-42-004, Rev. O
" Instrument Loop Diagram--Renator Head Vent" Please note that Division 1 of the SDD covers basic system criteria and that Division II describes the system, as actually designed, in detail. Livision II may be used to follow the system design as shown on the various system drawings and also provides the basis for drafting detailed plant operation procedures.
Operating information furnished in Division II should be sufficient for procedures for operator use of the vents.
Since the RCS High Point Vent System is a safety grade design it can be considered a qualified system for bringing the plant to cold shutdown.
A revision to Division II of the SDD which will detail the use of the pressurizer vent for achieving cold shutdown is currently under preparation.
The TMI Restart Report section 2.1.2.2 discusses the long term modifications planned for the reactor coolant system. The system piping diagram (dwg. IE-222-21-001) shows only one train for the reactor vessel head vent whereas the TMI-l Restart Report indicates that there would be two trains. The reason that the actual design has only one train is that NUREG 0737 indicated that vent systems are not required to have redundant paths and we don't believe two paths are necessary.
The TMI-l Restart Report indicates that vent system piping within the RCS pressure boundary would be Class N-1.
The actual design as shown on the enclosed piping diagram shovs the vent system piping (l" smaller) as Class N-2.
TMI-l existing design basis specifies that RBS piping 1" nominal size and smaller need not be Class 1) per the criteria of the original B&W design basis for TMI-l RBS piping.
Sincerely, g.,.
H
. Hukill Director, TMI-1 HDH: CJS:vj f cc:
B. H. Grier L. Barrett H. Silver
. Jacobs
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