ML20107M935
| ML20107M935 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 11/09/1984 |
| From: | Hukill H GENERAL PUBLIC UTILITIES CORP. |
| To: | Stolz J Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737 5211-84-2279, NUDOCS 8411140352 | |
| Download: ML20107M935 (5) | |
Text
-
GPU Nuclear Corgx> ration Nuclear
=g;S:
8 48o Middletown. Pennsylvania 17057-0191 717 944-7621 TELEX 84-2386 Writer's Direct Dial Number:
November 9, 1984 5211-84-2279 Office of Nuclear Reactor Regulation Attn:
J. F..Stol', Chief z
Operating Reactor Branch No. 4 Division of Licensing U.S. Nuclear Regulatory Commission Washington, D. C.
20555
Dear Mr. Stolz:
Three Mile Island Nuclear Station Unit 1 (TMI-1)
Operating License No. DPR-50 Docket No. 50-289 NUREG-737, Supplement 1 - Regulatory Guide 1.97 Revision 3 Section 6.2 of Supplement 1 of NUREG-737 pertaining to Regulatory Guide 1.97, requires each licensee to submit a report describing how it meets the reco-mmendations of Regulatory Guide 1.97, " Instrumentation for Light Water Cooled Nuclear Power Plants to Assess Plant and Environs Conditions During and Following an Accident".
In the GPU Nuclear Corporation transmittal on the subject dated October 1, 1984, we provided a report detailing comparison of the specific recommendations of Regulatory Guide 1.97 with the Three Mile Island Unit I design. With respect to the Regulatory Guide 1.97 recommenda-tion regarding neutron flux monitoring instrumentation we identified that our review of this variable was continuing, and that the Commission would be in-formed.
TMI-1 is equipped with a neutron flux monitoring system composed of power, intermediate and source range monitors. The only post accident design basis functions provided by the neutron flux monitoring system are reactor trips involving high neutron flux (power rante monitor). Of the spectrum of postulated accidents resulting in harsh environmental conditions inside containment, a high flux signal is the principal initiator of a reactor trip for the rod ejection accident only. The trip signal is generated in a time period small in comparison with the time required for the containment atmos-phere to become a harsh environment.
The design basis events evaluated for TMI-1 as part of the license applica-tion (Chapter 14 of the Final Safety Analysis Report) do not postulate as credible a return to criticality following shutdown resulting from any design basis accident. Thus, the source and intermediate range monitors are not required to perform any safety related post accident function.
8411140352 841109 DRADOCK05000g ogg GPU Nuclear Corporation is a subsidiary of the General Public Utilities Corporation
'f
Mr. John F.-Stolz 5211-84-2279 Page 2 Therefore, the existing TM1-1 neutron flux monitoring system is deemed appropriate for its functions within the design basis, and is not required to be qualified for harsh post accident environmental conditions. However, for accidents beyond the design basis and in response to the Regulatory Guide-1.97 recommendation, GPUN is committing to install " post-accident" neutron flux monitoring capability which will be installed during the second refueling outage following restart (Cycle 7 Refueling). This new monitoring equipment will be qualified to withstand post accident environmental con-ditions. Accordingly, page 1 of the Regulatory Guide 1.97 comparison which identifies NRC's Regulatory Guide 1.97. criteria for neutron flux monitoring, has been revised to include - this commitment, and the justifica-tion on page la of the original report has been deleted.
Also attached is a revision to page 31 (Primary System Safety Relief Valve Position or Flow Through or Pressure in Relief Valve) of the Regulatory Guide 1.97 report, correcting a typographical error.
Sincerely, sWW#
Director, TMI-l HDil/SK/CWS/kds Attachments l
l 1
- -.' GPU Nuclear Corporatien Revision 1 Three Mila Island, Unit 1 R.G. 1.97 REVISION 3 - INVENTORY & COMPLIANCE TABLE 7
Variable Typei Category
(
Neutron Flux B
1
> System Identification
> Nuclear Instrumentation System
- )
CRITERIA NRC PLANT SPECIFIC
.> Environmental Qualification > Yes
> See Coments (Below)
>lnvironnent
>TeTsiic Uui1TfTcitToi - -
7 Yei - - - - - - - - - - >
> Redundancy
> Yes
>Nuibir oT Ne3uidint thinneTsi Y - - - - - - - - - -
.)
> Power Source
> 1E 1
> Channel Availability
> Yes i
> Quality Assurance-
> Yes i
> Control Room Display
> Indicated
> Continuous
> Neco did- - - - - - - -
I fontinuous/On Demand
- )
> Range
> 10-6 o 100% full power t
> Interface-
> Yes
{
> Servicing. Testing & Calib. > Yes
> Human Factors
> Yes I
> Direct Measurement
> Yes or no
> SCHEDULE: Post accident neutron flux monitoring capability will be provided
-during the second refueling outage following restart. Details of system design will'be developed as part of the design process.
>COBOENTS: TMI-1 currently does not have post accident neutron flux monitoring capability. This function is not required as part of the TMI-1 design basis.
4 j
1
( ) As per attached notes non-compliant
- .not applicable Page 1 of 76
GPU Nuc1:ar Corporaticn R2 vision 1 Three Mile Island, Unit 1
+
R.G. 1.97 INVENTORY & COMPLIANCE TABLE JUSTIFICATION Variable:
Neutron Flux DELETED I
i Page la of 76 4
,-.,-,.,,yy-m--,-,,,,m,p,,n.,,,n,,,,.
,,rn
,_wn_wmgn,,e,w-,--e.---,,,,-,,-new,, -,
GPU Nucl:ar C:rporation R:visicn 1 Three Mila Island, Unit 1 R.G. 1.97 REVISION 3 - INVENTORY & COMPLIANCE TABLE Variable Ty[Le Category Primary System Safety Relief Valve D
2 Positions or Flow Through or Pressure in Relief Valve
> System Identification CRITERIA NRC PLANT SPECIFIC
> Environmental Qualification > Yes
> No*(9)
> Environment
> Harsh
>Seismii i{uilTfTcitToi - -
> No
> No
> Redundancy
> No
> No
> Number of Redundant ChanneTs>
> Power Source
> Non-1E/UPS
> IE Inverter
> Channel Availability
> Yes or no
> Yes (10)
> Quality Assurance
> Yes
> Yes (11)
> Control Room Display
> Indicated
> Continuous /On Demand
> Continuous
>~ Recordid~
-~~~~~~~
> Ilo- ~ ~ ~ ~ ~ ~
> Dn Femand
> Range
> Closed - not closed
> Closed - not closed
> Interface
> Yes
> Yes (12)
> Servicing, Testing & Calib. > Yes
> Yes (13)
> Human Factors
> Yes
> Yes (14)
> Direct Measurement
> Yes or No
> Yes (15)
> SCHEDULE:
Installed.
> COMMENTS:
( ) As per attached notes non-compliant not applicable Page 31 of 76
,