ML19289C376

Responds to NRC 781121 Request for Aid W/Licensing Review Re Postulated Dbda & Loss of Forced Circulation Accidents. Concludes Each of the New Postulated Cases Results in Max Temp No Greater than FSAR-assumed Worst Case

ML19289C376
Person / Time
Site:	Fort Saint Vrain
Issue date:	12/21/1978
From:	Ball S OAK RIDGE NATIONAL LABORATORY
To:	Schamberger R NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES)
Shared Package
ML19289C364	List: ML19289C374 ML19289C376
References
NUDOCS 7901120107
Download: ML19289C376 (5)

Text

OAK RfDGE NATIONAL LABORATORY CEEPATCO SV UNION CARBIDE CORPORATici1 NUCLEAR HV1510N e

Po1T OFFICE sox Y cAE RioGE. TENNE 15EE 3700 Dece=ber 21, 1978 Dr. R. ' Schamberger, Chief Experimental Gas Cotied Reactor Safety Research Branch Division of Reactor Safety Research U.S. Nuclear Regulatory Commission Wasnington, D. C. 20555

Subject:

Response to DSS Request of November 21, 1978 for Assistance with Fort St. Vrain Reactor Licensing Review This letter responds to a request by DSS for CRNL to provide additional i

calculations of postulated D3DA and LCFC accidents for Fort St. Vrain (FSV).

The intent of ths request is to determine if initial conditions other than those specified in the FSAR could lead to worse conditions during a DBDA or LOFC accident. Specific conditions chosen are points along the power-to-flow ratio vs core thermal power curve (Fig. 3.1-2 from the FSV Technical Specifications),

shown in Attachment 1. The 5 points marked on the curve were chosen as initial conditions for the nalyses. A sixth point, with an initial power of 102 and an initial flow of ',3.5%, is also included to represent compounded worst-case measurement uncertainties.

Since detailed calculated core input parameters and functions are not available for these analyses, the following assumptions are made based on the GA dataz supplied for the FSV analyses done by ORNL last May:

1. Equilibrium core (EQSB3) peaking factors and associated refueling region curlet temperatures. In order to obtain a heat balan

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