ML20133K507
| ML20133K507 | |
| Person / Time | |
|---|---|
| Issue date: | 07/23/1985 |
| From: | Hulman L Office of Nuclear Reactor Regulation |
| To: | Silberberg M NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES) |
| Shared Package | |
| ML20133K471 | List: |
| References | |
| RTR-NUREG-0956, RTR-NUREG-956 NUDOCS 8508120253 | |
| Download: ML20133K507 (2) | |
Text
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UNITED STATES E
NUCLEAR REGULATORY COMMISSION o
y E
WASHINGTON, D. C. 20555
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JUL 2 31985 MEMORANDUM FOR: iMelvinTSilberberg; Chief Fuel Systems Research Branch Division of Accident Evaluation, RES FROM:
L. G. Hulman, Chief Accident Evaluation Branch Division of Systems Integration
SUBJECT:
CONSEQUENCE CALCULATIONS FOR NUREG-0956 My previous memorandum of July 22, 1985 on the above subject contained, among other information, several complementary cumulative distribution functions (CCDF's) showing the distribution of calculated early and latent cancer fatalities.
We have just received a letter from Sandia (See Enclosure 1) informing us that their previously recommended procedure, which was used to obtain these curves, is not correct. This is due to a possible error in summing the contributions of the two different population segments (95% evacuating, 5% non-evacuating) in obtaining the CCDF's.
Follow-up calls between the staff and Sandia on July 22 and 23, 1985 have indicated that the computed mean values of these quantities as well as the latent cancer fatality CCDF's are correct, but that the early fatality CCDF's may be in error.
Internal discussion among the staff has indicated that the error, if any, is likely to be small.
Nevertheless, we plan to recompute these CCDF's.
Sandia has begun code modifications to obtain the correct CCDF's. We will coordinate the changes between Sandia as well as ORNL to see that the staff version of CRAC2 at NIH is appropriately modified. We expect recomputed CCDF's to be available on Monday, July 29, 1985.
l In view of the above information, I recomend that the CCDF's provided I.
in my memo of July 22, 1985 be regarded as tentative, pending their recomputation.
f.O
. Hulman, Chief Accident Evaluation Branch Division of Systems Integration
Enclosure:
As stated cc:
See Next Page 8508120253 850729 PDR NUNEQ 0956 C PDR
3 cc:
D. Ross R. Bernero T. Speis E. Jordan F. Gillespie S. Schwartz D. Muller L. Bell R. Buck M. Mcdonald L. Soffer G. Suh K. Thornton E. Podolak J. Mitchell D. Cleary I. Spickler