Workshop

DOE-STD-1024-92

uncertainty for the Savannah River Site. This figure shows that the

revised LLNL mean results are significantly lower than the earlier LLNL

results. Also shown in Figure 7 are the results of the LLNL\EPRI

correction factor with (Choice 2) and without (Choice 1) LLNL-AE5. It

appears that for the Savannah River Site that the Choice 1 correction

factor (using the existing LLNL results without LLNL-AE5) will more

accurately reflect the assessment of mean seismic hazard when future

probabilistic results are finalized.

While the specific degree of uncertainty assessment is likely to change

from site to site, the preliminary Savannah River results suggest that the

existing LLNL mean hazard results may substantially overestimate the

mean hazard, consistent with the previous assessment that the mean

hazard curves should not be directly used. Based on this information, the

SWG position is that the pseudo-mean correction factor should be based

on the existing LLNL results without LLNL attenuation expert 5.

14.

WORKSHOP

(OR-5, EH-6)

Comments have indicated that a workshop on the development and

utilization of this Standard would be beneficial. This workshop would

include the seismic working group and consultants, DOE field offices, and

M&O contractors. We plan to have this workshop although the specific

date has not been selected.

15.

NEW INFORMATION

(EH-5)

Recent information developed by the CSD Program may be helpful in

resolving some of the uncertainties in the EUS, and may be useful in the

development of a "final standard" for both eastern and western DOE

locations. We agree that a summary should be provided to SWG and

passed on to contractors as appropriate.

16.

CORRELATION OF MEDIAN ESTIMATES

(RW-10)

The older TERA, Inc. curves are best correlated with median hazard

estimates because they were based on "best-estimate" values without the

explicit quantification of modeling uncertainty. In any case Table 3

indicates that the TERA, Inc. values are conservative compared to the

Standard position values.

17.

ACCOUNTING FOR SITE CONDITIONS

(INEL-1, RW-7, RW-8)

Comments correctly state that site geological conditions need to be

considered in seismic analysis. There is a guidance document being

developed to address seismic hazard data criteria needed, currently

A-27