Editorial Comments

DOE-STD-1024-92

85th/median ratio between LLNL and EPRI. The approach chosen was

based on the most stable estimate (the median) and the inclusion of

uncertainty based on the fractiles between 15th and 85th percentiles

between the two studies.

The probabilistic method in the Army Technical Manual uses relatively old

probabilistic results developed by the USGS. As discussed in the response

to previous comments, the LLNL and EPRI results represent improvements

in seismic hazard characterization, particularly the quantification of

modeling uncertainty.

11.

EDITORIAL COMMENTS

(NS-8, NS-9, LLNL-6, LLNL-11, OR-4, RW-9, RW-11 - RW-16)

Reflected in revised Standard.

12.

CLARIFY UCRL-15910 (DOE-STD-1020)

(AL-1)

This comment addresses issues currently present in UCRL-15910 (DOE-

STD-1020) which have been misinterpreted in their use. The first is the

issue of hazard classification. The comments correctly state that UCRL-

15910 (DOE-STD-1020) is not a hazard classification document. The

hazard classification is to be determined independently of UCRL-15910

(DOE-STD-1020). Secondly, there has been confusion in the interpretation

of the DBA occurrence probability, as UCRL presents both a performance

goal probability and an exceedance probability.

Currently, a DOE Order is being prepared that will define Natural

Phenomena Design Requirements (Draft DOE Order 5480.NPH).

Additionally, a set of Natural Phenomena Standards and Guidance

Documents will be prepared that will establish more explicit requirements

and acceptance criteria for DOE facilities. This set of documents will

supersede UCRL-15910. The new hierarchy of design requirements,

starting with a revised DOE Order 6430.1A, "General Design Criteria," will

provide a clear definition and source of hazard classification as well.

The revised Standard provides further detail on this subject.

13..

EXCLUDING ATTENUATION EXPERT-5

(OR-1, EH-2, RW-4)

Comments were received which questioned the use of LLNL studies which

include LLNL-AE5. Concerns which have been previously expressed by

various sources in regard to the accuracy of LLNL-AE5 are included in the

Standard.

In addition, Figure 7 displays the existing mean EPRI and LLNL (with and

without LLNL-AE5) seismic hazard results and the draft preliminary

revised results from LLNL using a reduced range of ground motion

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