Purpose - std10240012

DOE-STD-1024-92

Purpose

The purpose of this Standard is to present and implement the fourth objective.

This Standard will address the first three objectives by reference as needed.

This Standard will be operative for about 2 years. The DOE, in cooperation

with the U. S. Nuclear Regulatory Commission (NRC) and EPRI has initiated a

seismic hazard program which is expected to result in more stable seismic

hazard estimates. This work should be completed within 2 years and the

results would be used to develop an updated standard at that time.

This Standard is a revised version of a draft position regarding the LLNL/EPRI

seismic hazard curves (DOE, 1992a) which was reviewed by numerous

organizations. The DOE S WG has prepared a comment/response document which

responds to comments from these organizations. The comment response document

explains the changes made to the draft position and is provided as Appendix A.

Applicability

The Standard explicitly applies to all DOE sites east of the about 104W. The Rocky

Flats site is excluded from the Standard because the LLNL and EPRI studies did not

extend far enough westward to provide the necessary seismic hazard input. The

Paducah, Kentucky site is excluded because this site is in close proximity to the New

Madrid, Missouri seismic zone which should be modeled as an extended line source.

Neither the EPRI nor LLNL studies adequately modeled the New Madrid source in

this fashion. The Paducah site has undertaken appropriate probabilistic seismic

hazard studies including extended source modeling for New Madrid. Department of

Energy sites in the Western United States should be aware of the position,

particularly when developing site-specific probabilistic seismic hazard curves.

Department of Energy sites and facilities that are to be licensed by the NRC are

exempt from this Standard.

Current Department of Energy Orders and Requirements

The design methods currently being used by DOE are contained in UCRL-15910,

"Design and Evaluation Guideline for Department of Energy Facilities Subjected to

Natural Phenomena Hazards", the implementing reference in DOE Order 6430.1A,

the DOE General Design Criteria. UCRL-15910 is based on the use of probabilistic

performance goals for different facility use categories and specifies that the seismic

design basis for DOE nonreactor facilities is to be determined using hazard

exceedance probabilities.

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

Hazards Mitigation (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.

Department of Energy Standard DOE-STD-1020-92, "Natural Phenomena