Level of Review

DOE-STD-1023-95

Number of

Zonation

Recurrence

occurrences

Upper

bound

cutoff

Fault

Area A

300-

Site

500 km

0.1

0.01

Area B

Magnitude

300-500 km

(186-311 mi)

Frequency of

Ground

Seismic hazard

exceeding ground

motion

curve calculation

Attenuation

motion level (per yr)

level

10-1

10-2

10-3

Attenuation

curve for

magnitude m

10-4

0.1

0.5

1.0

Distance

Ground Motion Level

Shaded area = P(PGA > glm,r)

Figure 3.1 Four Steps in Probabilistic Seismic Hazard Analysis

(3)

Characterization of Uncertainty in Parameters of the Hazard Model - The PSHA shall

accommodate random variability in location, size, and ground motions associated with future

earthquakes as well as uncertainties related to the lack of knowledge of the models and

parameters that characterize the hazard.

(4)

Quantifying Uncertainty - Two approaches are acceptable for characterizing and quantifying

uncertainties in PSHA: elicitation of multiple experts and peer review (the approaches can be

used separately or together). Proper documentation of the technical basis for all assessments is

an essential element.

3.1.2.3 Level of Review

The SSHAC (1997) report provides guidance on completion of independent reviews. The credibility

and defensibility of a modern PSHA depends on the quality of the input as well as the completeness

of the documentation. All the information, input, and analysis should be fully documented and

independently reviewed. The independent review should focus on the arguments and logic used to

develop the hazard results. The review team should include personnel with expertise in the seismic