The following hydrologic events which are potential sources of flooding

DOE-STD-1023-95

A3.3.2-d.

The following hydrologic events which are potential sources of flooding shall be included in the

flood hazard analysis:

( 1)

River flooding

( 2)

Levee or dam failure

( 3)

Flood runoff/drainage

( 4)

Tsunami

( 5)

Seiche

( 6)

Storm surge

( 7)

Wave and runups

( 8)

( 9)

Water-carried debris

(10)

Mud flows

For each of these potential sources of flooding, appropriate information on topography,

meteorological conditions, results of existing flood analyses, stage-discharge data, etc., that are

necessary to determine and analyze the source shall be collected as specified by DOE-STD-

1022-94.

The flood screening analyses shall determine potential flooding due to multiple sources and

other possible chains of events.

For each of the sources of potential flooding, simple criteria (without performing any analysis

other than those collected) shall be provided establishing whether the site is affected by

potential flooding from this source. These criteria include the applicable physical arguments

that certain sources not present are very unlikely or that their consequences on the site are

negligible or nil.

For the sources of flooding for which no clear basis has been established to discard them as

potential flood hazards to the site, a preliminary flood hazard analysis shall be performed.

A preliminary flood hazard analysis is performed for all sources of flooding identified as

having potential impacts on the site. This analysis shall provide a measure of the magnitude

and probability of occurrence of extreme events. This analysis does not need to be

comprehensive and can be based on existing studies. For example, it is sufficient to use flood

insurance studies or equivalent, that estimate flood probability to 2x10-3 to measure the

magnitude and probability of occurrence of river flooding, and extend these results to a lower

A-10