ML16333A094

Current Design Basis Flood Hazards for Use in the MSA

ML16333A094
Person / Time
Site:	Columbia
Issue date:	12/07/2016
From:	Willingham M NRC/NRO/DSEA/RHMB
To:
Willingham M
Shared Package
ML16337A111	List: ML16333A094
References
CAC MF3039
Download: ML16333A094 (5)

Text

Columbia Generating Station Table 1. Current Design Basis Flood Hazards for Use in the MSA1 Mechanism Stillwater Waves/ Design Basis Reference Elevation Runup Hazard Elevation Local Intense Precipitation Not included Not included Not included FHRR Table 3 in DB in DB in DB Streams and Rivers Columbia River2 390.0 ft MSL Minimal 390.0 ft MSL FHRR Table 3 Local Drainage (Combined Effect) 431.1 ft MSL 2.2 ft 433.3 ft MSL FHRR Table 3 Failure of Dams and Onsite Water Control/Storage Structures2 Combined Effect 422.0 ft MSL 2 ft 424.0 ft MSL FHRR Table 3 Storm Surge No Impact No Impact No Impact FHRR Table 3 on the Site on the Site on the Site Identified Identified Identified Seiche No Impact No Impact No Impact FHRR Table 3 on the Site on the Site on the Site Identified Identified Identified Tsunami No Impact No Impact No Impact FHRR Table 3 on the Site on the Site on the Site Identified Identified Identified Ice-Induced Flooding No Impact No Impact No Impact FHRR Table 3 on the Site on the Site on the Site Identified Identified Identified

Columbia Generating Station Table 1. Current Design Basis Flood Hazards for Use in the MSA1 Mechanism Stillwater Waves/ Design Basis Reference Elevation Runup Hazard Elevation Channel Migrations/Diversions No Impact No Impact No Impact FHRR Table 3 on the SIte on the Site on the Site Identified Identified Identified Note 1: Reported values are rounded to the nearest one-tenth of a foot.

Note 2: These hazards remain within the Columbia River Basin, a separate sub-basin away from CGS. CGS is not exposed to these hazards due to intervening topography. This remains true for the re-evaluated hazards.

Columbia Generating Station Table 2. Reevaluated Flood Hazards for Flood-Causing Mechanisms for Use in the MSA1,2 Mechanism Stillwater Waves/ Reevaluated Reference Elevation Runup Hazard Elevation Local Intense Precipitation High point near Radwaste 441.2 ft MSL Minimal 441.2 ft MSL FHRR Table 1 Building truck ramp DG Building Exterior Door (DG2) 440.9 ft MSL Minimal 440.9 ft MSL FHRR Table 1 DG Building Exterior Door (DG1) 440.9 ft MSL Minimal 440.9 ft MSL FHRR Table 1 DG Building Exterior Door 440.9 ft MSL Minimal 440.9 ft MSL FHRR Table 1 (HPCS DG)

Reactor Building railroad bay 441.1 ft MSL Minimal 441.1 ft MSL FHRR Table 1 door Service Water B pump house 441.0 ft MSL Minimal 441.0 ft MSL FHRR Table 1 personnel door Service Water B spray pond wall 435.2 ft MSL Minimal 435.2 ft MSL FHRR Table 1 Service Water A pump house 439.0 ft MSL Minimal 439.0 ft MSL FHRR Table 1 personnel door Service Water A spray pond wall 435.1 ft MSL Minimal 435.1 ft MSL FHRR Table 1 Roof drain (storm sewer) header 440.3 ft MSL Minimal 440.3 ft MSL FHRR Table 1 manhole MH-S5 Vehicle Barrier System high point 438.0 ft MSL Minimal 438.0 ft MSL FHRR Table 1

Columbia Generating Station Table 2. Reevaluated Flood Hazards for Flood-Causing Mechanisms for Use in the MSA1,2 Mechanism Stillwater Waves/ Reevaluated Reference Elevation Runup Hazard Elevation Benchmark infront of TSC 440.6 ft MSL Minimal 440.6 ft MSL FHRR Table 1 entrance Benchmark in by NW remote air 441.0 ft MSL Minimal 441.0 ft MSL FHRR Table 1 intake Benchmark infront of GSB 440.9 ft MSL Minimal 440.9 ft MSL FHRR Table 1 entrance Benchmark infront of Building 88 440.6 ft MSL Minimal 440.6 ft MSL FHRR Table 1 North Side of Flex Building 82 440.6 ft MSL Minimal 440.6 ft MSL FHRR Table 1 North Side of Flex Building 600 437.8 ft MSL Minimal 437.8 ft MSL FHRR Table 1 South Side of Flex Building 600 438.0 ft MSL Minimal 438.0 ft MSL FHRR Table 1 ISFSI Pad (North) 443.3 ft MSL Minimal 443.3 ft MSL FHRR Table 1 ISFSI Pad (South) 443.3 ft MSL Minimal 443.3 ft MSL FHRR Table 1 Facilities Fuel Station 440.6 ft MSL Minimal 440.6 ft MSL FHRR Table 1 Diesel Generator Tank Access 442.1 ft MSL Minimal 442.1 ft MSL FHRR Table 1 Flex Gasoline Storgae Module 440.8 ft MSL Minimal 440.8 ft MSL FHRR Table 1

Columbia Generating Station Table 2. Reevaluated Flood Hazards for Flood-Causing Mechanisms for Use in the MSA1,2 Mechanism Stillwater Waves/ Reevaluated Reference Elevation Runup Hazard Elevation Streams and Rivers Local Drainage 432.0 ft MSL Minimal 432.0 ft MSL FHRR Table 3 Note 1: Reevaluated hazard mechanisms bounded by the current design basis (see Table 1) are not included in this table Note 2: Reported values are rounded to the nearest one-tenth of a foot.