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j) Redwood Creek Channel is in a"Tsunami Inundation Area"and a high-intensity ground shaking area,as defined by the California Emergency Management Agency,Coastal Region(ABAG 2010). Tsunamis and seiches are waves generated in bodies of water usually by seismic events. Tsunamis are large ocean waves caused by underwater earthquakes or volcanic eruptions. Seiches are stationary waves associated with semi- enclosed bodies of water,usually caused by strong winds and/or changes in barometric pressure. Although the project is located within such potential hazard areas,it does not propose land-side structures that would be inhabited by people. As a result,no people would be exposed to the risk of loss,injury or death involving a seiche or tsunami-related seismic event. A mudflow is a large,rapidly moving(up to 50 miles per hour)mass of mud formed by loose earth and water. Hillsides and slopes of unconsolidated material could be at risk to mudflows if these areas become saturated. Usually,a mudflow occurs as a result of a dual condition of loss of brush cover and the subsequent accumulation of water on the ground,preceded by a period of heavy or sustained rainfall. Given the geography and physical characteristics of the project area,notwithstanding a long-term rise in sea(Bay) levels,there is no reasonable expectation of a mudflow to occur at the project site. k—p) The Multi-Agency Maritime Facility construction would result in a net reduction of landside disturbance (abutment)from approximately 81 square feet to 36 square feet. Project construction would also occur during the typical"dry season"between June and October. As such,the project would not result in significant construction or post-construction erosion, sedimentation,or hydro-modification of the area. This would not result in an increase in impervious surface area over that which currently exists at the project site. Material common to construction, such as fuels and petroleum products would be in such small quantities that it would pose no significant hazard or risk to the public or the environment. The use,clean up,and disposal of potentially hazardous material will be managed according to standard procedures to protect air quality, water quality,and the environment as per state laws. The adjacent dirt area just north of the ramp,or the bare area between the railroad tracks,would be used for materials and equipment staging, and construction vehicle parking.The potential for discharge of stormwater pollutants would be minimized by construction scheduling during the June-October"dry season"and the standard BMPs (Stormwater Quality Task Force, 1993)used at construction sites to eliminate and contain potentially toxic and hazardous materials discharge to Redwood Creek. References Association of Bay Area Governments(ABAG).January 11,2010.Tsunami Inundation Emergency Planning Map for the San Francisco Bay Area, www.abag.ca.gov/bayarea/egmaps/tsunami/tsunami.html,accessed February 18,2010. City of Redwood City, Strategic General Plan, Public Safety Element,January 22, 1990,as amended. San Francisco Bay Regional Water Quality Control Board.Water Quality Control Plan for the San Francisco Bay Basin.January 18. 2007. http://www.swrcb.ca.gov/rwgcb2/basin planning.shtml,accessed February 18,2010. Stormwater Quality Task Force. 1993. California Storm Water Best Management Practice Handbook-Construction. www.coastal.ca.gov/la/doc, accessed February 18,2010 Port of Redwood City Multi-Agency Maritime Facility 32 February 2010 Initial Study