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The project site is located on the east banks of Redwood Creek,approximately one half mile west of the mouth of Redwood Creek. This natural deepwater channel is surrounded by extensive areas of marshlands and associated Bay Mud deposits. Bay Mud sediments, formed during thousands of years of deposition,are primarily composed of gray to black unconsolidated silty clay with lenses of sand,peat and shell fragments. Bay Mud is known to be susceptible to liquefaction(failure of saturated earth materials when subjected to shaking). Soft sediments,like the unconsolidated alluvium and soft sediments along the baylands,can amplify seismic waves and intensify ground shaking.Earthquake ground shaking can lead to secondary ground failures caused by liquefaction. Liquefaction causes saturated soils to lose strength and the building overlying them to suffer considerable damage.The project site is located within a very high risk area for liquefaction according to the Association of Bay Area Governments(ABAG,2009b).There are potential slope stability hazards associated with the riprap slope of the Multi-Agency Maritime Facility. Under static or dynamic(earthquake conditions) forces,this slope could become unstable but it would not result in exposure of people or structures to substantial loss,injury or death. a.iv) The project site is located on relatively level topography.No impact associated with landslides would occur. b) No extensive backfilling,grading and compaction of soil is required for construction of the project. The project would not expose areas of loose soil that,if not properly stabilized,could be subjected to soil loss and erosion by wind and storm water runoff. c-d) Settlement is a potential hazard associated with placement of new loading such as a structure. Settlement of the ground surface can be accelerated and accentuated by earthquakes. During an earthquake,settlement can occur as a result of the relatively rapid compaction and settling of subsurface materials(particularly loose,uncompacted, and variable sandy sediments above the water table)due to the rearrangement of soil particles during prolonged ground shaking. Settlement can occur both uniformly and differentially(i.e.,where adjoining areas settle at different amounts),also referred to as differential settlement.Areas underlain by artificial fill or soft bay mud,like the proposed project, would be susceptible to this type of settlement. Expansive soils possess a"shrink-swell"behavior which is the cyclic change in volume(expansion and contraction)that occurs in fine-grained clay sediments from the process of wetting and drying. Structural damage may occur over a long period of time,usually the result of inadequate soil and foundation engineering or the placement of structures directly on expansive soils.The proposed project does not require foundational piles located in saturated sediments and would not be subject to the effects of expansive soils. e) The wll not require septic tanks or alternative wastewater disposal systems and the project will have no impact from such conditions. References Association of Bay Area Governments(ABAG), 2009a. ABAG Shaking Intensity Maps and Information, San Andreas and Hayward Fault Shaking Scenarios. http://quake.abag.ca.gov/mapsba.html; accessed January 2010 Association of Bay Area Governments(ABAG),2009b. ABAG Shaking Intensity Maps and Information, San Andreas and Hayward Fault Liquefaction Scenarios. http://www.abag.ca.gov/bayarea/eqmaps/liquefac/liquefac.html;accessed January 2010 Port of Redwood City Multi-Agency Maritime Facility 26 February 2010 Initial Study