A 10-m long (into the page) sheet pile wall has been partially installed through a silty sand layer as shown in the figure below. The depth of the embedded sheet pile wall is 9 m below the ground surface. The water level at the upstream and downstream side of the sheet pile wall is 16 m and 0 m above the ground surface, respectively. The silty sand layer has a thickness of 18.5 m, and a hydraulic conductivity of 7 10 cm/sec. The silty sand is underlain by impermeable bedrock. 18.5 7sat=20.0 kN/m 9m Determine the factor of safety against a quick condition. 16m Datum (Not to scale)