Question II (3.0%): A geomembrane-lined surface impoundment had been constructed without performing an advanced ground survey (i.e. soil underground geology analysis and characterization). After this impoundment started the operation, it was recognized that there happens a gas generation due to biodegradation of the organic clay layer existing under the impoundment as shown in Figure below. The areal extent of the impoundment is 500 m by 500 m and having a depth of 10 m. The base of the impoundment was designed and constructed as two adjacent geosynthetic layers including a layer of geomembrane underlain by a layer of geotextile. This configuration of the composite layered system designed for the base of the impoundment results in flow of the generated gas that is distributed evenly on all directions along the base below the composite multi-layered system, and then, rising up through side slopes as shown in Figure. In this way, an even and equal distribution of the generated gas appears. It was measured that a gas generation of 0.005 m³ per day, per unit area of 1 m² at a pressure of 10 kPa occurs. The density of the generated gas has been determined as 0.01 kN/m³. For the project, a needle punched nonwoven geotextile having a mass per unit area of 550 g/m² was selected and employed in the field for which the allowable transmissivity is 31.25 m³/day-m² at a normal stress 100 kPa and a gas pressure of 10 kPa. In light of the information provided herein, Calculate: (a) [10% ] The flow rate of the generated gas, (b) [10%] The gradient of the generated gas at a pressure of 10 kPa, (c) [5%] The transmissivity of the generated gas, The factor of safety of this geotextile's transmissivity for this set of the (d) [5%] conditions given in the problem. Geomembrane Geotextile Liquid 10 m Sand 2 m Organic Clay Sandy Gravel 12 m 6 m