A laboratory column of 10 cm2 cross-sectional area is 1 m long. Porosity is 0.25 and influent flow rate is 8 L/day. Particle grain size is 0.5 mm. At time t=0, injection of a nonsorbing contaminant into the influent at a constant concentration of 10 mg/L is started. Estimate the contaminant concentration as a function of the time at the outflow (show both the equation and the concentration-time plot by using Excel or other similar tools).