1.A flocculation/sedimentation combination basin in a conventional drinking water treatment plant is to be constructed of cast-in-place reinforced concrete. The horizontal flow rectangular basin will be located in New Jersey, USA. The client must decide whether or not to pay to have the basins covered with a concrete slab or,alternatively, left open. Discuss all the factors that the client should consider when deciding whether or not to cover the floc/sed basin. Discuss all the advantages, disadvantages and considerations that the client should think about. Be clear and complete so the client understands what the choices are and any ramifications of the decision.
2.If the sedimentation basin in problem 1 (ignore the floc basin for this problem) receives a flow of 1400 gallons per minute, and has a depth of 10 feet, what are the length and width dimensions if the basin is designed to remove particles that have a settling velocity greater than 30 feet per day? The basin will have a length to width ratio of 4 to 1. What are the flow through velocity and hydraulic retention time for this basin?