During the conceptual design stage of Problem 1-1, the design firm identifies the need f...

During the conceptual design stage of Problem 1-1, the design firm identifies the need for iron removal that was not anticipated in the screening of alternatives. The capital cost for each of the membrane alternatives is now estimated to be an additional $500,000. Is the Membrane A alternative still the best choice? Use the interest rate and design life from Problem 1-1.

Problem 1-1.

At the end of the preliminary design-stage of a small water treatment system design, the following three options remain feasible. The consulting firm uses an interest rate of 6.00% and a design life of 20 years for project evaluation. Based on cost, which alternative should the engineering firm recommend?