I work in a community that has several dozen polluting light industrial businesses mixed in with homes, schools, and churches. We are four years into a specific plan process and have entered into environmental review. The specific plan will completely rezone the neighborhood, with the aim of revitalizing and densifying for residential and residential-compatible land uses. However, the City has decided that they would like to create a "clean industrial" designation that would allow light industrial businesses to stay in the neighborhood by right or with a CUP if they are not polluters and do not have significant adverse impacts on the neighborhood. They have yet to decide how the zoning will treat these light industrial uses.
My question is this: What are the different options for establishing zones that prohibit problematic businesses, and yet still allow for this exemption? How do you define which light industrial businesses should be permitted in a way that the planning department can realistically enforce it at their front desk?