"I, in fact, have been involved in the construction of and the management of wastewater treatment plants"

Jeff Miller is indicating that he has experience in the wastewater treatment industry. He has been associated with the construction of wastewater treatment plants, along with the management of them. This recommends that he has a deep understanding of the market, and the procedures involved in building and managing wastewater treatment plants. His experience in this field is most likely to be comprehensive, and he is likely to have a mutual understanding of the technical elements of the market. His experience in this field is likely to be important to any company seeking to construct or handle a wastewater treatment plant.