The senior design section (CEE 4905) advised by Dr. David Hand and Dr. Eric Seagren traveled on February 1, 2019, to visit the Plainfield Township Water Department’s treatment plant outside of Grand Rapids, Michigan. The plant is operating a pilot-scale study examining the removal of per- and poly-fluoralkyl substances (PFAS) from their water supply using granular activated carbon (GAC). PFAS compounds were invented in the 1930s and since then have been manufactured for a variety of uses including: nonstick coatings, stain and water-resistant products, protective coatings, and firefighting foam. These compounds are very stable in water, are persistent, bioaccumulative, and not known to degrade in the environment. In 2017, Michigan was one of first states in the country to begin to establish a clean-up standard for PFAS in groundwater when used as a drinking water source. The Michigan PFAS Action Response Team, made up of several state agencies, has worked to identify PFAS contamination in the state.
The purpose of this senior design project is to develop design guidance for the use of GAC for the removal of PFAS chemicals from water supplies. GAC is a Best Available Technology (BAT) as designated by the USEPA for removal of organic chemicals from water. In fact, GAC is presently being used in several of the sites identified in Michigan for removal of PFAS compounds. Design guidance for using GAC for the removal of these compounds is needed as it can provide regulatory agencies, consulting engineers, and water utilities with the tools necessary to effectively and economically evaluate the use of GAC for treatment of these chemicals. Therefore, the main objectives of this project are to: (1) evaluate the design of the pilot-scale GAC system that has been implemented at the Plainfield Township Water Department’s treatment plant, and (2) to develop a general design guidance for the application of GAC fixed-bed adsorption processes for the removal of PFAS from drinking water.