Reducing Arsenic Concentrations in Illinois

AdEdge Technologies, Inc. was selected in 2007 by the U.S. Environmental Protection Agency (EPA) and the host site in Round 2a Arsenic Demonstration Program to implement a turnkey arsenic treatment for the Geneseo Hills Community in Geneseo, Ill.

The Geneseo Hills water system is served by one well with a design flow of 200 gal per minute, with a backup well. The well provides potable water for a community with 190 connections and a population of approximately 480 residents.

The treatment system receives water on the demand side of the storage tanks with an arsenic level of 25 parts per billion (ppb), higher than the EPA maximum contaminant level (MCL) of 10 ppb. From the combined 21,000-gal twin pressurized storage tanks, water is treated by the system, which is configured in parallel. AdEdge was contracted by EPA to provide and manage all permitting with IEPA, design, fabrication, installation and start-up activities.

The company proposed and installed an APU-5460CS-S-2-AVH treatment system , designed to reduce arsenic concentrations to below the new arsenic treatment standard of 10 ppb. The system uses adsorption technology, deploying the company’s Bayoxide E33 granular ferric oxide media. The design also includes a 100% backwash recycle system capable of filtering particulates and reclaiming all of the periodic backwash water for treatment and use.

The packaged system features twin, 54-in.-diameter carbon steel adsorption vessels mounted on a painted epoxy-coated carbon steel skid, pre-piped and integrated. The system is placed after a prechlorination module for oxidation of As (III) to As (V) and is equipped with automated control valves and harness, central control panel with programmable logic controller (PLC) and a color user interface screen. The system also features a hydraulic panel with local gauges and sample ports for a complete functioning packaged unit.

Since full-time operation began in April 2008, the system has reduced arsenic consistently below 2 ppb, well below the MCL. Approximately 30,000 gal per day is being processed through the system on average.

The site’s operator performs the routine sample collection and reporting associated with the EPA’s Demonstration Program requirements, with quarterly reporting of the data by EPA’s contractor, Battelle.