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EPA in Arizona

Evoqua Water Technologies LLC

Evoqua Water Technologies LLC (Evoqua) operates a carbon regeneration facility located on the Colorado River Indian Tribes (CRIT) Reservation near Parker, Arizona. (See below boxes for a map and a description of Evoqua's process). Evoqua annually receives over 5,000 tons of spent carbon from across the United States. About 11% of this spent carbon is considered hazardous waste and is regulated by EPA under the Resource Conservation and Recovery Act (RCRA)

Pursuant to RCRA, EPA is responsible for permitting facilities that manage RCRA-regulated hazardous wastes on tribal lands. In 1991, EPA required carbon regenera­tion furnaces to obtain hazardous waste permits. At that time, the Evoqua facility (then known as US Filter/Westates) was already undergoing construction of a carbon regeneration furnace which meant it was eligible to operate under “interim status” RCRA regulations while applying for a RCRA hazardous waste permit. 

The facility is also regulated under other federal environmental statutes such as the Clean Air Act and the Emergency Planning and Community Right to Know Act.

September 2018 EPA Permit Decision

On September 25, 2018, EPA made a Final Permit Decision (see Announcement of Permit Decision) to issue a RCRA Permit to Evoqua Water Technologies LLC and CRIT, for the facility located on the CRIT Reservation near Parker, Arizona.

Click to View Map of Evoqua

Evoqua Water Technologies LLC

What is "Carbon Regeneration"?

Activated carbon is a granular material used in air and water filtering systems to remove contaminants. Over time, activated carbon loses its ability to capture contaminants, resulting in "spent" carbon. At Evoqua, spent carbon is heated to high temperatures in a "carbon regeneration" furnace. This process removes most of the contaminants and reactivates the carbon, which can then be sold as a commercial product to be reused in filtering systems.

Other Names

Evoqua Water Technologies has previously been known as Siemens, US Filter, and Westates. The facility is now referred to as Evoqua, but the prior names remain in older documents attached to this web page.