Jump to main content or area navigation.

Contact Pacific Southwest Waste Program

Pacific Southwest, Region 9

Serving: Arizona, California, Hawaii, Nevada, Pacific Islands, Tribal Nations

Evoqua Water Technologies
(formerly Siemens Carbon Regeneration Facility)


Facility Summary

Evoqua Water Technologies, formerly known as Siemens or US Filter Westates, is a carbon regeneration facility located on the Colorado River Indian Tribes (CRIT) Reservation near Parker, AZ. Evoqua treats spent carbon in a regeneration furnace to purify it and make it a salable product. Evoqua receives over 5,000 tons of spent carbon from 30 - 35 states across the United States. About 11% of this spent carbon is considered hazardous waste and is regulated by US EPA.

Evoqua Regulatory History

The US EPA is responsible under the Resource Conservation and Recovery Act (RCRA) for permitting facilities that manage RCRA-regulated hazardous wastes on tribal lands. US EPA first began regulating carbon regeneration furnaces in 1991. Several facilities were already operating or had begun construction on carbon regeneration furnaces, including Evoqua (then known as US Filter Westates). These existing facilities were granted “interim status” to operate under the hazardous waste provisions of RCRA subtitle C, while applying for a final RCRA hazardous waste permit. Evoqua was granted interim status in 1992, requiring them to comply with EPA regulations to operate safely.

Evoqua submitted their original permit application in 1995. US EPA reviewed their permit application, issued comments and requested additional information. Evoqua submitted a revised application in February 2003, with US EPA responding with additional comments and requesting additional information in 2005. Evoqua responded to the US EPA comments and resubmitted the revised application in 2007. CRIT, the landowner, signed as co-applicant on the permit application on December 14, 2009. This restarted the permit application review, which had been on standby until the CRIT signature was received.

Current Status

US EPA submitted comments on the Part B application to the Evoqua facility in September 2011, and comments on the Closure Plans and the Financial Assurance mechanism in December 2011. Evoqua revised the Part B application to incorporate both sets of US EPA’s comments, and submitted the revised Part B to US EPA on April 26th, 2012. US EPA requested more information on May 15, 2014 and Evoqua revised parts of the Part B application and submitted it on July 22, 2014.

After US EPA staff reviews the revised permit application, the Agency will determine if the permit application is complete and technically adequate. EPA will then make a proposed decision on whether to deny or grant the permit and open a 45 day Public Comment Period. Since about 11% of the spent carbon coming into Evoqua is considered RCRA hazardous waste, Evoqua can still continue to operate and regenerate the 89% non-hazardous carbon even if US EPA denies their RCRA permit.

Community Involvement

US EPA would like to hear from you throughout the review of Evoqua's permit application. EPA will hold a public meeting in Parker leading up to the draft permit decision. At this public meeting, EPA will provide information about Evoqua and respond to community questions and concerns. EPA will also schedule a formal public hearing when the agency issues a public notice detailing the draft permit decision.

Evoqua Contact Information

Top of page

Jump to main content.