Cooper Road and Commerce Avenue | Site Overview

Registry placement date: June 14, 2004

Score: 33

County: Maricopa

Location: Gilbert near Guadalupe Road and Cooper Road, bounded  to the north by Encinas Street, to the south by the Neely Ranch Preserve, to the east by North Golden Key Street and to the west by Horne Street – Dish Drive. 

Contaminants of concern: Tetrachloroethene (PCE) and trichloroethene (TCE) in the groundwater, and PCE, arsenic, chromium, copper, cyanide, mercury and lead in the soil

Action taken: In 2001, groundwater samples collected from a Gilbert monitoring well detected PCE concentrations above the aquifer water quality standard. A Gilbert public supply well is located nearby. Installation of off-site monitor wells began in 2003, and groundwater monitoring has been conducted at the site since March 2005.

ADEQ began an early response action (ERA) evaluation in March 2006 and installed a soil vapor extraction (SVE)/air sparging (AS) and groundwater pump-and-treat remediation system. Start-up of the SVE system occurred in December 2008. Start-up of the AS component occurred in May 2009.

SRP and ADEQ finalized an agreement to discharge treated groundwater to the lateral south of the site in June 2010. The groundwater pump-and-treat system began continuous operations in August 2010 and was discontinued in September 2014.

Status: The final remedial investigation (RI) report was completed in June 2015.

Community Advisory Board (CAB): Established and meets on a regular basis