In January 2007, customers of Valle Verde, located east of Interstate 19, were informed by the water company of the detection of tetrachloroethylene (PCE), an industrial solvent, at concentrations above the maximum contaminant level of 5 micrograms per liter in samples collected from Wells 1, 2, 4 and 7 in Valle Verde’s system.

As a result, alternate drinking water supplies were provided. ADEQ has been working with Valle Verde and the City of Nogales since that time to address the PCE contamination and establish a permanent solution for the water supply problem.

“We are committed to implementing a long-term solution to the PCE contamination so that residents in the area are assured of safe and reliable drinking water,” Director Owens said. “We are making a substantial commitment of resources to address this problem.”

The WQARF funding will be used for construction and operation expenses for a granular activated carbon (GAC) treatment system at site of Valle Verde Well #2. The system will consist of two GAC contact vessels where contaminated water will flow through and PCE will be absorbed by the carbon. Storage tanks also will be constructed at Valle Verde Wells #2 and #3 to aid in distribution of treated water. The construction is expected to take about one year.

In addition to construction of the water treatment system, ADEQ is working with Valle Verde and the City of Nogales to construct a pipeline connection between their two systems which could be used by Valle Verde during potential future water supply emergencies. Such interconnection agreements are common between neighboring water supply systems.

Contact:
Mark Shaffer
Director of Communications
(602) 771-2215