North Indian Bend Wash (NIBW) Superfund Site
View map. The site is designated by the EPA as the area over the plume of contamination.
Superfund Site Background
In 1981, groundwater contaminated from industrial chemicals, primarily trichloroethylene (TCE), was discovered in the southern part of Scottsdale. It is commonly referred to as the North Indian Bend Wash (NIBW) Superfund site.
The area affected is from Chaparral Road to the north, Pima Road to the east, Scottsdale Road to the west, and McKellips Road to the south. In some locations, the groundwater contamination has extended beyond these boundaries and those locations are considered part of the Superfund site.
Once the presence of industrial chemicals was discovered, the city of Scottsdale stopped using these wells for drinking water purposes.
The U.S. Environmental Protection Agency (EPA) identified the parties potentially responsible for causing the contamination and determined that a long-term cleanup effort would be required. The parties potentially responsible for the contamination include —Motorola, Inc.; GlaxoSmithKline (formerly SmithKline Beecham); and SMI Holding LLC (formerly Siemens)—are responsible for all costs associated with the cleanup. The State of Arizona’s Department of Environmental Quality (ADEQ) and Department of Water Resources (ADWR) are overseeing the cleanup for the state.
To clean up the site and drinking water, the potentially responsible parties built the Central Groundwater Treatment Facility (CGTF), located near Pima and Thomas roads. This treatment plant treats water pumped from four groundwater wells that contain TCE.
The CGTF is owned and operated by the city of Scottsdale. Scottsdale ensures that the water produced by the plant meets or surpasses all federal and state standards for safe and healthy drinking water, with oversight from the EPA in cooperation with ADEQ. The facility removes TCE from the water to a level that is considered non-detect (less than 0.5 parts per billion), and is far below the EPA standard of 5 parts per billion.
In 2012, EPA approved the final design for a new treatment facility for the long-term remedy for NIBW site. This facility extracts water from well PCX-1 and uses a Liquid Granular Activated Carbon (GAC) treatment process to clean and treat the water. Construction of the NIBW GAC Treatment Facility (NGTF) for well PCX-1 began in late 2012 and was completed in June 2013. Testing of the new facility began in late June 2013. Previously, water from PCX-1 was treated at the Miller Road Treatment Facility.
During the summer of 2013, a pipeline construction project will connect the NGTF to the City of Scottsdale’s Chaparral Water Treatment Plant. Once the pipeline is connected to the city’s water treatment plant, it will enhance Scottsdale’s water portfolio allowing the city to pump less water from other nearby well. Until the pipeline is completed and when Scottsdale is unable to take the water from PCX-1, the treated water will be discharged into the nearby Arizona Canal.
If you own a home within the Superfund site, you have no liability for the contamination caused by others. Arizona has its own mini-Superfund law which protects innocent homeowners from cleanup liability.
The majority of Arizona's federal Superfund sites involving groundwater contamination are the result of industries disposing of solvents from their manufacturing facilities. In many instances, this water contamination has moved beyond the facilities’ boundaries to the aquifers under residential property.
However, if you are selling a home within the NIBW Superfund site, you must disclose the home is in a Superfund site to potential buyers. Whether disclosure is made by the seller or a real estate agent, the Superfund designation should be disclosed at the first discussion about the property. This will avoid any last-minute questions that could complicate the transaction. If you aren’t sure if your home is within the site, please call 480-312-8743.
For More Information
- Craig Miller, City of Scottsdale Water Resources, 480-312-8743
- Rachel Loftin, US EPA, 415-972-3253 or 800-231-3075
- Wendy Flood, ADEQ, 602-771-4410 or, toll free, at 800-234-5677
- USEPA Region IX Web site
- ADEQ Web site
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