Silverbell Landfill | WQARF Site

Silverbell Landfill vapor extraction system

Silverbell Landfill | Site Overview

Registry placement date: April 23, 1999

Score: 51

County: Pima

Location: 3200 North Silverbell Road in northwest Tucson, approximately bounded by Sweetwater Drive on the north, Grant Road/Ironwood Hills Drive on the south, Interstate 10 on the east and Silverbell Road on the west and comprised of approximately 40 acres

Contaminants of concern: Tetrachloroethene (PCE), trichloroethene (TCE), cis-1,2-dichloroethene (cis-1,2-DCE) and vinyl chloride

Action taken: In 2001, the city of Tucson (COT) began operation of a full-scale soil vapor extraction (SVE) system to remove and treat contaminated volatile organic chemical (VOC) landfill gases contributing to the groundwater contamination. From December 2006 until 2008, the system operated intermittently to control methane migration. In April 2008, the system was shut down and the equipment was removed, but COT conducts soil-gas rebound testing periodically.

In 2010, COT proposed to install a pump-and-treat (P+T) system to address the site groundwater plume. Since 2010, COT has been working on revisions (including conducting additional modeling) to this proposal.

Status: COT identified a contractor to design, build and operate the groundwater P+T system. However, the initial design had to be modified after COT decided that the treatment plant could not be located on the Silverbell golf course. A revised design is now complete and construction of the P+T system is scheduled to begin in early October 2018 and startup of the system in Spring 2019.

Community Advisory Board (CAB): Not applicable under “old WQARF” laws/rules.