7th Street and Missouri Avenue | Site Overview

Registry placement date: June 24, 2016

Score: 42

County: Maricopa

Location: Phoenix, approximately bounded to the north by East Montebello Avenue, to the south by East Georgia Avenue, to the west by North 6th Street, and to the east by North 10th Street

Contaminants of concern: Chlorinated solvents tetrachloroethene (PCE) and trichloroethene (TCE)  

Action taken: PCE and TCE were initially detected in the late 1990s in groundwater samples taken from several monitoring wells installed to assess a gasoline-range hydrocarbon release from an underground storage tank (UST) system at a convenience store located at the northwest corner of the intersection. In addition, since 1998, PCE has consistently been detected above the Aquifer Water Quality Standard (AWQS) of 5 parts per billion (ppb) in a Salt River Project Agricultural Improvement (SRP) irrigation well, located north of the intersection.

In 2008, ADEQ conducted a soil vapor survey in the area to try to determine the potential source of the PCE and TCE. In 2010, based on the results of the soil vapor survey, ADEQ installed monitoring wells around the Fashion Cleaners facility located northeast of the intersection at 736 East Missouri Ave. In the well immediately downgradient of Fashion Cleaners, PCE has been detected at concentrations ranging from 3.1 to 21 ppb with the most recent sample detecting 8.3 ppb, above the AWQS. In 2016, Fashion Cleaners entered ADEQ's Voluntary Remediation Program to address cleaning up their portion of the contamination.

Groundwater monitoring results suggested that a release of PCE had also occurred from a source generally southwest of the intersection. In 2013, ADEQ installed additional monitoring wells in the area of the former Kino Drapery Cleaners, previously located at 5340 N. 7th Street. PCE was detected at 570 ppb in the monitoring well installed immediately downgradient of the former Kino Drapery Cleaners location. Results from the monitoring well upgradient of the former Kino Drapery Cleaners location indicated no upgradient source of PCE.

In 2014, ADEQ collected soil and soil vapor samples from beneath the building located at the southwest corner of the intersection. Results indicated that a release of PCE had occurred to the subsurface from the former location of Kino Drapery Cleaners.

Community Involvement Activities: A community involvement area has been established and a fact sheet will be mailed to those located in and near the area. For more information or to be included on the mailing list, contact the community involvement coordinator.