Minneapolis: LeJeune Ryder vapor intrusion site

LeJeune-Ryder Student Transport is a Superfund site located immediately north of the intersection of 60th Street West and Pillsbury Avenue in Minneapolis. In the 1990s, contamination from a commonly used solvent, tetrachloroethene (PCE), was discovered on the property formerly occupied by the school bus company Ryder Student Transport.  The site was used later by LeJeune Building Company and has since changed hands.  

Environmental testing discovered that contamination had reached the groundwater and moved off the property to the south. Cleanup work began on the site in 2007 with the installation of a soil vapor extraction system (SVE) to address the soil and groundwater contamination. The SVE ran until 2010 when cleanup goals were met.  More recently, additional environmental testing was completed to look for PCE in the air in the soil — this is called soil vapor. This series of testing found that PCE was present in the test sample locations taken off-site of the property.

Since the time of the initial cleanup, more is known about PCE and its potential health effects. The main concern is that PCE in soil vapor could make its way into buildings through cracks and openings in the building foundation impacting indoor air; this is called vapor intrusion. Additional testing to check homes near this site for vapor intrusion is planned.

Map: Area of concern

This map shows the current portion of this Minneapolis neighborhood involved in testing.

Map of Minneapolis neighborhood with area of concern

Soil vapor sampling

In December 2014, soil vapor samples were collected in the public right-of-way next to five residential properties and by the source of the contamination on 60th Street West by an environmental company working for LeJeune Investments, Inc. The residential properties are located both southeast and north of the LeJeune Ryder property. All of the samples exceeded the vapor intrusion screening values for PCE which is 20 micrograms per cubic meter (µg/m3).

Based on an evaluation of the vapor intrusion data, MPCA has asked LeJeune Investment, Inc. to conduct a more extensive, building specific vapor intrusion assessment in the neighborhood. The planned investigation includes collecting sub-slab vapor samples from the residential buildings in addition to collecting soil vapor samples in the public rights-of-way.

Sub-slab sampling and vapor venting system installations

With the owner’s permission, a sample of the air under the building foundation will be collected, this is called sub-slab sampling. If the sampling results exceed screening levels, a vapor venting system will be installed at no cost.  The vapor venting system will improve the air quality in your home by preventing PCE vapors from entering through potential passageways in the building’s foundation.

Timeline

Time period Activity
February 2016 Obtain access from property owners.
March 2016 Sample homes and businesses in the vapor intrusion area of concern. Conduct additional soil gas testing in city right of ways.

Contact info

For more information about remediation activities at the LeJeune-Ryder Student Transport Site, contact MPCA project manager Pam Foster at 651-757-2778 or pamela.foster@state.mn.us.  

For information about health issues related to this site, contact Daniel Pena of the Minnesota Department of Health at 651-201-4920 or daniel.pena@state.mn.us.