The 55th and Lyndale Avenue South vapor site in Minneapolis is comprised of two adjacent properties that included a former dry-cleaning operation. The site was referred to MPCA in 1999 by a property owner working on a property transfer. An investigation of a petroleum release at a nearby site in 2010 revealed perchloroethlyene (PCE) in groundwater and soil vapor near the original site. It is likely that the contamination may be coming from more than one property.
What's the problem?
In 2012, an MPCA investigation looked for sources of PCE contamination and tested for underground soil vapor. The investigation identified the former dry-cleaning site, and began defining the area of contamination.
The soil vapor investigation continued in 2013 and 2014 and revealed the possibility of vapor intrusion at several nearby homes and businesses. A mitigation system was installed in the office area of a nearby commercial building. This action was completed in 2014 in response to soil vapors exceeding 100 times the industrial indoor air standard underneath the commercial building.
The work to define the area of contamination and buildings for vapor intrusion is ongoing. The MPCA has installed vapor intrusion mitigation systems in five homes and two commercial buildings. The agency is working on installing a mitigation system in one other home.
The agency would like to conduct sub-slab sampling at four additional commercial properties and 17 homes. In August 2016, the MPCA will be sending access agreement letters to residents and business owners of properties where the agency would like to do this sampling.
Possible health effects
Vapor intrusion occurs when chemical vapors seep from contaminated groundwater through the soil and into buildings. The chemicals can then contaminate indoor air.
Health effects can occur when people breathe high concentrations of PCE vapors in the air over many years.
- Exposure can result mainly in effects like vision changes, delayed reaction time and reduced mental function. These symptoms usually go away after exposure stops.
- PCE may cause cancer based on human studies. The studies suggest there may be an increase in bladder cancer, non-Hodgkin’s lymphoma, and multiple myeloma. PCE exposure to rodents also increases liver tumors and leukemias.
The potential for a person to actually experience a health effect depends on the amount of a chemical that a person is exposed to and the length of the exposure. Exposures to chemicals for most people are likely to be at low levels for part of a day, or part of a year, etc.; these exposures are unlikely to be associated with health effects.
Site Remediation and Redevelopment Section