Vapor Intrusion
Vapor Intrusion Fact Sheet (PDF)
What is vapor intrusion?
Vapor intrusion occurs when vapors (gases) from volatile organic chemicals (VOCs) in contaminated soil and/or groundwater move through soil and into outdoor air and homes/buildings through cracks in floors, walls, and gaps around pipes. In outdoor air, these vapors are diluted to harmless levels. When trapped in an enclosed space like a home or building, these vapors can collect and impact the indoor air quality and pose a risk to health.
What are the symptoms of vapor intrusion exposure?
Symptoms of exposure to chemical vapors may include:
- Eye irritation
- Respiratory irritation
- Headaches
- Nausea
What are the health effects of vapor intrusion?
Having VOCs in your air does not mean adverse health effects will occur. Virtually everyone is exposed to VOCs on a regular basis. Health effects of vapor intrusion will vary based on the type of chemicals, the levels of the chemicals found, the length of exposure and the health of exposed individuals. Chemicals affect people in different ways. Low-level chemical exposures over many years may raise the long-term risk of cancer or chronic disease. Environmental cleanup guidelines are set at very low levels to protect even the most sensitive people from potential future health effects.
How do I know if there is vapor intrusion in my home?
Homes/buildings built on land that may have been contaminated by hazardous substances or pollutants are more at risk for vapor intrusion. Professional sampling of soil, groundwater, soil gas, and indoor air at and around your home can identify the extent of vapor intrusion occurring.
Can vapors in my home come from household sources?
Some examples of products containing VOCs include: paints and lacquers, paint strippers, cleaning supplies, pesticides, gasoline and other fuels, building materials and furnishings, office equipment such as copiers and printers, correction fluids and carbonless copy paper, graphics and craft materials including glues and adhesives, permanent markers, and photographic solutions. VOCs are also present in cigarette smoke and motor vehicle exhaust. Common sources of VOCs found at environmental cleanup sites include gasoline and other petroleum compounds, dry-cleaning chemicals, and industrial solvents used for degreasing.
What can I do about vapor intrusion?
- Apply an impermeable barrier to dirt floors in basements/crawlspaces
- Seal cracks and openings in foundation walls/floors and around gaps for pipes
- Install a mitigation system (radon mitigation systems work to reduce vapor intrusion)
- Building over-pressurization (adjusting HVAC system to increase indoor air pressure)
Where can I find more information about vapor intrusion?
Visit the Michigan Department of Environmental Quality (MDEQ) website for more information.
Additional Info
MDEQ has an ongoing, statewide effort to investigate indoor air quality resulting from known contamination sites. Site contamination is identified in many ways, sometimes from a Baseline Environmental Assessment (BEA). A BEA is an evaluation of environmental conditions at a property prior to being purchased and focuses on detecting the presence of hazardous substances.
The Franklin Village Plaza was the site of a BEA. When the property was purchased in 2010, soil and groundwater sampling was conducted and elevated levels of chemicals were discovered. The BEA was submitted to the MDEQ in January 2011. This prompted MDEQ to begin additional testing to determine if risks to human health and the environment are present.
The 2011 BEA indicated that the chemicals Trichloroethylene (TCE) and Tetrachloroethylene (PCE) were likely present at the property. TCE and PCE are commonly used in dry cleaning and metal degreasing.
The BEA specified that TCE and PCE were likely present due to a previous dry cleaner and gas station that were on the property in the 1930s - 1970s. The current dry cleaner currently located in the plaza did not release these chemicals and does not conduct dry cleaning or store chemicals onsite.
Chemicals released in the environment can move through soil and groundwater. Some chemicals, such as TCE and PCE, easily evaporate and become a vapor in the air. These vapors can enter buildings and pose a risk to occupants. Samples of air inside buildings and below the ground can be collected and analyzed to determine if risks to human health and the environment are present.
After site access is secured from the property owner, the MDEQ may complete the following, including but not limited to:
- Set a sampling schedule with property owners
- Determine the locations of soil borings, monitoring wells, and vapor points/pins
- Schedule drillers and other contractors
- Review sampling and health and safety plans
- Notify affected stakeholders and local authorities of the project
- Complete a subsurface contaminant survey and review the results
- Complete soil borings, monitoring well installation, and vapor point installation
- Collect soil samples, groundwater samples, and vapor samples
- Receive and evaluate soil, groundwater, and vapor sample results
- Collect and evaluate indoor air samples at property
- If needed, expand the scope of the project/investigation based on those results
- If needed, request water supply sampling be conducted by the local health department
See the What is Vapor Intrusion brochure for detailed steps.
Testing recently began at Franklin Village Plaza. Testing will continue until the areas where risks from the chemicals are identified and measures are taken to assure protection of the public’s health and safety. MDEQ will collect groundwater and subsurface vapor samples approximately every 3 months for at least 1 year.
A temporary and voluntarily evacuation of a home or business may be recommended by Oakland County Health Division (OCHD) due to an associated risk to human and environmental health.
OCHD may determine a mandatory evacuation is needed if an imminent danger exists.
See the What is Vapor Intrusion brochure for detailed steps. Response activities to manage and reduce risks may be done to keep potentially harmful vapors out of indoor air. Other activities to remove or treat contaminated soil, soil gas, and groundwater may also be done.
The sampling, mitigation and remediation efforts are funded by MDEQ using public funds appropriated by the legislature. Remediation work done in homes or businesses will be covered by this funding. If any responsible parties are found, they will be asked to reimburse the State.
- 2015 – Present: MDEQ conducts groundwater, soil, and air quality testing upon written access permissions from Franklin Village Plaza owners.
- Friday, March 2, 2018: OCHD encouraged businesses in the Franklin Village Plaza to temporarily and voluntarily close because of potential health risks due to a vapor intrusion discovered by MDEQ.
- Monday March 5, 2018: Franklin Village Plaza businesses received a mandatory evacuation notice from OCHD following MDEQ's discovery of an underground storage tank with unknown chemicals in the crawl space of the building. MDEQ was not able to identify the chemical or potential for harm.
- Tuesday, March 6: Indoor air samples were taken at neighboring businesses and three nearby residences.
- Wednesday March 7: Chemicals from the underground storage tank sampled and sent to laboratory.
For questions regarding the MDEQ Vapor Intrusion program, contact Shane Morrison at 517-284-5063.