Gardens Resources and FAQ
Community Gardener Resources
Healthy Garden Habits Infographic
Contaminant Fact Sheets
Soil Testing Resources
Urban Gardening in and around Brownfields
NC State University – Minimizing Risks of Soil Contaminants in Urban Gardens
Frequently Asked Questions
- How do I find the past or historical land uses at my garden site?
- What about my water source? Is it contaminant-free?
- What does bioavailability mean?
- How do I interpret my soil contaminant test results?
- What about PFAS in my garden?
- Where can I find resources on how to use less harmful chemicals in garden materials, for example, wood sealants?
- Why are children more at risk from soil contamination exposure?
1. How do I find the past or historical land uses at my garden site?
There are several mapping tools available online that may help you to research prior land uses at your site:
North Carolina Department of Environmental Quality (DEQ) Division of Waste Management (DWM) Site Locator Tool. The Site Locator Tool is a recent compilation of federal, state, and local site data that is collected on polluted sites, waste treatment and storage facilities, and other hazardous site locations.
Sanborn Fire Maps: These maps were created by the Sanborn Map Company to visualize all existing structures on parcels of land across the entire country for fire insurance purposes, in some cases going back as far as the 1800s. They are currently held at the Library of Congress, but UNC has a curated collection of North Carolina maps by county that is open access and has a few more maps than the Library of Congress: https://web.lib.unc.edu/nc-maps/sanborn.php North Carolina State University libraries also has a collection of Sanborn Maps that has slightly more restricted access to researchers within North Carolina, or NCSU affiliates: https://www.lib.ncsu.edu/maps/sanborn.html
Deeds from county or local governments: Sometimes it may be necessary to seek out historical property deeds may be necessary to find out about the previous owners of a site or previous site activity. Any party who has ever dumped waste at a site is technically a “Potentially Responsible Party” who should be involved in cleanup of the site. Checking the county for records including the site’s property values may be a helpful step at this part of the process.
2. What about my water source? Is it contaminant-free?
If you are concerned about contaminants that may be in your garden’s watering/irrigation sources, you can participate in the NC DPH’s well water testing program through your county’s environmental health department. Visit this page for more information: https://epi.dph.ncdhhs.gov/oee/wellwater/howtotest.html
3. What does bioavailability mean?
Bioavailability means how much of a contaminant gets absorbed into the body after exposure (in this case, through eating, or ingestion). To learn more about bioavailability of arsenic and lead in soils at Superfund sites, check out this fact sheet produced by the University of Arizona and UNC-Chapel Hill Superfund Research Program Centers.
4. How do I interpret my soil contaminant test results?
For an example of how to interpret common soil testing results for contaminants, check out this Story Map created by the Duke University Superfund Research Center RTC and CEC for Garner Grows garden. We can help you to interpret your specific contaminant test results based on current regulatory guidance for residential soils in North Carolina, if they exist for the contaminant you tested for. Contact SuperfundCEC@duke.edu for more information.
5. What about PFAS in my garden?
Recent studies suggest that PFAS (perfluoroalkyl substances) may travel via water and contaminate garden produce. The best remedy is to add clean organic matter to your garden to reduce PFAS in soils to prevent plant accumulation in soils. Find more information here.
6. Where can I find resources on how to use less harmful chemicals in garden materials, for example, wood sealants?
Almost every product has something called a Material Safety Data Sheet (SDS) to go along with it that includes potential exposure hazards and exposure reduction tips, To find more information on the potential exposure hazards and health effects of many household products including sealants, anyone can search for the exact product name in the US DHHS Household Products Database, to see additional information for about the ingredients, health effects, and precautions. This US DHHS database links to another “Consumer Product Information database,” maintained by a non-governmental agency, that contains many of the currently available Safety Data Sheets, which can be searched by brand name.
7. Why are children more at risk from soil contamination exposure?
Small doses matter. Children breathe, eat, and drink more relative to their size than adults. Their bodies and brains are still developing. They spend more time on the ground and often put things (like dirt) into their mouths. They also have more skin surface area than adults.