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Sampling Instructions

1. Gather Supplies

Use a bulb planter (preferred), trowel, shovel, large spoon or knife to take samples, plastic ziplock bags and a permanent marker.

Sampling supplies

2. Create Sampling Areas

Gathering multiple samples over large sites will give more accurate results. If the site has different areas (such as a front and back yard or multiple beds), splitting the site into different sampling areas can give more accurate results and help isolate "hot spots" with higher contamination. See recommendations for creating sampling areas in food production and other types of sites. 

Food production sites

If there is just one bed or growing area, only 1 composite sample is needed. If there are multiple beds, make 1 composite sample from groups of similar beds. Beds can be grouped by the soil mix, their location, their age, or other factors. It is recommended to create a separate sampling area for beds within 10 feet of a current or former pre-1960s structure or road. 

Non-food production sites (yards, play areas, etc)

Gather 1 composite sample per yard. Gather 1 additional composite for each play area and the dripline of previous or current structures built before 1960. Click here to view a diagram of a dripline. 

3. Gather Samples

The sides of the sample or the sampling hole should be straight up and down and not slanted. This ensures that the soil is representative and not oversampling the top. Samples are 4-6 inches deep for food production sites and 1 inch deep for non-food production sites. Gather 1 composite sample per sampling area (see above). Gather 5 subsamples into a bucket and mix together to create a composite sample. Place 1-2 cups of the mixed soil into a bag and label with a site ID that you will use to match the test result to the sampling area (such as "front yard" and "back yard" or "garden bed 1" and "garden bed 2".

4. Submit Samples

Open sample bags for 2 days or until the soil appears dry. Seal the bag and place in another bag. Include your name, email and phone number, and the site address with the samples (either on a piece of paper with the samples or on the sample bags). Visit to review test package options and visit to order testing.