How to take a soil sample.

Follow the EPA composite-sampling method. The whole process takes about ten minutes per sample, and you can submit as many samples as you want. We test them on our XRF gun and email the readings back.

What you need.

• A clean spoon or trowel
• A zip-top plastic bag (sandwich-size or larger)
• A permanent marker
• A ruler or anything you can use to measure 4 inches
• A padded envelope or small box for shipping

The four steps.

EPA composite-sampling method, scaled for one residential sample.

1. Mark a 4×4 inch area.

   Pick the spot you want to test — bare dirt within 15 ft of the house is the highest-priority area for pre-1978 homes. Use the ruler to outline a 4×4 inch square on the ground. The area itself is the sample boundary; you do not need to dig out the whole square.

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2. Skim the top half-inch of soil with a spoon.

   Lead from atmospheric deposition (paint dust, leaded gasoline) sits in the top crust. Take only the top half-inch — do not dig deep. Move across the 4×4 area in a few small scoops so the sample represents the whole square, not just one spot.

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3. Bag and label.

   Drop the soil into a zip-top bag. With permanent marker, label the outside of the bag with a short identifier — for example, “North side, drip line, 5/12”. If you are sending multiple samples, give each one a unique label so we can match the readings back to the location.

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4. Mail it to us.

   Put the bagged samples in a padded envelope or small box with a slip of paper containing your name and email so we can send the results back. As many samples as you want, in one shipment. Mailing details below.

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Mail samples to

Include your name and email so we can send the XRF readings back to you. There is no per-sample limit — pack as many bagged samples as you like in a single shipment.

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