That email from the city kind of freaked the heck out of me. I never thought to have my soil tested for contaminants. The soil test kits sold through seed catalogs and garden stores only work for pH and macronutrients, not contaminants. To really find out what’s in your soil, you need to send it to a lab. I think since my kid eats what I grow, I’m probably going to do it.
The Washington State University Ag extension program has a number of links to soil testing resources here. They are largely for the Pacific Northwest, but for other regions you could just look online for “soil testing” and your area, or contact the closest ag program.
Here‘s a link to the WSU list of soil testing labs for the Pacific Northwest. It’s pretty hefty, a 13 page PDF.
I obviously need to do more research here! I will try to post results soon.