>>1395829>>1395840There should be some sort of agency in your area for farmers to send their soil to for various testing. Those people should also know where to send soil for pollutant testing if you wish to do that too, if they don't already do it. The cheapest option is to get a few liquid soil tests from amazon. Luster Leaf Rapitest is the brand I use. There's 4 tests and you can do that ten times for each test with the pictured kit.
If you live in the USA,
http://pickyourown.org/countyextensionagentoffices.htm 