I didn't even do the inexpensive test for my yard, as I live near a busy street and the heavy metal content was certain.  I decided on a modest 4 x 8 raised bed and proceeded to dig out about 18 inches of soil, put in wooden sides for the bed and hauled in "good" dirt (though not certified organic). I had to do some sudden landscaping that would accommodate the displaced dirt and even this small bed required a LOT of new dirt. I hadn't thought about the pesticide/herbicide issue until my neighbor, slightly up the hill from me, started attacking his weeds with a vengeance, using spray, and it just rolled down into my yard. The raised bed plants didn't die, but the rhubarb and raspberries I'd planted outside the beds did. The article about charcoal is very interesting and I'm also curious about how other locations are regulating the use of chemicals on lawns. Education is so important - there's an organic farm in Weston MA that has a program/service that helps people rethink suburban lawn care.