My tiny zone 7b corner lot is a block from the Delaware Bay in New Jersey. I want to plant to the roadsides, but do not want to risk food crops/trees so close to the pollutants, including a neighbor whose swimming pool drainage runs by once a year. I would appreciate suggestions for good filtering plants for those locations as well as any thoughts on what kind of distance from the road will be safe for edibles. For a start, I have planted bearberries along the windward side, and I think they are going to make it. Looking for ideas for the east-facing, somewhat more sheltered side.
I remember a longtime ago, hearing of how waste water from olive oil production, which is highly toxic and very damaging to the environment, was being cleaned using a water loving grass of some type. Not sure what the particular grass was and I can't find anything through google about it. Obviously there are plants that will tolerate pollutants and some that may help clear them from the soil. whether they just trap them or actually convert them?
Unleaded fuel is as much a problem as leaded fuel from a pollution point of view and diesel is terrible.
If you are worried about ground pollution, then build raised beds from new compost. Air pollution will be hard to avoid so close to a road.