Yes all of this is possible. But incredibly costly and pointless on a large (farm) scale. I was (as another poster pointed out) being hyberbolic. But realistically there's no way we'd do what you're saying for hundreds of acres.
You can actually grow edible things, though. Carefully. My understanding is that the metals accumulate in the tissues of the plant but not in its fruits. Depending on the kind of fruit. So actually orchard crops can ironically be safer in these old orchards, as the metals should not accumulate into the fruits. Instead they accumulate in the vascular tissues of the plant (stems, leaves, etc.)
So:
* Avoid bare soil, as the metals would be more exposed this way.
* Don't eat or be exposed much to the plant tissues growin there (which includes things like making hay or straw)
* Could maybe grow fruits, but carefully.
* Even mowing could be dangerous, maybe.
There's people who talk about cleanup using fungus, to accumulate then dispose. But I truly wonder about if this would ever be effective.
What about testing your soil, and if there are high levels of lead then either put in raised beds or don't grow edible things?