oil in ground

First of all before you get too carried away let's define quantity and area covered here.

If you're like us, you have a couple of tractors a truck or 2 and a family car. All together about 5 galons of oil. And you wouldn't likely change the oil much more than twice a year in the tractors and maybe 3 time a year in the car and trucks so all together you have maybe 10 to 15 gallons a year.

Now how much area was this 15 gallons of oil spread over? Did you just do it around the house and barn or did you do the whole lane back to your fields? Was it sprayed on in a fine mist or just poured out of a bucket?

My guess would be that unless they sample the driveway itself they will never find anything.

Think of it this way. If their samples were that precise they would be more likely to find the spot where you blew a hydraulic hose or some other field break down than your dust contol.

Just my opinion though

Firstly, don't tell anyone about the oil spraying if you can avoid it. Let who ever the city hires to do the work make their own decisions as to what problems they will be concerned with and look for.

Aside from that; what's there is there. If something is found it will need to be dealt with in accordance with the oil and hazardous material regulations of your state. Don't be proactive at this point. They may not find anything, and if they do it may not be considered a problem that needs to be cleaned up.

If your soils are "tight" (i.e., clayey with low permeabilty) the oil may have stayed near the soil surface (though is also may have moved overland with rain runoff). Oil is an organic material that certain bacteria will eat for lunch. If nutrients were available along with some warmth and moisture and the oil stayed near the surface there may not be much left after 15 years.

Used oil has metals associated with it (lead, copper, chromium, cadmium) but unless there was some migration to a wetland or pond, or for some reason your used oil had unusually high levels of metals, the levels in soil resulting from that practice are not likely to be a signficant concern.

Good luck.

By your description, I take it you used to spread the oil on the driveway and roads, not simply all over the yard and fields.

The oil on the roads will stay and slowly seep down, but it tends not to migrate sideways. So you're not likely to find it in the lawn areas.

So, the next issue has to do with the location and depth of these test drillings. If they test the driveway and roads, they are going to come up with positive readings. In the field and lawn, they will not.

But, if you guys dumped the heck out of oil, and they drill deep, they still may come up with a positive reading.

There is also the matter of at what level does your jurisdiction require remediation or other actions. You need to check into this as well, so you know what things you're potentially looking at.

You might want to check with a remediation company ahead of time and get their opinion.