I don't know what the highest best use is for your property but it doesn't sound like enough money to make it worth binding yourself into a contract.
1 hour of a lawyers time would likely be more than the bonus. If you are eventually stuck with the clean-up, it could be far more costly than what you receive. If there is hazardous clean-up, even more so. I look at it this way, O&G companies are horrible at performing according to contracts so each contract is = to either eventual great unhappiness or a lawsuit, in which case you won't be very happy either.
I really think it is important to run this past a lawyer and not restrict him to a quick read.
In my personal situation, I would pass on it because the absolute highest gain possible isn't worth burdening myself and my property with the contract. I would look more favorably on the sale of my surface interest (which would relieve you of liability issues), unless there were some sentimental value? If there were some sentimental value? I would certainly not want them using my surface because I presume, with good reason, that they will not leave it in the condition that they found it. Some points to ponder.