The plaintiff was a buyer under a sales contract executed with the defendant with respect to property on which leaking underground storage tanks were discovered after execution of the sales contract. Plaintiff sought specific performance of the contract to require defendant to close the sale and convey the property to it. The Court of Appeals of Michigan held that the unknown was a natural mistake of fact allowing rescission of the contract in this case. The court based this result on the plaintiff's concern for the continuing environmental clean-up responsibilities which plaintiff would bear after closing and plaintiff's need to control the property to prevent the costs of that clean-up from increasing.
Garb-Ko v. Lansing-Lewis Services, Inc., 167 Mich. App. 779, 423 N.W.2d 355 (Mich. Ct. App. 1988).