The Boards and Courts have a long established precedent of compensating contractors for differing site conditions that are experienced during attempted performance. Pursuant to FAR 52.236-2, Differing Site Conditions, incorporated into most construction contracts, the contractor has a right to be compensated for unknown physical conditions at the site, of an unusual nature, which differ materially from those indicated in the contract.

        In order to recover for unknown physical conditions at the site (Type II Differing Site Conditions), a contractor must show that it did not know about the physical condition, that it could not have anticipated the condition from inspection or general experience, and that the condition varied from the norm in similar contracting work. A site investigation clause does not nullify the provisions of the differing site conditions clause, nor does it require the contractor to discover, at his peril, conditions at the site that would not be reasonably ascertainable by a reasonable pre-bid site investigation, the contractor is chargeable with the knowledge reasonably ascertainable on proper site investigation by a prudent bidder, in the absence of any misrepresentation or withholding of information by the Government.

Lathan Co. v. United States, 20 Cl. Ct. 122 (1990);

George E. Jensen Contractor, Inc., VACAB-1322, 78-2 BCA ¶ 13,359 (1978);

CM of North Dakota, Inc., VABCA No. 3986.