Government Contracting Database
Differing Site Conditions Clause
This clause places the risk of unknown site conditions (sometimes referred to as “changed conditions”) on the government. The purpose of the clause is to avoid having contractors place contingencies in their bids for unknown subsurface or other physical site conditions. There are two types of differing site conditions and these are sometimes referred to as “Type I” and “Type II” differing site conditions.
“Type I” conditions are physical conditions which differ materially from those indicated in the contract. For a contractor to receive an equitable adjustment under this type of differing site condition, the contract must contain a representation of the condition in the form of specification language, boring logs, drawings, or a description of soils, etc., and the condition encountered must differ materially from what was represented. A classic example of a “Type I” condition occurs when the boring logs do not show rock and the contractor encounters rock which requires extensive excavation efforts.
A “Type II” differing site condition is defined as “unknown physical conditions of an unusual nature which differ materially from those ordinarily encountered and generally recognized as inhering in work of the character provided for in the contract.” An example of a “Type II” condition is the encountering of a subsurface structure in an area which appeared to only contain soil.
The clause requires the contractor to give prompt notice to the government of the condition and not to disturb it before the government representatives have investigated it. It is best to make this a written notice to the government. The government is required to investigate and to give the contractor direction as to what to do about the condition.
Differing Site Conditions
- The Contractor shall promptly, and before such conditions are disturbed, notify the Contracting Officer in writing of: (1) subsurface or latent physical conditions at the site differing materially from those indicated in this contract, or (2) unknown physical conditions at the site, of an unusual nature, differing materially from those ordinarily encountered and generally recognized as inhering in work of the character provided for in this contract. The Contracting Officer shall promptly investigate the conditions, and if he finds that such conditions do materially so differ and cause an increase or decrease in the Contractor’s cost of, or the time required for, performance of any part of the work under this contract, whether or not changed as a result of such conditions, an equitable adjustment shall be made and the contract modified in writing accordingly.
- No claim of the Contractor under this clause shall be allowed unless the Contractor has given the notice required in (a) above; provided, however, the time prescribed therefore may be extended by the government.
- No claim by the Contractor for an equitable adjustment hereunder shall be allowed if asserted after final payment under this contract.
Updated: June 21, 2018