A contract may be amended where unforeseen circumstances arise after award and during performance. “To qualify for adjustment under a change provision, a contractor must prove, first, that ‘any increased costs arose from conditions differing materially from those indicated in the bid documents;’ and, second, that the changes ‘were reasonably unforeseeable in the light of all the information available to the contractor.’ Willamette Crushing Co. v. State By and Through Dept. of Transp. 188 Ariz. 79, 81, 932 P.2d 1350, 1352 (Ariz.App. Div. 1,1997) (quoting Sterling Millwrights, Inc. v. United States, 26 Cl.Ct. 49, 72 (1992)).
For construction contracts with the State of Arizona or its agencies, the contract must include a provision addressing compensation for delays. A.R.S. § 41-2617.