The government intends a sole-source contract modification to Tutor Perini Corporation-Nan Inc. A Joint Venture for critical emergency waterfront stabilization repairs at the Glass Breakwater in Apra Harbor, Guam, following damage from Typhoon Bavi. The $21,000,000 modification covers procurement and placement of an additional 27,000 tons of armor stone to prevent further deterioration of this critical infrastructure. The action is justified under 10 U.S.C. § 3406(c) and FAR 16.507-6(b)(1) because the need is unusually urgent and compelling, and a fair opportunity would cause unacceptable delays.