The Mission and Installation Contracting Command, Fort Riley, KS intends to solicit and award a firm-fixed price (FFP) contract to acquire aggregate materials, delivered to Fort Riley, KS. Crusted Stone: Commonly referred to as AB3; according to Section 1104 of the Kansas Department of Transportation specification code. Crusted Stone: Commonly referred to as SA-7; according to Section 1111 of the Kansas Department of Transportation specification code. Crusted Stone: Commonly referred to as SS-5; according to Section 1112 of the Kansas Department of Transportation specification code. Natural from the breakup of siliceous / calcareous rock or produced from naturally occurring sand and gravel.