Civil Engineer Marc Dolder (Foreground/Red Shirt), who supports the Chickamauga Lock Replacement Project with the Integrated Project Office on the Tennessee River in Chattanooga, Tennessee, and Civil Engineer Caleb Ayres (Background/Black Shirt), who supports the Kentucky Lock Addition Project on the Tennessee River in Grand Rivers, Kentucky, allow students to simulate testing concrete during a Tennessee STEAM Festival event Sept. 5, 2024, at Antioch Middle School in Antioch, Tennessee. They also explained the requirements for certification. (USACE Photo by Lee Roberts)