<Li> Pipeline and Hazardous Materials Safety Administration (PHMSA) </Li> <Li> Saint Lawrence Seaway Development Corporation (SLSDC) </Li> <Li> John A. Volpe National Transportation Systems Center </Li> <Ul> <Li> Transportation Security Administration--transferred to Department of Homeland Security in 2003 </Li> <Li> United States Coast Guard--transferred to Department of Homeland Security in 2003 </Li> <Li> Surface Transportation Board (STB)--spun off as an independent federal agency in 2015 </Li> </Ul>

What does the us secretary of transportation do