February 22, 2018
On Thursday, February 22, 2018, the President signed into law:
S. 1438, the "Gateway Arch National Park Designation Act," which redesignates the Jefferson National Expansion Memorial in the State of Missouri as the "Gateway Arch National Park."
Donald J. Trump, President Donald J. Trump Signs S. 1438 into Law Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/332113