Short answers, pulled from the story.
Leslie Groves assumed command of the Manhattan Project on the 23rd of September 1942. He attended a meeting that same day which established a Military Policy Committee consisting of Vannevar Bush, Thomas Somervell, and Rear Admiral William R. Purnell.
The site initially known as the Kingston Demolition Range was officially renamed the Clinton Engineer Works in early 1943. The population of Oak Ridge peaked at 75,000 in May 1945 with 82,000 people employed at the facility.
Lieutenant Colonel Kenneth Nichols requested the transfer of 6,000 tons of silver bullion from the West Point Bullion Depository on the 3rd of August 1942 to substitute for copper in electromagnetic separation devices. Ultimately tons were used to construct the Y-12 plant at Oak Ridge.
The first nuclear device ever detonated was an implosion-type bomb during the Trinity test conducted at White Sands Proving Ground in New Mexico on the 16th of July 1945. This event marked the culmination of development efforts directed toward a gun-type fission weapon and alternative methods like implosion.
The Manhattan Project maintained control over American atomic weapons research and production until the formation of the United States Atomic Energy Commission in January 1947. Between 1944 and his resignation from the Trust in 1947 Leslie Groves deposited a total of $37.5 million into the Combined Development Trust.