Task: Question Generation
Input (English): Passage: This portion of the quiet rural area was called Black Oak Ridge and was the northernmost of five principal oak- and pine-covered ridges around the meandering Clinch River. It was a verdant, beautiful countryside with rolling hills covered with dogwood and full of partridge and deer. To the east were the Great Smoky Mountains, to the west the peaks of the Cumberland Mountains.
The site was located in Roane County and Anderson County, and lay roughly halfway between the two county seats of Kingston and Clinton. Its greatest drawback was that a major road, Tennessee State Route 61, ran through it. Stone & Webster considered the possibility of re-routing the road. The Ohio River Division (ORD) of the Corps of Engineers estimated that it would cost $4.25 million to purchase the entire 83,000-acre (34,000 ha) site.
Groves became the director of the Manhattan Project on 23 September, with the rank of brigadier general. That afternoon, he took a train to Knoxville, where he met with Marshall. After touring the site, Groves concluded that the site "was an even better choice than I had anticipated". He called Colonel John J. O'Brien of the Corps of Engineers' Real Estate Branch, and told him to proceed with acquiring the land. The site was initially known as the Kingston Demolition Range; it officially became the Clinton Engineer Works (CEW) in January 1943, and was given the codename Site X. After the township was established in mid-1943, the name Oak Ridge was chosen from employee suggestions. It met with the Manhattan District's approval because "its rural connotation held outside curiosity to a minimum". Oak Ridge then became the site's postal address, but the site itself was not officially renamed Oak Ridge until 1947.
Output (English): What was the name of the person who called O'Brien and told him to proceed with acquiring the land?