Two years later, in an attempt to destroy the unused Jumbo before it and its 12 million dollar cost came to the attention of a congressional investigating committee, Manhattan Project Director General Groves ordered two junior officers from the Special Weapons Division at Sandia Army Base in Albuquerque to test Jumbo. The Army officers placed eight 500-pound conventional bombs in the bottom of Jumbo. Since the bombs were on the bottom of Jumbo, and not the center (the correct position), the resultant explosion blew both ends off Jumbo. Unable to totally destroy Jumbo, the Army then buried it in the desert near Trinity Site. It was not until the early 1970s that the impressive remains of Jumbo, still weighing over 180 tons, were moved to their present location. SCHMIDT-McDONALD RANCH HOUSE The Schmidt-McDonald ranch house is located two miles south of Ground Zero. The property encompasses about three acres and consists of the main house and assorted outbuildings. The house, surrounded by a low stone wall, was built in 1913 by Franz Schmidt, a German immigrant and homesteader. In the 1920s Schmidt sold the ranch to George McDonald and moved to Florida. The ranch house is a one-story, 1,750 square-foot adobe (mud bricks) building. An ice house is located on the west side along with an 9'-4" deep underground cistern. A 14 by 18.5 foot stone addition, which included a modern bathroom, was added onto the north side in the 1930s. East of the house there is a large, divided concrete water storage tank and a windmill. South of the windmill are the remains of a bunkhouse, and a barn which also served as a garage. Further to the east are corrals and holding pens for livestock. The McDonalds vacated their ranch house and their thousands of acres of marginal range land in early 1942 when it became part of the Alamogordo Bombing and Gunnery Range. The old house remained empty until Manhattan Project personnel arrived in 1945. Then a spacious room in the northeast corner of the house was selected by the Project personnel for the assembly of the plutonium core of the Trinity device. Workmen installed work benches, tables, and other equipment in this large room. To keep the desert dust and sand out, the room's windows and cracks were covered with plastic and sealed with tape. The core of the bomb consisted of two hemispheres of plutonium, (Pu-239), and an initiator. According to reports, while scientists assembled the initiator and the Pu-239 hemispheres, jeeps were positioned outside with their engines running for a quick getaway if needed. Detection devices were used to monitor radiation levels in the room, and when fully assembled the core was warm to the touch. The completed core was later transported the two miles to Ground Zero, inserted into the bomb assembly, and raised to the top of the tower.