where did the concept of this project originate from?
It was first hypothesized by the Hungarian scientist Leo Szilard. He realized that if a nuclear reaction produced neutrons or dineutrons, which then caused further nuclear reactions, the process might be self-perpetuating.
Chicago Pile-1
The concept of a nuclear chain reaction was first hypothesized by the Hungarian scientist Leo Szilard on 12 September 1933. Szilard realized that if a nuclear reaction produced neutrons or dineutrons, which then caused further nuclear reactions, the process might be self-perpetuating. 
when did we first start using nuclear energy 1970's what is this power? It is a power that uses nuclear reactions that release nuclear energy to generate heat, which most frequently is then used in steam turbines to produce electricity in a nuclear power plant. what happens to the waste of this process? It is disposed. is it used in space ? Yes. has it faced any attacks? UNANSWERABLE where was this technology first used? United States of America any particular project in that country where this was used? Yes. The first man-made reactor, the research reactor known as Chicago Pile-1 what was its importance? The successful test of CP-1 not only proved that a nuclear reactor was feasible, it demonstrated that the "k" factor was larger than originally thought. what site was chosen for this? A suitable location long, wide and high, sunk slightly below ground level, in a space under the stands at Stagg Field
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Chicago Pile-1 [SEP] Origins
The idea of chemical chain reactions was first suggested in 1913 by the German chemist Max Bodenstein for a situation in which two molecules react to form not just the final reaction products, but also some unstable molecules which can further react with the original substances to cause more to react. The concept of a nuclear chain reaction was first hypothesized by the Hungarian scientist Leo Szilard on 12 September 1933. Szilard realized that if a nuclear reaction produced neutrons or dineutrons, which then caused further nuclear reactions, the process might be self-perpetuating. Szilard proposed using mixtures of lighter known isotopes which produced neutrons in copious amounts, and also entertained the possibility of using uranium as a fuel.