what was  its significance ?
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. It removed the objections to the use of air or water as a coolant rather than expensive helium. It also meant that there was greater latitude in the choice of materials for coolant pipes and control mechanisms.
Chicago Pile-1
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. This removed the objections to the use of air or water as a coolant rather than expensive helium. It also meant that there was greater latitude in the choice of materials for coolant pipes and control mechanisms. 
where can the resource for nuclear energy be found It is produced by nuclear fission of uranium and plutonium. what is nuclear power ? It is the use of 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. which was the first nuclear reactor ? Chicago Pile-1 does this power produce any waste ? Yes, spent nuclear fuel is the waste generated. what are different types of waste ? Low-level radioactive waste, is one type of nuclear waste. It is found in the form of contaminated items like clothing, hand tools, water purifier resins, and the materials of which the reactor itself is built. what is nuclear fusion ? It is a proposed form of power generation that would generate electricity by using heat from nuclear fusion reactions. how is the waste disposed off ? There are no commercial scale purpose built underground high-level waste repositories in operation. Presently, waste is mainly stored at individual reactor sites and there are over 430 locations around the world where radioactive material continues to accumulate. the first nuclear reactor you mentioned above where is located ? Stagg Field
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Chicago Pile-1 [SEP] Significance and commemoration
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. This removed the objections to the use of air or water as a coolant rather than expensive helium. It also meant that there was greater latitude in the choice of materials for coolant pipes and control mechanisms. Wigner now pressed ahead with his design for a water-cooled production reactor. There remained concerns about the ability of a graphite-moderated reactor being able to produce plutonium on industrial scale, and for this reason the Manhattan Project continued the development of heavy water production facilities.