What are the three most important reasons humans have not done a very good job in looking after the environment.

Well one of them I just learned about this, is that there is radioactive waste caused by the Hanford program. Since apparently there was one that started leaking that contains the most toxic radioactive waste in the container. So one is the creation of atomic or nuclear bombs waste and how it could pollute the rivers, at Hanford, if it escapes the container then the waste will travel through the underground water to the Columbia River. Two, Urban air pollution, this is combustion of fossil fuels, vehicle engines, industrial production, and burning off biomass. Three, surface water pollution, this happens when waste substances get disposed of or transported to bodies of water.