In the US, there are many laws governing the amount of pollution generated on private land. It's not easy to get a handle on these laws.
One problem, which you mention, is our federalism. In the US, you are likely to be subject to federal, state and local governments. And each of those governments is likely to have different rules covering different aspects of keeping air, water and ground clean. Those different rules may be enforced by different agencies, or different parts of the same agencies. Finally, regulatory agencies each have their own processes for making and enforcing law.
Put these various governments, statutes, rules and procedures together and the result can be overwhelming and baffling, even to experts.
Unfortunately, if you want to understand what laws you will need to pay attention to you, you have to make sense of this system. If you don't, you are going to continue to be puzzled, wondering which of the various laws or agencies you hear about affect you.
My recommendation for getting a handle on this mess is to start with these overview articles. These lay out the basics of pollution control in the US. They are easy reads, and give a sense of the various pieces -- Congress, President, Courts, Agencies, statutes, rules and so on -- what they do, and of how they all fit together. If you know the big picture, it's easier to keep track of the various detailed parts you come across as you dive into the rules regarding specific topics.
As far as the law of hazardous waste, the EPA (Environmental Protection Agency) has some nice web pages covering various aspects of the law of hazardous wastes. You should probably start with their learn-the-basics page. At the federal level, hazard waste is covered by the RCRA (Resource Conservation and Recovery Act). EPA has a page giving an overview of the RCRA generally, and a page giving an overview of its application to hazardous waste.
Once you've digested these, you'll be in good shape to use your favorite search engine to do more focused searches. You'll also be in good shape to recognize which of the results you get will be useful to answer your specific questions.