Answer: At the federal level, environmental statutes establish standards that may be enforced by federal administrative agencies or by state agencies implementing federally approved state programs. State standards are sometimes more stringent than required by federal law, but they are never more lenient.
Explanation: For example, states may choose to establish and enforce their own programs consistent with the Clean Air Act (CAA) and the Clean Water Act (CWA). If they do not, those standards will be enforced by the U.S. Environmental Protection Agency (EPA), which also enforces the Resource Conservation and Recovery Act (RCRA), and the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA or Superfund). All of these laws are explained in greater detail on the EPA website, which also contains links to corresponding state laws. The National Historic Preservation Act (NHPA) establishes incentives to protect historic and cultural resources, while state and local historic preservation laws may actually restrict physical changes to property.
