Final answer:
It is illegal to discharge trash, oil, or plastic into federally controlled or state waters according to the Clean Water Act of 1972.
Step-by-step explanation:
It is illegal to discharge trash, oil, or plastic into federally controlled or state waters. These materials are hazardous to water quality and aquatic ecosystems. Since the enactment of the Clean Water Act in 1972, discharging pollutants into U.S. water bodies without a permit has been against the law. This act was a response to environmental crises like the Cuyahoga River fire and aimed to protect and restore water quality, ensuring that waters are swimmable and fishable. Despite the implementation of these regulations, more work is necessary to achieve desirable water quality standards, as not all wastewater undergoes proper treatment before being discharged into natural water bodies, thereby risking further pollution.