Federal Water Pollution Control Act. aka: The Clean Water Act (1972): Eliminates discharge into navigable waters, and ensures water quality to protect fish and wildlife. Especially, the laws goal is to achieve water that is drinkable, swimmable and fishable (33 U.S.C. §1251).
Marine Protection, Research & Sanctuaries Act. aka The Ocean Dumping Act (1972): Prohibits dumping into the ocean that could endanger human health, welfare, the marine environment, ecological systems or economic potentialities. Specific types of dumping are allowed, (most notably dredge sludge) and are permitted by the EPA (16 U.S.C. §1431; 33 U.S.C. §1401).
Marine Plastic Pollution Research & Control Act (1987): The implementation of MARPOL 73/78, which focuses on marine debris from ships. It prohibits the dumping of all plastic into the ocean. The law requires EPA and NOAA to study and monitor floating debris and that all US ports have proper reception facilities (33 U.S.C. §§1905-1915).
Microbead-Free Waters Act (2015): Prohibits the sale and distribution of cosmetics that contain rinse off microbeads (21 U.S.C. §331).
Read more from the EPA here