Water Pollution: Clean Water Act's Regulated Pollutants

The Clean Water Act (CWA) is the primary federal law in the United States that regulates water pollution. It was enacted in 1972 to establish the basic structure for regulating discharges of pollutants into US waters and set quality standards for surface waters. The CWA introduced the National Pollutant Discharge Elimination System (NPDES), a permit system for regulating point sources of pollution, such as industrial facilities, municipal governments, and agricultural operations. Under the CWA, the Environmental Protection Agency (EPA) has implemented pollution control programs, set wastewater standards, and developed national water quality criteria recommendations. The act also addresses nonpoint source pollution, oil discharges, and the protection of wetlands. The EPA regulates toxic and priority pollutants, with the Priority Pollutant List providing a practical framework for testing and regulating specific chemical pollutants.

Characteristics and Values of Pollutants Regulated by the Clean Water Act (CWA)

Oil pollution

The Clean Water Act (CWA) is the primary US law governing pollution control and water quality in the nation's waterways. The CWA establishes the basic structure for regulating the discharge of pollutants into US waters and sets quality standards for surface waters.

Under the CWA, the Environmental Protection Agency (EPA) has implemented pollution control programs, including setting wastewater standards for industry and water quality standards for all contaminants in surface waters. The CWA makes it unlawful to discharge any pollutant from a point source into navigable waters without a permit from the EPA's National Pollutant Discharge Elimination System (NPDES).

The 1990 Oil Pollution Act (OPA 90) amended the CWA, introducing new requirements for contingency planning by government and industry under the National Oil and Hazardous Substances Pollution Contingency Plan. OPA 90 increased penalties for regulatory non-compliance, enhanced the federal government's response and enforcement authorities, and preserved state authority to establish laws governing oil spills.

The EPA regulates all waste streams generated from offshore oil and gas activities, primarily through general permits. The EPA's guidelines for these permits aim to prevent the degradation of the marine environment and require an assessment of the effects of proposed discharges on sensitive biology. The EPA also publishes effluent limitations guidelines (ELG) for existing point source dischargers, such as exploratory wells and grandfathered development and production facilities. These guidelines identify three broad categories of pollutants: conventional, toxic, and non-conventional. Oil and grease, including hydrocarbons, fats, oils, waxes, and high-molecular fatty acids, are listed as conventional pollutants.

Toxic pollutants

The Clean Water Act (CWA) is the primary US law governing pollution control and water quality in the country's waterways. The CWA establishes the basic structure for regulating the discharge of pollutants into US waters and sets quality standards for surface waters.

The CWA was enacted in 1948 as the Federal Water Pollution Control Act, but it was significantly reorganised and expanded in 1972, when it also got its current name. The law was further amended in 1977 to include the Toxic Pollutant List, which was developed in 1976. This list was intended to be used as a starting point for the Environmental Protection Agency (EPA) and individual states to address the problems of toxics in waterways. It contains 65 entries, but these are broad categories of pollutants rather than individual pollutants. For example, "chlorinated benzenes" is a group that contains hundreds of compounds, and there is no test for the group as a whole.

To make the Toxic Pollutant List more practical for water testing and regulatory purposes, the EPA developed the Priority Pollutant List in 1977. This list includes specific chemical names, making it more usable for the purposes assigned to the EPA by the CWA.

The CWA makes it unlawful for any person to discharge any pollutant from a point source into US waters unless a National Pollutant Discharge Elimination System (NPDES) permit is obtained. The EPA issues technology-based effluent guidelines that establish discharge standards based on available and economically achievable treatment technologies. The EPA also regulates all waste streams generated from offshore oil and gas activities and funds the construction of sewage treatment plants.

The Oil Pollution Act of 1990 (OPA 90) further amended the CWA, strengthening the federal government's response and enforcement authorities and increasing penalties for regulatory non-compliance.

Priority pollutants

The Clean Water Act (CWA) establishes the basic structure for regulating the discharge of pollutants into US waters and standardising water quality for surface waters. The CWA prohibits the discharge of any pollutant from a point source into navigable waters without a permit. The Environmental Protection Agency (EPA) implements pollution control programs and sets wastewater standards for industries.

The Toxic Pollutant List was developed in 1976 and added to the CWA by Congress in 1977. This list was intended to be used as a starting point for the EPA and states to ensure that Effluent Guidelines regulations, water quality criteria, and NPDES permit requirements addressed the problems of toxics in waterways. However, the list consisted of broad categories of pollutants rather than specific, individual pollutants.

To address this, the EPA developed the Priority Pollutant List in 1977 to make the implementation of the Toxic Pollutant List more practical for water testing and regulatory purposes. The Priority Pollutant List includes specific chemical names, making it more usable for testing and regulation. It was included in the Steam Electric Power Generating Category to support regulations for that category. The Priority Pollutant List is not limited to this industrial category and is relevant to other areas as well.

The EPA used four criteria to select and prioritize specific pollutants for the Priority Pollutant List:

• All pollutants specifically named on the list of toxic pollutants were included.
• A chemical standard had to be available to perform testing for the pollutant.
• The pollutant had to have been reported as found in water with a frequency of occurrence of at least 2.5%.
• The pollutant had to have been produced in significant quantities, as reported in the Stanford Research Institute's "1976 Directory of Chemical Producers, USA."

It is important to note that the Priority Pollutant List is subject to change over time. For example, in 1981, three pollutants were removed from the list, and while new entries have been added, some portions of the list may become outdated. The pollutants on these lists are not the only ones regulated under the CWA programs, and the EPA continues to develop and implement pollution control programs to address water quality issues.

Point source pollution

The Clean Water Act (CWA) was enacted in 1948 as the Federal Water Pollution Control Act and was significantly amended in 1972. The CWA is the primary law governing pollution control and water quality in the United States. It aims to restore and maintain the chemical, physical, and biological integrity of the nation's waters. The Environmental Protection Agency (EPA) is responsible for implementing and enforcing the CWA.

The CWA regulates point source pollution, which refers to any discernible, confined, and discrete conveyance from which pollutants are discharged into navigable waters. This includes pipes, ditches, tunnels, conduits, wells, containers, vessels, and other similar sources. Point source pollution is strictly regulated by the CWA, and dischargers are required to obtain permits and comply with technology-based effluent limitations guidelines (ELG).

Existing point source dischargers, such as exploratory wells and certain production facilities, are subject to ELG regulations. Regulated wastes include drilling fluids, produced water, sanitary wastes, and deck drainage. The CWA identifies three broad categories of pollutants: conventional, toxic, and non-conventional. Conventional pollutants are commonly found in sanitary wastes and include fecal coliform, suspended solids, biochemical oxygen demand, pH alterations, and oil and grease. Toxic pollutants are specifically targeted by the CWA, with the EPA developing a Priority Pollutant List to facilitate practical testing and regulation. Non-conventional pollutants are those that do not fall neatly into the other two categories and may require more specialized treatment methods.

To ensure compliance, the EPA issues permits through its National Pollutant Discharge Elimination System (NPDES) permit program. These permits set specific discharge standards based on available treatment technologies and economic feasibility. The EPA also regulates waste streams from offshore oil and gas activities and has the authority to prevent discharges into ocean waters that do not comply with established guidelines. Additionally, the CWA includes the Oil Pollution Prevention regulation, which mandates that specific facilities develop Spill Prevention, Control, and Countermeasure (SPCC) Plans to prevent oil from reaching navigable waters and causing significant environmental damage.

In summary, the Clean Water Act plays a crucial role in regulating point source pollution by establishing permit requirements, setting wastewater standards, and providing guidelines for the management and treatment of various types of pollutants. The EPA, as the enforcing agency, utilizes tools such as the NPDES permit program and the Priority Pollutant List to effectively control and reduce point source pollution, ultimately contributing to the restoration and maintenance of the nation's water quality.

Nonpoint source pollution

The Clean Water Act (CWA) was established in 1972 to regulate the discharge of pollutants into the waters of the United States and set quality standards for surface waters. The Act made it unlawful to discharge pollutants from a point source into navigable waters without a permit.

Nonpoint source (NPS) pollution refers to any source of water pollution that does not meet the legal definition of "point source" as defined by the CWA. Point sources include discernible, confined, and discrete conveyances such as pipes, ditches, tunnels, and wells, from which pollutants are discharged. Nonpoint sources, on the other hand, are more diffuse and challenging to regulate. NPS pollution includes stormwater runoff, agricultural activities, urban drainage, and natural sources such as wildfires and animal waste.

The CWA has been successful in reducing water pollution from point sources, but it has been less effective in addressing nonpoint source pollution. This is because nonpoint source pollution is more challenging to regulate and often comes from a variety of sources, including agricultural practices, urban runoff, and forestry activities. NPS pollution can include fertilizers, herbicides, pesticides, oil, and toxic chemicals from stormwater runoff, as well as sediment from construction sites, salt from irrigation and snow removal, and drainage from abandoned mines.

To address NPS pollution, the EPA has developed programs and guidelines, such as the Nonpoint Source Management Program, to provide background information and recommendations for reducing NPS pollution. The EPA has also published fact sheets that offer specific guidance for different sectors, including agriculture, forestry, boating, and households, on reducing their impact on nonpoint source pollution.

Despite these efforts, the current approach to NPS pollution is insufficient to restore and maintain the nation's water quality. To achieve the goals of the CWA, Congress, the EPA, and state and local authorities must work together to provide grant funding, financing, and more stringent regulatory standards to address the complex nature of NPS pollution.

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