Clean Water Act (CWA)

The primary objective of the Federal Water Pollution Control Act, commonly referred to as the Clean Water Act (CWA), is to restore and maintain the chemical, physical, and biological integrity of the nation's surface waters. Pollutants regulated under the CWA include "priority" pollutants, including various toxic pollutants; "conventional" pollutants, such as biochemical oxygen demand (BOD), total suspended solids (TSS), fecal coliform, oil and grease, and pH; and "non-conventional" pollutants, including any pollutant not identified as either conventional or priority.

NPDES Permits
The CWA regulates both direct and indirect discharges. The National Pollutant Discharge Elimination System (NPDES) program (CWA §402) controls direct discharges into navigable waters. Direct discharges or "point source" discharges are from sources such as pipes and sewers. These include discharges of industrial and municipal wastewater, as well as storm water conveyed through a municipal separate storm water system (MS4). NPDES permits, issued by either EPA or an authorized State (EPA has authorized 44 States to administer the NPDES program), contain industry-specific, technology-based and/or water quality-based limits, and establish pollutant monitoring requirements. Each municipality or industry that intends to discharge into the nation's waters must obtain a permit prior to initiating its discharge. A permit applicant must provide quantitative analytical data identifying the types of pollutants present in the facility's effluent. The permit will then set the conditions and effluent limitations on the facility discharges.

An NPDES permit also includes discharge limits based on Federal or State water quality criteria or standards, that were designed to protect designated uses of surface waters, such as supporting aquatic life or recreation. These standards, unlike the technological standards, generally do not take into account technological feasibility or costs. Water quality criteria and standards vary from State to State, and site to site, depending on the use classification of the receiving body of water. Most States follow EPA guidelines which propose aquatic life and human health criteria for many of the 126 priority pollutants.

Local governments who own and operate wastewater treatment plants are required to apply for and obtain an NPDES permit. These permits contain a variety of required elements, including discharge limits; monitoring, reporting, and recordkeeping requirements; and requirements for managing residuals.

In addition to requiring storm water permits for collection systems, the Clean Water Act may also require that industrial or local government operations obtain or be covered by storm water permits. Such operations may include construction activities (e.g., roads, buildings) or storage of chemicals or hazardous materials.

EPA has developed technology-based standards for industrial users of POTWs. Different standards apply to existing and new sources within each category. "Categorical" pretreatment standards applicable to an industry on a nationwide basis are developed by EPA. In addition, another kind of pretreatment standard, "local limits," are developed by the POTW in order to assist the POTW in achieving the effluent limitations in its NPDES permit.

Regardless of whether a state is authorized to implement either the NPDES or the pretreatment program, if it develops its own program, it may enforce requirements more stringent than federal standards.

Those local governments who own and operate POTWs must meet the requirements for a pretreatment program under the Clean Water Act. In such situations, the local government becomes the regulator and establishes limits that must be met by those industries discharging to the POTW.

Spill Prevention, Control and Countermeasure Plans
The 1990 Oil Pollution Act requires that facilities that could reasonably be expected to discharge oil in harmful quantities prepare and implement more rigorous Spill Prevention Control and Countermeasure (SPCC) Plans required under the CWA (40 CFR §112.7). The SPCC regulations also require specific management procedures for loading, unloading, and storing petroleum products. The regulations specify criminal and civil penalties for deliberate or negligent spills of oil. Regulations covering response to oil discharges and contingency plans (40 CFR Part 300), and Facility Response Plans to oil discharges (40 CFR §112.20) and for PCB transformers and PCB-containing items were revised and finalized in 1995. Local governments who maintain fueling operations must comply with the SPCC regulations.

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