Under this law, the EPA sets limits on how much of a pollutant can be in the air anywhere in the United States. States are not allowed to have weaker pollution controls than those set for the whole country.
The law recognizes that states should lead in carrying out the Clean Air Act, because pollution control problems often require special understanding of local industries, geography, housing patterns, etc.
States must develop state implementation plans (SIPs) that explain how each state enforces the Clean Air Act. A state implementation plan is a collection of the regulations a state will use to clean up polluted areas. The states are obligated to notify the public of these plans, through hearings that offer opportunities to comment, in the development of each state implementation plan.
EPA must approve each SIP, and if an SIP isn't acceptable, EPA can take over enforcing the Clean Air Act in that state.
These permits are known as ‘part 70’ permits because they are related to the federal requirements in 40 CFR part 70. These permits are also known as ‘title V’ permits because they are required by Title V of the 1990 Clean Air Act. The title V permit is meant to contain all the requirements for emissions from the permitted source. The permit requires reporting, monitoring, and annual certification of compliance, all of which is public information.
The permit information is available online through the EPA ECHO (Enforcement and Compliance History Online) database and the permits themselves are available online through the websites of various state agencies or EPA regional offices.
The Clean Air Act requires that States with heavy air pollution use oxygenated gasoline. This is known as the "Clean Fuel Requirement" because oxygenated gasoline produces less air pollution than regular gasoline for older vehicles which use a carburetor. It is often wrongly thought that newer vehicles, which use fuel injection and closed loop fuel control, also benefit from the use of oxygenated fuels. However, this is simply not the case.
The program is intended to identify and repair components such as valves, pumps, compressors, flanges, connectors and other components that may be leaking. These components are the main source of the fugitive VOC emissions.
Testing is done manually using a portable vapor analyzer that read in parts per million (ppm). Monitoring frequency, and the leak threshold, is determined by various factors such as the type of component being tested and the chemical running through the line. Moving components such as pumps and agitators are monitored more frequently than non-moving components such as flanges and screwed connectors. The regulations require that when a leak is detected the component be repaired within a set amount of days. Most facilities get 5 days for an initial repair attempt with no more than 15 days for a complete repair. Allowances for delaying the repairs beyond the allowed time are made for some components where repairing the component requires shutting process equipment down.