Air Pollution Crisis: Epa Standards Violated

The Clean Air Act (CAA) requires the Environmental Protection Agency (EPA) to set National Ambient Air Quality Standards (NAAQS) for six common air pollutants. These pollutants are carbon monoxide, ground-level ozone, lead, nitrogen oxides, particulate matter, and sulfur dioxide. The EPA designates areas as meeting (attainment) or not meeting (nonattainment) these standards. Nonattainment areas must develop plans to attain the NAAQS, and failure to do so by the target date can result in penalties, including the withholding of federal highway funds. The Clean Air Act also establishes two types of national air quality standards: primary standards, which protect public health, and secondary standards, which protect public welfare. The EPA is responsible for reviewing and revising the NAAQS at five-year intervals to ensure they are based on the most recent scientific findings.

Clean Air Act and National Ambient Air Quality Standards (NAAQS)

The Clean Air Act (CAA) is a federal law that regulates air emissions from stationary and mobile sources. The Act requires the Environmental Protection Agency (EPA) to set National Ambient Air Quality Standards (NAAQS) for six common air pollutants, or "criteria pollutants", that are harmful to public health and the environment. These pollutants are carbon monoxide, ground-level ozone, lead, nitrogen oxides, particulate matter, and sulfur dioxide.

The Clean Air Act Amendments of 1970 established two types of national air quality standards: primary standards, designed to protect public health, and secondary standards, designed to protect public welfare from adverse effects, including those related to damage to soils, water, crops, vegetation, man-made materials, animals, wildlife, weather, visibility, and climate, as well as transportation hazards, economic values, and personal comfort and well-being. The EPA must designate areas as meeting (attainment) or not meeting (nonattainment) the standard.

States are required to develop plans to attain and maintain the NAAQS, in both general and specific terms. The Clean Air Act also requires the EPA to review the standards and the science behind them periodically to determine whether changes are warranted. The most recent amendments to the Clean Air Act were made in 1990, which primarily set new goals (dates) for achieving attainment of NAAQS, as many areas of the country had failed to meet the deadlines.

The EPA's NAAQS review process involves a comprehensive review of the relevant scientific literature, which is summarised in the Integrated Science Assessment (ISA). Based on the ISA, the EPA performs a risk and exposure assessment, which is summarised in the Risk and Exposure Assessment (REA) document. The third document, the Policy Assessment (PA), integrates the findings and conclusions of the ISA and REA into a policy context and provides lines of reasoning that could be used to support the retention or revision of the existing NAAQS. Each of these three documents is released for public comment and peer review by the Clean Air Scientific Advisory Committee (CASAC), a sub-committee of the EPA's Science Advisory Board. Once all three documents are finalised, they are given to the EPA Administrator to use in selecting a proposed NAAQS, which is released through the Federal Register for public comment. The Administrator then considers the comments received and makes changes to the proposed NAAQS if necessary before publishing the final NAAQS in the Federal Register.

Nonattainment areas and state implementation plans

The Clean Air Act (CAA) requires the EPA to set National Ambient Air Quality Standards (NAAQS) for six common air pollutants. These pollutants are carbon monoxide, ground-level ozone, lead, nitrogen oxides, particulate matter, and sulfur dioxide. The EPA must then designate areas as meeting (attainment) or not meeting (nonattainment) these standards.

When an area is designated as nonattainment, the state is required to develop a State Implementation Plan (SIP) to attain and maintain the NAAQS in that area. The SIP outlines specific actions and enforceable measures to improve air quality and bring the area back into compliance with federal standards within a specific time frame. These measures may include a combination of state, local, and federal rules, plans, administrative orders, and permits for specific sources. The SIP is developed in collaboration with local clean air agencies and affected communities.

The Clean Air Act was amended in 1977 and 1990 to set new goals and deadlines for achieving NAAQS, as many areas of the country had failed to meet the initial deadlines. The 1990 amendments also introduced technology-based standards for "major sources" and certain "area sources" of hazardous air pollutants. Major sources are defined as stationary sources that emit or have the potential to emit 10 tons or more of a hazardous air pollutant per year.

Nonattainment areas are required to develop plans that meet specific requirements depending on the severity of the pollution problem. These plans may include a range of strategies, such as implementing best available control technologies, emissions reduction programs, and other measures to improve air quality. The EPA provides guidance and support to states in developing and implementing these plans, and works with local agencies and communities to ensure effective and timely attainment of the NAAQS.

Criteria air pollutants

The Clean Air Act (CAA) requires the Environmental Protection Agency (EPA) to set National Ambient Air Quality Standards (NAAQS) for six common air pollutants. These pollutants are known as criteria air pollutants and are found all over the US. They can harm your health, the environment, and cause property damage. The six criteria air pollutants are:

• Carbon Monoxide
• Ground-level Ozone
• Lead
• Nitrogen Oxides
• Particulate Matter
• Sulfur Dioxide

The Clean Air Act requires all areas of the country to meet or strive to comply with the NAAQS. The EPA designates areas as meeting (attainment) or not meeting (nonattainment) the standard. States are required to develop a general plan to attain and maintain the NAAQS in all areas of the country and a specific plan to attain the standards for each area designated as nonattainment. One of the key programs designed to achieve compliance with the NAAQS is the New Source Review (NSR) program, a preconstruction review process for new and modified stationary sources. The Act was amended in 1977 and 1990 to set new goals (dates) for achieving attainment of NAAQS since many areas of the country had failed to meet the deadlines.

Health and environmental effects

Air pollution has significant health and environmental effects. It contributes to a range of respiratory and cardiovascular issues, with vulnerable populations, such as the elderly, children, and those with pre-existing health conditions, being particularly at risk.

EPA's NAAQS review process

The EPA's NAAQS review process has evolved over time, with the Agency making changes to improve efficiency and ensure decisions are informed by the best available science. The Clean Air Act (CAA) requires the EPA to set National Ambient Air Quality Standards (NAAQS) for six principal outdoor air pollutants, known as "criteria pollutants", which are harmful to public health and the environment. These pollutants are carbon monoxide, ground-level ozone, lead, nitrogen oxides, particulate matter, and sulfur dioxide.

The NAAQS review process consists of several key steps. Firstly, the Integrated Science Assessment (ISA) is a comprehensive evaluation of policy-relevant science, including key judgments that inform the development of risk and exposure assessments. The ISA is followed by the Risk/Exposure Assessment (REA), which uses information from the ISA to quantify exposures and risks to human health or the environment associated with air quality conditions. The Policy Assessment (PA) then provides a transparent analysis of the scientific basis for alternative policy options, informing the decisions of senior EPA management. The PA also facilitates the Clean Air Scientific Advisory Committee's (CASAC) advice and recommendations to the Agency and Administrator.

The EPA has modified the NAAQS review process over the years, incorporating feedback from stakeholders and the public. In 2005, the EPA Deputy Administrator requested a comprehensive review of the NAAQS setting and reviewing process, resulting in a report with conclusions and recommendations in 2006. The EPA also held a public workshop in June 2006 to discuss the NAAQS process, providing an opportunity for public engagement and input.

In 2007, the EPA further revised the process to include review and advice from the CASAC on the second draft risk/exposure assessment reports. These changes aimed to improve efficiency and ensure that decisions are based on robust scientific evidence. The NAAQS review process continues to evolve, with Administrator Lisa P. Jackson calling for additional key changes in 2009, including reinstating a Policy Assessment document to bridge the gap between scientific information and administrative judgments.

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