Methane's Hazardous Air Pollutant Status: What You Need To Know

Methane is a significant contributor to air pollution, particularly in the natural gas industry. In 2016, the US Environmental Protection Agency (EPA) introduced the Methane Rule, which aimed to curb methane emissions from new and modified sources in the oil and gas industry. This rule is expected to have substantial benefits for public health and the environment by reducing hazardous air pollutants (HAPs) and volatile organic compounds (VOCs), which are known to cause cancer, birth defects, and other serious health issues. While the focus is on methane emissions, the measures to control it also reduce HAPs and VOCs, improving air quality and mitigating climate change.

Methane is a hazardous air pollutant

Methane is a key component of natural gas, which is used for heating, cooking, and electricity generation. While natural gas is primarily composed of methane, it can also contain small amounts of other hydrocarbons, such as ethane, propane, and butane. These non-methane hydrocarbons include volatile organic compounds (VOCs), which are classified as ground-level ozone precursors, or smog.

When methane is leaked or vented from oil and gas equipment, it is released into the atmosphere along with co-pollutants such as VOCs and hazardous air pollutants (HAPs). HAPs, also known as air toxics, are substances known to cause cancer and other serious health issues, including reproductive problems and birth defects. Examples of HAPs include benzene, formaldehyde, and perchloroethylene, which is emitted from some dry cleaning facilities.

The U.S. Environmental Protection Agency (EPA) has recognized the dangers of methane pollution and has taken steps to regulate and reduce methane emissions. In 2016, the EPA finalized the first-ever nationwide limitations on methane pollution from new equipment in the oil and gas industry, known as the Methane Rule. This rule establishes specific control practices and quantifiable emission limits for various sources, including fracked oil and gas wells, compressors, and equipment leaks. The Methane Rule is expected to have significant benefits for public health and the environment, reducing not only methane emissions but also HAPs and VOCs.

In conclusion, methane is indeed a hazardous air pollutant that warrants strict regulation and mitigation efforts. By addressing methane pollution, we can improve air quality, protect public health, and combat the pressing issue of climate change.

EPA's Methane Rule

In December 2023, the US Environmental Protection Agency (EPA) announced its final rule regulating methane emissions from the oil and gas industry. The rule, known as the Methane Rule, aims to significantly reduce methane emissions, which are a major contributor to global warming and climate change.

The Methane Rule is an update to the EPA's new source performance standards for the oil and gas sector, issued under Section 111 of the Clean Air Act. It establishes specific control practices and quantifiable emission limits for various sources, including fracked and refracked oil and gas wells, compressors, pneumatic controllers, pumps, and equipment leaks at well sites and compressor stations. The rule also applies to older oil and gas infrastructure, such as wells, storage tanks, and compressor stations built before 2015, which were previously unregulated emission sources.

The EPA estimates that the Methane Rule will curb methane emissions by 510,000 tons by 2025 and will generate $690 million in climate benefits in that year alone. In addition, the rule is expected to reduce emissions of volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) by 210,000 tons and 3,900 tons, respectively. HAPs, such as benzene and formaldehyde, are known to cause cancer, brain damage, and birth defects, so the reduction in these pollutants will have significant public health benefits.

The Methane Rule is a critical component of the United States' efforts to reduce domestic greenhouse gas emissions and mitigate its contribution to global climate change. It is also a key step in inspiring other nations to take action on methane pollution, with several new countries joining the Global Methane Pledge during the first week of COP28. The rule includes both New Source Performance Standards for new sources and Emissions Guidelines to assist states in developing plans to cut methane emissions from existing sources.

The EPA has held trainings on the final rule for various stakeholders, including Tribes, tribal environmental professionals, small businesses, and the public. The Agency has also proposed revisions to address two narrow technical issues related to monitoring and emergency operations for flares that were included in the final rule. Overall, the EPA's Methane Rule is a significant step forward in the effort to reduce methane emissions and mitigate the impacts of climate change.

HAPs, VOCs, and other co-pollutants

Methane is a hazardous air pollutant (HAP) that is emitted alongside two categories of co-pollutants: volatile organic compounds (VOCs) and hazardous air pollutants (HAPs). HAPs are known to cause cancer and other serious health issues, such as reproductive effects and birth defects, and adverse environmental and ecological effects. They are regulated by the US Environmental Protection Agency (EPA) under the Clean Air Act, which requires the EPA to control 187 HAPs. The EPA has modified the list of HAPs through rulemaking and currently includes 188 pollutants. Examples of HAPs include benzene, formaldehyde, perchloroethylene, and methylene chloride.

VOCs are also considered HAPs and are known to have toxic effects on human health. They are often emitted from human-made sources such as cars, trucks, buses, factories, refineries, and power plants. VOCs interact with other chemicals in the atmosphere to form fine particulate matter, which can cause heart and lung ailments. Benzene, a VOC and HAP, has been classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC). Other VOCs of concern include chlorinated VOCs, trichloroethylene, tetrachloroethylene, and dichloromethane.

The EPA's Methane Rule, established in 2016, aims to curb methane emissions from the oil and gas industry by setting specific control practices and quantifiable emission limits for various sources, including fracked and re-fracked oil and gas wells, compressors, pneumatic controllers, and pumps. The Rule is expected to reduce methane emissions by 510,000 tons by 2025 and VOC and HAP emissions by 210,000 tons and 3,900 tons, respectively.

In addition to the Methane Rule, the EPA has also proposed updates to the new source performance standards for the oil and gas sector to further limit methane and VOC emissions from new and modified pollution sources. These updates are crucial for future efforts to reduce methane emissions from existing pollution sources in the oil and gas sector. The EPA estimates that the Methane Rule will generate $690 million in climate benefits alone in 2025, not including the significant public health benefits of reducing ozone, particulate matter, and HAP levels in the atmosphere.

Health and environmental impacts

Methane is a potent greenhouse gas that is accelerating short-term warming far more than carbon dioxide. It is the second most abundant greenhouse gas, and while it breaks down more quickly than carbon dioxide, it traps 80 times more heat. Methane has accounted for about 30% of climate change since pre-industrial times.

Methane emissions contribute to climate change, which has long been called a health emergency. Climate change drives extreme heat and extreme weather events like flooding, causing physical damage, injury, stress, and illness. Warmer temperatures and changing weather patterns increase the size and severity of wildfires, which produce dangerous smoke. These extreme weather events increase the risk of infectious diseases, heat-related illnesses, and deaths, while degrading water and air quality and reducing the availability of nutritious food.

Methane emissions also contribute to ground-level ozone, a dangerous air pollutant and precursor to smog. Ozone, in turn, causes or worsens breathing problems, heart disease, and strokes. It is formed when methane mixes with other toxic chemicals and gases, such as benzene, toluene, and xylene, which are released alongside methane or during the extraction of natural gas. These toxic chemicals worsen the health of people in nearby communities, especially in vulnerable communities near oil and gas operations.

Agriculture is a major source of methane emissions, with livestock emissions from manure and gastroenteric releases accounting for about one-quarter to one-third of human-caused methane emissions. Paddy rice cultivation accounts for another 8% of human-linked emissions. Improving animal health and better managing manure can help reduce methane emissions and improve air quality.

The oil and gas industry is another major source of methane emissions, with about a quarter of global methane emissions coming from methane leaks across the oil and gas supply chain. In 2021, the EPA proposed new rules to mitigate harmful methane and hazardous air pollutant emissions from the oil and gas industry, which are expected to generate significant climate and health benefits. However, some argue that these rules do not go far enough to protect the health of communities near oil and gas operations.

Reducing methane emissions

Methane is a hazardous air pollutant that contributes to the production of tropospheric ozone, which causes about a million premature respiratory deaths globally. It is second only to carbon dioxide in driving climate change. As such, reducing methane emissions is crucial.

The oil and gas industry is the largest source of methane emissions from the fossil fuels sector. To reduce methane emissions from this sector, the US Environmental Protection Agency (EPA) has implemented the Methane Rule, which establishes specific control practices and quantifiable emission limits for various sources, including fracked and re-fracked oil and gas wells, compressors, pneumatic controllers, pumps, and equipment leaks at well sites and compressor stations. The rule aims to curb harmful methane pollution from the oil and gas industry and reduce domestic greenhouse gas emissions.

Another way to reduce methane emissions from the oil and gas industry is by addressing flaring and venting reduction and tackling fugitive methane emissions. Flaring is the process of burning off excess gas released during oil and gas production. By improving flare efficiency and ensuring flares are always lit, methane emissions can be reduced. Additionally, detecting and measuring methane leaks accurately is essential for effective leak detection and repair (LDAR) operations.

Agriculture is another significant source of methane emissions, responsible for about 40% of global methane emissions. Livestock manure management is one area where methane emissions can be reduced. By switching from liquid manure management systems, which lead to anaerobic conditions and increased methane production, to practices that manage manure in drier, aerobic conditions, methane emissions can be significantly reduced.

Overall, reducing methane emissions is crucial in mitigating climate change and improving public health. By implementing regulations, improving technology, and adopting better practices in the oil and gas industry and agriculture, significant reductions in methane emissions can be achieved.

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