Willer Nature Gazette #6: FUGITIVE EMISSIONS
The nature of fugitive emissions makes them hard to assess & their level is significant-around 5% of global emissions and has probably increased in recent years
The IPCC defines fugitive emissions as “emissions [of greenhouse gases] that are not produced intentionally by a stack or vent” and stipulates that they may “include leaks from industrial plants and pipelines” (IPCC, 2006). A previous definition provides more detail on potential sources of fugitive emissions: “they may be caused by the production, processing, transmission, storage and use of fuels and include combustion emissions only if they do not meet production needs (e.g. natural gas flaring at gas and oil production facilities) “(IPCC, 1996).
Accordingly, there is no stable and universal definition of fugitive emissions. In practice, they generally include accidental emissions (pipeline breakage, coal seam fire, etc.), leaks and diffuse escapes (defective valves or seals, migration of gas to the surface near wells or mines, emissions from abandoned wells, etc.) and unintentional but non-productive discharges (mine ventilation, flaring, degassing, etc.). Many phenomena are therefore involved in a primarily negative category: fugitive emissions are ultimately emissions related to human activities that do not fit into any other category.
This definition may vary from one sector to another. In the fossil fuel sector, fugitive emissions are sometimes broadly defined as any emissions unrelated to the end use of the fuel. In air pollution, a fugitive emission can be defined as the “release of pollutants into the free atmosphere after they have escaped an attempt to capture them with a hood, seal or any other means for ensuring the capture and retention of these pollutants”. They, therefore, contrast with channelled emissions (CITEPA, 1999).
Most occurrences of fugitive emissions are less, of no immediate impact, and not easy to detect. Nevertheless, due to rapidly expanding activity, even the most strictly regulated gases have accumulated outside the industrial workings to reach measurable levels globally. Fugitive emissions include many poorly understood pathways by which the most potent and long-lived ozone-depleting substances and greenhouse gases enter Earth's atmosphere.
Major Sources, Problems & Regulations?
Even if the data are incomplete, it is possible to identify some activities that contribute significantly to fugitive emissions: gas flaring, the hydrocarbon logistics chain, dust, fine particles, aerosols and the coal supply chain. Among these, the most environmentally impactful fugitive emissions are greenhouse gases, such as refrigerants and methane.
Types of Fugitive Emissions-
? Dust
Dust, or fine particles of soil and other organic material, is unintentionally released from driving on unpaved roads, tilling agricultural fields, and heavy construction operations. Once kicked up, dust can contribute to air pollution. Fugitive dust can cause people to have difficulty breathing, chronic respiratory illness, and lung disease. It can also increase the risk of traffic accidents due to reductions in visibility and reduce agricultural productivity by shielding sunlight. In the United States, the arid and semi-arid areas in the southwest are especially at risk of releasing fugitive dust from ongoing development.
Many development projects are required to go through the National Environmental Policy Act, or NEPA, which includes an assessment of a project's anticipated air quality impacts. If a project is expected to have "significant" impacts on air quality, such as through the fugitive release of dust, measures to mitigate the effects may be required by the EPA. Some states, like California, have an additional environmental review process that applies air quality standards to certain projects, including projects not required to go through the NEPA process. These air quality regulations include measures to reduce the risk of fugitive emissions.
On construction sites, manage it by frequently wetting unpaved areas. When wet, fine particles on the ground are too heavy to be kicked up during the operation of construction machinery. In agriculture, reduce it by planting cover crops, irrigation, reducing the frequency of tilling, and combining tractor operations.
? CFCs
Various types of chlorofluorocarbons, or CFCs, were commonly used in the 20th century as refrigerants. The US banned CFC production in many countries in the 1990s. However, the accidental release of these environmentally damaging chemicals continues today from the ongoing use of CFCs in outdated equipment and the use of recycled CFCs in fire suppression systems. In 2012, there was an unexpected and persistent increase in global emissions of one particular type of CFC, CFC-11, which contributes a quarter of all ozone-depleting chlorine that reaches the stratosphere. International efforts to reduce the fugitive release of CFCs led to rapid declines in atmospheric CFCs in 2019 and 2020.7
Once, refrigerators and air conditioners are made with several chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs). After discovering that these aerosols were putting holes in Earth's ozone layer, the international ratification of the Montreal Protocol in 1988 and amendments to the Clean Air Act in 1990 phased out the use of these and other environmentally damaging chemicals. Hydrofluorocarbons (HFCs) and perfluorocarbons (PFCs) are used today instead.
Similarly, for fire suppression, halon was once commonly used. However, halon also has an ozone-depleting effect. The EPA began phasing out the production and import of new halon in 1994. In 1998, they banned Halon blends. Today, only recycled halon come in use for specific fire suppression applications, such as on aircraft and oil and gas exploration operations. The EPA only allows the release of halon during the testing, maintenance, and repair of halon-containing equipment. The EPA is authorized to levy heavy fines against those who release halon and other ozone-depleting substances accidentally or without EPA authorization.
While there is a ban on producing many ozone-depleting substances and several other countries, old products containing these greenhouse gases remain in refrigerators and air conditioning units. As these decades-old equipment deteriorate, the CFCs they often release as fugitive emissions. One of these ozone-depleting substances, CFC-12, traps nearly 11,000 times the heat of carbon dioxide. Given the environmental hazard created by these old, often forgotten refrigerants, the recycling of old CFCs is now a part of the carbon-offset market: people can exchange their old refrigerants for money.
In the United States, carbon offset markets are expected to continue filling some of the gaps in the regulation of CFC fugitive emissions by incentivizing the removal of now-banned greenhouse gases. However, carbon offset projects must wait for credits to sell to make a return on investment. For developing countries, the need for capital upfront may be a barrier to implementing effective carbon offset programs for CFCs.
? Ethylene Oxide
Ethylene oxide is used to manufacture a variety of chemicals, like plastics, textiles, and antifreeze, and is used to sterilize foods, spices, and medical equipment. Since the 1980s, ethylene oxide is known to cause cancer in animals based on studies conducted on mice and rats. It is considered to be a known carcinogen by the US EPA and the CDC. During a recent review of hazardous emissions, the EPA found the fugitive release of ethylene oxide to be a significant driver of unacceptable health risks resulting from all hazardous air pollutants in the United States.
State regulations of fugitive ethylene oxide emissions continue to expand as the public becomes more aware of the health risks associated with the chemical. For example, Illinois passed two new laws regulating ethylene oxide in 2019 making the state's ethylene oxide emissions standards the strictest in the country. Similarly, Georgia is working with sterilization facilities to implement voluntary reductions in ethylene oxide emissions. Meanwhile, the state of Texas took its ethylene oxide legislation in the opposite direction by increasing the allowable limit from 1 part per billion (ppb) to 2.4 ppb in 2020.
? FLARING OF NATURAL GAS
Gas flaring involves burning gas without using the heat produced. This operation makes it easy to get rid of combustible gases from oil extraction or refining but releases carbon dioxide. By convention, flaring-related emissions are considered fugitive emissions. Last year, 140.57 billion cubic metres of gas were flared, equivalent to 3% of worldwide natural gas production. This practice decreased in 2017 for the first time since 2010: gas flaring volume dropped by around 5% despite an increase in world oil production of 0.5% (World Bank, 2018). Flaring, however, remains responsible for the emission of 300 million tonnes of CO2 per year.
Despite this progress, flaring remains common, especially in countries that do not have a market or infrastructure for the sale of gas. Its use is therefore often linked to the development and stability of the region: in Yemen, for example, the volume of gas flared per barrel of oil produced has increased four-fold between 2013 and 2017, while in Syria it has increased ten-fold (World Bank). To limit this practice, the World Bank has launched a “Zero routine flaring” initiative that is mobilising oil tankers and governments to eliminate flaring in the normal operation of facilities by 2030.?
Flaring also has consequences for the local environment (air pollution, noise, etc.), which is why communities are mobilising to end the practice, often with the support of NGOs. In 2015, for example, Nigerian representatives of the Egi communities participated in Total’s general assembly to demand the cessation of flaring in the Niger Delta and to testify to the environmental and social problems caused by the exploitation of hydrocarbons. They were supported by the NGO Friends of the Earth (Novethic, 2015). In 2017, Total Exploration and Production Nigeria signed 2 agreements with the Egi community to improve the living conditions of those living near its facilities.
? UPSTREAM GAS AND OIL
Oil and gas wells are a substantial source of fugitive emissions. In 2018, a natural gas well in Ohio operated by a subsidiary of ExxonMobil leaked millions of cubic feet of methane into the atmosphere over twenty days. This massive release of fugitive emissions was detected by a satellite's routine global survey. The first such leak to be detected using satellite technology.
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In addition to flaring, the hydrocarbon sector is responsible for fugitive emissions of methane at all stages of its activity:
? Wells: methane is piped and recovered through the casing & some can escape into the atmosphere through the soil around the boreholes (Kang, 2014). These diffuse discharges can last a decade after the end of operations (Boothroyd, 2016), Additional fugitive emissions come from abandoned wells. The abandoned and uncapped wells are also known to release methane into the atmosphere well after they close.
? During gas transportation and storage: defective sealing of valves and fittings, breaks and leaks, intentional or uncontrolled degassing, etc.
? During the processing of petroleum products: a refinery has tens of thousands of valves that can leak small amounts of greenhouse gases or other pollutants.
The solutions available for reducing these fugitive emissions depend on their source but require the mobilisation of companies involved in the hydrocarbon logistics chain. Apart from the major leaks and those that represent a risk to staff, reducing fugitive emissions is not always economically profitable. Indeed, detecting leaks, determining their source and correcting them requires investments that may be much higher than the cost of the lost gas.
Local regulation and the actions of communities and NGOs can play a huge role in encouraging businesses to respond to low-volume leaks. For example, BP has installed a leak detection and repair system on more than 80,000 valves at its refinery in Whiting & Indiana. An agreement was needed to bind the company with the American justice system at the end of a procedure initiated by 3 American states (Indiana vs. BP, 2001).?
Also, on 23 March 2017, California adopted a new regulation on methane emissions in the hydrocarbon sector, expected to reduce emissions of the state by 1.4 CO2mteq per year by establishing quarterly monitoring of fugitive emissions and imposing repair timescales when leaks occur.
Cooperation between companies, researchers and public bodies at the sub-national level is necessary. At the world level, the objective of the Oil and Gas Methane Partnership, under the auspices of the Climate and Clean Air Coalition, is to encourage oil tankers to take voluntary action. Ten of the largest oil companies, including Royal Dutch Shell, Total and BP, PEMEX of Mexico and PPT of Thailand, have ratified their guiding principles for reducing methane emissions in the gas industry.?
Methane leaks are common due to the world's shift from coal to natural gas, the latter of which produces fewer greenhouse gas emissions when burned. However, the accidental release of methane during natural gas extraction may counteract natural gas's emissions advantage over coal.
According to a 2018 report published by Climate Chance, the oil and gas industry is the primary producer of fugitive emissions. The report also found the United States to be the second-largest producer of fugitive emissions of the 10 countries analyzed.?
Also, additional satellites are scheduled for launch in the coming years to bolster global monitoring of fugitive emissions from the oil and gas industry. According to the Environmental Defense Fund (EDF), which launched a new methane-monitoring satellite in 2022, fugitive emissions from the oil and gas industry are up to 60% higher than what the EPA found.
? THE COAL SECTOR
?After hydrocarbons, the next sector causing fugitive emissions is coal. Like oil reservoirs, coal seams generally contain methane that can escape into the atmosphere when we exploit the resources.?Coal-related fugitive emissions mainly occur:?
? During coal mining: the fracturing of the ore releases trapped methane. In an open-cast mine, the gas occurs directly in the atmosphere. When the mine is underground, the methane spreads in the tunnels before being evacuated by the ventilation system. The methane concentration in the ventilated air outside mines is usually a few tenths of a per cent, while the risk of explosion (“firedamp”) starts from a few per cent.
? During the transportation and storage of coal, the gas is released into atmosphere that is still present in the ore.?
? Following decommissioning: methane can escape through cracks and wells created during operation. In the United States, for example, there are several thousand abandoned mines, including 400 identified as discharging significant quantities of methane (EPA, 2017).
According to the available inventories, most emissions occur during ore extraction: ventilated methane alone accounts for half of the sector’s fugitive emissions (EPA).?
The gas associated with coal can be recovered and used as natural gas for electricity generation, vehicle fuel or in petrochemical processes. It can also be used in mining: to dry ores, heat tunnels, etc. Fugitive emissions reduction in the coal sector can thus be a profitable operation in Europe coal degassing would yield €1.8 - €2.2 per tonne of CO2 equivalent avoided (Ecofys, 2009). However, these emissions are often neglected in the ETS framework, the European carbon market, for example, they are not included in calculations of the carbon footprint of coal producers.?
The Global Methane Initiative, a public-private partnership launched in 2004 to reduce methane emissions, identified nearly 200 projects in the coal sector in 2016 (Global Methane, 2016). Among the most recent is the installation of a 1MW gas turbine (with the option to extend to 6MW) in the Fuhong underground mine in China or gas recovery and use for the production of steam, heat and electricity at the Severnaya mine in Russia.?
Monitoring Requirements for Fugitive Emissions
The EPA requires certain entities, like active oil wells and compressor stations, to perform semi-annual or annual tests for fugitive emissions. Once the EPA discovers a fugitive emissions source, it demands to repair and stop the emission within 30 days. In 2020, the EPA eliminated monitoring requirements for "low production" well sites — those producing less than 15 barrels per day. Restrictions are reduced on incidental methane emissions, which even oil industry proponents criticized.
The EPA similarly regulates the unintentional release of ethylene oxide. However, in 2016, the EPA increased allowable exposure levels by nearly 50-fold. In 2018, research on a Michigan sterilization facility found local ethylene oxide levels to be 100 times the EPA's 2016 limit and 1500 times the State's limit. The study concluded that uncaptured fugitive emissions largely caused high ethylene oxide exposure levels.
By order of the State of Michigan's Department of Environment, Great Lakes, and Energy (EGLE), the facility was forced to stop using ethylene oxide by January 2020 and pay a $110,000 penalty to the State of Michigan.
CONCLUSION
Despite a significant contribution, fugitive emissions are one of the blind spots in combating climate change. For better evaluation and reduction of fugitive emissions, much work is needed. The available information suggests that extraction and, to a lesser extent the processing and transportation, of fossil fuels, is the main source of fugitive emissions.?
As emissions continue beyond the end of operations, site remediation and the attention of local authorities can also help to reduce emissions. Responsibility for their reduction, therefore, rests first and foremost in the oil, gas and coal companies, assisted - sometimes spurred - by other actors: researchers, local authorities and local communities, and NGOs...