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Oil and natural gas pollution

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Pollution includes contaminants in the air, in water, or on land. This article focuses on the pollution that can result from producing, distributing, and/or using oil, and natural gas as well as the equipment and procedures adopted by the oil and gas industry to prevent pollution. Natural environments and human health can be negatively affected by pollutants released during energy production and use depending on the level of chemicals or pollutants released. The most common forms of oil and gas pollution are air and water pollution, which can occur at any stage of production or use. Oil and natural gas do not produce the same kind of pollutants, and some of these pollutants can be more toxic than others.[1]

A map of oil and natural gas well counts across the United States

Background

Toxicity

Toxicity refers to the ability of certain materials to cause harm or death to a living organism. In sufficient amounts, any chemical can be toxic. For example, water intoxication occurs when an individual drinks too much water too quickly. The individual's kidneys cannot process the large amount of water, resulting in death. Thus, toxicity depends on the dose or amount of a chemical to which an organism has been subjected. The same dose of a chemical can affect different people in different ways depending on the person's genetics, weight, age, and gender. The presence of some chemicals is measured by their concentration in the air or water. Chemical concentrations can be measured in parts per million (ppm), parts per billion (ppb), and parts per trillion (ppt).[2][3][4][5][6][7]

Types of pollution

Air

Natural gas production and distribution

Air pollutants result from burning oil and natural gas. In addition, pollutants can leak out of storage tanks during oil and gas production and distribution. Different kinds of oil emit different amounts of a pollutant depending on the oil's content. For example, when oil is burned for electricity, sulfur dioxide, mercury compounds, and nitrogen oxides are produced. On average, 12 pounds of sulfur dioxide, and four pounds of nitrogen oxides are emitted per megawatt hour of electricity generated from burning oil.[8]

Natural gas has fewer impurities than petroleum or oil. For example, natural gas releases fewer sulfur dioxide and nitrogen oxide emissions compared to oil. Natural gas is composed primarily of methane, a colorless, odorless, nontoxic, and flammable gas that is the main component of natural gas. Methane can also leak from storage tanks. Natural gas-fired energy generation emits 0.1 pounds of sulfur dioxide per megawatt hour (MWh) and 1.7 pounds of nitrogen oxide per MWh.[9][10]

Natural gas pipelines

Other air pollutants released by oil and natural gas include the following:[11]

  • Volatile organic compounds (VOCs) include benzene, formaldehyde, and other toxic substances. They combine with nitrogen oxides to create ground-level ozone, commonly known as smog. Benzene can cause cancer at high levels of exposure.
  • Hydrogen sulfide (H2S) is released by flaring and venting diesel fuel or natural gas. It is harmful at low levels and can be fatal at higher levels.
  • Polycyclic aromatic hydrocarbons (PAHs) are found in oil and gas formations and are produced when they are burned. PAHs include over 100 chemicals, some of which are found in coal tar and oil. Some PAHs are used to make plastics, dyes, and pesticides.
  • Particulate matter is released by dust, exhaust, and other air emissions. Smaller particles can get lodged in the lungs and lead to potential health problems.

Air pollution can be emitted during different stages of oil and gas development, including the following:[12]

  • Condensate tanks are used to store hydrocarbons that change from gas to liquid during natural gas production. The U.S. Occupational Safety and Health Administration (OSHA) set maximum exposure levels of benzene for oil and gas workers at 1 ppm (part per-million) over an eight-hour period.
  • Engines, including diesel-powered and gasoline engines, are used to power oil and gas production during drilling, trucking, and oil rig work. Exhaust emissions from burning gasoline and diesel fuels include nitrogen oxides and carbon monoxide.
  • Gas leaks occur when seals, tubing, or pipelines crack or break or when caps and lids on equipment are not sufficiently tightened. Gas leaks release methane and volatile organic compounds (VOCs) into the air.
  • Pits are used to store the produced water, wastewater, and flowback left after natural gas has been extracted. This contaminated water is stored in pits can emit air pollution depending on the kind of waste injected into a pit. Benzene, hydrogen sulfide, and VOCs can be released into the air from pits with certain wastes.[13][14]
U.S. methane emissions by source, 2012 (click to enlarge)

Criteria pollutants

The table below presents national estimates of pollutants regulated under the National Ambient Air Quality Standards (as well as pollutants such as particulate matter, which contributes to ozone formation) between 1980 and 2013. During that period, criteria pollutant emissions declined by approximately 64.7 percent.[15]

National emissions estimates for common pollutants in millions of tons (1980-2013)
Pollutant 1980 1985 1990 1995 2000 2005 2013 Percent change, 1980-2013
Carbon monoxide (CO) 178 170 144 120 102 81 59 -66.85%
Lead 0.074 0.023 0.005 0.004 0.002 0.001 0.001 -98.65%
Nitrogen oxides (NOx) 27 26 25 25 22 20 13 -51.85%
Volatile organic compounds (VOC) 30 27 23 22 17 16 14 -53.33%
Particulate matter (PM10 and PM2.5) 6 4 5 5 6 7 5 -16.67%
Sulfur dioxide (SO2) 26 23 23 19 16 14 5 -80.77%
Total 267 250 218 189 160 135 94 -64.79%
Source: U.S. Environmental Protection Agency, "Air Quality Trends (1980-2013)"

Water

Oil spills

The Deepwater Horizon offshore drilling unit in the Gulf of Mexico.

Oil can spill from tankers during accidents. In 1989, the Exxon Valdez tanker spilled nearly 10.8 million gallons of oil near Alaska's shoreline. Local, state, and federal agencies supervised the cleanup. Twenty-eight different types of animals, plants, and aquatic habitats in Alaska's Prince William Sound were affected by the spill. The Exxon Valdez incident was the biggest oil spill in the United States until April 2010, when an explosion on the Deepwater Horizon oil well off the Gulf Coast resulted in an oil spill that released millions of barrels of oil into the Gulf of Mexico. The National Oceanic Atmospheric Administration (NOAA) commenced the federal government's emergency response. The spill affected the coasts of Louisiana, Mississippi, Texas, Alabama, and Florida.[16][17]

Drinking water sources

An example of a fracking wastewater pond

Natural gas development can pollute drinking water sources during drilling, fracking, refining, or disposing of waste water without measures to protect water resources. Methane and other gases can leak into drinking water sources, and though methane is not linked to serious health effects, it is flammable and can combust at levels of 5 percent or more. Methane and volatile organic chemicals (VOCs) can seep into groundwater sources near natural gas wells if the wells are poorly constructed or broken. Groundwater and surface water can also be impacted by surface leaks or if fracking fluid is spilled. State and federal regulations cover all produced water, flowback, and refinery waste. Produced water and flowback are regulated under the Resource Conservation and Recovery Act (RCRA).[18][19][18]

2016 EPA study on fracking

On December 13, 2016, the Environmental Protection Agency (EPA) released a final report requested by Congress in 2010 on the impact of hydraulic fracturing (fracking) on drinking water resources. The EPA report stated that there was "scientific evidence that hydraulic fracturing activities can impact drinking water resources in the United States under some circumstances." An earlier draft version of the report, released in June 2015, concluded that fracking had not created any widespread or systemic impact on drinking water. That conclusion was deleted in its final version, which argued that "fracking could impact drinking water throughout the drilling process."[20] According to the report, the agency based its study on 1,200 scientific sources, peer review by the EPA's Science Advisory Board, and the input from federal, state, local, tribal, and industry officials.[21][22] However, the EPA acknowledged that its findings were limited in scope, reporting that "uncertainties and data gaps limited the EPA's ability to fully assess impacts to drinking water resources both locally and nationally."

The December 2016 report is a finalized version of an interim report issued by the EPA in 2015, in which the agency "did not find evidence that these mechanisms have led to widespread, systemic impacts on drinking water resources in the United States." To read more about the interim report, click here.

Findings

The EPA concluded in some circumstances that poorly constructed drilling wells and incorrect wastewater management affected drinking water resources, particularly near drilling sites. According to the report, effects on drinking water "ranged in severity, from temporary changes in water quality to contamination that made private drinking wells unusable." Instances where drinking water resources were more vulnerable included the following:

“
  • Water withdrawals for hydraulic fracturing in times or areas of low water availability, particularly in areas with limited or declining groundwater resources;
  • Spills during the management of hydraulic fracturing fluids and chemicals or produced water that result in large volumes or high concentrations of chemicals reaching groundwater resources;
  • Injection of hydraulic fracturing fluids into wells with inadequate mechanical integrity, allowing gases or liquids to move to groundwater resources;
  • Injection of hydraulic fracturing fluids directly into groundwater resources;
  • Discharge of inadequately treated hydraulic fracturing wastewater to surface water resources; and
  • Disposal or storage of hydraulic fracturing wastewater in unlined pits, resulting in contamination of groundwater resources.[23]
 ”
—Environmental Protection Agency[21]

The report focused on the potential impact on these water sources during five stages of the fracking process:[21][22]

  • The acquisition of water to be used for fracking
  • The mixing of chemical additives and water to make fracking fluids
  • The injection of fracking fluids into a production well to create and enlarge fractures in the targeted production zone.
  • The collection of wastewater that returns through a well after the injection of fracking fluids
  • The management of wastewater through disposal or reuse.
Reactions
  • The American Petroleum Institute (API), which represents the oil and natural gas industry, criticized the EPA report as misleading. "It is beyond absurd for the administration to reverse course on its way out the door. The agency has walked away from nearly a thousand sources of information from published papers, technical reports and peer reviewed scientific reports demonstrating that industry practices, industry trends, and regulatory programs protect water resources at every step of the hydraulic fracturing process. Decisions like this amplify the public's frustrations with Washington," said API Upstream Director Erik Milito. Milito further stated, "Fortunately, the science and data clearly demonstrate that hydraulic fracturing does not lead to widespread, systemic impacts to drinking water resources. Unfortunately, consumers have witnessed five years and millions of dollars expended only to see conclusion based in science changed to a conclusion based in political ambiguity."[24]
  • Energy in Depth, a website established by the Independent Petroleum Association of America, an oil and gas industry group, endorsed the EPA's conclusion, which it argues reinforces its view that there is no systematic impact from fracking, but also criticized the EPA's role in the report. A spokesperson for the website said, "EPA’s report blows apart the anti-fracking campaign’s most common claim, namely that hydraulic fracturing is polluting groundwater all across America" but that the "EPA did its best to inject politics into this good news by inflating concerns about groundwater, no doubt as a parting thank-you gift to the ‘Keep It In the Ground’ movement." The Keep It In the Ground movement refers to a collection of individuals, legislators, and organizations that oppose future oil and natural gas drilling.[20][25]
  • Food & Water Watch, an environmental group that opposes fracking, said the report confirmed its view that fracking contaminates drinking water. According to the group's executive director, "The EPA has confirmed what we’ve known all along: fracking can and does contaminate drinking water. We are pleased that the agency has acted on the recommendations of its Science Advisory Board and chosen [sic] be frank about the inherent harms and hazards of fracking. Today the Obama administration has rightly prioritized facts and science, and put public health and environmental protection over the profit-driven interests of the oil and gas industry."[26]
  • The Sierra Club, an environmental group that opposes fracking, said the report confirmed its view that fracking negatively affects drinking water. According to the group's official statement, "The Sierra Club applauds the EPA for its science-based fracking report, confirming what so many already knew; fracking presents a clear and present threat to our water, our public health, and our communities. For far too long, communities around the country have faced the daily threat of contaminated water, earthquakes, and an uncertain future due to fracking, all while oil and gas companies peddled the false claim that the process was safe. Today’s report ends this charade. No longer will families be told a lie as their health and safety are threatened."[27]
An aerial view of oil and gas wells in Texas

Regulation of fracking

The Safe Drinking Water Act of 1974 required the Environmental Protection Agency (EPA) to devise national drinking water standards, which are primarily enforced by state governments authorized by the EPA. Part C of the act required the EPA to establish underground injection control programs "to prevent underground injection which endangers drinking water sources." At the time, the EPA interpreted the act to exclude fracking from underground injection regulation, arguing that the purpose of fracking is to extract natural gas and not to inject fluids into a well.[28][29]

The Energy Policy Act of 2005 modified federal law to exclude "the underground injection of fluids or propping agents (other than diesel fuels) pursuant to hydraulic fracturing operations related to oil, gas, or geothermal production activities" from the EPA’s underground injection control program. The 2005 act effectively permitted state and local governments to regulate fracking as the process relates to underground drinking water sources, though state regulations must meet the minimum requirements outlined in applicable federal regulations. In addition, state regulations apply to fracking on federal lands, and holders of federal leases must follow federal and state regulations on fracking. [29]

In 2015, the U.S. Bureau of Land Management (BLM) issued a regulation on fracking on federal lands, specifically regarding the regulation of wellbore construction, chemical disclosure, and water management, all of which fall under existing federal and state regulations. Two industry groups, the Independent Petroleum Association of America and the Western Energy Alliance, filed a suit challenging the regulation; the Sierra Club, an environmental group, filed a brief supporting the BLM. As of May 18, 2015, four states joined the suit against the BLM: Colorado, North Dakota, Utah, and Wyoming. On September 30, 2015, Judge Scott W. Skavdahl of the U.S. District Court for Wyoming blocked the rule from going into effect. Skavdahl wrote, "The fracking rule creates an overlapping federal regime, in the absence of congressional authority to do so, which interferes with the states’ sovereign interests in, and public policies related to, regulation of hydraulic fracturing." In June 2016, the court struck down regulation on its merits, arguing that the Energy Policy Act of 2005 and the Safe Drinking Water Act prevents the BLM from regulating fracking. According to the court's opinion, "The issue before this Court is not whether hydraulic fracturing is good or bad for the environment or the citizens of the United States." Instead, the court limited itself to examining whether applicable federal statutes show that Congress had delegated authority to the U.S. Department of the Interior (and by extension to the BLM) to regulate fracking, which the court ruled that Congress had not. In addition to the above four states, Alaska, Kansas, Montana, and Texas filed an amicus brief in the United States Court of Appeals for the 10th Circuit in opposition to the rule in September 2016.[30][31][32][33][34]

For more information on state-specific fracking regulations, click here.

Land

Oil spills on land can occur via pipeline leaks, railroad accidents, poor oil storage, natural seeping into land or soil, poor working practices, drilling accidents, and more. Inland oil spills can prevent water from being absorbed by the soil, and spills near agricultural operations or grassland can harm plant life and ecosystems. Cleaning up inland spills can depend on the kinds of soil affected, the geology of the area, the presence of groundwater sources, and how deep they are and access to the areas affected by the spill. Responses to these spills involve preventing the oil from contaminating groundwater sources or running off into surface waters like rivers and streams.[35]

Industry practices

Oil and natural gas producers adopt safety equipment and procedures aimed at preventing pollution and responding to spills or leaks. Equipment and procedures include the following:[36][37]

Equipment

  • Oil production facilities use blowout preventers, which are specialized valves or similar devices used to monitor and prevent the uncontrolled release of natural gas or crude oil from a well.[38]
  • Oil and natural gas pipelines have computers, electromagnetic devices, and ultrasonic instruments to detect potential vulnerabilities in pipeline equipment and alert employees who can conduct repairs in real time.[39]
  • Some oil tankers are double-hulled tankers. A double hull is a ship design in which the sides and bottom of a ship have an outer hull layer and an inner hull layer. Double-hulled tankers are used to decrease the likelihood of leaks or spills.[40]
Diagram of the types of directional wells
  • Above ground and underground storage tanks have leak prevention technology, such as oil and water separators and overfill sensors. An oil and water separator is used to recover oil spilled during the refining process. The device separates the oil from water and/or other solids and directs the oil out of the tank through a pipe via gravity or a pump. Meanwhile, the water is collected for removal through a separate pipe. Overfill sensors are found in the roof of a storage tank. They identify a specific level of petroleum production and trigger an automatic shut-off valve to prevent overfilling in a tank.[41][42]
  • Horizontal drilling (also known as directional drilling) is used to access oil and gas reserves that are not located directly underneath a drilling rig. Some oil and gas producers argue that directional drilling techniques allow operators to access oil and gas without disturbing nearby surface and subsurface lands.[43]

Procedures

  • Oil and gas producers adopt protocols and maintenance procedures to prevent spills and leaks. Spill, Prevent, Control, and Countermeasure Plans (SPCC) outline specific pollution prevention procedures. These documents and practices are shared between producers in the industry. The procedures require regular testing and inspection of pollution prevention equipment and processes.[44]
  • Oil and gas industry employees, such as equipment operators, are trained on prevention measures and emergency procedures. Tanker crews may use three-dimensional simulators in employee training. Instructors may control or revise these simulations to test employees on their responses to simulated real-time conditions.[45]
  • A catalog of standards covering employee training is shared across the oil and natural gas industry. In addition, oil and gas producers provide training courses as well as certification programs aimed at improving employee performance.[45]

Pollution over time

Industry proponents argued that air pollution levels have declined at the same time that oil and natural gas use has increased. These proponents cite data collected by the Environmental Protection Agency (EPA), which found that from 1980 to 2014, carbon monoxide levels fell by 69 percent, nitrogen oxide by 55 percent, particulate matter (PM10) by 58 percent, and sulfur dioxide by 81 percent. Industry proponents cited other data collected by the EPA, which found that from 1980 to 2015, the number of miles travelled by vehicles increased by 106 percent, energy consumption increased by 25 percent, and U.S. gross domestic product (GDP) increased by 153 percent. Some industry proponents credited private investment in more efficient vehicles and energy-using technologies and increased natural gas use caused by hydraulic fracturing (also known as fracking).[46][47][48]

Proponents of increased regulation argued that continued oil and gas use will continue to produce pollution such as particulate matter and smog. Opponents of increased natural gas use argued that pollution is produced at gas well sites. The Sierra Club, an opponent of natural gas production and use, argued that Sublette County, Wyoming, which the group claimed contained 27,000 gas wells, has higher smog levels than Los Angeles, California, and Houston, Texas. Some proponents of increased regulation argued that existing federal and state regulations are inadequate to limit air pollution from natural gas production. Further, these proponents argued that federal and/or state approval of increased oil production, including approval of oil-carrying pipelines such as Keystone XL and the Dakota Access pipeline, would increase air pollution by encouraging more oil use.[49][50][51]

Recent news

The link below is to the most recent stories in a Google news search for the terms Oil Natural Gas Pollution United States. These results are automatically generated from Google. Ballotpedia does not curate or endorse these articles.

Oil and natural gas pollution - Google News

Energy in the 50 states

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See also


Footnotes

  1. ↑ Live Science, "Pollution Facts & Types of Pollution," March 10, 2015
  2. ↑ Merriam Webster, "toxic," accessed August 13, 2015
  3. ↑ New York Department of Health, "What You Know Can Help You - An Introduction to Toxic Substances," accessed August 13, 2015
  4. ↑ Scientific American, "Strange but True: Drinking Too Much Water Can Kill," June 21, 2007
  5. ↑ National Oceanic and Atmospheric Administration, "Greenhouse gas benchmark reached," May 6, 2015
  6. ↑ The University of Waikato, "Measuring toxicity," accessed August 13, 2015
  7. ↑ National Oceanic and Atmospheric Administration, "Toxic Levels of Concern," accessed August 13, 2015
  8. ↑ U.S. Environmental Protection Agency, "Oil," September 25, 2013
  9. ↑ U.S. Environmental Protection Agency, "Natural Gas," accessed July 22, 2015
  10. ↑ U.S. Environmental Protection Agency, "Emissions from the Oil & Natural Gas Industry," July 1, 2015
  11. ↑ Earthworks, "Air Contaminates," accessed August 13, 2015
  12. ↑ Earthworks Action, "Sources of Oil and Gas Air Pollution," accessed July 22, 2015
  13. ↑ The terms wastewater, produced water, and flowback are sometimes used interchangeably, though all three refer to different types of water. The contaminated water that is stored in injection wells is called wastewater, which includes both produced water and flowback. Produced water is the salt water that has been under the earth for millions of years and is released when extracting oil or natural gas. Flowback is the fluid that was used when extracting oil or natural gas. This fluid returns to the earth's surface along with the oil or natural gas that is extracted. According to Energy in Depth, most of the wastewater that is produced during the fracking process is produced water.
  14. ↑ Energy in Depth, "Underground Wastewater Disposal," accessed July 9, 2015
  15. ↑ U.S. Environmental Protection Agency, "Air Quality Trends (1980-2013)," accessed July 24, 2015
  16. ↑ National Oceanic Atmospheric Administration, "Exxon Valdez Oil Spill," accessed July 24, 2015
  17. ↑ National Oceanic Atmospheric Administration, "Deepwater Horizon Oil Spill," accessed July 24, 2015
  18. ↑ 18.0 18.1 Society of Petroleum Engineers, "Hydraulic Fracturing 101: What Every Representative, Environmentalist, Regulator, Reporter, Investor, University Researcher, Neighbor and Engineer Should Know About Estimating Frac Risk and Improving Frac Performance in Unconventional Oil and Gas Wells," February 2012
  19. ↑ Union of Concern Scientists, "Environmental Impacts of Natural Gas," accessed July 23, 2015
  20. ↑ 20.0 20.1 The Hill, "EPA reverses course on fracking safety," December 13, 2016
  21. ↑ 21.0 21.1 21.2 U.S. Environmental Protection Agency, "Hydraulic Fracturing for Oil and Gas: Impacts from the Hydraulic Fracturing Water Cycle on Drinking Water Resources in the United States (Final Report)," accessed December 13, 2016
  22. ↑ 22.0 22.1 U.S. Environmental Protection Agency, "EPA Releases Final Report on Impacts from Hydraulic Fracturing Activities on Drinking Water," December 13, 2016
  23. ↑ Note: This text is quoted verbatim from the original source. Any inconsistencies are attributable to the original source.
  24. ↑ PR News Wire, "API: EPA distorts science in hydraulic fracturing study," December 13, 2016
  25. ↑ Energy in Depth, "*UPDATE* EPA Finalized Groundwater Report Reinforces No Widespread, Systemic Impacts from Fracking," December 13, 2016
  26. ↑ Common Dreams, " Statement of Wenonah Hauter, Executive Director, Food & Water Watch," December 13, 2016
  27. ↑ Sierra Club, "EPA report confirms threat posed by fracking," December 13, 2016
  28. ↑ [https://www.law.cornell.edu/uscode/text/42/300h Legal Information Institute, "42 U.S. Code § 300h - Regulations for State programs," accessed February 10, 2017
  29. ↑ 29.0 29.1 Congressional Research Service, "Hydraulic Fracturing and Safe Drinking Water Act Regulatory Issues," July 13, 2015
  30. ↑ Politico, "Interior's new fracking rules get swift GOP backlash," March 19, 2015
  31. ↑ Desert News, "Utah joins lawsuit over federal fracking rule," May 18, 2015
  32. ↑ The New York Times, "Judge Blocks Obama Administration Rules on Fracking," September 30, 2015
  33. ↑ Houston Chronicle, "Federal judge strikes down Obama's hydraulic fracturing rule," June 22, 2016
  34. ↑ Law 360, "States, Industry Urge 10th Circ. To Uphold Frack Rule Ban," September 23, 2016
  35. ↑ Oil Spill Prevention, "Land Spills," accessed July 24, 2015
  36. ↑ American Petroleum Institute, "Environmental Principles," accessed February 7, 2017
  37. ↑ Oil Spill Prevention and Response, "Refineries and Storage," accessed February 7, 2017
  38. ↑ Schlumberger, "Blowout preventer," accessed February 7, 2017
  39. ↑ Oil Spill Prevention + Response, "Equipment," accessed February 7, 2017
  40. ↑ Marine Insight, "Single Hull Vs Double Hull Tankers," accessed February 7, 2017
  41. ↑ Containment Solutions, "Underground Oil/Water Separators," accessed February 7, 2017
  42. ↑ Varec, "Overfill Prevention," accessed February 7, 2017
  43. ↑ NaturalGas.org, “Directional and Horizontal Drilling,” accessed January 28, 2014
  44. ↑ Oil Spill Prevention and Response," accessed February 7, 2017
  45. ↑ 45.0 45.1 Oil Spill Prevention and Response," accessed February 7, 2017
  46. ↑ Environmental Protection Agency, "Air Quality - National Summary," accessed February 10, 2017
  47. ↑ American Enterprise Institute, "What Americans ‘Know’ about Air Pollution Is False," June 1, 2006
  48. ↑ Western Energy Alliance, "Clearing the Air: Natural Gas Improves Our Air Quality," accessed February 10, 2017
  49. ↑ Sierra Club, "Dirty Fuels," accessed February 10, 2017
  50. ↑ Sierra Club, "Dirty, Dangerous, and Run Amok," accessed February 10, 2017
  51. ↑ Sierra Club, "Why move beyond natural gas?" accessed February 10, 2017
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