From Beachapedia

What is Fracking?

Have you ever been frustrated trying to drink a thick milkshake or smoothie through a straw and blown into the straw to clear a path to improve the flow? In effect, you just “fracked” your drink. The industrial application of this technique is a little more complicated and controversial.

The oil and gas industry uses hydraulic fracturing or “fracking” to enhance subsurface fracture systems and increase the production of oil or gas from “tight” (fine-grained) geologic formations such as shale. Technically, fracking is just one of several "Well Stimulation Treatments" (WSTs) designed to enhance oil and gas production or recovery by increasing the permeability of the formation. WSTs include, but are not limited to, hydraulic fracturing treatments and acid well stimulations.

Fracking fluids, commonly made up of water, “proppants” (sand or ceramic beads) and various chemical additives, are pumped into a geologic formation at high pressure (up to 15,000 psi). The fracking process occurs after a well has been drilled and steel pipe (casing) has been inserted in the well bore. The casing is perforated (has holes or slots) within the target zones that contain oil or gas, so that when the fracturing fluid is injected into the well it flows through the perforations into the target zones. Eventually, the target formation will not be able to absorb the fluid as quickly as it is being injected. At this point, the pressure created causes the formation to crack or fracture. Once the fractures have been created, injection ceases and a portion of the fracturing fluids begin to flow back to the surface. Proppants, which were injected as part of the frac fluid mixture, remain in the target formation to hold open the fractures.

Some studies have shown that anywhere from 20-85% of fracking fluids may remain underground. Used fracturing fluids that return to the surface (called flowback) are typically stored in open pits or tanks at the well site prior to re-use or disposal.

Hydraulic Fracturing (Granberg/ProPublica)

Environmental Concerns

The process of hydraulic fracturing a well raises several potentially significant environmental concerns, including high water use, the use of toxic chemicals, contamination of soil, surface water and groundwater, human heath concerns, air quality impacts, and hazardous waste disposal issues. When fracking is done offshore, there are additional concerns related to potential impacts to marine life. Congress has asked the US EPA to conduct a major research effort to gather data to evaluate these concerns. The following sections provide an overview of some of the issues and impacts related to this well stimulation technique.

Water Use

In 2010, the U.S. Environmental Protection Agency estimated that 70 to 140 billion gallons of water are used to fracture 35,000 wells in the United States each year. This is approximately the annual water consumption of 40 to 80 cities each with a population of 50,000. Fracture treatments in deep horizontal shale wells can use anywhere from 2 to 10 million gallons of water to fracture a single well. The use of so much water for fracking has raised concerns about the ecological impacts to aquatic resources, as well as dewatering of drinking water aquifers. The amount of water used to "frack" a well can vary greatly, depending on the depth of the well, the geology, and whether the well is an oil or natural gas well. Wells that have been fracked in California reportedly use a little more than 100,000 gallons of water, while fracking in other areas of the country may use millions of gallons of water. An article published in February 2014 referenced a study that indicated of the nearly 40,000 oil and gas wells drilled since 2011, three-quarters were located in areas where water is scarce, and 55% were in areas experiencing drought. One interesting response to addressing the issue of water use in fracking operations is a plan to utilize treated wastewater for fracking in Mississippi rather than potable water.

Toxic Chemicals

In addition to large volumes of water, a variety of chemicals or additives are used in hydraulic fracturing fluids. These chemicals may include acids, biocides, corrosion inhibitors, viscosity adjusters, gelling agents, solvents and surfactants.

Many fracturing fluid chemicals are known to be toxic to humans and wildlife, and several are known to cause cancer. Potentially toxic substances include petroleum distillates such as kerosene and diesel fuel; polycyclic aromatic hydrocarbons; volatile organic compounds (VOCs) such as benzene and 1,2-dichloroethane; methanol; formaldehyde; ethylene glycol; glycol ethers; hydrochloric acid; and sodium hydroxide.

VOCs not only pose a health concern while in the water, the volatile nature of the constituents means that they can also easily enter the air. Organic compounds brought to the surface in the fracturing flowback or produced water often go into open impoundments (frac ponds), where the VOCs can offgas into the air.

Human exposure to fracking chemicals can occur by ingesting chemicals that have spilled and entered drinking water sources, through direct skin contact with the chemicals or wastes (e.g., by workers, spill responders or health care professionals), or by breathing in vapors from flowback wastes stored in pits or tanks.

A congressional report sampling incomplete industry self-reports found that “[t]he oil and gas service companies used hydraulic fracturing products containing 29 chemicals that are (1) known or possible human carcinogens, (2) regulated under the Safe Drinking Water Act for their risks to human health, or (3) listed as hazardous air pollutants under the Clean Air Act.”[1] One peer-reviewed scientific study reviewed a list of 944 fracking fluid products containing 632 chemicals, 353 of which could be identified with Chemical Abstract Service numbers.[2] The study concluded that more than 75 percent of the chemicals could affect the skin, eyes, and other sensory organs, and the respiratory and gastrointestinal systems; approximately 40 to 50 percent could affect the brain/nervous system, immune, and cardiovascular systems, and the kidneys; 37 percent could affect the endocrine system; and 25 percent could cause cancer and mutations.[3] Another study reviewed exposures to fracking chemicals from onshore wells and noted that trimethylbenzenes are among the largest contributors to non-cancer threats for people living within a half mile of a well, while benzene is the largest contributor to cumulative cancer risk for people, regardless of the distance from the wells.[4]

Surface Water and Soil Contamination

Spills of fracturing chemicals and wastes during transportation, fracturing operations and waste disposal have contaminated soil and surface waters in several locations in Pennsylvania, Colorado and other areas where intensive fracking operations have occurred.

Groundwater Contamination

In 2004, the U.S. Environmental Protection Agency (EPA) released a final study on Evaluation of Impacts to Underground Sources of Drinking Water by Hydraulic Fracturing of Coalbed Methane Reservoirs. In the study, EPA found that ten out of eleven coalbed methane basins in the U.S. are located, at least in part, within underground sources of drinking water (USDWs). Furthermore, the EPA determined that in some cases, hydraulic fracturing chemicals are injected directly into USDWs during the course of normal fracturing operations. Calculations performed by EPA in the draft version of its study show that at least nine hydraulic fracturing chemicals may be injected into or close to USDWs at concentrations that could pose a threat to human health. EPA’s study indicates that chemicals may be injected at concentrations that are anywhere from 4 to almost 13,000 times the acceptable concentration in drinking water.

The potential long-term consequences of dewatering and hydraulic fracturing on water resources have been summed up by professional hydrogeologist who spent 32 years with the U.S. Geological Survey:

“At greatest risk of contamination are the coalbed aquifers currently used as sources of drinking water. For example, in the Powder River Basin (PRB) the coalbeds are the best aquifers. CBM production in the PRB will destroy most of these water wells; BLM predicts drawdowns...that will render the water wells in the coal unusable because the water levels will drop 600 to 800 feet. The CBM production in the PRB is predicted to be largely over by the year 2020. By the year 2060 water levels in the coalbeds are predicted to have recovered to within 95% of their current levels; the coalbeds will again become useful aquifers. However, contamination associated with hydrofracturing in the basin could threaten the usefulness of the aquifers for future use.”

Another recent study has also found increased arsenic and heavy metals in groundwater near fracking sites in Texas.[5]

Defenders of fracking often make claims that fracking has been used for decades on over a million wells without a proven case of groundwater contamination caused by fracking. A blog post by John Amos on his Skytruth website analyses these claims and reveals that careful choices of words and their definitions are perhaps being used to obscure the truth. He concludes:

"The track record of modern fracking is shrouded in incomplete information, a misleading history, and distorted by semantic arguments that narrowly define what counts as contamination from fracking. While cases of contamination caused by fracking remain obscured by lack of information and tricky linguistics, we know that a growing number of citizens are reporting harm and environmental contamination in unconventional oil and gas fields, and especially from wells that have been fracked."[6]

Also see Frac Facts from the Wilderness Society.[7]

Waste Disposal

As mentioned above, a large portion of the hydraulic fracturing fluids return to the surface as “flowback.”. This means that for some shale gas wells, millions of gallons of wastewater are generated, and require either treatment for re-use, or disposal.

In 2009, the volume of fracturing flowback and brines produced in Pennsylvania was estimated to be 9 million gallons of wastewater per day, and this figure was expected to increase to 19 - 20 million gallons/day in 2011. The sheer volume of wastes, combined with high concentrations of certain chemicals in the flowback from fracturing operations, are posing major waste management challenges.

Radioactive materials in wastewater from natural gas wells are also a concern. Options for disposal of radioactive flowback or produced water include underground injection in Class II UIC wells and offsite treatment.

During the fall of 2008, the disposal of large volumes of flowback and produced water at publicly owned treatment works (POTWs) contributed to high total dissolved solids (TDS) levels measured in Pennsylvania’s Monongahela River and its tributaries. Studies showed that in addition to the Monongahela River, many of the other rivers and streams in Pennsylvania had a very limited ability to assimilate additional TDS, sulfate and chlorides, and that the high concentrations of these constituents were harming aquatic communities.

Disposal of drilling and fracking wastewater is likely to continue to present a challenge to local and state governments as more wells are developed across the country.

Hydraulic Fracturing Best Practices

From a public health perspective, if hydraulic fracturing stimulation takes place, the best option is to fracture formations using sand and water without any additives, or sand and water with non-toxic additives. Non-toxic additives are reportedly being used by the offshore oil and gas industry, which has had to develop fracturing fluids that are non-toxic to marine organisms. It should be noted that this claim is difficult to verify given the reluctance of oil and gas companies to disclose the chemicals they use for fracking.

Oil and gas wastes are often flowed back to and stored in pits on the surface. Often these pits are unlined. But even if they are lined, the liners can tear and contaminate soil and possibly groundwater with toxic chemicals. Therefore, storage in aboveground tanks is recommended.

What About Fracking for Offshore Wells?

In addition to onshore applications, fracking can also be conducted to increase oil and gas production in offshore wells. An example of this occurred in 2009 on Platform Gail in the Sockeye field in federally controlled waters near Santa Cruz Island off the coast of southern California. As reported on the Environmental Defense Center website:

“In June 2011, EDC research uncovered that Venoco, Inc., had fracked from an offshore oil platform located in Federal waters in late 2009. Staff with the Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE), since divided into two separate agencies) confirmed that Venoco conducted its frack job from Platform Gail, located off of the Ventura County coast. According to BOEMRE, Venoco's fracking operation was allowed under existing authorizations, and no further environmental analysis or public disclosure was made prior to the operation, despite the fact that offshore oil development raises its own host of environmental issues.”

Venoco may also be planning or may have already used fracking to enhance oil production at their other active offshore oilfield in California state waters, known as South Ellwood.

The fracking that is occurring or may occur on at least one of Venoco's offshore oilfields has the potential for the leakage of fracking fluids from either the oil wells or from any injection wells where produced water or fracking wastewater may be disposed. When there is leakage of a natural gas well, oil well or a wastewater injection site onshore, it often can be detected in the water table or even on the surface of the ground. On offshore sites, leakage could go on for long periods of time without detection and be widely dispersed by tides and currents. The Sockeye oil field is nearby to Channel Island Marine Protected Areas and a spill or long-term leak could do major injury to the ecosystem. The South Ellwood oil field is close to the coast and could contaminate the Santa Barbara beaches for some time without detection. The area near the Ellwood fields is known for having large natural fractures in the ocean floor. Any fracking fluids injected into wells offshore could travel through natural fractures already in the rocks into the ocean waters.

State and Federal Regulations

The state agency responsible for overseeing fracking [Division of Oil, Gas and Geothermal Resources (DOGGR)] received funds in its 2010-2011 budget to issue regulations on fracking, but has been slow to issue the regulations. Moreover, in January 2011, Elena Miller, the head of the division at the time, told EWG that it had no plans to do so. A year later, in February 2012, Mark Nechodom, newly appointed director of the Department of Conservation, told EWG and six other environmental organizations following repeated questioning that the agency does not have fracking regulations "on its plate." He said the department would only begin to develop such regulations if the legislature were to require them or there was "manifest damage and harm" from fracking in California.

The California state legislature has tried to pass laws on fracking, but the bills were defeated. An example is SB 1054, a seemingly simple measure proposed by state Senator Fran Pavley that would have required energy firms to notify property owners before using hydraulic fracturing to increase oil production near their land. This bill was rejected in March 2012. Senator Pavley introduced another bill, SB 4, which was finally approved in September 2013 after much negotiation and modifications.

DOGGR, now under intense pressure from state environmental groups, is finally starting to study what regulations they may require, but it could take several months or longer for the state legislature to pass any fracking laws. An update from October 2012 on state efforts to regulate fracking can be found here.

In December 2012 DOGGR released draft Hydraulic Fracturing Regulations for “discussion.” A formal public comment period was expected to begin in 2013.

Effective January 1, 2014, the Department of Conservation established interim regulations to govern oil and gas well stimulation treatment until the permanent regulations are completed and become effective. The Department is ensuring that these interim regulations continue until January 1, 2015. More information about the interim regulations -- including the text of the readopted interim regulations -- can be found here. In June 2014 the California Department of Conservation issued Revised Proposed Regulations for "Well Stimulation" (hydraulic fracturing and other treatments that increase the flow of oil and natural gas to wells and then to the surface for recovery). The text of the revised proposed regulations can be found here.

On December 30, 2014, the Office of Administrative Law (OAL) approved and filed the final proposed regulations on well stimulation treatments with the Office of the Secretary of State. Documents associated with the rulemaking process, including the final text of the regulations, OAL's approval letter, and the Final Statement of Reasons, can be found here. More background information about the regulations can be found here.

In January 2014 the U.S. Environmental Protection Agency (EPA) stepped into the act by establishing a new requirement for oil and gas operations off the Southern California coast to publicly report chemicals dumped directly into the ocean from offshore fracking operations. The notice, published January 9, announces the changes as part of a new permit for water pollution discharges from offshore oil and gas operations in federal waters off California. The reporting requirement will become effective March 1. The EPA revised the offshore oil and gas wastewater discharge permit to require reporting of the chemicals of any fracking fluids discharged into the ocean. In response to the controversy generated by recent reports of fracking of oil and gas wells along the California coast, the EPA revised the offshore oil and gas discharge permit to require reporting of the chemical formulations of any fracking fluids discharged by oil companies. Approximately half the oil platforms in federal waters in the Santa Barbara Channel discharge all or a portion of their wastewater directly to the ocean, according to a California Coastal Commission document. This produced wastewater contains all of the chemicals injected originally into the fracked wells, with the addition of toxins gathered from the subsurface environment.

Regarding onshore facilities, in March 2015 US EPA announced that they were proposing pretreatment standards for the Oil and Gas Extraction Category (40 CFR Part 435). The regulations would address discharges of wastewater pollutants from onshore "unconventional oil and gas (UOG) extraction facilities" to publicly-owned treatment works (POTWs).

More Revelations on Offshore Fracking

As detailed in an August 13, 2013 letter to the California Coastal Commission from the Center for Biological Diversity, Environmental Defense Center and Surfrider Foundation, federal regulators within the U.S. Department of the Interior at the Bureau of Ocean Energy Management (“BOEM”) and Bureau of Safety and Environmental Enforcement (“BSEE”) have permitted fracking in federal waters on existing leases in the Pacific Ocean at least 12 times since the late 1990s, and have recently approved a new project.[8] Apparently neither BOEM nor BSEE sought a consistency review of applications for permits to drill using hydraulic fracturing, as required by 16 U.S.C. § 1456(c)(3)(A). Moreover, in June 2013, the California Coastal Commission approved a consistency determination for the general National Pollutant Discharge Elimination System (NPDES) permit CAG280000 for discharges from offshore oil and gas platforms located in federal waters off the coast of Southern California. The environmental groups are concerned that the Commission was unaware that companies are fracking off the California Coast at the time it approved this consistency determination, calling into question its legality, since fracking poses distinct and unstudied risks to water quality above and beyond that posed by conventional oil and gas development.

As discussed above, water contamination is a particular hazard with fracking because hundreds of toxic chemicals are used in fracking fluid. While the oil and gas industry has to date successfully resisted the full disclosure of fracking and other well stimulation chemicals, what is known is cause for extreme concern.[9] According to the Center for Biological Diversity, oil rig operators have federal permits to dump more than nine billion gallons of fracking wastewater into California's ocean waters each year.[10] Although these discharges are apparently legal, researchers at the Center for Biological Diversity believe that these discharges of toxic chemicals pose a danger to marine life.[11]

While the impacts to wildlife have received less study, these chemicals pose a threat to marine life. During fracking, a significant amount of the fracking fluid returns to the surface and is either discharged into the ocean or transported for onshore ground injection. At sea, these chemicals enter the marine ecosystem.

Research by the Center for Biological Diversity demonstrates that fracking is currently occurring in state waters as well. The August 13, 2013 letter included a compilation of a dozen records from the voluntary reporting site for wells that have been fracked in state waters in the past several years. Because contains only partial information on wells fracked since January 1, 2011, that have been voluntarily reported by operators, this compilation is virtually certain to be an underestimate of the actual number of frack jobs that have already occurred. In waters off Long Beach, Seal Beach and Huntington Beach—some of the region's most popular surfing strands and tourist attractions—oil companies have used fracking at least 203 times at six sites in the past two decades, according to interviews and drilling records obtained by The Associated Press through a public records request.[12]

To date the environmental groups writing the letter have been unable to locate any environmental review conducted pursuant to the California Environmental Quality Act (“CEQA”) or other authority for these fracking operations by the California State Lands Commission or other agencies. Some information is provided on the FracFocus record itself, and some additional information is available through an online well records search of the DOGGR website, but this information is insufficient to assess the dangers of offshore fracking in state waters.

As a result of the recent revelations regarding fracking in both state and federal waters off the coast of southern California, Surfrider Foundation is calling for a moratorium on offshore fracking until oil/gas companies and government officials conduct proper Environmental Impact Statements/Reports, provide independent scientific studies, and include a public process that is rooted in transparency (as required under both CEQA and NEPA).

UPDATES: In a settlement reached in late January 2016, the federal government agreed to stop approving offshore drilling permits in the state of California until an environmental review could be completed. This comes after suits were brought by two concerned groups, the Center for Biological Diversity and the Environmental Defense Center (EDC), who argued that by allowing the oil industry to dump over 9 billion gallons of wastewater off the coast of California every year, the state threatens marine life. More. The Bureau of Ocean Energy Management (BOEM) and the Bureau of Safety and Environmental Enforcement (BSEE) released a draft Environmental Assessment (EA) in February 2016. EDC criticized the EA as being inadequate, with five "fundamental failings." After receiving and evaluating comments letters from industry, government agencies, environmental organizations and the general public, including this letter from EDC and Surfrider Foundation, BOEM/BSEE released their final Environmental Assessment in May 2016. BOEM and BSEE concluded that there was a Finding of No Significant Impact. This conclusion angered many environmental groups, including the Center for Biological Diversity and Environmental Defense Center.

Offshore fracking is not just an issue in California. In 2016, an article in Climate Progress, citing information obtained by Center for Biological Diversity, revealed that:

Under the Obama administration, between 2010 and 2014, more than 1,200 permits to frack in the Gulf were approved through a largely rubber-stamp process, the Center for Biological Diversity said. The EPA, which does not permit offshore drilling, has meanwhile allowed fracking companies to dump their wastewater directly into the ocean, with little to no environmental review and no system of water monitoring.

You can read more about this issue, including Surfrider Foundation’s Position Statement on Offshore Fracking in California here.


  1. See, e.g.,United States House of Representatives, Committee on Energy and Commerce Minority Staff, Chemicals used in hydraulic fracturing, April 2011
  2. Dearen, Jason and Alice Chang, Offshore Fracking Off California Coast Under Review, Drawing Calls For Increased Regulation (Aug. 3, 2013)
  3. Dearen, Jason and Alice Chang, Offshore Fracking Off California Coast Under Review, Drawing Calls For Increased Regulation (Aug. 3, 2013)
  4. McKenzie, Lisa et al., Human Health Risk Assessment of Air Emissions form Development of Unconventional Natural Gas Resources, Sci Total Environ (2012), doi:10.1016/j.scitotenv.2012.02.018
  5. Fontenot, Brian E et al., An evaluation of water quality in private drinking water wells near natural gas extraction sites in the Barnett Shale Formation, Environmental Science & Technology (2013).
  6. Word Games are Misleading the American Public About Fracking,, November 8, 2013.
  7. Industry’s Misleading Statements about Hydraulic Fracturing (or Fracking) and How Best to Respond, By Lois Epstein, P.E., Engineer (July 2014)
  8. Dearen, Jason and Alice Chang, Offshore Fracking Off California Coast Under Review, Drawing Calls For Increased Regulation (Aug. 3, 2013)
  9. See, e.g.,United States House of Representatives, Committee on Energy and Commerce Minority Staff, Chemicals used in hydraulic fracturing, April 2011; see also Colborn, Theo et al., Natural Gas Operations for a Public Health Perspective, 17 Human and Ecological Risk Assessment 1039 (2011); McKenzie, Lisa et al., Human Health Risk Assessment of Air Emissions form Development of Unconventional Natural Gas Resources, Sci Total Environ (2012), doi:10.1016/j.scitotenv.2012.02.018.
  11. Jerome, Sara, What Is The Real Impact Of Fracking On The Ocean?, November 7, 2014
  12. Chang, Alicia and Dearen, Jason, Associated Press, Calif. finds more instances of offshore fracking (October 21, 2013)


Hydraulic Fracturing 101 (

Hydraulic Fracturing Background Information (USEPA)

Natural Gas Extraction - Hydraulic Fracturing (USEPA)

Lack of State and Federal Oversight of Offshore Fracking Could Imperil the Santa Barbara Coastline (

Special Investigation: Fracking in the Ocean Off the California Coast (

Offshore - Fracking in Federal Waters (Environmental Defense Center)

Hydraulic Fracturing in California (DOGGR)