Unconventional oil and gas development produces billions of tons of waste annually. Waste products from shale gas operations include:

  1. Liquid waste such as brine and flowback water
  2. Sludges and semi-solids like tank bottoms
  3. Concentrated TENORM (technologically-enhanced naturally occurring radioactive material)
  4. Filter cake, filter socks, and material residues
  5. Solid waste such as drill cuttings

Unconventional oil and gas development requires extraordinary quantities of water during the extraction process. In 2019, drilling operators used an average of 14 million gallons of water per fracking event. Some hydrofracturing jobs required up to 39 million gallons for a single well. After it is pumped underground to “frack” oil and gas wells, water that initially returns to the surface is called “flowback,” and includes naturally-occurring underground brine water– containing dangerous levels of radiation, heavy metals, and other contaminants — mixed with the fracking chemical-laden fresh water that has been pumped into the well. The chemicals used in the fracking process are known carcinogens, while others remain entirely secret (or “proprietary” by industry), even to the personnel in the field who are employed to use the additives.

Flowback is disposed of by injection into underground wells, in water treatment plants, or in open air pits. Each of these disposal methods comes with enormous risks, such as contamination of drinking water sources, fresh water contamination, inducing seismic activity in the case of underground injection, human exposure to radioactivity, and increased traffic needed to transport produced water.

Produced water, which flows out of the shale throughout the lifetime of the well, contains fewer of these chemicals used to frack the well, itself. Sometimes produced water is treated to remove remaining fracking chemicals and is then reused in the fracking process. However, because fresh water is less expensive to obtain — at least in non-arid parts of the country — this accounts for only a portion of the water used to stimulate a given well.

Shockingly, some states allow for fracking wastewater to be treated and used for agricultural purposes, for road spreading, or for commercial sale in products such as pool salts, increasing exposure pathways to toxic chemicals.

Scroll down to explore articles on FracTracker’s work as it relates to fracking waste issues.

Class II Injection Wells

There are over 150,000 injection wells in the U.S. A break down by state is available from the US EPA.

Class II underground injection wells are a major disposal pathway for liquid oil and gas exploration and production wastes. Much of the solid waste from oil and gas wells will end up in landfills or other types of impoundments, as well as spread on the surface (called land-spreading).

Class II Wastes Include:

  • Produced water
  • Drilling fluids
  • Spent well treatment or stimulation fluids
  • Pigging wastes
  • Gas plant wastes (including Amine and Cooling tower blowdown)

For disposal, the majority of the liquid is pressed from the solid waste and re-injected back into the ground into Class II injection wells. These liquids are a combination of drilling mud compounds, hydraulic fracturing chemicals, well cleansing acids, and formation fluids. These fluids can be high in naturally occurring radioactive materials (NORMs), hydrocarbons, heavy metals, and other toxics. Such a disposal process is regulated by the U.S. EPA’s underground injection control program, with primacy (authority) granted to states to regulate permitting (COGCC in Colorado, DOGGR in California, RRC in Texas, PADEP in Pennsylvania, Ohio EPA in Ohio, etc.).

This is all outlined in Resource Conservation and Recovery Act (RCRA) Subpart C on Exempt Waste. But because RCRA’s exempt status here is based on the relationship of the waste to exploration and production operations, and not on the chemical nature of the waste, it is possible for an exempt waste and a non-exempt hazardous waste to be chemically very similar. 

North Dakota Frack Waste Report

A 2020 report by Earthworks accompanied by an interactive map that allows residents to determine if oil and gas waste is disposed of or has spilled near them in addition to a list of recommendations for state and local policymakers, including the closing of the state’s harmful oil and gas hazardous waste loophole. Click the icon to access the report and map.

Pennsylvania Oil & Gas Waste: report and interactive map

With FracTracker Alliance and using PA DEP data, Earthworks created a map allowing users to search and see how much PA oil and gas waste is being processed, transported, and disposed near them each year since 2011. States as distant as Idaho are involved. Click the icon to access the report and map.

Pennsylvania is Discharging Radioactive Fracking Waste

Where and how this is all happening is best illustrated in the Public Herald interactive map “How Radioactive Fracking Waste Gets Into Pennsylvania Waterways” — produced with FracTracker Alliance. Click the icon to access the article and map.

FracTracker Waste Articles


Groundwater risks in Colorado due to Safe Drinking Water Act exemptions

Oil and gas operators are polluting groundwater in Colorado,…
Northeast Ohio Class II injection wells taken via FracTracker's mobile app, May 2015

What are aquifer exemptions? Permitted exemptions from the Safe Drinking Water Act

Liquid Waste Disposal Drilling for oil and gas produces both…
Brine or water roadspreading in WV

Does roadspreading of brine equate to oil and gas waste dumping?

The application of liquid oil and gas waste from conventional…
Ethanol and fracking

North American Ethanol’s Land, Water, Nutrient, and Waste Impact

Corn Ethanol and Fracking - Similarities Abound Even though…

Radium Watersheds a Risk

By Greg Pace - Columbus Community Bill of Rights, and Julie Weatherington-Rice…
For schools and hospitals analysis, 2017

How close are schools and hospitals to drilling activity in West Virginia and Ohio?

A review of WV and OH drilling activity and its proximity…

Data Downloads

OH Class II Wells - TAAD

Temporarily Abandoned Annular Disposal (TAAD) data for Class II wells in Ohio as of April 2016

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