What Are Class II Wells
Class II injection wells are used to dispose of liquid waste from oil and gas production. This waste, often called “brine,” comes up from fracked wells carrying a toxic mix of chemicals, heavy metals, and radioactive elements. These wells are drilled about 5,500 feet deep, and the waste is forced underground at pressures above 1,000 psi into layers of porous rock known as pore space.
There is no underground pool or cavern where the waste collects. Instead, it spreads out horizontally through the rock, where it can migrate along cracks or faults.
The brine often contains hundreds of different chemicals used in the fracking process, including surfactants, lubricants, PFAS compounds, volatile organic compounds, and radioactive isotopes like radium-226 and radium-228.The radiation levels found in this wastewater brine can average as high as 9,330 pCi/L .The highest level of combined radium 226 and 228 found in Marcellus wastewater in a PA state study was 28,500 pc/L. The safe drinking water limit is 5 pc/L.
How Big the Problem Is
Across Ohio, there are over 230 Class II injection wells, and the amount of waste injected is staggering.
Between 2015 and 2024, 362,334,052 barrels of waste — equal to 15.2 billion gallons — were injected underground in Ohio. That’s the same as 23,057 Olympic-sized swimming pools of toxic waste.
Between 2010 (when the horizontal drilling “boom” started) and 2024, 18,385,326,624 gallons (over 18 billion!) or 27,856 Olympic Swimming Pools equivalent of toxic waste have been injected under Ohio’s ground!
Ohio’s Division of Oil and Gas Resources Management (ODNR) does not track this waste from cradle to grave. Once it leaves the well pad, there is no full accounting of where it goes or how it’s handled. The chemicals in this waste are legally classified as “non-hazardous” because of federal loopholes in the 1980 Resource Conservation and Recovery Act, meaning there is no public right to know what’s being injected.
Washington County: A Hotspot
Washington County is one of the hardest-hit areas in the state. It has 17 active Class II wells and 2 more recently permitted. If those are drilled, there will be 6 Class II wells within two miles of Marietta’s drinking water aquifer.
Washington County took in one-fifth of all brine waste injected in Ohio in 2023–2024. Over the last 15 years, the county alone has absorbed over 2,846,604,978 gallons (2.8 billion) gallons of waste,or 4,313 Olympic swimming pools.
The county has also experienced increased seismic activity in recent years. There are multiple fault lines beneath it, yet ODNR has not adequately investigated whether injection pressure and fluid migration are connected to these quakes.
Ohio: The Injection Well Hub of the Appalachian Basin
Ohio stands out in the region for the sheer number of Class II disposal wells, which are primarily used for disposing of toxic wastewater (brine) from oil and gas production, including waste imported from neighboring states.
| State | Approximate Number of Active Class II Disposal Wells | Ratio to Ohio’s Wells |
| Ohio | 241 | |
| West Virginia (WV) | 27 | Ohio has ~3.5x to 8x the number of wells as WV. |
| Pennsylvania (PA) | 18 | Ohio has ~15x the number of wells as PA. |