Injection Wells
The Division protects Ohio's groundwater resources by regulating the disposal of brine and other wastes produced from the drilling, stimulation, and production of oil and natural gas in Ohio. The Division received primacy of its Underground Injection (UIC) Program from U.S. EPA in 1983.
Ohio's Class II disposal wells include conventional brine injection wells, annular disposal wells, and enhanced oil recovery injection wells. Enhanced recovery injection wells are used to increase the production of hydrocarbons from nearby producing wells.
Division UIC personnel review construction specifications, engineering, geological data, and issue permits for Class II wells used to inject fluids, primarily oil-field brine, into deep, underground geological formations for disposal or for secondary oil recovery. The Division also regulates the hauling and spreading of oil-field brine. Brine haulers in Ohio are required to be registered, bonded, and insured with the Division of Oil and Gas Resources Management.
Oil-field brine is a saline by-product generated during oil and gas well operations. The salinity, or dissolved content, of Ohio oil-field brines vary considerably from one geologic formation and can vary regionally within the same formation. Ohio brines can be more than six times as salty as seawater.
Approximately 98 percent of all brine is safely disposed of by injection back into brine-bearing or depleted oil and gas formations deep below the surface. Nearly two percent is spread for dust and ice control subject to local government approval and requirements.
Looking for Forms/Applications associated with the Underground Injection Control Program? Visit the Documents and Forms page.
Classifications
| CLASS | USE | NATIONAL INVENTORY |
|---|---|---|
| Class I | Inject hazardous wastes, industrial non-hazardous liquids, or municipal wastewater beneath the lowermost USDW* | 650 |
| Class II | Inject brines and other fluids associated with oil and gas production, and hydrocarbons for storage. | 151,000 |
| Class III | Inject fluids associated with solution mining of minerals beneath the lowermost USDW*. | 21,000 |
| Class IV | Inject hazardous or radioactive wastes into or above USDWs. These wells are banned unless authorized under a federal or state groundwater remediation project. |
24 |
| Class V | All injection wells not included in Classes I-IV. In general, Class V wells inject non-hazardous fluids into or above USDWs and are typically shallow, on-site disposal systems. However, there are some deep Class V wells that inject below USDWs. | 400,000-650,000 |
| Class VI | Inject Carbon Dioxide (CO2) for long term storage, also known as Geologic Sequestration of CO2. | 6-10 by 2016 |
*USDW – Underground Source of Drinking Water – an aquifer or its portion that supplies any public water system or contains sufficient quantity of groundwater to supply a public water system, or contains less than 10,000 milligrams per liter total dissolved solids and is not an exempted aquifer. Groundwater Protection Council, wwwgwpc.org
Definitions
Class II Saltwater Injection Wells
A well constructed and used for the sole purpose of disposing of saltwater, a byproduct of oil and natural gas production. A saltwater injection well is constructed to isolate the injected fluid in a specific formation and prevent contamination of freshwater.
Class II Enhanced Oil Recovery Wells
An enhanced oil recovery project is composed of both injection wells and withdrawal wells. The intent in an enhanced recovery project is to inject a substance into a producing formation in decline, thereby increasing oil and/or natural gas production in the surrounding withdrawal wells. In some cases, the substance injected is produced saltwater (brine). Enhanced recovery project injection wells are subject to the same permitting, construction, operation, and monitoring requirements as saltwater injection wells.
Class II Annular Disposal Wells
Annular disposal is a method of disposal in which a producing oil and gas well is also used to dispose of saltwater. The saltwater is injected between the surface casing and the production casing, as shown in the diagram. The protection of freshwater is from the surface casing only, which must be set fifty feet below the deepest freshwater bearing formation and sealed to the surface. Mechanical integrity of the casing is tested once every five years.
Class III Salt-Solution Mining Injection Wells
Class III salt-solution mining wells are used to produce saturated brine from the salt deposits that occur from 2000 to 3500 feet below Ohio's ground surface. The saturated brine is then used to make table salt, water softener salt, and salt blocks. All types of injection wells are designed to ensure safe injection into permitted formations.
In Ohio, solution mining involves the drilling of wells into the Salina salt deposits (that range from approximately 2000 to 3200 feet below the surface depending where you are in Northeast Ohio) and injecting freshwater or under-saturated brine into the salt deposits to dissolve the salt. As the salt is dissolved, an underground cavern is formed that is filled with fluid and pumped back to the surface as saturated brine. The brine is then either used as a raw material for chemical processing or for the manufacturing of table salt, water softener salt, or salt blocks for animals.
At least 300 wells at ten different facilities in Ohio have been drilled and operated since the late 1800s. Only three facilities and approximately 50 wells remain in operation today in Wayne, Medina, and Summit counties.
Prior to 1983, there were no regulations regarding solution-mining operations in Ohio. Today, the Division of Oil and Gas Resources Management requires annual subsidence surveying by each of the three operational solution-mining facilities. There is no documented evidence of sink-hole formation due to solution mining in Ohio. Sink-hole formation due to solution mining is well documented in Michigan, New York, Kansas, and Ontario, Canada where the salt beds are a lot shallower than in Ohio.
Brine Hauling and Spreading
The spreading of oil-field brine is a legal, cost-effective, and efficient way to control dust and ice problems on local roads and private property in Ohio. Ohio's UIC Program regulates the hauling and spreading of oil-field brine, while local authorities, such as the County Commissioners and Township Trustees, permit the actual spreading on public roads and private property.
The division reviews all local brine spreading resolutions and plans passed by the local jurisdictions to ensure compliance with state law. State law requires a minimum of nine brine spreading standards incorporated into all local resolutions. Local authorities have the power to require spreading standards that are more stringent than state law.
All registered brine haulers must have the identification number issued by the division, the word "BRINE", and the name and telephone number of the hauler on the sides or rear of their trucks. All of this information must be in reflective paint and the letters on the vehicle must be no less than four inches in height. Ohio oil-field brine haulers must maintain a daily log in their trucks.