Definitions used with the Subsurface Wastewater Discharge and UIC Programs
There are many terms used in the Subsurface Wastewater Discharge and UIC Programs that are unique to those programs. As an aide to this web site, we're presenting a list of terms used to describe subsurface wastewater discharge. For the legal definitions of these terms, please consult:
- 38 M.R.S.A. §361-A, Definitions.
- 06-096, CMR, Chapter 543, Rules to Control Subsurface Discharge of Pollutants By Well Injection
- 40 CFR Part 144.3, Definitions (federal)
Agricultural drainage well - A type of Class V well used to drain farmland for cultivation or collect irrigation and stormwater runoff.
Aquifer - A geologic formation, group of formations, or part of a formation that is capable of yielding a significant amount of water to a well or spring.
Aquifer recharge well - A type of Class V well used to re-supply dwindling ground water resources.
Aquifer storage and recovery well - A type of Class V well used to place excess water in the subsurface during periods of high flow and then withdraw the water later when it is needed.
Authorized by rule - An owner or operator of an injection well who submits proper registration information to the UIC regulatory authority (the DEP, in Maine) may construct or use his or her well as long as the injection activity does not endanger ground water.
Beneficial use well - A type of Class V well that receives fluid to improve either flow of aquifers or have some other groundwater management benefit. Beneficial use wells include aquifer recharge wells and aquifer storage and recovery wells.
BOD - Biochemical oxygen demand. The quantify of oxygen utilized by a mixed population of microorganism in the aerobic oxidation of the organic matter in a sample of wastewater at a temperature of 20 degrees Celsius.
CERCLA - The Comprehensive Environmental Response, Compensation, and Liability Act of 1980, 42 U.S.C. 9601-9675. CERCLA is the law that was passed by Congress on December 11, 1980 to form what is commonly known as Superfund. CERCLA created a tax on the chemical and petroleum industries and required that the money collected be used to clean up hazardous waste sites throughout the country.
Cesspool - A drywell that receives untreated domestic wastewater containing human excreta and which sometimes has an open bottom and/or perforated sides.
Discharge - Any spilling, leaking, pumping, injecting, pouring, emptying, dumping, disposing or other addition of any pollutant to water of the State.
Domestic wastewater - Any wastewater produced by ordinary living uses, including liquid waste containing animal or vegetable matter in suspension or solution, or the water-carried waste from the discharge of water closets, laundry tubs, washing machines, sinks, dishwashers, or other source of water-carried wastes of human origin. This definition includes wastewater from commercial, industrial or residential sources which is of a similar quality (constituents and strength) to that produced by these same ordinary living uses.
Drywell - A well, other than a subsurface fluid distribution system, completed above the water table so that its bottom and side are typically dry except when receiving fluids.
Fluid - Any material or substance which flows or moves whether in a semisolid, liquid, sludge, gas, or any other form or state.
Fluid return well - A type of Class V well that receives discharges of water that has been used for heating or cooling a heat pump.
Formation - A body of consolidated or unconsolidated rock with similar lithologic characteristics which is prevailingly, but not necessarily, laterally continuous and is mappable on the earth's surface or traceable in the subsurface.
Ground water - All the waters found beneath the surface of the earth which are contained within or under this State or any portion thereof, except such waters as are confined and retained completely upon the property of one person and do not drain into or connect with any other waters of the State.
Holding tank - A closed, watertight structure designed and used to receive and store wastewater. A holding tank does not discharge wastewater to surface or ground water or onto the surface of the ground. Holding tanks are designed and constructed to facilitate ultimate disposal of wastewater at another site.
Home occupation food processing - The performance of food processing work at a single- or multi-family residence where the use of the property for food processing is secondary to the use of the property as a residence and at least one occupant of the residence is involved with the food processing work.
Industrial waste disposal well - Also known as an industrial well. A type of Class V well that receives discharges of non-domestic waste water.
Large-capacity cesspools - A type of Class V well that receives solely domestic wastewater and has the capacity to serve 20 or more person per day or dispose of 2,000 gallons or more of domestic wastewater per day. This term does not apply to single-family, other residential or non-residential cesspools below the capacity or flow limits specified.
Large-capacity septic systems - A type of Class V well that, with septic tank and disposal field, receives solely domestic wastewater and has the capacity to serve 20 or more person per day or dispose of 2,000 gallons or more of domestic wastewater per day. This term does not apply to single-family, other residential or non-residential septic systems below the capacity or flow limits specified above.
Mining and recovery well - A type of Class V well that receives discharges of fluids used in the production of energy or minerals; or for subsidence prevention, disposing of wastes and fire control in mining operations.
Motor vehicle waste disposal well - A type of Class V well that receives fluids discharged from areas in which vehicular repair or maintenance activities occur, including, but not limited to, activities performed at such businesses as automotive and auto body repair shops; new and used car and truck dealerships; aircraft, outboard engine, snowmobile, lawnmower, and ATV sales and repair shops; specialty repair shops; and any person that does gasoline- or diesel-engine repair work, whether those services are offered to the public or are solely for the person's own vehicle or fleet.
Non-domestic wastewater - Wastewater from commercial, industrial or residential sources which has constituents unlike that of or of significantly higher strength than that of domestic wastewater.
Non-endangerment - No owner or operator shall construct, operate, maintain, convert, plug, abandon, or conduct any other injection activity in a manner that allows the movement of fluid containing any contaminant into ground water, if the presence of that contaminant may cause a violation of any primary drinking water standard or may adversely affect the health of persons.
RCRA - The Resource Conservation and Recovery Act, 42 U.S.C. 6901-6992k. RCRA is the law that regulates the identification, transportation, treatment, storage, and disposal of solid and hazardous wastes in the United States.
Saline intrusion barrier well - A type of Class V well that is used to inject water into an aquifer to prevent intrusion of salt water into that aquifer.
SDWA - The Safe Drinking Water Act (Pub. L. 93-523, as amended; 42 U.S.C. 300f et seq.) The SDWA is the main federal law that ensures the quality of Americans' drinking water. Under SDWA, U.S. EPA sets standards for drinking water quality and oversees the states, localities, and water suppliers who implement those standards.
Septic system - A well that is used to discharge domestic wastewater below the surface and is typically comprised of a septic tank and disposal field.
Storm water drainage well - A type of Class V well used to remove storm water and urban runoff from surfaces such as roadways, roofs, and paved surfaces to prevent flooding.
Subsidence control well - A type of Class V well used to control land sinking, or subsidence, cause by ground water withdrawal.
Subsurface fluid distribution system - Also known as a disposal field. An assemblage of perforated pipes, drain tiles, or other similar mechanisms intended to distribute fluids below the surface of the ground.
TSS - Total suspended solids. The total of all settleable and nonsettleable solids in a sample of wastewater, measured in milligrams per liter by weight.
Waters of the State - Any and all surface and subsurface waters that are contained within, flow through, or under or border upon this State or any portion of the State, including the marginal and high seas, except such waters as are confined and retained completely upon the property of one person and do not drain into or connect with any other waters of the State, but not excluding waters susceptible to use in interstate or foreign commerce, or whose use, degradation or destruction would affect interstate or foreign commerce.
Well - Also known as injection well. A bored, drilled or driven shaft whose depth is greater than the largest surface dimension, whether the shaft is typically dry or contains liquid; or a dug hole whose depth is greater than the largest surface dimension; or a subsurface fluid distribution system.
Well injection - The subsurface discharge of fluids into or through a well.