In this chapter, the following terms have the meanings indicated. Terms Defined. “Abandonment” means to discontinue the use of a well permanently. “Annular space” means the space between casings or between the casing and borehole. “Approving Authority” means the Secretary of the Environment or the Secretary’s designee. “Aquifer” means a formation, group of formations, or part of a formation that contains sufficient saturated permeable material to yield significant quantities of water to a well. Bedrock. “Bedrock” means solid rock that underlies gravel, soil, or other superficial material. “Bedrock” also means in absolute terms material that a 6-inch auger, equipped with carbide cutting teeth, penetrates at a rate of less than 1 inch in 3 minutes. “Bentonite” means a colloidal clay, composed of at least 85 percent sodium montmorillonite. “Bored well” means any excavation made using power driven equipment where the drill consists of a continuous spiral of metal solid or hollow stem auger or bucket attached to a shaft and where the excavated material is brought to the ground surface by upward movement along the surface of the spiral or removed by lifting the spiral or bucket. “Borehole” means a hole drilled or bored into the earth, into which casing, screen, liners, grout, gravel pack and other physical objects that may be installed to construct a well. The generalized term includes the excavations for dug, driven, and jetted wells. “Casing” means any metal, plastic or other pipe installed from the surface to either the bedrock or screened aquifer in the borehole. “Cathodic protection well” means a well constructed to minimize the electrolytic corrosion of metallic equipment that comes in contact with the ground. “Cluster” means a group of wells that are constructed for the same use on the same property. “Confined aquifer” means an aquifer that is bounded above and below by beds of distinctly lower permeability than that of the aquifer itself and contains ground water under pressure greater than that of the atmosphere. This term is synonymous with the term “artesian aquifer”. “Confining layer” means a body of impermeable or of distinctly less permeable material stratigraphically adjacent to one or more aquifers. “Department” means the Department of the Environment. “Development” means the process whereby a well is pumped, surged, bailed, airlifted, swabbed, or jetted to remove any material that may be blocking the well screen or fractures within the borehole. “Disinfection” means the inactivation or removal of those agents that may cause infection. “Domestic well” means a well used to supply potable water to one or more dwellings. “Driven well” means any well in which the casing is manually or mechanically driven into the ground with little or no material excavated during well construction. “Dug well” means any well made using only hand tools. “Emergency condition” means: The lack of water poses an immediate and significant danger to the health and welfare of persons, livestock, domestic fowl, or crops; or The Approving Authority has determined that other exceptional circumstances exist. “Geothermal well” means a well used to transfer heat to or from the ground or ground water. “Grout” or “grouting material” means a stable, impervious bonding material that is reasonably free of shrinkage and is capable of providing a watertight seal in the annular space throughout the depth required. “Hydrofracturing” means a method of developing or reworking an existing well whereby water is pumped down the borehole under pressure in an attempt to increase the well's yield. “Industrial well” means a well used to supply water to an industrial or commercial facility for use in processing, washing, or manufacturing of goods and services. “Injection well” means any hole made in the ground to inject fluids into any underground formation from which ground water may be produced. “Irrigation well” means a well that is used for watering crops other than residential lawns and gardens. “Jetted well” means any well made using water under pressure as a means of drilling or penetrating the ground. “Jetted-driven well” means a jetted well where the diameter of the excavation is less than the diameter of the well casing used and the well casing is driven into the excavation. “Liner” means a pipe that is installed inside a completed and cased well or borehole to: Protect the integrity of the borehole; Seal off zones of undesirable quality; Repair compromised casing or; Repair compromised screens. “Monitoring well” means a permanent well used for: Determining the water table; Determining the potentiometric surface of an aquifer; Obtaining a ground water sample; or Ground water withdrawal for remediation purposes. “Non-potable well” means a well that is not used or intended to be used as a drinking water supply. “Person” means the federal government, the State, any county, municipal corporation, or other political subdivision of the State, or any of their units, an individual, receiver, trustee, guardian, executor, administrator, fiduciary, or representative of any kind, or any partnership, firm, association, public or private corporation, or any other entity. “Piezometer” means a nonpumping well of a temporary nature to measure water tables. “Pitless adapter” means a device designed for attachment to the exterior of a well casing and equipped with lateral connections designed for the attachment of pipes leading from the well for purposes of conducting water to a distribution system and allowing extension of well casing above grade. “Pitless unit” means a device designed to replace a section of casing with lateral connections designed for the attachment of pipes leading from the well for the purposes of conducting water to a distribution system and allowing extension of well casing above grade. “Pollution” means any contamination or other alteration of the physical, chemical, or biological properties of any waters of the State, including a change in temperature, taste, color, turbidity, or odor of the waters, or the discharge or deposit of any organic matter, harmful organism, or liquid, gaseous, solid, radioactive, or other substance into any waters of this State that will render the waters harmful or detrimental to: Public health, safety, or welfare; Domestic commercial, industrial, agricultural, recreational, or other legitimate beneficial uses; Livestock, wild animals, or birds; or Fish or other aquatic life. “Potable water” means water that is free from impurities in amounts sufficient to cause disease or harmful physiological effects and that conforms with the maximum contaminant levels as adopted by the United States Environmental Protection Agency and listed in 40 CFR §141, Subpart G as amended. “Public well” means a well that is used to supply water to a public water system as defined in COMAR 26.04.01. “Replacement well” means a well that is to replace any existing water supply. Reworking. “Reworking” means the rehabilitation or modification of a well. “Reworking” includes but is not limited to: Removing and replacing well screen; Placing a new screen in a well; Placing liner pipe in a well; and Redevelopment of a well. “Reworking” does not include: Increasing the diameter of a well; or Deepening of a well. “Standby well” means a water supply well that is a backup to the primarily used water supply well which meets the construction and potability standards of this chapter. “Test well” means a well used for the purpose of exploring for ground water for a water supply and used to determine aquifer properties. “Unconfined aquifer” means an aquifer that is not bounded above by a bed of distinctly lower permeability than that of the aquifer itself and contains ground water under pressure approximately equal to that of the atmosphere. This term is synonymous with the term “water table aquifer”. “Variance” means a deviation from the requirements of these regulations granted by the Department according to the provisions of Regulation .37. “Water supply well” means every type of well, except monitoring and closed loop geothermal wells. “Well” means a hole made in the ground: To explore for ground water; To obtain or monitor ground water; To inject water into any underground formation from which ground water may be produced; or To transfer heat to or from the ground or ground water, if the hole: Extends more than 20 feet below the surface of the ground; and Is not a well for obtaining geothermal resources under Environment Article, §5-601, Annotated Code of Maryland.