Sec. 401 KAR 6:001 - [Effective 7/11/2026]Definitions for 401 KAR Chapter 6

ยง 401 KAR 6:001. [Effective 7/11/2026]Definitions for 401 KAR Chapter 6

RELATES TO: KRS 223.400 - 223.460, 223.991

NECESSITY, FUNCTION, AND CONFORMITY: KRS 224.10-100, 224.70-100, and 224.70-110 authorize the cabinet to establish administrative regulations to protect water quality. KRS 223.420 requires the cabinet to promulgate administrative regulations to carry out the purposes of KRS 223.405 through 223.460. KRS 223.435 requires the cabinet to promulgate administrative regulations establishing standards of practice for water well construction. This administrative regulation establishes definitions for terms used by the cabinet in 401 KAR Chapter 6.

Section 1. Definitions.

(1) "Abandon" means to seal or plug a well or borehole to prevent entry of surface water or contaminants and to prevent mixing of water from different waterbearing formations.

(2) "Annular space" means the opening between a well-bore or excavation and the well casing or between an outer casing pipe and an inner casing pipe or liner pipe.

(3) "Aquifer" means a water-bearing formation that transmits water in sufficient quantity to supply a well.

(4) "Base flood elevation" means the elevation of surface water resulting from a flood that has a one (1) percent chance of equaling or exceeding that level in any given year.

(5) "Bedrock" means a consolidated rock exposed at the surface of the earth or overlain by unconsolidated materials or soils.

(6) "Bentonite" means a clay in the montmorillonite series with a predominance of sodium as its major cation, having the property of expanding several times its original volume if saturated, and used to seal or plug wells, well annuluses, and well bores.

(7) "Board" is defined by KRS 223.400(2).

(8) "Bridging" means the deliberate or accidental closing or plugging of a section of a drill hole or annulus, beneath which is an open borehole or unfilled annulus.

(9) "Certified well driller" means a person who has met all requirements of 401 KAR 6:320 and to whom the cabinet has issued a well driller certificate.

(10) "Certified well driller assistant" means a person who has met all requirements of 401 KAR 6:320 and to whom the cabinet has issued a well driller assistant certificate.

(11) "Confining layers" or "confining formation" means a zone of sufficiently low permeability as to impede the vertical migration of groundwater.

(12) "Consolidated formation" means a geological rock formation that has grains that are bonded together.

(13) "Construction":

(a) Means all acts necessary for obtaining groundwater by wells, including drilling or excavation of the well and installation or modification of casing; and

(b) Does not mean the installation of permanent pumps and pumping equipment.

(14) "Direct supervision" means that a certified water well driller oversees and manages the work of the water well driller's assistant, including providing specific instruction regarding the construction, modification, alteration, repair, and abandonment of a water well, but the certified water well driller is not required to provide in-person supervision at the drilling site.

(15) "Driller" means "water well driller" as defined by KRS 223.400(8).

(16) "Drilling derived waste" or "DDW" means soils, drill cuttings, drilling fluids, product-contaminated water, and decontamination rinsate.

(17) "Finished ground surface" means the final or permanent elevation of the ground surface at the site of the well or abandoned borehole.

(18) "Grout-pipe method" means that grout is placed into the borehole or annulus from bottom to top via gravity flow or by pumping through a pipe or funnel-like apparatus.

(19) "High solids sodium bentonite" means bentonite containing a minimum of thirty (30) percent solids.

(20) "Impervious" means a material that will not permit the passage of water at a rate greater than 1 x 10-7 centimeters per second (cm/sec).

(21) "Modification" means a change, replacement, or alteration of the water well.

(22) "Monitoring well" means a well constructed if the actual or intended use in whole or part is the removal of water for sampling, measuring, treating, or pumping for scientific, engineering, or regulatory purposes.

(23) "Perched" means a region in the unsaturated zone separated from an underlying aquifer where the materials are locally saturated because they overlie a confining layer.

(24) "Person" shall be defined by KRS 223.400(5).

(25) "Pit" means a hole, shaft, or cavity in the ground.

(26) "Pitless well adapter" means a device designed for attachment to one (1) or more openings through a well casing.

(27) "Pitless well unit" means an assembly that extends from the upper end of the well casing to above the finished ground surface.


(29) "Potable water" means water that complies with the requirements of 401 KAR Chapter 8, the quality of which is approved by the cabinet for human consumption.

(30) "Sealing materials" means neat cement, cement-bentonite grout, or bentonite.

(31) "Special flood zone" means an area that is subject to a one (1) percent or greater chance of flooding in any given year.

(32) "Special well types" means a well that is:

(a) Bored;

(b) Driven;

(c) Irrigation; or

(d) Radial collector.

(33) "Static water level" means the level at which water stands in a well when water is not being taken from the aquifer either by pumping or by free flow.

(34) "Unconsolidated formation" means a loose-grained, nonlithified geological formation such as soil, sand, or gravel.

(35) "Undesirable geologic formation" means a geologic formation with physical characteristics or water quality not conducive to the construction and use of a well.

(36) "Undesirable groundwater" means groundwater not suitable for human or animal consumption, irrigation, manufacturing process water, or cooling.

(37) "Water supply well" means "water well" or "well" as defined by KRS 223.400(7).

(38) "Water well driller's assistant" is defined by KRS 223.400(9).

(39) "Well unsuitable for its intended use" means a well:

(a) The use of which has been permanently discontinued;

(b) That is in such a state of disrepair that it cannot be used to supply groundwater;

(c) That presents a health or safety hazard;

(d) From which usable groundwater is not obtainable; or

(e) With boreholes that:

1. Are dry;

2. Have caved in; or

3. Are unsuitable for further development and well construction.

(35 Ky.R. 585; 797; eff. 10-8-2008; Crt eff. 9-5-2018; 46 Ky.R. 628, 1465, eff: 1/3/2020.)

STATUTORY AUTHORITY: KRS 223.420(1)(e), 223.435, 224.10-100, 224.70-100, 224.70-110

The following state regulations pages link to this page.