Washington Administrative Code › Title 173 - Ecology, Department of (See also Titles 197, 317, 372, and 508) › Chapter 173-160 - Minimum standards for construction and maintenance of wells › Part ONE - GENERAL REQUIREMENTS FOR WATER WELL CONSTRUCTIO › Section 173-160-111 - What are the definitions of specific words as used in this chapter?

Current through Register Vol. 24-14, July 15, 2024
(1) "Abandoned
				well" means a well that is unmaintained or is in such disrepair that it is
				unusable or is a risk to public health and welfare.
(2) "Access port" is a 1/2- to 2-inch tapped
				hole or tube equipped with a screw cap, which provides access to the inner
				casing, for measurement of the depth to water surface. An access port also
				means a removable cap.
(3) "Annular
				space" is the space between the surface or outer casing and the inner casing,
				or the space between the wall of the drilled hole and the casing.
(4) "Aquifer" is a geologic formation, group
				of formations, or part of a formation capable of yielding a significant amount
				of groundwater to wells or springs.
(5) "Artesian well" is a well tapping an
				aquifer bounded above and below by confining or impermeable rock or soil
				layers, or rock or soil layers of distinctly lower permeability than the
				aquifer itself. The water will rise in the well above the point of initial
				penetration (above the bottom of the confining or impermeable layer overlying
				the aquifer). This term includes both flowing and nonflowing wells.
(6) "Artificial gravel pack" is a mixture of
				gravel or sand placed in the annular space around the liner, perforated pipe,
				or well screen. A gravel pack is used to reduce the movement of finer material
				into the well and provide lateral support to the screen in unstable
				formations.
(7) "Artificial
				recharge" is the addition of water to an aquifer by activities of man, such as
				irrigation or induced infiltration from streams, or injection through wells,
				trenches, pits, and ponds.
(8)
				"Bentonite" is a mixture of swelling clay minerals, predominantly sodium
				montmorillonite.
(9) "Building
				drain" means that part of the lowest piping of a drainage system which receives
				the discharge from soil, waste, and other drainage pipes inside the walls of
				the building and conveys it to the building sewer beginning two feet outside
				the building wall.
(10) "Building
				sewer" means that part of the horizontal piping of a drainage system which
				extends from the end of the building drain and which receives the discharge of
				the building drain and conveys it to a public sewer, private sewer, individual
				sewage disposal system, or other point of disposal.
(11) "Capped well" is a well that is not in
				use and has a watertight seal or cap installed on top of the casing.
(12) "Casing" is a pipe, generally made of
				metal or plastic, which is installed in the bore hole as part of the drilling
				process to maintain the opening. Casing may be utilized in either consolidated
				or unconsolidated formations and must meet the requirements of WAC
				173-160-201.
(13) "Confining layer" or "confining
				formation" means a layer of low hydraulic conductivity material that
				significantly limits vertical movement of groundwater.
(14) "Consolidated formation" means any
				geologic formation in which the earth materials have become firm and cohesive
				through natural rock forming processes. Such rocks commonly found in Washington
				include basalt, granite, sandstone, shale, conglomerate, and
				limestone.
(15) "Constructing a
				well" or "construct a well" means:
(a) Boring,
				digging, drilling, or excavating a well;
(b) Installing casing, sheeting, lining, or
				well screens, in a well;
(c)
				Drilling a geotechnical soil boring;
(d) Installing an environmental investigation
				well; or
(e) Alteration of an
				existing well.