Wyoming Administrative Code › Agency 037 - Engineer, State › Sub-Agency 0009 - Water Well Minimum Construction Standards › Chapter 3 - WELL CONSTRUCTION › Section 3-2 - Water Well Construction

Current through July 13, 2024
(a) The driller or
				person/entity engaged in construction of a water well shall have in their
				possession, at the well site, a copy of the approved permit or the permit
				number.
(b) Knowledge of the
				properties and depth of the producing aquifer zone, the nature of the overlying
				formations, and the proposed use of the well will dictate the type of
				construction required. The following described well types are established:
(i) Type I - Dug Wells - Dug wells are
				excavations that penetrate from the ground surface down to the
				first-encountered aquifer. Dug wells are usually simple pits, elongate
				trenches, or large diameter, lined shafts constructed by hand or using
				excavating machinery (e.g., a backhoe). A typical construction diagram for Type
				I wells is illustrated in Appendix C-l.
(ii) Type II - Natural Filter Wells - Natural
				Filter Wells are constructed to obtain water at various depths from
				unconsolidated alluvial/colluvial deposits or severely weathered rock material
				that can be effectively stabilized and developed after placement of perforated
				casing or well screen. Wells of this type are usually completed into an
				unconfined aquifer (confined, perched conditions may be encountered) and may be
				dug or constructed by jetting, boring, driving, drilling, or a combination of
				methods. Horizontal wells that drain water from very coarse sand and
				gravel-sized material and often located near streams are considered Natural
				Filter Wells. A typical construction diagram for Type II wells is illustrated
				in Appendix C-2.
(iii) Type III -
				Artificial Filter Wells - Artificial Filter Wells are also referred to as
				"gravel pack," "sand pack," or "filter pack" wells. This type of well is
				designed to obtain water from unconsolidated to poorly consolidated deposits or
				bedrock formations by placing filter pack in the annulus, opposite the
				completion interval. The filter pack (or material contained in "channel pack"
				well screen) acts as a formation stabilizer, a filter to prevent fine-grained
				material from entering the well, and also serves to increase the yield of the
				well. This type of well is constructed by boring or drilling. A typical
				construction diagram for Type III wells is illustrated in Appendix
				C-3.
(iv) Type IV - Partially-Cased
				Open Borehole Wells - Partially-Cased Open Borehole Wells are also referred to
				as "open-hole" wells. This type of well is designed to obtain water from
				consolidated formations that are stable enough to preclude the need for
				perforated casing or well screen. Overlying formations, however, are cased and
				sealed to prevent caving and cross-connection of water from vertically separate
				aquifers. Flowing wells are commonly the result of this type of well
				construction when head elevation is greater than ground surface elevation. A
				typical construction diagram for Type IV wells is illustrated in Appendix
				C-4.
(v) Type V - Fully-Cased Wells
				- Fully-Cased Wells are drilled to produce water from an aquifer containing
				multiple water-bearing intervals. Water production is achieved by screening
				and/or perforating opposite one or more of the most viable water-producing
				aquifer zones. Overlying formations are cemented or grouted off to prevent
				caving and aquifer cross-connection. Wells of this type are usually drilled
				relatively deep and generally intercept aquifers under confined conditions. A
				typical construction diagram for Type V wells is illustrated in Appendix
				C-5.
(vi) Type VI - Conversion of
				Existing Oil or Gas Wells, or Exploration Test Wells into Water Wells.
(A) Existing oil and gas wells, seismic test
				holes, or mineral exploration holes may be converted for use as water wells,
				provided that the wells can be completed to conform to minimum construction
				standards cited herein.
(B)
				Information on geologic conditions encountered in the well at the time of the
				original well drilling shall be used to determine what special construction
				standards shall be met in order to eliminate all movement of pollutants into
				the well or along the annular space. If no original geologic information is
				available, a specified borehole log suite may be required to supplement known
				information.
(C) A permit to
				appropriate ground water
must
be obtained from the
				State Engineer prior to commencing construction of the well.
(D) Before any oil or gas exploration hole or
				well is converted for use as a water well, the Wyoming Oil & Gas
				Conservation Commission should be contacted in order to comply with that
				Commission's regulations.