020-12 Wyo. Code R. § 12-4
The following definitions supplement those contained in W.S. 35-11-103 of the Wyoming Environmental Quality Act.
(a) "Auxiliary source of supply" means any water supply on or available to the water user's system other than an approved public water supply acceptable to the water supplier.
These auxiliary waters may include water from another supplier's public potable water supply or any natural source(s), such as a well, spring, river, stream, harbor, and so forth; used waters; or industrial fluids. These waters may be contaminated or polluted, they may be objectionable or they may be from a water source which the water supplier is uncertain of sanitary control.
(b) "Average daily demand" means the total annual water use divided by the number of days the system was in operation.
(b) "Backflow" means the undesirable reversal of flow of water or mixtures of water and other liquids, gases, or other substances into the distribution system of the public water supply from any other source or sources.
(c) "Backflow incident" means any identified backflow to a public water supply distribution system or to the potable water piping within the water user's system benefitting from a water service connection to the public water supply distribution system.
(d) "Back-pressure" means a form of backflow caused when the pressure of the water users' system is greater than that of the water supply system. This could be caused by a pump, elevated tank, elevated piping, boiler, pressurized process, pressurized irrigation system, air pressure or any other cause of pressure.
(e) "Back-siphonage" means a form of backflow caused by negative or reduced pressure in the water supply system. This situation can be caused by loss of pressure due to high water demands, a line break, excessive fire fighting flows, etc.
(f) "Containment" means the practice of installing approved backflow prevention devices at the water service connection of the water user in order to protect the public water supply from any backflow from the water users system.
(g) "Contamination" means an impairment of a public water supply by the introduction or admission of any foreign substance which degrades the quality of the potable water or creates a health hazard.
(h) "Cross connection" means any actual or potential connection between a potable water supply and any other source or system through which it is possible to introduce contamination into the system.
(i) "Degree of hazard" means either a high or low hazard situation where a substance may be introduced into a public water supply through a cross connection. The degree of hazard or threat to public health is determined by a hazard classification.
(j) "Domestic services" means services using potable water for ordinary living processes and not for commercial or industrial uses, fire protection systems with antifreeze or other chemicals, heating systems, etc. Examples may include residences, churches, office buildings, schools, etc.
(k) "Dual check" means a device conforming to ASSE Standard #1024 consisting of two independently acting check valves. Dual check valves are allowed only for residential water service connections that have a low hazard potential with back pressure or backsiphonage under continuous pressure.
(l) "Groundwater source" includes all water obtained from dug, drilled, bored, jetted or driven wells; springs which are developed so that the water does not flow on the ground and protected to preclude the entrance of surface contamination; and collection wells.
(m) "Hazard classification" means a determination by a hazard classification surveyor as to high hazard or low hazard and the potential cause of backflow as either back-pressure or backsiphonage.
(n) "Hazard classification survey" means inspection of a premises to identify the potable water systems, the location of any potential cross connections to the potable water systems, the hazard of the potential backflow, the physical identification of any backflow devices or methods present and the inspection status of any backflow devices or methods. The hazard classification survey results must be recorded and certified by a qualified hazard classification surveyor.
(o) "Hazard classification surveyor" means an individual certified by the USC-Foundation for Cross-Connection Control and Hydraulic Research as Cross Connection Control Specialist, the American Association of Sanitary Engineers (ASSE) as a Cross Connection Control Surveyor, or by another state certification program approved by the administrator, or by a water distribution system operator also certified as a backflow device tester employed by the public water supplier for the service where the survey is being conducted.
(p) "High hazard" means a situation created when any substance which is or may be introduced into a public water supply poses a threat to public health through poisoning, the spread of disease or pathogenic organisms, or any other public health concern.
(q) "Isolated" when referring to cross connections means the proper approved backflow prevention devices have been installed at each point of cross connection within the water user's system. This requires the installation of an approved backflow protection device at each source of possible contamination. This type of control has the advantage of protecting health within the water user's system as well as protecting the public water supply.
(r) "Low hazard" means a situation created when any substance which is or may be introduced into a public water supply does not pose a threat to public health but which does adversely affect the aesthetic quality of the potable water.
(s) "Maximum daily demand" means the demand for water exerted on the system over a period of 24 consecutive hours, for the period during which such demand is greatest.
(t) "Maximum hour demand" means the highest single hour demand exerted on the system. This may or may not occur on the maximum day.
(u) "Mineralized water" means any water containing more than 500 mg/L total dissolved solids.
(v) "Offstream reservoir" means a facility into which water is pumped during periods of good quality and high stream flow for future release to treatment facilities.
(w) "Surface water source" includes all tributary streams and drainage basins, natural lakes and artificial reservoirs or impoundments upstream from the point of the water supply intake.
(x) "Water service connection" means any water line or pipe connected to a distribution supply main or pipe for the purpose of conveying water to a water user's system.
(y) "Water supplier" means any entity that owns or operates a public water supply, whether public or private.
(z) "Water user" means any entity, whether public or private, with a water service connection to a public water supply. The water user is also identified as a customer of a public water supply.
(aa) "Water user's system" means that portion of the user's water system between the water service connection and the point of use. This system includes all pipes, conduits, tanks, fixtures, and appurtenances used to convey, store or utilize water provided by the public water supply.
020-12 Wyo. Code R. § 12-4