The definitions, abbreviations, and acronyms in this section apply throughout this chapter unless the context clearly indicates otherwise.

(1) "Acute" means posing an immediate risk to human health.

(2) "ADD (average day demand)" means the total volume of water produced from all sources of supply over a calendar year divided by three hundred sixty-five.

(3) "APWA" means American Public Works Association.

(4) "ASTM" means American Society for Testing and Materials.

(5) "AWWA" means American Water Works Association.

(6) "Board" means the Washington state board of health.

(7) "Certified lab" means an analytical laboratory meeting requirements under chapters 246-390 and 173-50 WAC for one or more drinking water analytical parameters.

(8) "Coliform bacteria" means a group of rod-shaped bacteria found in the gastrointestinal tract of vertebrate animals. The presence of coliform bacteria in water is an indicator of possible fecal contamination.

(9) "Contaminant" means a substance present in drinking water which may adversely affect the health of the consumer or the aesthetic qualities of the water.

(10) "Critical water supply service area" means a geographical area characterized by a proliferation of small, inadequate water systems, or by water supply problems that threaten the present or future water quality or reliability of service in a manner that efficient and orderly development may best be achieved through coordinated planning by the water utilities in the area.

(11) "Cross-connection" means any actual or potential physical connection between a public water system or a consumer's water system and any source of nonpotable liquid, solid, or gas that could contaminate the potable water supply by backflow.

(12) "Cross-connection control plan" means a document that identifies the procedures the purveyor uses to protect the Group B system from contamination from cross-connections.

(13) "Department" means the Washington state department of health.

(14) "Disinfection" means the use of chlorine or other agent or process the department approves for killing or inactivating microbiological organisms, including pathogenic and indicator organisms.

(15) "Distribution system" means all piping components of a Group B system that serve to convey water from transmission mains linked to source, storage, and treatment facilities to the consumer excluding individual services.

(16) "Drilled well" means a well where the well hole is excavated by mechanical means such as rotary, cable tool, or auger drilling equipment.

(17) "Dwelling unit" means a structure, or unit within a structure, with independent living facilities for one or more persons that includes permanent provisions for living, sleeping, eating, cooking, and sanitation. A dwelling unit includes, but is not limited to:

(a) A single-family residence; or

(b) Each unit of an apartment building or multifamily building.

(18) "Ecology" means the Washington state department of ecology.

(19) "Equalizing storage" means the volume of storage needed to supplement supply to consumers when the peak hourly demand exceeds the total source pumping capacity.

(20) "Expanding Group B system" means a Group B system installing additions, extensions, changes, or alterations to its existing source, transmission, storage, or distribution facilities that will enable the system to increase the size of its existing service area or the number of approved service connections.

(21) "Fire flow" means the maximum rate and duration of water flow needed to suppress a fire under WAC 246-293-640 or as required under local fire protection authority standards.

(22) "Fire suppression storage" means the volume of stored water available during fire suppression activities maintaining a pressure of at least 20 psi (140 kPa) at all points throughout the distribution system, and under the condition where the designed volume of fire suppression and equalizing storage has been depleted.

(23) "Generator disconnect switch" means an electrical device that physically prevents electrical current from flowing back into the main service line.

(24) "gpm" means gallons per minute.

(25) "Group A public water system" is defined and referenced under WAC 246-290-020.

(26) "Group B public water system" or "Group B system" means a public water system that is not a Group A public water system, and is defined and referenced under WAC 246-291-005.

(27) "Guideline" means a department document assisting a purveyor in meeting a rule or statutory requirement.

(28) "GWI (groundwater under the direct influence of surface water)" means any water beneath the surface of the ground, that the department determines has the following characteristics:

(a) Presence of insects or other macroorganisms, algae, or larger-diameter pathogens such as Giardia lamblia or Cryptosporidium; or

(b) Significant and relatively rapid shifts in water conditions such as turbidity, temperature, conductivity, or pH closely correlating to weather or surface water conditions, where natural conditions cannot prevent the introduction of surface water pathogens into the source at the systems' point of withdrawal.

(29) "Health officer" means the health officer of the local health jurisdiction, or an authorized representative.

(30) "Human consumption" means the use of water for drinking, bathing, showering, handwashing, cooking, food preparation, dishwashing, ice-making, or oral hygiene.

(31) "Hydraulic analysis" means the study of the Group B system's distribution main and storage network to determine the system's present or future adequacy for providing service to consumers within the established design parameters for the system under peak flow conditions, including fire flow. The analysis establishes the adequacy of design for distribution system components such as piping, elevated storage, booster stations or similar facilities used to pump and convey water to consumers.

(32) "Infiltration gallery" means a water collection system built of perforated pipe or conduit and placed in permeable earth, for collecting shallow groundwater. An infiltration gallery is usually located close to springs, wetlands, streams, or ponds.

(33) "Intertie" means an interconnection between public water systems permitting the exchange or delivery of water between those systems.

(34) "JPR (joint plan of responsibility)" means a written agreement between the department and local health jurisdiction that:

(a) Lists the roles and responsibilities of the department and health officer for reviewing and approving Group B system designs;

(b) Provides for a level of supervision necessary to effectively achieve the responsibilities in the JPR;

(c) Is signed by an authorized representative from the department and local health jurisdiction; and

(d) Is reviewed at least once every five years and updated as needed.

(35) "kPa" means kilo pascal (Standard International units of pressure).

(36) "Local board of health" means the governing body of a county health department under chapter 70.05 RCW, or a health district under chapter 70.46 RCW.

(37) "Local health jurisdiction" means a county health department under chapter 70.05 RCW, city-county health department under chapter 70.08 RCW, or health district under chapter 70.46 RCW.

(38) "Local permitting authority" means the local building official, health officer, or authorized representative that makes determinations regarding building permits and development proposals.

(39) "MCL (maximum contaminant level)" means the maximum permissible level of a contaminant in water the purveyor delivers to any Group B system consumer, measured at the source before entry to the distribution system.

(40) "MDD (maximum day demand)" means the highest actual or estimated quantity of water that is, or is expected to be, used over a twenty-four hour period, excluding unusual events or emergencies.

(41) "mg/L" means milligrams per liter (1mg/L = 1 part per million).

(42) "ml" means milliliter.

(43) "mm" means millimeter.

(44) "Nonresidential service connection" means a connection to a public water system that provides potable water including, but not limited to a:

(a) Commercial property;

(b) Industrial property;

(c) Civic property;

(d) Municipal property;

(e) Institutional property;

(f) School;

(g) Recreational use as defined in this section; or

(h) Any other authorized use that provides potable water to a nonresidential population.

(45) "PAS" means pitless adaptor standard.

(46) "PHD (peak hourly demand)" means the maximum rate of water use, excluding fire flow that can occur within a defined service area over a continuous sixty minute time period. PHD is typically expressed in gallons per minute (gpm).

(47) "Potable" means water safe for human consumption.

(48) "Potential GWI" means a source identified by the department or local health jurisdiction as possibly under the direct influence of surface water including, but not limited to a:

(a) Well that has a screened interval fifty feet or less from the ground surface at the wellhead and is located within two hundred feet of a freshwater surface water body;

(b) Ranney well;

(c) Infiltration gallery; or

(d) Spring.

(49) "Primary MCL" means a standard based on chronic, nonacute, or acute human health effects.

(50) "psi" means pounds per square inch.

(51) "Public water system" means any system providing water for human consumption through pipes or other constructed conveyances, excluding a system serving only one single-family residence and a system with four or fewer service connections all of which serve residences on the same farm. The term includes:

(a) Collection, treatment, storage, or distribution facilities under the control of a purveyor and used primarily in connection with the system; and

(b) Collection, or pretreatment storage facilities not under the control of a purveyor, and primarily used in connection with the system.

(52) "Purveyor" means an agency, subdivision of the state, municipal corporation, firm, company, mutual or cooperative association, institution, partnership, or person or other entity owning or operating a public water system, or applying to create a public water system. Purveyor also means the authorized agents of these entities.

(53) "Ranney well" means a water well or collection system including a central chamber with horizontal perforated pipes extending out into an aquifer. The perforated pipes may extend out under a surface water body such as a lake or river.

(54) "Recreational service connection" means a connection to a public water system that provides potable water to each:

(a) Campsite; or

(b) Recreational vehicle site.

(55) "Residential service connection" means a connection to a public water system that provides potable water to a dwelling unit.

(56) "Same farm" means a parcel of land or series of parcels connected by covenants and devoted to the production of livestock or agricultural commodities for commercial purposes.

(57) "Sanitary survey" means a review, inspection, and assessment of a public water system by the department or local health jurisdiction.

(58) "SCA (sanitary control area)" is defined under WAC 246-291-125(5).

(59) "SMA (satellite system management agency)" means a person or entity approved by the department in accordance with chapter 246-295 WAC to own or operate public water systems on a regional or county-wide basis without the necessity for a physical connection between the systems.

(60) "Secondary MCL" means a standard based on factors other than health effects.

(61) "Service connection" means a residential, nonresidential, or recreational service connection as defined in this section.

(62) "Single family residence" means a structure in which one or more persons maintain a common household. A structure is not a single family residence if it is used for an activity requiring a permit or license under one or more of the following rules:

(a) Food service, chapter 246-215 WAC;

(b) Food inspection, chapter 16-165 WAC;

(c) Residential treatment facility, chapter 246-337 WAC;

(d) Transient accommodations, chapter 246-360 WAC;

(e) Assisted living facility licensing rules, chapter 388-78A WAC;

(f) Minimum licensing requirements for child care centers, chapter 170-295 WAC;

(g) School-age child care center minimum licensing requirements, chapter 170-151 WAC; or

(h) Adult family home minimum licensing requirements, chapter 388-76 WAC.

(63) "Spring" means a source of water where the aquifer comes in contact with the land surface.

(64) "Surface water" means a body of water open to the atmosphere and subject to surface runoff, including captured rainfall.

(65) "WSDOT" means Washington state department of transportation.

(66) "Water right" means a permit, claim, or other authorization, on record with or accepted by the department of ecology, authorizing the beneficial use of water in accordance with all applicable state laws.

(67) "Well site inspection" means a physical inspection of the area near an existing or proposed well location, and completion of a department or health officer-approved form that identifies the suitability of the site for a public water supply well.