OAR 333-061-0020: Definitions

As used in these rules, unless the context indicates otherwise: (1) "Act" means the Oregon Drinking Water Quality Act of 1981 (ORS 448.115-448.990 as amended). (2) "Action Level" or “AL” means the concentration of lead or copper in water which determines, in some cases, the treatment requirements that a water system is required to complete. (3) "Administrator" means the Director of the Oregon Health Authority or his/her designee. (4) "Approval" or "Approved" means approved in writing. (5) "Approved Air Gap" means a physical separation between the free-flowing discharge end of a potable water supply pipeline and an open or non-pressurized receiving vessel. An "Approved Air Gap" shall be at least twice the diameter of the supply pipe measured vertically above the overflow rim of the vessel and in no case less than 1 inch (2.54 cm), and in accord with Oregon Plumbing Specialty Code. (6) "Approved Backflow Prevention Assembly" means a Reduced Pressure Principle Backflow Prevention Assembly, RPDA, Double Check Valve Backflow Prevention Assembly, Double Check-Detector Backflow Prevention Assembly, Pressure Vacuum Breaker Backsiphonage Prevention Assembly, or Spill-Resistant Pressure Vacuum Breaker Backsiphonage Prevention Assembly, of a make, model, orientation, and size approved by the Authority. Assemblies listed in the currently approved backflow prevention assemblies list developed by the University of Southern California, Foundation for Cross-Connection Control and Hydraulic Research, or other testing laboratories using equivalent testing methods, are considered approved by the Authority. (7) "Aquifer" means a water saturated and permeable geological formation, group of formations, or part of a formation that is capable of transmitting water in sufficient quantity to supply wells or springs. (8) "Atmospheric Vacuum Breaker" or "AVB" means a non-testable device consisting of an air inlet valve or float check, a check seat and an air inlet port(s). This device is designed to protect against a non-health hazard or a health hazard under a backsiphonage condition only. Product and material approval is under the Oregon Plumbing Specialty Code. (9) "Authority" means the Oregon Health Authority or its designee. (10) "AWWA" means the American Water Works Association. (11) "Backflow" means the flow of water or other liquids, mixtures, or substances into the distributing pipes of a potable supply of water from any sources other than its intended source, and is caused by backsiphonage or backpressure. (12) "Backflow Prevention Assembly" means a backflow prevention assembly such as a Pressure Vacuum Breaker Backsiphonage Prevention Assembly, Spill-Resistant Pressure Vacuum Breaker Backsiphonage Prevention Assembly, Double Check Valve Backflow Prevention Assembly, Double Check-Detector Backflow Prevention Assembly, Reduced Pressure Principle Backflow Prevention Assembly, or Reduced Pressure Principle-Detector Backflow Prevention Assembly and the attached shutoff valves on the inlet and outlet ends of the assembly, assembled as a complete unit. (13) "Backpressure" means an elevation of pressure downstream of the distribution system that would cause, or tend to cause, water to flow opposite of its intended direction. (14) "Backsiphonage" means a drop in distribution system pressure below atmospheric pressure (partial vacuum), that would cause, or tend to cause, water to flow opposite of its intended direction. (15) "Bank Filtration" means a water treatment process that uses a horizontal or vertical well to recover surface water that has naturally infiltrated into groundwater through a river bed or bank(s). Infiltration is typically enhanced by the hydraulic gradient imposed by a nearby pumping water supply. (16) "Best Available Technology" or "BAT" means the best technology, treatment techniques, or other means which the U.S. EPA finds, after examination for efficacy under field conditions and not solely under laboratory conditions, are available (taking cost into consideration). (17) "Bottled Water" means potable water from a source approved by the Authority for domestic use which is placed in small, easily transportable containers. (18) "Calculated Fixed Radius" means a technique to delineate a wellhead protection area, based on the determination of the volume of the aquifer needed to supply groundwater to a well over a given length of time. (19) "CFR" means the Code of Federal Regulations. Specifically, it refers to those sections of the code which deal with the National Primary and Secondary Drinking Water Regulations. (20) "Check Valve" means a valve, which allows flow in only one direction. (21) "Coagulation" means a process using coagulant chemicals and mixing by which colloidal and suspended materials are destabilized and agglomerated into floc. (22) "Coliform Investigation" means an evaluation to identify the possible presence of sanitary defects, defects in distribution system coliform monitoring practices, and (when possible) the likely reason that the investigation was triggered at the water system. Coliform investigations are classified as level 1 or level 2 as prescribed by OAR 333-061-0078. (23) "Coliform-Positive" means the presence of coliform bacteria in a water sample. (24) "Combined distribution system" means the interconnected distribution system consisting of the distribution systems of wholesale water systems and of the purchasing water systems that receive finished water. (25) "Community Water System" means a public water system that has 15 or more service connections used by year-round residents, or that regularly serves 25 or more year-round residents. (26) "Compliance Cycle" means the nine-year calendar year cycle during which public water systems must monitor. Each compliance cycle consists of three three-year compliance periods. The first calendar year cycle begins January 1, 1993 and ends December 31, 2001. (27) "Compliance Period" means a three-year calendar year period within a compliance cycle. Each compliance cycle has three three-year compliance periods. Within the first compliance cycle, the first compliance period runs from January 1, 1993 to December 31, 1995; the second from January 1, 1996 to December 31, 1998; and the third from January 1, 1999 to December 31, 2001. (28) "Comprehensive performance evaluation" or "CPE" means a thorough review and analysis of a treatment plant's performance-based capabilities and associated administrative, operation and maintenance practices. It is conducted to identify factors that may be adversely impacting a plant's capability to achieve compliance and emphasizes approaches that can be implemented without significant capital improvements. The CPE must consist of at least the following components: Assessment of plant performance; evaluations of major unit processes; identification and prioritization of performance limiting factors; assessment of the applicability of comprehensive technical assistance; and preparation of a CPE report. (29) "Connection." See "Service Connection." (30) "Constructed Conveyance" means any human-made conduit such as ditches, culverts, waterways, flumes, mine drains, canals or any human-altered natural water bodies or waterways as determined by the Authority. (31) "Contaminant" means any physical, chemical, biological, or radiological substance or matter in water. (32) "Contingency Plan" means a document setting out an organized, planned and coordinated course of action to be followed in the event of a loss of capacity to supply water to the distribution system or in case of a fire, explosion or release of hazardous waste which could threaten human health or the environment. (33) "Continuing Education Unit" or "CEU" means a nationally recognized unit of measurement for assigning credits for education or training that provides the participant with advanced or post high school learning. One CEU is awarded for every 10 classroom hours of lecture or the equivalent of participation in an organized education experience, conducted under responsible sponsorship, capable direction and qualified instruction as determined by the Authority or its designee. (34) "Corrosion Inhibitor" means a substance capable of reducing the corrosivity of water toward metal plumbing materials, especially lead and copper, by forming a protective film on the interior surface of those materials. (35) "Cross Connection" means any actual or potential unprotected connection or structural arrangement between the public or user's potable water system and any other source or system through which it is possible to introduce into any part of the potable system any used water, industrial fluid, gas, or substances other than the intended potable water with which the system is supplied. Bypass arrangements, jumper connections, removable sections, swivel, or change-over devices, and other temporary or permanent devices through which, or because of which, backflow can occur are considered to be cross connections. (36) "CT" means the product of the residual disinfectant concentration "C" (measured in mg/l) and disinfectant contact time(s), "T" (measured in minutes). (37) "Degree of Hazard" means either pollution (non-health hazard) or contamination (health hazard) and is determined by an evaluation of hazardous conditions within a system. (38) "Delineation" means the determination of the extent, orientation and boundaries of a wellhead protection area using factors such as geology, aquifer characteristics, well pumping rates and time of travel. (39) "Demonstration Study" means a series of tests performed to prove an overall effective removal or inactivation rate of a pathogenic organism through a treatment or disinfection process. (40) "Direct Responsible Charge" or "DRC" means an individual designated by the owner or authorized agent to make decisions regarding the daily operational activities of a public water system, water treatment facility or distribution system, that will directly impact the quality or quantity of drinking water. (41) "Disinfectant Contact Time" means the time in minutes that it takes for water to move from the point of disinfectant application or the previous point of disinfection residual measurement to a point before or at the point where residual disinfectant concentration is measured. (42) "Disinfectant Residual Maintenance" means a process where chlorine or another chemical is added to the water supply at a public water system for the purpose of maintaining a disinfectant residual in the distribution system. (43) "Disinfection" means a process by which a chemical or ultraviolet light is used to inactivate pathogenic organisms in water. Disinfection intended to inactivate one or more pathogens in source water is referred to as disinfection for pathogen inactivation and is characterized by monitoring to verify the inactivation achieved. (44) "Disinfection profile" means a summary of Giardia lamblia inactivation through the treatment plant. (45) "Distribution System" means that portion of the water system in which water is stored or conveyed from the water treatment plant or other supply point to the premises of a consumer. (46) "Domestic" means provided for human consumption. (47) "Dose Equivalent" means the product of the absorbed dose from ionizing radiation and such factors as account for differences in biological effectiveness due to the type of radiation and its distribution in the body as specified by the International Commission on Radiological Units and Measurements. (48) "Double Check-Detector Backflow Prevention Assembly" or "DCDA" means a specially designed assembly composed of a line size approved double check valve assembly assembled with a bypass containing a specific water meter and an approved double check valve assembly. The meter shall register accurately for only very low rates of flow up to three gallons per minute and shall show a registration for all rates of flow. This assembly is designed to protect against a non-health hazard. (49) "Double Check Valve Backflow Prevention Assembly" or "DC" means an assembly of two independently acting approved check valves, including tightly closing resilient seated shutoff valves attached at each end of the assembly and fitted with properly located resilient seated test cocks. This assembly is designed to protect against a non-health hazard. (50) "Drawdown" means the difference, measured vertically, between the static water level in the well and the water level during pumping. (51) "Drinking Water Protection" means implementing strategies within a drinking water protection area to minimize the potential impact of contaminant sources on the quality of water being used as a drinking water source by a Public Water System. (52) "Drinking Water Protection Area" or "DWPA" means the source area supplying drinking water to a Public Water System. For a surface water-supplied drinking water source the DWPA is all or a specifically determined part of a lake's, reservoir's or stream's watershed that has been certified by the Department of Environmental Quality. For a groundwater-supplied drinking water source the DWPA is the area on the surface that directly overlies that part of the aquifer that supplies groundwater to a well, well field or spring that has been certified by the Authority. (53) "Drinking Water Protection Plan" means a plan, certified by the Department of Environmental Quality according to OAR 340-040-0160 to 340-040-0180, which identifies the actions to be taken at the local level to protect a specifically defined and certified DWPA. The plan is developed by the local Responsible Management Authority or team and includes a written description of each element, public participation efforts, and an implementation schedule. (54) "Dual sample set" means a set of two samples collected at the same time and same location, with one sample analyzed for TTHM and the other for HAA5. Dual sample sets are collected for the purposes of conducting an Initial Distribution System Evaluation (IDSE) as prescribed in 333-061-0036(4)(b) of these rules, and for determining compliance with the MCLs for TTHM and HAA5 listed in OAR 333-061-0030(2)(b). (55) "Emergency" means a condition resulting from an unusual calamity such as a flood, storm, earthquake, drought, civil disorder, volcanic eruption, an accidental spill of hazardous material, or other occurrence which disrupts water service at a public water system or endangers the quality of water produced by a public water system. (56) "Emergency Response Plan" means a written document establishing contacts, operating procedures, and actions taken for a public water system to minimize the impact or potential impact of a natural disaster, accident, or intentional act which disrupts or damages, or potentially disrupts or potentially damages the public water system or drinking water supply, and returns the public water system to normal operating condition. (57) "Enhanced coagulation" means the addition of sufficient coagulant for improved removal of disinfection byproduct precursors by conventional filtration treatment. (58) "Enhanced softening" means the improved removal of disinfection byproduct precursors by precipitative softening. (59) "EPA" means the United States Environmental Protection Agency. (60) "Filtration" means a process for removing particulate matter from water through porous media. (a) "Bag filtration" means a pressure-driven separation process that removes particulate matter using engineered media. It is typically constructed of a non-rigid, fabric filtration media housed in a pressure vessel in which the direction of flow is from the inside of the bag to the outside. (b) "Cartridge filtration" means a pressure-driven separation process that removes particulate matter using engineered media. It is typically constructed of rigid or semi-rigid, self-supporting filter elements housed in a pressure vessel in which flow is from the outside of the cartridge to the inside. (c) "Conventional Filtration Treatment" means a series of processes including coagulation (requiring the use of a primary coagulant and rapid mix), flocculation, sedimentation, and filtration resulting in substantial particulate removal. (d) "Direct Filtration Treatment" means a series of processes including coagulation (requiring the use of a primary coagulant and rapid mix) and filtration but excluding sedimentation resulting in substantial particulate removal. (e) "Diatomaceous Earth Filtration" means a process resulting in substantial particulate removal in which: (A) A precoat cake of diatomaceous earth filter media is deposited on a support membrane (septum); and (B) While the water is filtered by passing through the cake on the septum, additional filter media, known as body feed, is continuously added to the feed water, in order to maintain the permeability of the filter cake. (f) "Membrane filtration" means a pressure or vacuum driven separation process in which particulate matter larger than one micrometer is rejected by engineered media, primarily through a size-exclusion mechanism, and which has a measurable removal efficiency of a target organism that can be verified through the application of a direct integrity test. This definition includes the common membrane technologies of microfiltration, ultrafiltration, nanofiltration, and reverse osmosis. (g) "Slow Sand Filtration" means a process involving passage of raw water through a bed of sand at low velocity (generally less than 235 gallons per square foot per day) resulting in substantial particulate removal by both physical and biological mechanisms. (61) "Filtration Endorsement" means a special certification that may be added to an operator's water treatment level 2 certification, and is related to the operator’s experience with and knowledge of the operation of conventional and direct filtration treatment. (62) "Finished water" means water that is introduced into the distribution system of a public water system and intended for distribution and consumption without further treatment, except as necessary to maintain water quality in the distribution system such as booster disinfection or the addition of corrosion control chemicals. (63) "First Customer" means the initial service connection or tap on a public water supply after any treatment processes. (64) "Flocculation" means a process to enhance agglomeration or collection of smaller floc particles into larger, more easily settleable particles through gentle stirring by hydraulic or mechanical means. (65) "GAC" means granular activated carbon. (66) "Gross Alpha Particle Activity" means the total radioactivity due to alpha particle emission as inferred from measurements on a dry sample. (67) "Gross Beta Particle Activity" means the total radioactivity due to beta particle emission as inferred from measurements on a dry sample. (68) "Groundwater" means any water, except capillary moisture, beneath the land surface or beneath the bed of any stream, lake, reservoir or other body of surface water within the boundaries of this state, whatever may be the geologic formation or structure in which such water stands, flows, percolates or otherwise moves. (69) "Groundwater System" means any public water system that uses groundwater, including purchasing water systems that receive finished groundwater, but excluding public water systems that combine all of their groundwater with surface water or groundwater under the direct influence of surface water prior to treatment. (70) "Groundwater under the direct influence of surface water" or "GWUDI" means any water beneath the surface of the ground with significant occurrence of insects or other macro-organisms, algae or large-diameter pathogens such as Giardia lamblia or Cryptosporidium , or significant and relatively rapid shifts in water characteristics such as turbidity, temperature, conductivity, or pH which closely correlate to climatological or surface water conditions. (71) "Haloacetic acids (five)" or "HAA5" means the sum of the concentrations in milligrams per liter of the haloacetic acid compounds (monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid), rounded to two significant figures after addition. (72) "Health Hazard (Contamination)" means an impairment of the quality of the water that could create an actual hazard to the public health through poisoning or through the spread of disease by sewage, industrial fluids, waste, or other substances. (73) "Human Consumption" means water used for drinking, personal hygiene bathing, showering, cooking, dishwashing, and maintaining oral hygiene. (74) "Hydraulic Gradient" means the slope of the water table or potentiometric surface, calculated by dividing the change in hydraulic head between two points by the horizontal distance between the points in the direction of groundwater flow. (75) "Hydraulic Head" means the energy possessed by the water mass at a given point, related to the height above the datum plane that water resides in a well drilled to that point. In a groundwater system, the hydraulic head is composed of elevation head and pressure head. (76) "Infiltration Gallery" means a system of perforated pipes laid along the banks or under the bed of a stream or lake installed for the purpose of collecting water from the formation beneath the stream or lake. (77) "Lead Free" means: (a) Not containing more than 0.2 percent lead when used with respect to solders and flux; and (b) Not more than a weighted average of 0.25 percent lead when used with respect to the wetted surfaces of pipes, pipe fittings, plumbing fittings, and fixtures. (78) " Legionella " means a genus of bacteria, some species of which have caused a type of pneumonia called Legionnaires Disease. (79) "Local Administrative Authority" means the individual official, board, department or agency established and authorized by a state, county or city to administer and enforce the provisions of the Oregon State Plumbing Specialty Code adopted under OAR 918-750-0110. (80) "Locational running annual average" or "LRAA" means the arithmetic average of analytical results for samples taken at a specific monitoring location during the previous four calendar quarters. (81) "Major Additions or Modifications" means changes of considerable extent or complexity including, but not limited to, projects involving water sources, treatment or disinfection facilities, finished water storage, pumping facilities, transmission mains, and distribution mains, except main replacements of the same length and diameter. (82) "Master Plan" means an overall plan, which shows the projected development of a distribution system and alternatives for source development. (83) "Maximum Contaminant Level" or "MCL" means the maximum allowable level of a contaminant in water delivered to the users of a public water system. (84) "Maximum Residual Disinfectant Level" or "MRDL" means a level of a disinfectant added for water treatment that may not be exceeded at the consumer's tap without an unacceptable possibility of adverse health effects. The MRDLs for chlorine, chloramines and chlorine dioxide are identified in OAR 333-061-0031. (85) "Non-Health Hazard (Pollution)" means an impairment of the quality of the water to a degree that does not create a hazard to the public health, but does adversely affect the aesthetic qualities of such water for potable use. (86) "Non-Transient Non-Community Water System" or "NTNC" means a public water system that regularly serves at least 25 of the same persons over 6 months per year. (87) "Operating Experience" means knowledge gained through the direct performance of duties, tasks, and responsibilities at a drinking water system or in a related field. (88) "Operational Decision Making" means the act of making decisions about alternatives in the performance of a water treatment plant or distribution system relating to water quality or water quantity that may affect public health. (89) "Operator," means a person responsible for the operation of a water treatment plant or distribution system. (90) "Optimal Corrosion Control Treatment" means the corrosion control treatment that minimizes the lead and copper concentrations at users' taps while ensuring that the treatment does not cause the water system to violate any national primary drinking water regulations. (91) "Oregon Very Small Water System" means a public water system, which serves 4 to 14 service connections or that serves commercial or public premises which are used by 10 to 24 people at least 60 days per year. (92) "Pathogenic" means a specific agent (bacterium, virus or parasite) causing or capable of causing disease. (93) "Permit" means official permission granted by the Authority for a public water system which exceeds maximum contaminant levels to delay, because of economic or other compelling factors, the installation of water treatment facilities which are necessary to produce water which does not exceed MCLs. (94) "Person" means any individual, corporation, association, firm, partnership, municipal, state or federal agency, or joint stock company and includes any receiver, special master, trustee, assignee, or other similar representative thereof. (95) "Picocurie" or "pCi" means that quantity of radioactive material producing 2.22 nuclear transformations per minute. (96) "Point of Delivery" or "POD" means the point of connection between a public water system and the user's water system. Beyond the POD, the Oregon Plumbing Specialty Code applies. See "Service Connection." (97) "Point of Disinfectant Application" is the point where the disinfectant is applied and water downstream of that point is not subject to recontamination by surface water runoff. (98) "Point-of-Entry Treatment Device" is a treatment device applied to the drinking water entering a house or building for the purpose of reducing contaminants in the drinking water distributed throughout the house or building. (99) "Point-of-Use Treatment Device" is a treatment device applied to a single tap used for the purpose of reducing contaminants in drinking water at that one tap. (100) "Potable Water." See Safe Drinking Water. (101) "Potential Contaminant Source Inventory" means the determination of the location within the wellhead protection area of activities known to use or produce materials that can contaminate groundwater. (102) "Potential Cross Connection" means a cross connection that would most likely occur, but may not be taking place at the time of an inspection. (103) "Potentiometric Surface" means a surface that denotes the variation of hydraulic head in the given aquifer across an area. (104) "Premises" means real estate and the structures on it. (105) "Premises Isolation" means the practice of protecting the public water supply from contamination or pollution by installing backflow prevention assemblies at, or near, the POD where the water supply enters the premises. Premises isolation does not guarantee protection to persons on the premises. (106) "Presedimentation" means a preliminary treatment process used to remove gravel, sand and other particulate material from the source water through settling before the water enters the primary clarification and filtration processes in a treatment plant. (107) "Pressure Vacuum Breaker Backsiphonage Prevention Assembly" or "PVB" means an assembly consisting of an independently operating, internally loaded check valve and an independently operating loaded air inlet valve located on the discharge side of the check valve. This assembly is to be equipped with properly located resilient seated test cocks and tightly closing resilient seated shutoff valves attached at each end of the assembly. This assembly is designed to protect against a non-health hazard or a health hazard under backsiphonage conditions only. (108) "Public Health Hazard" means a condition, device or practice which is conducive to the introduction of waterborne disease organisms, or harmful chemical, physical, or radioactive substances into a public water system, and which presents an unreasonable risk to health. (109) "Public Water System" means a system for the provision to the public of piped water for human consumption, if such system has more than three service connections, or supplies water to a public or commercial establishment that operates a total of at least 60 days per year, and that is used by 10 or more individuals per day. Public water system also means a system for the provision to the public of water through constructed conveyances other than pipes to at least 15 service connections or regularly serves at least 25 individuals daily at least 60 days of the year. A public water system is either a "Community Water System," a "Transient Non-Community Water System," a "NTNC Water System" or an "Oregon Very Small Water System." (110) "Purchasing Water System" means a public water system which obtains its water in whole or in part from one or more public water systems. Delivery may be through a direct connection or through the distribution system of one or more purchasing water systems. (111) "Recharge" means the process by which water is added to a zone of saturation, usually by downward infiltration from the surface. (112) "Reduced Pressure Principle Backflow Prevention Assembly" or "RP" means an assembly containing two independently acting approved check valves, together with a hydraulically operating, mechanically independent pressure differential relief valve located between the check valves and at the same time below the first check valve. The unit shall include properly located resilient seated test cocks and tightly closing resilient seated shutoff valves at each end of the assembly. This assembly is designed to protect against a non-health hazard or a health hazard. (113) "Reduced Pressure Principle-Detector Backflow Prevention Assembly" or "RPDA" means a specifically designed assembly composed of a line size approved RP with a bypass containing a specific water meter and an approved RP. The meter shall register accurately for only very low rates of flow up to three gallons per minute and shall show a registration for all rates of flow. This assembly is designed to protect against a non-health hazard or a health hazard. (114) "Rem" means the unit of dose equivalent from ionizing radiation to the total body or any internal organ or organ system. A "millirem" or "mrem)" is 1/1000 of a rem. (115) "Residual disinfectant concentration" means the concentration of disinfectant measured in mg/l in a representative sample of water. (116) "Responsible Management Authority" means the Public Water System whose water supply is being protected and any government entity having management, rule or ordinance-making authority to implement wellhead protection management strategies within the wellhead protection area. The Responsible Management Authority is responsible for implementation of the Wellhead Protection Plan and includes cities, counties, special districts, Indian tribes, state/federal entities as well as public water systems. (117) "Safe Drinking Water" means water which has sufficiently low concentrations of microbiological, inorganic chemical, organic chemical, radiological or physical substances so that individuals drinking such water at normal levels of consumption, will not be exposed to disease organisms or other substances which may produce harmful physiological effects. (118) "Sanitary Defect" means a defect that could provide a pathway of entry for microbial contamination into the distribution system or that is indicative of a failure or imminent failure in a barrier that is already in place. (119) "Sanitary Survey" or "Water System Survey" means an on-site review of the water source(s), facilities, equipment, operation, maintenance and monitoring compliance of a public water system to evaluate the adequacy of the water system, its sources and operations in the distribution of safe drinking water. The sanitary survey also identifies sources of contamination by using the results of source water assessments where available. (120) "Seasonal water system" means a water system operated as a non-community public water system only part of each year and that is started up at the beginning and shut down at the end of each operating season. (121) "Secondary Contaminant" means those contaminants, which, at the levels generally found in drinking water, do not present an unreasonable risk to health, but do: (a) Have adverse effects on the taste, odor and color of water; (b) Produce undesirable staining of plumbing fixtures; or (c) Interfere with treatment processes applied by water suppliers. (122) "Secondary Maximum Contaminant Level" or "SMCL" means the level of a secondary contaminant which when exceeded may adversely affect the aesthetic quality of the drinking water which thereby may deter public acceptance of drinking water provided by public water systems or may interfere with water treatment methods. (123) "Sedimentation" means a process for removal of solids before filtration by gravity or separation. (124) "Service Connection" means the piping connection through which water is conveyed from a public water system to a user's premises. (125) "Significant Deficiency" means a defect in design, operation, or maintenance, or a malfunction of the source(s), treatment, storage, or distribution system that has been determined to cause or have the potential for causing the introduction of contamination into the water delivered to consumers. (126) "Small Water System Certification," for the purposes of OAR 333-061-0220 and 0228, means operator certification for a community or NTNC water system serving 150 service connections or less and that uses only groundwater sources or purchases finished water from another public water system. (127) "Source Water Assessment" means the information compiled by the Authority and the Department of Environmental Quality (DEQ), consisting of the delineation, inventory and susceptibility analyses of the drinking water source, which enable public water systems to develop and implement drinking water protection plans. (128) "Specific Ultraviolet Absorption" or "SUVA" means an indicator of the humic content of water as a calculated parameter obtained by dividing a sample's ultraviolet absorption at a wavelength of 254 nanometers by its concentration of dissolved organic carbon in milligrams per liter. (129) "Spill Resistant Pressure Vacuum Breaker Backsiphonage Prevention Assembly" or "SVB" means an assembly containing an independently operating, internally loaded check valve and independently operating loaded air inlet valve located on the discharge side of the check valve. The assembly is to be equipped with a properly located resilient seated test cock, a properly located bleed/vent valve, and tightly closing resilient seated shutoff valves attached at each end of the assembly. This assembly is designed to protect against a non-health hazard or a health hazard under a backsiphonage condition only. (130) "Spring" means a naturally occurring discharge of flowing water at the ground surface, or into surface water where the flow of water is the result of gravity or artesian pressure. Springs can be derived from groundwater or they can be surface water influenced. (131) "Static Water Level" means the vertical distance from ground surface to the water level in the well when the well is at rest, that is, the well has not been pumped recently and the water level is stable. This is the natural level of water in the well. (132) "Surface Water" means all water, which is open to the atmosphere and subject to surface runoff. (133) "Susceptibility" means the potential, as a result of the combination of land use activities and source water sensitivity, that contamination of the drinking water source may occur. (134) "Team" means the local Wellhead Protection team, which includes representatives from the Responsible Management Authorities and various interests and stakeholders potentially affected by the Wellhead Protection Plan. (135) "These rules" means the Oregon Administrative Rules encompassed by OAR 333-061-0005 through 333-061-0335. (136) "Time-of-Travel" or "TOT" means the amount of time it takes groundwater to flow to a given well. TOT is the criterion that effectively determines the radius in the calculated fixed radius method and the up-gradient distance to be used for the analytical and numerical models during delineation of the wellhead protection area. (137) "Total Organic Carbon" or "TOC" means total organic carbon in milligrams per liter measured using heat, oxygen, ultraviolet irradiation, chemical oxidants, or combinations of these oxidants that convert organic carbon to carbon dioxide, rounded to two significant figures. (138) "Total Trihalomethanes" or "TTHM" means the sum of the concentrations in milligrams per liter of the trihalomethane compounds bromodichloromethane, dibromochloromethane, tribromomethane (bromoform) and trichloromethane (chloroform), rounded to two significant figures after addition. (139) "Transient Non-Community Water System" or "TNC" means a public water system that serves a transient population of 25 or more persons. (140) "Turbidity" means a measure of the cloudiness of water caused by suspended particles. The units of measure for turbidity are nephelometric turbidity units (NTU). (141) "Two-stage lime softening" means a process in which a chemical addition and hardness precipitation occur in each of two distinct unit clarification processes in series prior to filtration. (142) "Uncovered finished water storage facility" means a tank, reservoir, or other facility used to store water that will undergo no further treatment to reduce microbial pathogens except residual disinfection and is directly open to the atmosphere. (143) "Vadose Zone" means the zone between the ground surface and the water table where the available open spaces between soil and sediment particles, in rock fractures, etc., are most filled with air. (144) "Variance" means official permission granted by the Authority for public water systems to exceed MCLs because the quality of the raw water is such that the best available treatment techniques are not capable of treating the water so that it complies with MCLs, and there is no unreasonable risk to health. (145) "Vault" means an approved enclosure above or below ground to house a backflow prevention assembly that complies with the local administrative authority having jurisdiction. (146) "Virus" means a virus of fecal origin, which is infectious to humans by waterborne transmission. (147) "Vulnerability" has the same meaning as susceptibility. (148) "Waiver" means official permission from the Authority for a public water system to deviate from the construction standards set forth in these rules. (149) "Waterborne disease outbreak" means the significant occurrence of acute infectious illness, epidemiologically associated with the ingestion of water from a public water system which is deficient in treatment, as determined by the Authority. (150) "Water Source" means any lake, stream, spring, groundwater supply, impoundment or other source of water from which water is obtained for a public water system. In some cases, a public water system can be the source of supply for one or more other public water systems. (151) "Water Supplier" means a person, group of persons, municipality, district, corporation or other entity, which owns or operates a public potable water system. (152) "Water System" means a system for the provision of piped water for human consumption. (153) "Water System Operations Manual" means a written document describing the actions and procedures necessary to operate and maintain the entire water system. (154) "Water Table" means the upper surface of an unconfined aquifer, the surface of which is at atmospheric pressure and fluctuates seasonally. It is defined by the levels at which water stands in wells that penetrate the aquifer. (155) "Water Treatment" means a process of altering water quality by physical or chemical means and may include domestic, industrial or commercial applications. (156) "Water Treatment Plant" means that portion of a water system that in some way alters the physical, chemical, or bacteriological quality of the water being treated. (157) "Well" means an artificial opening or artificially altered natural opening, however made, by which ground water is sought or through which ground water flows under natural pressure or is artificially withdrawn or injected, provided that this definition shall not include a natural spring, or wells drilled for the purpose of exploration or production of oil or gas. (158) "Wellfield" means two or more drinking water wells, belonging to the same water system that are within 2,500 feet, or as determined by the Authority, and produce from the same and no other aquifer. (159) "Wellhead Protection." See Drinking Water Protection. (160) "Wellhead Protection Area" or "WHPA." See Drinking Water Protection Area. (161) "Wellhead Protection Plan." See Drinking Water Protection Plan. (162) "Wholesale system" means a public water system that treats source water as necessary to produce finished water and then delivers some or all of that finished water to another public water system. Delivery may be through a direct connection or through the distribution system of one or more purchasing water systems.