Acceptable is a condition in which a component is performing its intended purpose and is considered to be in an operable state.
Alkalinity refers to a wastewater’s ability, or inability, to neutralize acids.
Ammonia is a compound of nitrogen and hydrogen with the formula NH3. The main uses of ammonia are in the production of fertilizers, and it is also an ingredient in certain household glass cleaners. The form of nitrogen in septic tanks is ammonium.
Biochemical is a treatment process that combines biological treatment and chemical treatment. The two processes overlap and sometimes it is hard to distinguish which treatment activities are biological and which are chemical.
Blackwater includes flush water from toilets and urinals and wastewater from food preparation sinks. Blackwater contains relatively higher concentrations of nitrogen and human pathogens than graywater and decomposes more slowly.
Cation exchange allows contaminants in wastewater to bond with media particles to slow the rate of movement through the media and to allow uptake of nutrients by plants and microorganisms in the media.
Chemical Oxygen Demand (COD) is a measure of the amount of organic matter oxidized by a strong chemical oxidant.
Clean water is water that never comes into contacts with humans but that is discharged into the wastewater stream. Clean water sources include condensate from ice-machine drains, condensate from air conditioners and coolers, footing drains or basement drains, and water treatment devices such as water softeners, reverse osmosis units and anion exchange processes.
Demand-dosed systems deliver wastewater to the next component in the treatment train when the wastewater becomes available. A pump activates when a pre-determined volume of effluent flows into the pump tank. The flow patterns to the next component are subject to the variations in water usage patterns from the source.
Dispersion is the process by which wastewater mixes with groundwater. Dispersion dilutes the remaining contaminants but does not remove them.
Dissolved Oxygen (DO) is the concentration of oxygen dissolved in an effluent.
Endocrine disruptors include medicines, medicine metabolites, antibiotics, and chemotherapy drugs. They can seriously alter the performance of a system through their effect on the biological activity of organisms in the septic tank.
Fats, oils, and grease (FOG) in domestic wastewater will generally originate in the kitchen or bathroom. Kitchen FOG usually comes from disposing of animal- or vegetable-based food scraps down the sink and into the system. Households using garbage disposals will have 30-40% more FOG than households not using garbage disposals. Bath oils, sun tan lotions, and moisturizing creams are bathroom sources of FOG that enter the wastewater stream.
Filtration works by moving wastewater through pore spaces in various media. Physical treatment processes can remove large particles, pathogens, and suspended solids. The smaller the pore space size, the smaller the size particle or microorganism that can be physically trapped.
Flocculation usually occurs when a chemical is added to induce the process, but it essentially when suspended solids or nutrients in the wastewater are attracted to each other and form larger clumps of particulates. Flocculated particles can then be removed through sedimentation or filtration.
Flow Equalization prevents short term, high volumes of incoming flow, called surges, from forcing solids and organic material out of the treatment components. Surge or flow equalization tanks are typically designed to hold twice the normal daily flow of the home. The flow from a surge or flow equalization tank is controlled by a timer which allows the wastewater to be distributed to the next component in fixed amounts.
Graywater is the water from showers, bathtubs, handwashing lavatories, sinks that are not used for disposal of hazardous or toxic materials or for food preparation or disposal, and clothes-washing machines. It contains less pathogens and nutrients than blackwater, but still has constituents of concern.
Management is a term describing all the steps necessary to conduct operational services, including maintenance, monitoring, and compensation.
Metals are inorganic chemical compounds that are stable and resistant to decomposition. While primarily a concern in industrial discharges, they can be present in residential wastewater when strong chemicals and/or vitamins are used in the home. While some metals are essential for animal and plant nutrition, at higher levels they may be toxic. In soils, metals generally become more soluble as the pH decreases.
Mitigation is the act of fixing a system that is in failure. Fixing the system should be preceded by an evaluation of all the components (source, collection and storage, pretreatment, final treatment and dispersal) to determine the reason for the malfunction. Certain jurisdictions may require a permit before mitigation occurs.
Nitrification is the process in which ammonia is oxidized to nitrite and nitrate, in aerobic conditions. Two groups of microorganisms are involved in nitrification. Nitrosomonas oxidizes ammonia to nitrite and water. Subsequently, Nitrobacter oxidizes the nitrite ions to nitrate.
Nutrients are elements essential for the growth of living organisms. However, humans do not utilize all of the nutrients that we consume, and residual nutrients become a potential contaminant. Of particular concern are nitrogen and phosphorus.
Observation ports, also known as inspection ports, are an access point in an onsite wastewater treatment system that allow an operation and maintenance service provider to look at a buried treatment component.
Operation is the action of assessing the functionality of each component of the system while it is in service.
Persistent organic compounds are stable compounds that decompose slowly and can persist in soil and groundwater for years. Like metals, they are primarily a concern in industrial wastewater, but can be found in household solvents, cleansers, paint, and medical products.
Phosphorous is found in body wastes, food residues, fertilizers, and detergents. Primary and secondary orthophosphates (H2PO4- and HPO42-) are the forms available to plants. Phosphorous moves with the soil absorption plume but at a retarded rate. Phosphorus retardation in soil absorption areas is dependent upon sorption and precipitation reactions. It can also move in surface water or in groundwater, during erosion episodes, or under anaerobic soil conditions.
Precipitation happens when constituents in wastewater or in the media combine together to make a new compound and become heavy enough to physically settle from the effluent. Precipitation processes are important for phosphorus removal.
Replacement is the process of exchanging a component with an equivalent component.
Service is the action of performing activities such as, but not limited to, inspection, assessment, and maintenance of system components.
Time-dosed systems use an adjustable timer on a pump to control the flow of wastewater to the next treatment component. The system operator can set the timer to turn on the pump for a set amount of time to deliver only a pre-determined volume of wastewater to the next component.
Total Kjeldahl Nitrogen (TKN) is the sum of organic nitrogen and ammonia in a water body.
Total Phosphorus (TP) is a measure of all the forms of phosphorus, dissolved or particulate, present in water.
Total Solids refers to matter suspended or dissolved in water. It is the term used for material left in a container after evaporation and drying of a water sample. Total Solids includes both total suspended solids and total dissolved solids.
Treatment Train is the unique combination of technologies that make up an individual onsite wastewater treatment system. An example of a treatment train would be a septic tank and a soil adsorption area. All components in a treatment train require operation and maintenance.
Troubleshooting is the act of identifying and correcting sources of system malfunction.
Unacceptable is a condition in which a component is not operable. This condition indicates the need for implementing maintenance, upgrades, repairs, or further investigation.