Texas On-Site Sewage Facilities (OSSF) Questions and Answers Plus Rationales | Instant Download Pdf 2026 Update

Aerobic is a condition where oxygen is required. Aerobic microorganisms require oxygen to live and breakdown pathogens in wastewater. 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. Anaerobic is a condition in which there is no oxygen present. Anaerobic organisms get their oxygen supply by breaking down chemical compounds that contain oxygen. Aquifer is a geological formation that can store, transmit, and yield water to a well or spring. Assimilation is the transformation of a nutrient into another form that can be digested by an organism. Biochemicalis 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. Acceptable is a condition in which a component is performing its intended purpose and is considered to be in an operable state. Adsorption 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. Biochemical Oxygen Demand (BOD5) is the amount of oxygen consumed by microbes during the decomposition of organic matter. It is an indicator of the overall strength of the wastewater. Biological oxidation occurs when bacteria break down organic matter into water and carbon dioxide (CO2). Oxidation reduces BOD5, removes pathogens, and works best under aerobic conditions. Biological processes for treatment include natural die-off, predation, biological oxidation, and mineralization. biomat A ______is the biological buildup of wastewater treating organisms on a treatment media.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.