Bod

BOD-The amount of oxygen required by aerobic microorganisms to decompose the organic matter in a sample of water, such as that polluted by sewage. It is used as a measure of the degree of water pollution. Chemical oxygen demand (COD) is a measure of the capacity of water to consume oxygen during the decomposition of organic matter and the oxidation of inorganic chemicals such as ammonia and nitrite. COD measurements are commonly made on samples of waste waters or of natural waters contaminated by domestic or industrial wastes. Chemical oxygen demand is measured as a standardized laboratory assay in which a closed water sample is incubated with a strong chemical oxidant under specific conditions of temperature and for a particular period of time. Chemical oxygen demand is related to biochemical oxygen demand (BOD), another standard test for assaying the oxygen-demanding strength of waste waters. However, biochemicaloxygen demand only measures the amount of oxygen consumed by microbial oxidation and is most relevant to waters rich in organic matter. It is important to understand that COD and BOD do not necessarily measure the same types of oxygen consumption. For example, COD does not measure the oxygen-consuming potential associated with certain dissolved organic compounds such as acetate. Effluent: something that flows out: as a : an outflowing branch of a main stream or lake b : waste material (as smoke, liquid industrial refuse, or sewage) discharged into the environment especially when serving as a pollutant pH- An expression for the effective concentration of hydrogen ions in solution. The pH of water determines the solubility (amount that can be dissolved in the water) and biological availability (amount that can be utilized by aquatic life) of chemical constituents such as nutrients (phosphorus, nitrogen, and carbon) and heavy metals (lead, copper, cadmium, etc.). Quantitative measure of the strength of the acidity or alkalinity (see acid, base) of a solution. A stabilization pond is a large shallow excavation that receives sewage from a sewer system, the sewage so that biological processes can destroy most of the disease-causing organisms, and discharges the effluent as treated. Sometimes two or more ponds are constructed and connected by pipes. Constructing stabilization ponds requires the services of an experienced construction supervisor and surveyor. Construction involves assembling labor, materials, and tools; preparing the site; staking the pond, embankment, and pipe locations; excavating the pond; building embankments; laying pipes; and finishing embankments. TREATED SEWAGE - The liquid that flows out of a stabilization pond or series of ponds; treated sewage is safer than settled sewage and may be used to irrigate crops not intented for human comsumption. TSS- The amount of particles that suspend in a sample of water is called total suspended solids (TSS). TSS can be estimated from measurements of turbidity or transparency, but an accurate TSS measurement involves carefully weighing the amount of suspended material from a water sample. Total suspended solids (TSS) gives a measure of the turbidity of the water Dissolved Oxygen (DO or O2): The concentration of free (not chemically combined) molecular oxygen (a gas) dissolved in water, usually expressed in milligrams per liter, parts per million, or percent of saturation. Adequate concentrations of dissolved oxygen are necessary for

the life of fish and other aquatic organisms and the prevention of offensive odors. DO levels are considered the most important and commonly employed measurement of water quality and indicator of a water body's ability to support desirable aquatic life. Levels above 5 milligrams per liter (mg O 2/L) are considered optimal and most fish cannot survive for prolonged periods at levels below 3 mg O2/L. Levels below 1 mg O2/L are often referred to as hypoxic and when O2 is totally absent anoxic (often called anaerobic which technically means without air). Secondary and advanced wastewater treatment systems are generally designed to degrade organic matter to ensure adequate dissolved oxygen in waste-receiving waters Wastewater is any water that has been adversely affected in quality by anthropogenic influence. It comprises liquid waste discharged by domestic residences, commercial properties, industry, and/or agriculture and can encompass a wide range of potential contaminants and concentrations. biochemical oxygen demand (BOD): a laboratory measurement of wastewater that is one of the main indicators of the quantity of pollutants present; a parameter used to measure the amount of oxygen that will be consumed by microorganisms during the biological reaction of oxygen with organic material secondary treatment: a type of wastewater treatment used to convert dissolved and suspended pollutants into a form that can be removed, producing a relatively highly treated effluent. Secondary treatment normally utilizes biological treatment processes (activated sludge, trickling filters, etc.) followed by settling tanks and will remove approximately 85% of the BOD and TSS in wastewater. Secondary treatment for municipal wastewater is the minimum level of treatment required by the Clean Water Act. primary treatment: the first stage of wastewater treatment that removes settleable or floating solids only; generally removes 40% of the suspended solids and 30-40% of the BOD in the wastewater Rhizodegradation is the breakdown of an organic contaminant in soil through microbial activity that is enhanced by the presence of the root zone. Rhizodegradation is also known as plant-assisted degradation, plant-assisted bioremediation, plantaided in situ biodegradation, and enhanced rhizosphere biodegradation. Root-zone biodegradation is the mechanism for implementing rhizodegradation. Reeds are perennial grasses which are classically distinguished by having hollow stems and broad leaves. These grasses typically grow in wetlands, and they can be found throughout the temperate and tropical regions of the world, with some reed types growing in colder environments. Humans have been utilizing reeds for a variety of tasks from roofing to papermaking for centuries.