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United States Regulation Of Point Source Water Pollution
Point source water pollution comes from discrete conveyances and alters the chemical, biological, and physical characteristics of water. In the United States, it is largely regulated by the Clean Water Act (CWA). Among other things, the Act requires dischargers to obtain a National Pollutant Discharge Elimination System (NPDES) permit to legally discharge pollutants into a water body. However, point source pollution remains an issue in some water bodies, due to some limitations of the Act. Consequently, other regulatory approaches have emerged, such as water quality trading and voluntary community-level efforts. Introduction Definition Water pollution is the contamination of natural water bodies by chemical, physical, radioactive or pathogenic microbial substances. Point sources of water pollution are described by the CWA as "any discernible, confined, and discrete conveyance from which pollutants are or may be discharged." These include pipes or man-made ditches from stationar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2008 DeerIsland BostonHarbor DocSearls 2452880753
8 (eight) is the natural number following 7 and preceding 9. In mathematics 8 is: * a composite number, its proper divisors being , , and . It is twice 4 or four times 2. * a power of two, being 2 (two cubed), and is the first number of the form , being an integer greater than 1. * the first number which is neither prime nor semiprime. * the base of the octal number system, which is mostly used with computers. In octal, one digit represents three bits. In modern computers, a byte is a grouping of eight bits, also called an octet. * a Fibonacci number, being plus . The next Fibonacci number is . 8 is the only positive Fibonacci number, aside from 1, that is a perfect cube. * the only nonzero perfect power that is one less than another perfect power, by Mihăilescu's Theorem. * the order of the smallest non-abelian group all of whose subgroups are normal. * the dimension of the octonions and is the highest possible dimension of a normed division algebra. * the first number ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turbidity
Turbidity is the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of water quality. Fluids can contain suspended solid matter consisting of particles of many different sizes. While some suspended material will be large enough and heavy enough to settle rapidly to the bottom of the container if a liquid sample is left to stand (the settable solids), very small particles will settle only very slowly or not at all if the sample is regularly agitated or the particles are colloidal. These small solid particles cause the liquid to appear turbid. Turbidity (or haze) is also applied to transparent solids such as glass or plastic. In plastic production, haze is defined as the percentage of light that is deflected more than 2.5° from the incoming light direction. Causes and effects Turbidity in open water may be caused by growth of phyto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combined Sewer Overflow
A combined sewer is a type of gravity sewer with a system of pipes, tunnels, pump stations etc. to transport sewage and urban runoff together to a sewage treatment plant or disposal site. This means that during rain events, the sewage gets diluted, resulting in higher flowrates at the treatment site. Uncontaminated stormwater simply dilutes sewage, but runoff may dissolve or suspend virtually anything it contacts on roofs, streets, and storage yards. As rainfall travels over roofs and the ground, it may pick up various contaminants including soil particles and other sediment, heavy metals, organic compounds, animal waste, and oil and grease. Combined sewers may also receive dry weather drainage from landscape irrigation, construction dewatering, and washing buildings and sidewalks. Combined sewers can cause serious water pollution problems during combined sewer overflow (CSO) events when combined sewage and surface runoff flows exceed the capacity of the sewage treatment plant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urban Runoff
Urban runoff is surface runoff of rainwater, landscape irrigation, and car washing created by urbanization. Impervious surfaces (roads, parking lots and sidewalks) are constructed during land development. During rain , storms and other precipitation events, these surfaces (built from materials such as asphalt and concrete), along with rooftops, carry polluted stormwater to storm drains, instead of allowing the water to percolate through soil. This causes lowering of the water table (because groundwater recharge is lessened) and flooding since the amount of water that remains on the surface is greater.Water Environment Federation Alexandria, VA; an American Society of Civil Engineers Reston, VA [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hazardous Waste
Hazardous waste is waste that has substantial or potential threats to public health or the environment. Hazardous waste is a type of dangerous goods. They usually have one or more of the following hazardous traits: ignitability, reactivity, corrosivity, toxicity. Listed hazardous wastes are materials specifically listed by regulatory authorities as hazardous wastes which are from non-specific sources, specific sources, or discarded chemical products. Hazardous wastes may be found in different physical states such as gaseous, liquids, or solids. A hazardous waste is a special type of waste because it cannot be disposed of by common means like other by-products of our everyday lives. Depending on the physical state of the waste, treatment and solidification processes might be required. The Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and Their Disposal was signed by 199 countries and went into force in 1992. Plastic was added to the convention i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Land Development
Land development is the alteration of landscape in any number of ways such as: * Changing landforms from a natural or semi-natural state for a purpose such as agriculture or housing * Subdividing real estate into lots, typically for the purpose of building homes * Real estate development or changing its purpose, for example by converting an unused factory complex into a condominium. Economic aspects In an economic context, land development is also sometimes advertised as land improvement or land amelioration. It refers to investment making land more usable by humans. For accounting purposes it refers to any variety of projects that increase the value of the process . Most are depreciable, but some land improvements are not able to be depreciated because a useful life cannot be determined. Home building and containment are two of the most common and the oldest types of development. In an urban context, land development furthermore includes: * Road construction ** Access ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as ''physical'' or ''mechanical'' erosion; this contrasts with ''chemical'' erosion, where soil or rock material is removed from an area by dissolution. Eroded sediment or solutes may be transported just a few millimetres, or for thousands of kilometres. Agents of erosion include rainfall; bedrock wear in rivers; coastal erosion by the sea and waves; glacial plucking, abrasion, and scour; areal flooding; wind abrasion; groundwater processes; and mass movement processes in steep landscapes like landslides and debris flows. The rates at which such processes act control how fast a surface is eroded. Typically, physical erosion procee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ohio
Ohio () is a state in the Midwestern region of the United States. Of the fifty U.S. states, it is the 34th-largest by area, and with a population of nearly 11.8 million, is the seventh-most populous and tenth-most densely populated. The state's capital and largest city is Columbus, with the Columbus metro area, Greater Cincinnati, and Greater Cleveland being the largest metropolitan areas. Ohio is bordered by Lake Erie to the north, Pennsylvania to the east, West Virginia to the southeast, Kentucky to the southwest, Indiana to the west, and Michigan to the northwest. Ohio is historically known as the "Buckeye State" after its Ohio buckeye trees, and Ohioans are also known as "Buckeyes". Its state flag is the only non-rectangular flag of all the U.S. states. Ohio takes its name from the Ohio River, which in turn originated from the Seneca word ''ohiːyo'', meaning "good river", "great river", or "large creek". The state arose from the lands west of the Appalachian Mountai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cuyahoga River
The Cuyahoga River ( , or ) is a river located in Northeast Ohio that bisects the City of Cleveland and feeds into Lake Erie. As Cleveland emerged as a major manufacturing center, the river became heavily affected by industrial pollution, so much so that it caught fire at least 14 times, most famously on June 22, 1969, helping to spur the American environmental movement. Since then, the river has been extensively cleaned up through the efforts of Cleveland's city government and the Ohio Environmental Protection Agency (OEPA). In 2019, the American Rivers conservation association named the Cuyahoga "River of the Year" in honor of "50 years of environmental resurgence". Etymology The name ''Cuyahoga'' is believed to mean "crooked river" from the Mohawk name ''Cayagaga'', although the Mohawk were never in the region alongside European settlers, so this explanation is questionable. Children in the area are usually taught that it comes from a Seneca word for "jawbone". This explan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fecal Coliform
A fecal coliform (British: faecal coliform) is a facultatively anaerobic, rod-shaped, gram-negative, non-sporulating bacterium. Coliform bacteria generally originate in the intestines of warm-blooded animals. Fecal coliforms are capable of growth in the presence of bile salts or similar surface agents, are oxidase negative, and produce acid and gas from lactose within 48 hours at 44 ± 0.5°C.Doyle, M. P., and M. C. Erickson. 2006"Closing the door on the fecal coliform assay."'' Microbe'' 1:162-163. . The term "thermotolerant coliform" is more correct and is gaining acceptance over "fecal coliform". Coliform bacteria include genera that originate in feces (e.g. ''Escherichia'') as well as genera not of fecal origin (e.g. ''Enterobacter'', ''Klebsiella'', '' Citrobacter''). The assay is intended to be an indicator of fecal contamination; more specifically of '' E. coli'' which is an indicator microorganism for other pathogens that may be present in feces. Presence of fecal co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkalinity
Alkalinity (from ar, القلوي, al-qaly, lit=ashes of the saltwort) is the capacity of water to resist acidification. It should not be confused with basicity, which is an absolute measurement on the pH scale. Alkalinity is the strength of a buffer solution composed of weak acids and their conjugate bases. It is measured by titrating the solution with an acid such as HCl until its pH changes abruptly, or it reaches a known endpoint where that happens. Alkalinity is expressed in units of concentration, such as meq/L (milliequivalents per liter), μeq/kg (microequivalents per kilogram), or mg/L CaCO3 (milligrams per liter of calcium carbonate). Each of these measurements corresponds to an amount of acid added as a titrant. Although alkalinity is primarily a term used by oceanographers, it is also used by hydrologists to describe temporary hardness. Moreover, measuring alkalinity is important in determining a stream's ability to neutralize acidic pollution from rainfall or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conductivity (electrolytic)
Conductivity (or specific conductance) of an electrolyte solution is a measure of its ability to conduct electricity. The SI unit of conductivity is Siemens per meter (S/m). Conductivity measurements are used routinely in many industrial and environmental applications as a fast, inexpensive and reliable way of measuring the ionic content in a solution. For example, the measurement of product conductivity is a typical way to monitor and continuously trend the performance of water purification systems. In many cases, conductivity is linked directly to the total dissolved solids (TDS). High quality deionized water has a conductivity of about 0.05 μS/cm at 25 °C, typical drinking water is in the range of 200–800 μS/cm, while sea water is about 50 mS/cm ncorrect according to source(or 50,000 μS/cm). Conductivity is traditionally determined by connecting the electrolyte in a Wheatstone bridge. Dilute solutions follow Kohlrausch's Laws of concentrat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
