Ground water is said to be water that comes from rain, hail, snow or sleet and soaks into the ground. The water is pushed by gravity to the ground and passes through particles of soil, sand, rock and gravel until it reaches a level where the ground is saturated with water. Ground area that is saturated with water is called saturated zone and the top level of this zone is called water table. Water table may be very near the ground surface or some thousands of feet below.
Half of the population in United States uses ground water for domestic purposes, irrigation and in industries. Groundwater is usually clean but sometimes it can be polluted or contaminated by human beings. The water is contaminated by pollutants that have been dumped on the ground such as fertilizer, pesticides or leaky underground tanks used to store gasoline and leaky landfills (Tobin, 4). Ground water pollution is therefore defined as unwanted change in the quality of groundwater due to human activities.
Ground water contains mineral ions which dissolve from rocks, soil particles and sediments as the water travels along pores of mineral surfaces. The pollutants inform of mineral ions are known as dissolved solids which is classified into major constituents, minor constituents and trace elements. The dissolved solids in water are either positively or negatively charged ions known as cations and anions respectively. Total negative charge of the anions is always equal to total positive charge of cations (Laws, 21). The naturally occurring dissolved solids constitute of inorganic constituents such as minerals, nutrients and trace metals. The trace elements are usually low to a level that cannot harm human health. In Europe, groundwater from springs and wells is considered to have trace elements that are essential for human metabolism which is a remedy for certain ailments.
Activities by human beings can alter the natural composition of ground water through disposal of chemicals into soils, land surface or through direct injection of wastes into ground water. A ground water pollutant is said to be any substance that when it reaches the aquifer, it makes water unclean for a particular purpose. Manufactured chemicals are considered as major pollutants of groundwater.
Sediment and soil layers deposited above an aquifer acts as natural filter that keeps inorganic pollutants from infiltrating to groundwater. However, the effectiveness of the soil layers has declined over the past decades and has resulted to a significant amount of groundwater contamination. This has made prevention of groundwater contamination almost impossible. Groundwater contamination caused by human activities is usually categorized into point source and non-point source pollution. Point source pollution is contamination of ground water pollution that originates from single tank, disposal site or facility (Hunter, Waterman, 12). Examples of point source include waste from industries, dump sites, accidental spills and leaking gasoline storage tanks.
On the other hand, non-point source pollution include pollutants that are spread across a wide area such chemicals used in agriculture like pesticides, fertilizers and herbicides. Non point source substances have a larger impact on the quality of ground water than any other form of pollutant. Ground water pollution can occur from natural substances such as toxic metal arsenic which is found in many rocks of Western United States. The concentration of toxic metal arsenic in groundwater can exceed the expected level thus making the water unclean for drinking.
Petroleum based fuels such as diesel or gasoline is another common pollutant of groundwater in United States. U.S Environmental Protection Agency has confirmed leakages of underground petroleum-based storage fuel tanks as a major threat to ground water. Petroleum fuels consist of hydrocarbons that dissolve in water and thus result to health hazard in humans who use the water. Most waste disposal from industries constitutes of petroleum products and this has been a threat to ground water. In developed nations, laws have been established to prevent land and water pollution (Tobin, 7). Developing nations have a risk of ground water contamination that results from massive use of land and economic distress.
Chlorinated solvents are another class of ground water contamination and a good example of such chemical is perchloroethylene. Chemicals in chlorinated substances are similar to petroleum based fuels but the presence of chlorine is an exceptional case. The presence of chlorine in chlorinated solvents makes this class of pollutants more toxic than fuels. Chlorine contaminated aquifers are more difficult to clean up than those that have been contaminated by fuels. Various pollutants of ground water are very dangerous to the health of human beings and thorough cleaning of contaminated water should be done by environmentalists (Laws, 19).
Cleaning of contaminated groundwater
Ground water is contaminated when rain water soaks into ground, picks up chemicals, and comes into contact with buried waste and other contaminants. Ground water moves slowly and with little dilution, turbulence or mixing the contaminants form concentrated plume once they settle between pores of sediment. Clean up laws is one of the major techniques that can be used to clean up contaminated water. Federal laws in the United States aims at preventing contamination of groundwater from industrial or commercial pollutants (Hunter, Waterman, 31). The laws give citizens the power to sue industries or factories that violate the laws through pollution of groundwater.
Several steps are followed to clean up a site once contamination has been detected. The first step is to carry out an investigation so as to determine the nature and level of contamination. A second step is to do a risk assessment so as to establish whether the contamination can harm human health. Once the assessment has been done, the next step is to evaluate various methods that can be used during the feasibility study. A cost effective and most feasible clean up alternative is chosen during the remedial design phase.
Cleaning of contaminated groundwater is done for several purposes first objective is to contain the contaminants so as to prevent further migration. This ensures stoppage of further flow of contaminants into ground water. A second objective is to remove all contaminants from the aquifer which helps to clean up water. A third purpose of cleaning up groundwater is to remediate the aquifer by detoxifying contaminants at their initial state.
Fourth aim is to treat groundwater at its point of use and abandoning the aquifer so as to find an alternative source of water. Containment of ground water pollution is the best method of preventing pollution. The best technique is the use of reactive substances that detoxify the contaminants. Another alternative is the use of underground barrier of clay, steel or cement (Laws, 44). The use of groundwater extraction wells is the best common method used to a full range of contaminants.
Contamination of groundwater is risky to human health and every individual has the mandate to take appropriate measures so as to reduce environmental pollution. Laws should be enforced to ensure that violators are charged for their ignorance.
Half of the population in United States uses ground water for domestic purposes, irrigation and in industries. Groundwater is usually clean but sometimes it can be polluted or contaminated by human beings. The water is contaminated by pollutants that have been dumped on the ground such as fertilizer, pesticides or leaky underground tanks used to store gasoline and leaky landfills (Tobin, 4). Ground water pollution is therefore defined as unwanted change in the quality of groundwater due to human activities.
Ground water contains mineral ions which dissolve from rocks, soil particles and sediments as the water travels along pores of mineral surfaces. The pollutants inform of mineral ions are known as dissolved solids which is classified into major constituents, minor constituents and trace elements. The dissolved solids in water are either positively or negatively charged ions known as cations and anions respectively. Total negative charge of the anions is always equal to total positive charge of cations (Laws, 21). The naturally occurring dissolved solids constitute of inorganic constituents such as minerals, nutrients and trace metals. The trace elements are usually low to a level that cannot harm human health. In Europe, groundwater from springs and wells is considered to have trace elements that are essential for human metabolism which is a remedy for certain ailments.
Activities by human beings can alter the natural composition of ground water through disposal of chemicals into soils, land surface or through direct injection of wastes into ground water. A ground water pollutant is said to be any substance that when it reaches the aquifer, it makes water unclean for a particular purpose. Manufactured chemicals are considered as major pollutants of groundwater.
Sediment and soil layers deposited above an aquifer acts as natural filter that keeps inorganic pollutants from infiltrating to groundwater. However, the effectiveness of the soil layers has declined over the past decades and has resulted to a significant amount of groundwater contamination. This has made prevention of groundwater contamination almost impossible. Groundwater contamination caused by human activities is usually categorized into point source and non-point source pollution. Point source pollution is contamination of ground water pollution that originates from single tank, disposal site or facility (Hunter, Waterman, 12). Examples of point source include waste from industries, dump sites, accidental spills and leaking gasoline storage tanks.
On the other hand, non-point source pollution include pollutants that are spread across a wide area such chemicals used in agriculture like pesticides, fertilizers and herbicides. Non point source substances have a larger impact on the quality of ground water than any other form of pollutant. Ground water pollution can occur from natural substances such as toxic metal arsenic which is found in many rocks of Western United States. The concentration of toxic metal arsenic in groundwater can exceed the expected level thus making the water unclean for drinking.
Petroleum based fuels such as diesel or gasoline is another common pollutant of groundwater in United States. U.S Environmental Protection Agency has confirmed leakages of underground petroleum-based storage fuel tanks as a major threat to ground water. Petroleum fuels consist of hydrocarbons that dissolve in water and thus result to health hazard in humans who use the water. Most waste disposal from industries constitutes of petroleum products and this has been a threat to ground water. In developed nations, laws have been established to prevent land and water pollution (Tobin, 7). Developing nations have a risk of ground water contamination that results from massive use of land and economic distress.
Chlorinated solvents are another class of ground water contamination and a good example of such chemical is perchloroethylene. Chemicals in chlorinated substances are similar to petroleum based fuels but the presence of chlorine is an exceptional case. The presence of chlorine in chlorinated solvents makes this class of pollutants more toxic than fuels. Chlorine contaminated aquifers are more difficult to clean up than those that have been contaminated by fuels. Various pollutants of ground water are very dangerous to the health of human beings and thorough cleaning of contaminated water should be done by environmentalists (Laws, 19).
Cleaning of contaminated groundwater
Ground water is contaminated when rain water soaks into ground, picks up chemicals, and comes into contact with buried waste and other contaminants. Ground water moves slowly and with little dilution, turbulence or mixing the contaminants form concentrated plume once they settle between pores of sediment. Clean up laws is one of the major techniques that can be used to clean up contaminated water. Federal laws in the United States aims at preventing contamination of groundwater from industrial or commercial pollutants (Hunter, Waterman, 31). The laws give citizens the power to sue industries or factories that violate the laws through pollution of groundwater.
Several steps are followed to clean up a site once contamination has been detected. The first step is to carry out an investigation so as to determine the nature and level of contamination. A second step is to do a risk assessment so as to establish whether the contamination can harm human health. Once the assessment has been done, the next step is to evaluate various methods that can be used during the feasibility study. A cost effective and most feasible clean up alternative is chosen during the remedial design phase.
Cleaning of contaminated groundwater is done for several purposes first objective is to contain the contaminants so as to prevent further migration. This ensures stoppage of further flow of contaminants into ground water. A second objective is to remove all contaminants from the aquifer which helps to clean up water. A third purpose of cleaning up groundwater is to remediate the aquifer by detoxifying contaminants at their initial state.
Fourth aim is to treat groundwater at its point of use and abandoning the aquifer so as to find an alternative source of water. Containment of ground water pollution is the best method of preventing pollution. The best technique is the use of reactive substances that detoxify the contaminants. Another alternative is the use of underground barrier of clay, steel or cement (Laws, 44). The use of groundwater extraction wells is the best common method used to a full range of contaminants.
Contamination of groundwater is risky to human health and every individual has the mandate to take appropriate measures so as to reduce environmental pollution. Laws should be enforced to ensure that violators are charged for their ignorance.
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