How do aquifers become polluted

Can cause slight increase in blood pressure in some adults. Probable carcinogen. Manganese Occurs naturally as a mineral from sediment and rocks or from mining and industrial waste.

Causes aesthetic and economic damage, and imparts brownish stains to laundry. Affects taste of water, and causes dark brown or black stains on plumbing fixtures. Relatively non-toxic to animals but toxic to plants at high levels.

Mercury Occurs as an inorganic salt and as organic mercury compounds. Enters the environment from industrial waste, mining, pesticides, coal, electrical equipment batteries, lamps, switches , smelting, and fossil-fuel combustion.

Causes acute and chronic toxicity. Targets the kidneys and can cause nervous system disorders. Nickel Occurs naturally in soils, groundwater, and surface water. Often used in electroplating, stainless steel and alloy products, mining, and refining. Damages the heart and liver of laboratory animals exposed to large amounts over their lifetime.

Nitrate as nitrogen Occurs naturally in mineral deposits, soils, seawater, freshwater systems, the atmosphere, and biota. More stable form of combined nitrogen in oxygenated water. Found in the highest levels in groundwater under extensively developed areas. Enters the environment from fertilizer, feedlots, and sewage. Toxicity results from the body's natural breakdown of nitrate to nitrite. Causes "bluebaby disease," or methemoglobinemia, which threatens oxygen-carrying capacity of the blood.

Selenium Enters environment from naturally occurring geologic sources, sulfur, and coal. Causes acute and chronic toxic effects in animals--"blind staggers" in cattle. Nutritionally essential element at low doses but toxic at high doses. Silver Enters environment from ore mining and processing, product fabrication, and disposal.

Often used in photography, electric and electronic equipment, sterling and electroplating, alloy, and solder. Because of great economic value of silver, recovery practices are typically used to minimize loss.

Can cause argyria, a blue-gray coloration of the skin, mucous membranes, eyes, and organs in humans and animals with chronic exposure. Sodium Derived geologically from leaching of surface and underground deposits of salt and decomposition of various minerals.

Human activities contribute through de-icing and washing products. Can be a health risk factor for those individuals on a low-sodium diet. Sulfate Elevated concentrations may result from saltwater intrusion, mineral dissolution, and domestic or industrial waste.

Forms hard scales on boilers and heat exchangers; can change the taste of water, and has a laxative effect in high doses. Thallium Enters environment from soils; used in electronics, pharmaceuticals manufacturing, glass, and alloys. Damages kidneys, liver, brain, and intestines in laboratory animals when given in high doses over their lifetime.

Zinc Found naturally in water, most frequently in areas where it is mined. Enters environment from industrial waste, metal plating, and plumbing, and is a major component of sludge. Aids in the healing of wounds. Causes no ill health effects except in very high doses. Imparts an undesirable taste to water. Toxic to plants at high levels.

Organic contaminants found in groundwater Contaminant Sources to groundwater Potential health and other effects Volatile organic compounds Enter environment when used to make plastics, dyes, rubbers, polishes, solvents, crude oil, insecticides, inks, varnishes, paints, disinfectants, gasoline products, pharmaceuticals, preservatives, spot removers, paint removers, degreasers, and many more.

Can cause cancer and liver damage, anemia, gastrointestinal disorder, skin irritation, blurred vision, exhaustion, weight loss, damage to the nervous system, and respiratory tract irritation. Pesticides Enter environment as herbicides, insecticides, fungicides, rodenticides, and algicides. Cause poisoning, headaches, dizziness, gastrointestinal disturbance, numbness, weakness, and cancer.

Destroys nervous system, thyroid, reproductive system, liver, and kidneys. Plasticizers, chlorinated solvents, benzo[a]pyrene, and dioxin Used as sealants, linings, solvents, pesticides, plasticizers, components of gasoline, disinfectant, and wood preservative. Enters the environment from improper waste disposal, leaching runoff, leaking storage tank, and industrial runoff.

Cause cancer. Damages nervous and reproductive systems, kidney, stomach, and liver. Microbiological contaminants found in groundwater Contaminant Sources to groundwater Potential health and other effects Coliform bacteria Occur naturally in the environment from soils and plants and in the intestines of humans and other warm-blooded animals.

Used as an indicator for the presence of pathogenic bacteria, viruses, and parasites from domestic sewage, animal waste, or plant or soil material. Bacteria, viruses, and parasites can cause polio, cholera, typhoid fever, dysentery, and infectious hepatitis. Physical characteristics of groundwater Contaminant Sources to groundwater Potential health and other effects Turbidity Caused by the presence of suspended matter such as clay, silt, and fine particles of organic and inorganic matter, plankton, and other microscopic organisms.

A measure how much light can filter through the water sample. Objectionable for aesthetic reasons. Indicative of clay or other inert suspended particles in drinking water.

May not adversely affect health but may cause need for additional treatment. Following rainfall, variations in groundwater turbidity may be an indicator of surface contamination.

Color Can be caused by decaying leaves, plants, organic matter, copper, iron, and manganese, which may be objectionable. Indicative of large amounts of organic chemicals, inadequate treatment, and high disinfection demand. Potential for production of excess amounts of disinfection byproducts. Suggests that treatment is needed. No health concerns. Aesthetically unpleasing. Represented on a scale of where 0 is the most acidic, 14 is the most alkaline, and 7 is neutral.

High pH causes a bitter taste; water pipes and water-using appliances become encrusted; depresses the effectiveness of the disinfection of chlorine, thereby causing the need for additional chlorine when pH is high. Low-pH water will corrode or dissolve metals and other substances. Odor Certain odors may be indicative of organic or non-organic contaminants that originate from municipal or industrial waste discharges or from natural sources.

Taste Some substances such as certain organic salts produce a taste without an odor and can be evaluated by a taste test. Many other sensations ascribed to the sense of taste actually are odors, even though the sensation is not noticed until the material is taken into the mouth.

Below are other science projects associated with groundwater contamination. Date published: October 9, Filter Total Items: 7. Road salt, toxic substances from mining sites, and used motor oil also may seep into groundwater. In addition, it is possible for untreated waste from septic tanks and toxic chemicals from underground storage tanks and leaky landfills to contaminate groundwater.

Drinking contaminated groundwater can have serious health effects. Diseases such as hepatitis and dysentery may be caused by contamination from septic tank waste. Poisoning may be caused by toxins that have leached into well water supplies. Wildlife can also be harmed by contaminated groundwater. Other long term effects such as certain types of cancer may also result from exposure to polluted water. May contain gasoline, oil, chemicals, or other types of liquids and they can either be above or below ground.

There are estimated to be over 10 million storage tanks buried in the United States and over time the tanks can corrode, crack and develop leaks. If the contaminants leak out and get into the groundwater, serious contamination can occur.

Onsite wastewater disposal systems used by homes, offices or other buildings that are not connected to a city sewer system. Septic systems are designed to slowly drain away human waste underground at a slow, harmless rate.

Even more concerning is the fact that overwhelmed and aging sewage treatment systems are becoming less effective over time, and are currently releasing over billion gallons of untreated wastewater each year. According to the U. Environmental Protection Agency, in alone, the United States produced Where did all of it go? More than half of it was deposited in landfills.

Landfills are normally designed to protect against contaminant leakage. Complex systems of liners and protective layers are put down before dumping to prevent contaminants from seeping into the ground and contaminating natural resources. In rare cases, toxic leachate from the landfill can seep through cracks or holes in the landfill lining and reach groundwater.

More often, however, contamination occurs through more indirect means. The most common landfill-associated contamination occurs through transportation, runoff and animal activity. Waste-carrying trucks leak solid and hazardous waste as they transport materials, or get into accidents that result in leaks.

The rain that flows through the landfill is another source of pollution, as it is rarely treated before being dumped back into the surrounding environment.

Finally, bird populations often feed on new trash added to landfills, then fly to secondary locations, carrying with them any toxins they picked up while they were at the landfill. Since groundwater is part of the water cycle, contaminants affecting other parts of the cycle can have a significant effect on groundwater quality. As a primary example, air pollution can be picked up by the water in the atmosphere to produce acid rain, which is a grave problem for groundwater supplies.

As a result, when the acid rain hits the ground, it can seep in and affect groundwater. Many plants and animals are sensitive to acids and may experience increased mortality in the presence of acid rain, negatively affecting the ecosystem in general and causing long-lasting effects. Acid rain is even dangerous to humans, as it can cause skin and lung irritation, and prolonged exposure can cause heart problems. Fuels are another source of contamination that can get into groundwater sources through several means.

One common way that fuel negatively affects groundwater sources is through air contamination. When cars, ships, airplanes, coal-fired power plants and industrial operations burn fossil fuels, they release nitrogen oxides into the air , which contribute to the production of acid rain.

The acid rain then deposits these nitrogen oxides back onto land, washing it into nearby water bodies and into groundwater sources. Another common cause of fuel pollution is stormwater runoff. Cars and planes may leak fuel as they operate, or fuel may spill during the fueling process.

Storms may then wash any gas or other fluids left on the road into wastewater systems. Because the majority of wastewater is untreated, this fuel pollution will likely leak into the environment. Finally, petroleum byproducts may get into the surrounding environment through factory runoff or petroleum drilling practices.

Petroleum has to go through extensive processing to create final products like gasoline and petroleum-based chemicals. While municipal sewage systems serve 80 percent of American homes and businesses , about 20 percent are responsible for their own waste management.

Septic systems are onsite wastewater disposal systems commonly used by homes and offices. While properly built septic systems are designed to drain human waste at a harmless rate, poor design, location, maintenance, or construction can cause these systems to leak pathogens, household chemicals, and other contaminants into the surrounding area.

This issue can be particularly problematic for people who get their drinking water from nearby private wells. Chemical contaminants come from a variety of residential, agricultural and industrial sources. Aluminum, Chloramine, Lead, Mercury, Radium, and Uranium are just a few examples of common waterborne chemical contaminants.

Runoff from industrial and agricultural areas is one of the most common ways that these chemicals get into groundwater. However, current estimates state that there are about 20, known abandoned and uncontrolled hazardous waste sites in the United States, and that number increases with each passing year. These waste sites are dangerous, as any leaks in containment vessels can cause hazardous materials to leak into the soil and groundwater.