Groundwater Pollution: Human Activity's Impact And Solutions

Groundwater pollution is a serious issue, and while human activity is a major contributor, there are also natural processes that can cause it. For example, some rocks contain toxic metals such as mercury and arsenic, which can dissolve in water and make it lethal. This is an example of groundwater pollution that is not caused by humans.

Arsenic and mercury in rocks

Arsenic is a naturally occurring metalloid that is found in the Earth's crust. It is often found in rocks and minerals, as well as in soil and water. Arsenic can be released into the environment through natural processes such as weathering and erosion, or through human activities such as mining and industrial processes.

Mercury is also a naturally occurring element that is found in the Earth's crust. It is often found in rocks and minerals, as well as in soil and water. Mercury can be released into the environment through natural processes such as volcanic eruptions and forest fires, or through human activities such as coal burning and gold mining.

Both arsenic and mercury can contaminate groundwater when they are released into the environment. Groundwater is water that is found underground in aquifers, which are large natural reservoirs or sources of water below the surface of the Earth. When arsenic and mercury are dissolved in water, they can make their way into aquifers and contaminate the groundwater.

The presence of arsenic and mercury in rocks can be a significant source of groundwater pollution, especially in areas where these toxic metals are naturally occurring. While human activities such as mining and industrial processes can also release arsenic and mercury into the environment, the natural occurrence of these metals in rocks is a reminder that not all groundwater pollution is human-caused.

Natural processes

Other naturally-occurring substances, such as decaying organic matter, can move in groundwater as particles. Some of these contaminants may accumulate in excess quantities, posing a health threat if consumed. Others may produce an unpleasant odour, taste, or colour. Groundwater containing these materials needs to be treated before it is used for domestic uses.

Saline ingress following over drafting of aquifers or natural leaching from naturally occurring deposits are also natural sources of groundwater pollution. Groundwater pollution can also occur from on-site sanitation systems, landfill leachate, effluent from wastewater treatment plants, leaking sewers, petrol filling stations, and hydraulic fracturing (fracking).

Aquifer pollution

The contamination of aquifers can be caused by a variety of human activities, including agricultural practices and the discharge of used waters into water bodies. Monitoring aquifer pollution is an important strategy in managing groundwater quality. However, even where aquifer protection policies exist, monitoring is often inadequate to detect pollution incidents.

One approach to managing aquifer pollution is managed aquifer recharge (MAR), where treated surface water is infiltrated and left to percolate in the ground, eventually contributing to groundwater recharge. This helps to balance groundwater recharge and abstraction.

Groundwater pollution is a worldwide issue, with a study of the groundwater quality of the principal aquifers of the United States showing that 23% of domestic wells had contaminants at levels greater than human-health benchmarks. Another study identified the major groundwater pollution problems in Africa as nitrate pollution, pathogenic agents, organic pollution, salinization, and acid mine drainage.

Water toxicity

The proliferation of heavy metal ions in water bodies has become a significant global concern due to the detrimental effects on the environment and living organisms. These toxic metals can accumulate in the bodies of animals and humans, leading to serious health issues. For example, they can interfere with the normal functioning of structural proteins, enzymes, and nucleic acids, affecting the immune and hematopoietic systems.

To protect human health, regulatory bodies such as the EPA have set limits on the amounts of heavy metals permissible in drinking water. Regular testing of water sources is necessary to ensure that they remain safe from contamination and to safeguard public health.

The increase in industrialization and urbanization has led to a rise in the levels of toxic heavy metals in water sources. As the world's population continues to grow, so does the demand for development and industrialization, further contributing to water contamination.

Lethal water pollution

Groundwater contamination can be lethal. Over 50% of the United States population depends on groundwater for drinking water, and nearly 40% of Americans rely on groundwater for their drinking water. Groundwater is also one of our most important sources of water for irrigation.

Groundwater contamination occurs when man-made products such as gasoline, oil, road salts, and chemicals get into the groundwater and cause it to become unsafe and unfit for human use. Materials from the land’s surface can move through the soil and end up in the groundwater. For example, pesticides and fertilizers can find their way into groundwater supplies over time. Road salt, toxic substances from mining sites, and used motor oil also may seep into groundwater.

Human activities carried out on the surface, such as sewage disposal and the overuse of pesticides and fertilizers, including animal manure, are among the main sources of contamination and pollution of groundwater. Industrial discharges, urban activities, agriculture, groundwater pumpage, and disposal of waste can also affect groundwater quality. Contaminants can be human-induced, as from leaking fuel tanks or toxic chemical spills.

Many studies have shown that high levels of fluoride, nitrate, metals, and persistent organic pollutants are a health risk for human populations. This is especially critical for infants and children who are more susceptible to the effects of these contaminants than adults. For example, “blue baby syndrome,” also known as infant methemoglobinemia, is caused by excessive nitrate concentrations in the drinking water used to make baby formulas.

Frequently asked questions