Groundwater is a hidden resource that exists underground, flowing through the cracks and spaces between rocks and soil in aquifers. Though out of sight, its importance cannot be underestimated - it is the largest source of freshwater on the planet, providing drinking water to over half of the world's population. 

Yet this vital resource is at growing risk. Human activities are introducing toxic chemicals that seep into aquifers, silently poisoning the groundwater. Heavy metals and industrial pollutants have been linked to severe health issues once people are exposed. What's more, groundwater contamination can persist for generations as pollutants spread. 

With treatment of contaminated groundwater being costly, prevention is key. In this article, we will learn about the lasting effects of groundwater pollution.

What Is Groundwater, Anyway?

Groundwater plays an important role in meeting global water needs. It is estimated that groundwater provides about half of all drinking water worldwide, around 40% of agricultural water usage, and approximately 30% of water required for industry. 

Beyond direct human uses, groundwater also sustains aquatic ecosystems, maintains river flows between rain events, and prevents issues like land subsidence and saltwater intrusion into freshwater sources.

As climate change introduces more uncertainty, there is a need to improve our understanding of groundwater systems, strengthen management practices, and implement adaptive strategies that consider both groundwater and surface water together.

Groundwater refers to the water found underground in the pore spaces and fractures within soil, sand, and rock formations. It is stored in and gradually travels through subsurface geological structures called aquifers. Aquifers are made up of layers of permeable materials like silt, sand, gravel, or fractured bedrock that have the ability to hold and transmit groundwater in usable quantities.

Causes of Groundwater Contamination

There are various causes of groundwater contamination, both natural and human-induced. While natural processes can introduce substances like minerals, the majority of contamination is due to human activity. The top six anthropogenic sources are outlined below.

Improper septic system design and maintenance is a primary reason for groundwater pollution in the US. When not functioning correctly, septic systems can leak bacteria, viruses, nitrates, and other contaminants into underground sources.

Hazardous materials disposal is another major issue. Paint thinners, pool chemicals, and gasoline should never be put in regular landfills as they can leach into soil and pollute aquifers. Contact your local waste management for safe hazardous waste drop-off.

Underground storage tanks used for gasoline, heating oil, and chemicals are widespread, especially for highway departments. As these corrode over time, leaks contaminate surrounding earth and groundwater supplies.

Mining waste often contains heavy metals and sulfides that leach into water supplies during rainfall.

Pesticides and fertilizers applied extensively on farms, lawns, and golf courses accumulate and migrate downward, threatening wells, especially in agricultural regions. Nitrates and VOCs from these sources pose risks to the quality of drinking water.

Health Risks Caused By Groundwater Contamination

Groundwater contamination poses significant threats to public health, manifesting in outbreaks linked to untreated water or deficiencies in water treatment facilities. These incidents often involve the proliferation of pathogens such as Shigella, Hepatitis A, norovirus, Giardia, Campylobacter, Salmonella, Cryptosporidium (a parasite), E. coli (a bacterium), and various viruses. 

The repercussions of these contaminants extend to health issues like diarrhea, reproductive complications, and disorders of the nervous system. Infants, young children, pregnant women, the elderly, and immunocompromised individuals are particularly vulnerable.

An illustrative case highlighting the severe health consequences of groundwater contamination is the episode at Camp Lejeune in North Carolina. According to TorHoerman Law, residents of the Marine Corps base between 1953 and 1987 faced potential exposure to polluted drinking water, significantly elevating their risks of cancer and other diseases. 

Acknowledging the correlation between Camp Lejeune's toxic water supply and specific medical conditions, the U.S. government has grappled with the aftermath. In the 1980s, a private well supplying the base was found contaminated with trichloroethylene (TCE), a chemical used in dry cleaning and metal degreasing. 

Although the well was eventually closed, a considerable number of individuals had already consumed the contaminated water. Subsequent investigations revealed the presence of additional toxic chemicals like benzene and vinyl chloride, recognized for their role in causing cancer, birth defects, and liver damage.

In response to the Camp Lejeune water contamination crisis, victims are pursuing claims against the federal government, with adjudication conducted by the Navy JAG within a six-month timeframe. 

The enactment of the Camp Lejeune Justice Act provides much-needed relief for those exposed to the toxic water supply at the base. Although the exact settlement amounts remain unspecified at present, projections anticipate the payout for Camp Lejeune lawsuits reaching up to $6.1 billion. This underscores the magnitude of concern surrounding groundwater contamination and emphasizes the imperative to address its far-reaching implications.

Measures You Can Take to Reduce Groundwater Contamination

There are several measures individuals and communities can take to mitigate its impact:

Using the Precautionary Principle

The precautionary principle guides that anticipatory action should be taken to prevent harm, even if the scientific evidence is not conclusive about the potential harm. This principle promotes the idea of taking preventative measures to protect the environment from damage rather than waiting for absolute certainty about risks.

Monitoring the Quality of Groundwater Through a Telemetry System

Monitoring groundwater quality helps identify potential issues and allows for timely response. Industries that rely on groundwater resources should regularly measure parameters like pH, flow rate, total suspended solids, and water level. This testing can reveal changes that require investigation or remediation before extensive pollution occurs. Prompt action when problems are detected helps minimize environmental impact.

Land Zoning or Marking

Zoning and delineation of land uses near groundwater sources provide focused protection. By designating areas suitable for specific purposes, vulnerable aquifers and recharge locations receive elevated safeguards. Mapping techniques allocate zones for activities like agriculture, industry, and development based on subsurface geology and other risk factors.

 Two common types are aquifer vulnerability maps and source protection maps. Together with regular monitoring, zoning strategies help prevent groundwater degradation from hazardous contaminants at the earliest possible stage. 

Via Statuary Regulations

Government regulations have an important role to play in addressing groundwater pollution. In India, the Central Groundwater Authority (CGWA) is responsible for overseeing groundwater resources nationwide as per the Environmental Protection Act. 

CGWA's guidelines mandate that certain high-impact industries install groundwater monitoring telemetry systems. These industries must report findings to CGWA to facilitate oversight. Strict regulations and monitoring aim to prevent uncontrolled contamination.

Educating Others

Raising public awareness about protecting groundwater is also key to tackling this issue. Groundwater supports communities and agriculture. As a shared resource essential to meeting current and future needs, its preservation requires participation from all. Individual actions, no matter how small, contribute to the overall effort when widely adopted.

Education empowers people to make informed choices that reduce impacts. Awareness of groundwater's vulnerability and our dependence on its clean supply motivates collective responsibility for the long-term sustainability of this vital underground asset. 

In conclusion, groundwater contamination poses significant threats to public health. It requires concerted prevention efforts through various measures, like prudent regulations, monitoring, education, and applying the precautionary principle to mitigate risks to this critical resource.