Groundwater pollution: causes and consequences

Are many human activities that trigger pollution of groundwater . To know how groundwater contamination occurs, it is important to be clear about some processes such as infiltration and leachate of polluting substances since, for the most part, pollutants are incorporated into aquifers through filtration through the soil. Among the sources of contamination of aquifers or causes of contamination of groundwater we find the following:

• Industries are generators of multiple pollutants of chemical, organic or inorganic origin that can reach the environment through their discharge into blind wells, through leaks, spills, seepage from purification systems, etc.
• In agriculture, the diffuse contamination of groundwater by the use of chemical substances such as pesticides, fertilizers or herbicides stands out. Here we tell you more about chemical pollution: what it is, causes and consequences .
• On the other hand, urbanization and soil sealing affect the infiltration and purification functions of water, which with the expansion of urban centers means the destruction of the natural ecosystem and its biodiversity. These activities and their own domestic and individual unleash polluting processes through the atmospheric deposition of polluting particles, such as nitrogen, (from vehicle traffic , industrial emissions, livestock, urban discharges) and their subsequent leaching.
• Also septic systems, for the deposition and subsequent treatment of domestic wastewater, in case of failure, constitute a possible source of contamination of soil and groundwater .
• Following this line, the burial of garbage and radioactive waste stands out.
• Inadequate construction, abandonment of wells (illegal wells) and overexploitation of them. When collecting, it is possible that we contaminate a “healthy” aquifer by putting it in contact with another contaminated one or by breaking its water balance, thus allowing poor quality water to enter the reservoir.
• The injection of gray or polluted water into aquifers, to avoid spillage and surface contamination and also to achieve an improvement in the quality of the injected resource, is one more cause of this problem.

From all these water polluting actions, several types of groundwater contamination develop :

• Thermal (ex: nuclear power plant).
• Biological.
• By heavy metals .
• By organic matter.
• By nutrients.
• By acids.
• Radioactive.
• By xenobiotics.

Some of the effects of groundwater contamination are:

• Excessive concentration of nitrates in aquifers due to the excessive use of pesticides and fertilizers.
• Saline intrusion into aquifers by excessive pumping of groundwater in coastal areas. In this case, the cause is overexploitation of the resource itself.
• Presence of heavy metals (which induces diseases such as lead poisoning).
• Presence of xenobiotics and complex organic compounds that act as mutagens.

All this results in a decrease in the quality of these waters, which can affect the potability of the resource and, therefore, the consumption we make of it. To expand all this information, we encourage you to also read this other article on the Causes and consequences of water pollution .

Finally, we talk about the protection of groundwater against contamination and deterioration .

• Groundwater contamination is usually diagnosed late. To work on the early detection of these pollution processes, it is important to carry out a process of continuous monitoring and control through the river basin districts , in order to know the state of water quality .
• At the legislative level, concentration limits have been established for the presence of certain dangerous substances in the aquatic environment.
• However, regulatory efforts are a dead letter if individual, corporate and systemic or social will does not go ahead of all these measures. That is why, in addition to actions such as the installation of garbage dumps, dumps and industrial activities in impervious areas, the purification of water before its discharge into the natural environment, the monitoring of septic tanks , the removal of waste on the surface, of surface runoff, the injection of clean quality water …, environmental education plays a particularly relevant role . In this way, information and awareness become the most powerful tools to mitigate, reduce and correct groundwater pollution processes.

After having learned all this about the contamination of groundwater or contamination of aquifers, we recommend that you continue learning with these other AgroCorrn articles about Solutions to water pollution , How to avoid water pollution and How waters are formed underground .