Water bodies are important habitats for fish and other aquatic animals, and plants. Their management is important in ensuring that they remain available for the growth and sustenance of aquatic animals which should also be available for human and animal consumption.
Sources and Management of Groundwater Pollution
The other uses of the aquatic environment is to sustained them for future generations. The effect of pollution depends on the water body it impacts.
Pollution of running water, large river, or meals that are natural components of water may not show may show very little impact, or impacts may show where the water flows to.
Sources of Groundwater Pollution
Groundwater flows slowly beneath the earth’s surface in aquifers (porous geologic formations). Sources of groundwater pollution include:
1. Water-soluble pollutants (e.g. agricultural chemicals) and the quantity of pollutants reaching the groundwater depend on soil type, pollutant characteristics, and distance to the groundwater.
2. Runoff on soil surface percolates into groundwater with a portion of its pollutant load (e.g. nitrate in wastes from animal production operations).
3. Pathogens e.g. viruses, reach groundwater through sewage. Improperly treated septic systems can contaminate groundwater.
4. Improperly protected landfills can leach contaminants into groundwater including petrochemicals from leaking underground storage tanks.
5. Groundwater can contain detectable levels of pesticides. Management and pollution cleanup for groundwater is very difficult and expensive. It is better to prevent it.
Management of Groundwater Pollution or Contamination
1. Use pesticides with a low tendency to migrate into groundwater or apply very limited amounts to reduce runoff or leaching with rain.
2. Pump-and-treat: The groundwater is pumped to the surface, treated to remove pollutants, and returned to its source. This takes a long time and may produce little changes in water quality.
3. Building underground barrier to prevent contaminants from spreading off-site. This works only for shallow water that is contaminated in a way that it can be contained.
4. Groundwater can be treated in situ, e.g. by digging trenches, and installing tons of iron filings mixed with sand in the path of the groundwater.
5. Contaminated groundwater flows through it and some organic pollutants like trichloroethylene react with the iron to form benign products.
6. The use of anaerobic microorganisms to degrade the contaminants.