A toxic chemical spill on one of our reservoir watersheds or intentional poisoning of our water supply would be front page news. The reaction from all kinds of government agencies would be swift. If intentional poisoning was suspected the Department of Homeland Security and the FBI would likely be part of the investigation.
Yet this same sort of thing happens to our groundwater supplies everyday and we seldom even know that it’s happening. While we do pay close attention to surface water recharge areas for our reservoirs, we seldom show the same respect or offer similar protection to our groundwater recharge areas. Though rock and soil perform as amazing natural filtering agents, like all filters they have their limitations. Not all perform equally well either.
Groundwater coming from the Tuscarora Sandstone of our mountainsides is of incredibly high quality. The Bellmeade Civic Association’s spring-fed water system on the eastern edge of Brush Mountain is testimony to that. Other springs along Brush Mountain have been found to contain fecal coliform bacteria, usually the result of animal waste.
Not all rocks in the region are effective filters, especially the sometimes cavernous limestones that allow water to flow more freely and quickly from the surface to the groundwater.
Nitrates and bacteria (from fertilizer and farm animal manures) can also find their way into groundwater. Ironically, this problem is most notable in agricultural valleys that owe their soil fertility to the limestone that helps build their productive soil and allow rapid movement of groundwater.
Groundwater pollutants are either chemical or biological and they behave differently. While things like chlorine or ultraviolet light can kill bacteria or filters can get rid of parasites, you cannot kill chemical pollutants since they are not living organisms. (Many folks think boiling water solves all ills, but it gets rid of only the biological contaminants.)
Pollutants can be naturally occurring or be introduced by man. Some, like sulfur or bacterial pollution, can be either.
The most important message, though, is that those man-made contaminants can easily be avoided. With a better understanding of how they get in the water and the exercising of a bit of common sense, the likelihood of groundwater contamination can be greatly reduced.
- Make sure your well is cased and grouted so that surface water does not flow directly into your well.
- Don’t spray or apply weed and feed products near your well head. If there is an herbicide in a product, it can find its way into groundwater. (Remember that broadleaf weeds like plantain and dandelion are discouraged by cutting your grass on a higher blade setting.)
- Don’t burn your trash. Beyond the unpleasantness of the odor, the ash from typical household waste contains very toxic residues, a few of which are potent cancer-causers. Remember that a large portion of the things that people burn can now be recycled.
- Be careful with automotive fluids and other petroleum-based chemicals. Never spread these on the ground. A small amount of used motor oil can do a great deal of damage to both surface waterways and groundwater.