Four Things to Consider If Developing Land in an Area With Contaminated Groundwater
If you are developing a building site and you are worried that the area is contaminated, you may want to check out the EPA's records on contaminated sites. In particular, if the water table is contaminated, there are several things you need to keep in mind as you develop your site.
1. Don't Use Standard-Depth Bores
Water bores can be a useful way to provide water to the residents of the area you are developing, but if the groundwater is contaminated, this option doesn't work. In most cases, domestic bores draw water from relatively shallow parts of the aquifer. If the groundwater is contaminated, the water from these sources will be contaminated as well — these shallow aquifers tend to have chemical and biological contaminants, simply because they aren't protected by layers of bedrock.
2. Consider Deeper Bores
In some cases, you may be able to put in bores that go more deeply into the bedrock, and these bores can sometimes access water that is safe to consume. You may want to consult with the local environmental authorities in your area to see if a deeper bore may work. Alternatively, you may want to hire a consultant to do an environmental assessment so you can identify a safe depth for your bore.
3. Don't Use Shallow Bores for Non Potable Water
In some cases, developers or homeowners think it's okay to use shallow bores in contaminated areas if they only use the water for nonpotable purposes. You should not do this. Even if the water is only used for irrigation or flushing toilets, it gets introduced into the water cycle, and even if it eventually goes through a sanitation plant, many of the contaminants will linger. Because of that, you need to keep that contaminated water where it is.
4. Investigate the Need for a Barrier
In some cases, just leaving the groundwater alone is enough, but in other cases, there may be a risk of toxic vapors seeping up from underground. Talk with an environmental assessment expert to see if there is a risk of toxic vapors, and make sure that the excavation strategies you plan to use don't risk upsetting toxins. If necessary, you may want to explore the benefits of putting a vapor barrier somewhere between the bedrock and the top soil.
To learn more about developing in a contaminated area, contact a consultant to talk about options and strategies today.