When it comes to earth repair and grassroots bioremediation, knowing what sort of contamination you are working with allows you to engage in the appropriate clean-up techniques, as well as properly protect yourself and the folks in your community.
Also, when looking to clean-up a site, we have to ask ourselves whether we are dealing with metals, chemicals, or both. If you are dealing with heavy metals, remember that they can be bound and extracted, but not broken down. When dealing with chemicals, remember that unlike metals, they can be broken down.
Below is a list of some of the common contaminants you may find on your site. There are many contaminants not listed here that may be present in the environments you are working with, but this is a good place to start.