Soil can be contaminated by any of a number of ways, rendering the land it occupies unsuitable for crops and livestock, illegal to develop, and potentially toxic to the human environment. Soil testing represents the key first and last steps of any cleanup operation.
Depending on the levels and type of toxicity, a cleanup operation can involve relatively inexpensive remediation methods, such as simply rezoning and sealing affected land, or the introduction of suitable microbial agents into the soil to digest certain chemicals at one end of the scale, and at the other, total excavation and containment of affected topsoil, such as has been conducted in retired nuclear testing sites in the deserts of Australia and China.
Before redeveloping any land after a significant period, you should consider contracting the services offered by leading soil testing company, Midwest Laboratories, in order to ascertain the presence or absence of any potentially harmful agents.
Contaminated soil testing will reveal the presence of several types of contaminants, such as volatile compounds like acetone, benzene, chloroform, trichloroethylene, tetrachloroethylene, and toluene; other organic compounds like oils and petroleum products, PCBs, and gasoline additives; heavy metals such as arsenic, cadmium, lead, and mercury, and other toxic substances like barium and hydrogen cyanide.
Other substances that are not strictly considered pollutants may also be found at excessive concentrations, like fertilizers, pesticides, and their metabolites. When found in sufficiently high concentrations, these can act as pollutants by changing the pH of the soil, reacting with nutrients, or rendering the ones present less readily available to plants.
A comprehensive soil test from Midwest Labs will not only show which toxins are present, but with professional interpretation of the results, can also be used to predict what cleanup methods will be most effective. This will depend on various factors, especially the makeup and characteristics of the land, and which contaminants are present.
For example, some contaminants will more readily adsorb to the surface of sand or clay particles, which is the way chemists describe one substance sticking to another.
Removing them may require the introduction of a chemical agent, or might involve simply flushing sufficient water through the soil to gradually lower the level of contamination to acceptable levels.
After any remedial action is taken, a soil test – or several if covering a large area – must be subsequently conducted to ensure that the cleanup has succeeded as planned.
Midwest Labs can provide you instructions on how to properly collect samples for your initial test, analyze your samples with a battery of tests that will vary depending on your site, produce a detailed report based on the results, and more importantly, give you a professional interpretation of what those results actually indicate.
From there, we can suggest a plan of action in consultation with our clients to return the land to its desired state.
Whether that means making the land suitable for the crop or livestock of choice, getting contaminants down to safe, legal levels, or where the soil test indicates contamination is significant, but of only minor real concern, alternative measures to a full clean up, such as how to build over the affected land in such a way that it will not adversely affect human health or the environment.