Soil Load Analysis

Soil contamination is a grave public health concern, and this concern is exacerbated when industrial sites, such as power plants or steel manufacturing facilities, are located near residential areas. Soil load analysis is an important environmental protection measure to ensure that the amount of contaminants in a certain area of ground does not pose a public health threat. Local governments and public health agencies should be well versed in soil load analysis procedures to ensure the long-term health of their residents.

Significance

• Contaminants trapped in soil can harm humans and animals if they come into physical contact with the soil, inhale contaminants attached to dust particles or eat food that has been grown in contaminated soil. Soil load analysis is the first step in cleaning up a contaminated area and making it safe for people.

Types

• There are a variety of soil load analysis procedures. These procedures vary according to the type of contaminant suspected, such as lead, sulfur or arsenic. These analyses are generally performed at laboratories that possess the highly specialized equipment necessary to measure the presence of specific contaminants. Soil sampling procedures include general soil sampling (taking samples at regular intervals along a grid pattern), berm sampling (sampling soil from visually identifiable berms) and firing line sampling (sampling along a straight line).

Effects

• Once a soil load analysis has been completed, a municipality may decide to go ahead with cleanup of the contaminated area. If the municipality can apply a treatment to the soil to rid the contaminants, the soil can be treated in place or excavated and then treated. Excavation is also utilized whenever a municipality decides to discard the soil. The soil may also be contained by the use of plastic covering to prevent contaminants from spreading.

Size

• The sample sizes for soil load analyses are not large. Four dry ounces of soil is a large enough sample for 2,000 cubic feet. However, for suspected contaminants particularly harmful to humans, such as lead, it's not unusual to see about 30 soil samples taken over an area of 150 cubic feet.

Considerations

• Soil samples for soil load analysis should be collected from at least 2 inches below ground surface, as wind and other forces of erosion acting on topsoil may give unreliable readings during analysis. Analysis procedures can also be performed on crops grown in areas suspected of contamination. Contact your local municipality to see if there is a specific laboratory used to conduct soil load analyses.