What is the recommended clean-up procedure for contaminated soil?

The recommended clean-up procedure for contaminated soil involves removing the top 2-3 inches of soil and disposing of it as hazardous waste. This method is effective because contaminated soil can pose significant health and environmental risks, particularly if it contains harmful chemicals or pathogens.

By removing the top layer, you effectively eliminate the most contaminated portion of the soil, which is crucial in preventing exposure to harmful substances. Disposing of this soil as hazardous waste ensures that it is handled in a manner that complies with environmental regulations, reducing the risk of further contamination or exposure.

The other options are less effective or inappropriate for dealing with contaminated soil. For instance, digging a deep trench to bury the soil may seem like a solution, but it can lead to the contamination leaching into groundwater or nearby areas. Covering the area with new soil does not address the underlying issue, as the contaminants will still be present in the old soil. Lastly, using chemical treatments to neutralize contamination can potentially introduce additional chemicals into the environment and may not be effective for all types of pollutants. Hence, the correct approach is to physically remove and properly dispose of the contaminated material.