B5.3.3 How do I know if Land is Contaminated?


If you are excavating soil (digging) you may notice signs of contamination. These could include:

  • Soil of unusual colour.
  • Strange or unexpected particles in the soil.
  • Evidence of buried waste.
  • An oily sheen on groundwater entering the hole.
  • Strange odours.


Desktop surveys may help identify areas of potential contamination. Local Authorities may hold historic records and the Environment Agency may hold records of certain activities (landfill sites, environmental permits). If an area was once used for what is known to be a highly polluting activity that is a known source of contamination, you can expect that contamination is likely; whereas an area that had only ever been used for agricultural purposes is much less likely to be contaminated. However, the only way to be certain is to test the soil. This usually involves taking core samples from different areas within a designated area (or site) and using a laboratory for analysis of known pollutants.