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How do I fix my contaminated soil?

Soil contamination implies that the concentration of a substance (e.g. nutrient, pesticide, organic chemical, acidic or saline compound, or trace elements) in soil is higher than would naturally occur (See also soil pollution).

Soil pollution refers to the presence of substances at concentrations above threshold levels where they become harmful to living organisms (See also soil contamination). Soils break down pollutants and limit groundwater and surface water pollution. Indeed, soils hamper pollutants leaching into the groundwater and limit their transport to surface waters.

To prevent accumulation of and/or mitigate exposure to soil contaminates:

  • Use clean soil and compost. If you are concerned about contamination in your garden soil, consider having it tested by a New York State-certified laboratory.

  • Use raised beds.

  • Build beds deep enough for the roots of your crops, and maintain them by adding compost often.

  • Avoid treated wood.

  • Railroad ties, telephone poles, pressure-treated wood and some painted wood contain chemicals that can get into soil.

  • Maintain soil nutrients and pH. Healthy garden soils have a good nutrient balance and a pH near neutral (6.5 – 7).

  • Cover (or mulch) soil.

  • Use compost, straw or bark mulch in garden beds, and stones or wood chips in paths and non-growing areas. This helps reduce soil splash, dust and tracking of soil home.

  • Keep an eye on children.

  • Make sure children do not eat soil or put dirty toys or other objects in their mouths. Young children can be more sensitive to certain chemicals in soil, such as lead.

  • Leave the soil in the garden. Avoid bringing garden soil into your home. Remove soil from garden tools and harvested vegetables while at the garden, and change your shoes before going indoors.

  • Wash your hands.

  • Wash up after gardening, and have children who play or work in the garden do the same. Consider wearing gloves, and remember to remove them when leaving the garden.

  • Wash and/or peel produce. Wash vegetables thoroughly –especially leafy and root crops, which are more likely to have soil on them. Consider peeling if appropriate.

  • Put a barrier under play areas. Separate children’s play areas from underlying soil with landscape fabric or other durable material. Put clean play materials such as sand or wood chips on top. Check the barrier over time to be sure underlying soil isn’t mixing with play materials.