GENTLE REMEDIATION OPTIONS (GRO): A PILOT STUDY AND BROADER IMPLICATIONS FOR SUSTAINABLE AND RISK-BASED LAND MANAGEMENT OF CONTAMINATED SITES

Keywords: Contaminated sites; Gentle remediation options (GRO); Soil functions; Ecosystem services; Nature-based solutions (NBS)

Aim: to present ongoing work and preliminary results in a pilot study application of gentle remediation options (GRO) – i.e., nature-based risk management strategies/technologies that use plants, bacteria and fungi to effectively risk management as well as improved soil functions – to manage risks posed by DDT contamination in the soil of a previous tree nursery site and improve soil functioning.

To test the effectiveness of selected GRO strategies to manage risks due to DDT contamination and improve soil quality, a pilot-scale field experiment was established at the site by planting suitable plants, in combination with biochar as a soil amendment. Physical, chemical and biological indicators were selected to assess both the fate of the contamination as well as resulting impacts on soil functions. Preliminary results from the first growth season indicate that biochar can have significant impacts on the quality of the soil in terms of improving soil fertility and improving microbial activity as well as reducing uptake of DDT in vegetation and soil organisms like earthworms. Effects from the different plants were less pronounced after the first season; however, certain plants show potential to extract DDT while others may be more useful to improve soil quality.

This risk-based ecological approach is often referred to as ‘phytomanagement’ – i.e., the long-term combination of GRO with beneficial land use (e.g., biofuel crop production) to gradually reduce risks at contaminated sites while also restoring ecosystem services. In terms of the topical session, phytomanagement is highly relevant to bring into the conversation as a proactive land management strategy that combines the broader fields of sustainability and geoscience.

Further information can be found here: Gentle Remediation Options (GRO) for Managing Risks and Providing Ecosystem Services at Contaminated Sites https://research.chalmers.se/en/publication/526431 (chalmers.se)