Biochar in urban applications
As cities struggle with compacted soils, contamination, runoff, and also high rates of tree death from increasing drought, biochar offers a solution to improve the long-term quality of landscapes and infrastructure.
Biochar is increasingly being integrated into urban environments due to its porous structure that improves water-holding capacity, and its high surface area that allows it to retain certain nutrients, metals, and pollutants. Cities can benefit from the many co-benefits of the material by incorporating it into soils and landscapes, green infrastructure, filtration systems, and remediation projects.
Biochar and PFAS contamination
Per- and polyfluoroalkyl substances (PFAS) — commonly known as “forever chemicals” — are a class of synthetic chemicals used in industrial processes and consumer products for decades. They are persistent in the environment and have been detected in soils, surface water, stormwater runoff, and groundwater in many urban areas.
Certain biochars have demonstrated the ability to adsorb some PFAS compounds; while biochar does not destroy PFAS, it can immobilize them, reducing their toxicity and plant uptake in soils. Long-term management planning is required, as eventual handling and disposing of the saturated biochar is unavoidable.
