Yale researchers have proposed a new method to remove PFAS (forever chemicals) from contaminated farmland at a fraction of current costs, while also capturing carbon dioxide from the atmosphere. The approach involves spreading crushed alkaline rock on soil to raise pH and accelerate PFAS uptake by plants, then converting the harvested plants into biochar, which destroys the chemicals. Estimated cost is about $29,000 per hectare over 20 years, compared to up to $1.6 million per hectare for excavation or thermal treatment. The method addresses two problems at once: PFAS contamination affecting an estimated 1.2 million hectares of U.S. cropland, and the need for scalable carbon removal. Researchers estimate the system could remove 10.5 million metric tons of CO2 per year nationally. The process allows farmers to keep working their land during treatment, unlike current remediation options that render soil unusable. The study was published in PNAS and supported by Yale Planetary Solutions and Yale Ventures.
