Silicate rocks including basalt and olivine are crushed to increase surface area and spread on agricultural fields. Rainwater and soil acids dissolve the rocks, releasing alkaline minerals that react with atmospheric CO2 to form bicarbonate. The bicarbonate is transported by water to oceans where it remains permanently stored. Rock weathering also releases beneficial minerals including magnesium, calcium, and potassium that improve soil fertility.
Permanently removes CO2 from the atmosphere with storage lasting 100,000+ years, improves agricultural productivity through soil pH correction and nutrient addition, and utilizes abundant rock resources available globally. ERW provides measurable and verifiable carbon removal. The process works with existing farming practices requiring minimal behavior change.
Requires massive quantities of rock crushing and transportation creating logistical challenges, potential soil and water impacts from heavy metal content in some rocks, and verification of CO2 removal requires complex monitoring systems. Slow weathering rates limit short-term carbon removal. Environmental impacts of large-scale rock mining need assessment.