Carbon removal methods CO2 Removal Certificates (CORCs) are based on Puro Standard's science-based quantification methodologies for carbon removal. has pioneered five methodologies for certifying carbon removal. Each methodology outlines the carbon removal method system boundaries, formulas for calculating how much carbon is removed, environmental safeguards, and the documentation needed for independent verification of CORCs to be issued to a project.



100+ years

Biomass or biowaste heated in the absence of oxygen (a thermochemical conversion named pyrolysis). A very stable, solid form of carbon that can endure in soil for hundreds or thousands of years. Multiple uses at potentially industrial volumes, for example, as greenhouse additive, in soil regeneration and in stormwater or wastewater treatment.

Biochar activities can also

Increase recycling and utilizing bio-waste

Improve agricultural productivity

Geologically Stored Carbon


1,000+ years

Geologically Stored Carbon (GSC) involves capturing carbon dioxide (CO2) and storing it in underground geological formations to permanently remove it from the atmosphere. The process includes capturing CO2 from sources like the atmosphere or bioenergy facilities, transporting it to a storage site, and 
injecting it into deep geological formations, where it is securely trapped by impermeable rock layers and undergoes further chemical and physical processes to ensure its containment.

GSC activities can also

Improve sustainability of industries

Reduce adverse environmental impact of cities

Carbonated Materials


1,000+ years

By reacting with CO2, these materials mineralize and form carbonates, thereby trapping and storing the carbon dioxide for geological timespans. Offering a pathway to transform the environmental impact of an entire industry while utilizing industrial byproducts and waste materials such as steel slag mine tailings and alkaline waters.

Carbonated materials activities can also

Increase recycling and utilizing industrial waste streams

Transform an entire industry

Enhanced Rock Weathering


1,000+ years

A process that accelerates natural rock weathering that usually takes thousands of years. Rock weathering begins with the reaction between water, carbon dioxide and silicate rocks which breaks down the rock to then form bicarbonate, a durable form of carbon. When spread on agricultural land, the rock can be highly beneficial and can increase crop yields.

Enhanced rock weathering activities can also

Increase soil fertility and crop yield

Increase the buffer capacity in ocean

Terrestrial Storage of Biomass


100+ years

The storage of woody biomass in conditions that prevent decomposition and maintain carbon locked away for at least 100 years. A new innovative approach to immobilise carbon, that offers a unique opportunity for large-scale, affordable carbon removal.

Terrestrial Storage of Biomass activities can also

Enable landscape restoration

Reduce risk of biomass clogging waterways or roads

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