Is it possible to generate CORCs from both biochar (BCH) and enhanced rock weathering (ERW) in parallel by applying biochar and rock powder to the same fields?

In principle, yes: there are no rules specifically forbidding spreading biochar and rock powder on the same fields. However, while audits can be separate or grouped, the two projects must be clearly separated with respect to carbon accounting, system boundaries and project emissions, etc, resulting in two completely separate production facilities. Importantly, special attention needs to be paid to avoiding double counting.

Note further the different roles of the CO2 removal suppliers in each methodology: in ERW, the CO2 removal supplier is the entity responsible for spreading the rock powder, whereas in BCH2025, the CO2 removal supplier is the biochar producer rather than the entity utilizing it. These roles, like all other rules in the two methodologies, must of course be followed, and will be assessed separately. Finally, note that combined removal pathways could incur additional monitoring needs: for example, while we do not foresee a negative effect of rock powder on biochar, we do advice monitoring the impact of biochar on ERW (e.g. through changes in pH).