Eion - Twinterstellar 3021

Audit Analysis

Twinterstellar 3021 is an Enhanced Rock Weathering DAC project with strong inherent permanence (ocean bicarbonate durability >1,000 years) and VVB-confirmed additionality, but the verification report surfaced six material findings—including a non-robust flux method, an ERA completed after application, and 18 of 122 fields flagged as outliers—indicating meaningful methodological and operational gaps. The project delivered only ~19% of its pro-rata PDD expectation for the elapsed monitoring period, which is conservative but raises questions about the original estimate's accuracy.

Project Description

Red Flags

• ⚠The flux method for background weathering was found not to be scientifically robust by the VVB; the project switched to the soil method after the fact, and the PDD's counterfactual weathering figure still needs updating.
• ⚠The Environmental Risk Assessment was not completed prior to rock application; Puro.earth granted an exception, and the initial ERA review did not consider radionuclide or asbestos risks.
• ⚠18 of 122 monitored fields (~15%) were identified as outliers for soil clay content, and aqua regia digestions were found to underreport chromium concentrations, raising data-quality concerns across the monitoring dataset.
• ⚠The PDD estimates a lifetime removal of 12,285 tCO₂e, yet only 748.31 tCO₂e was verified over the first ~1.6-year monitoring period—roughly 19% of the pro-rata expectation—suggesting the original estimate may have been overly optimistic.

Credit Vintages Exhausted