Mammoth

Audit Analysis

Climeworks Mammoth is a geologically stored carbon project in Iceland with a VVB-confirmed investment additionality test and a reasonable leakage treatment for its project type. However, the verification report identifies a significant uncertainty calculation error, the absence of a buffer pool, missing safeguards (no FPIC, no grievance mechanism), and multiple documentation gaps that collectively moderate confidence in the credit's robustness.

Project Description

Red Flags

• ⚠Uncertainty was underreported: the verification report notes the value should be 28.07 tCO2eq ±11.59% rather than 13.14 tCO2eq (±46%), indicating a material error in the Root Sum of Squares calculation
• ⚠No buffer pool percentage is stated in any available document, leaving permanence risk unmitigated despite a reported reversal event of 0.029 tonnes CO2
• ⚠Two verification reports (Dec 2025 and Jan 2026) report materially different ERR figures (278.3 vs 82.3 tonnes), creating uncertainty about the correct verified quantity
• ⚠No grievance mechanism and no FPIC process were conducted, despite safeguards being mentioned in the documents
• ⚠The risk register did not explicitly address CO2 transport risks and geological storage until corrective action was required

Credit Vintages Exhausted