Marine CO2 Mineralisation

Methodology overview

Technology-based methodology for permanent CO2 removal through conversion of captured CO2 into stable marine carbonates, providing geological-timescale storage.

Eligibility criteria

• ●Activity prevents pollutant entry to the marine environment — collection downstream of marine entry is excluded except for ghost gear in active fishing zones.
• ●Mass-balance accounting from source to interception point with documented chain of custody.
• ●Pollutant types limited to: macro / micro plastics, abandoned / lost fishing gear, and quantifiable agricultural nutrient runoff (N, P).
• ●Project activity is not legally mandated or already remunerated under EPR or polluter-pays schemes.
• ●End-of-life processing is verified — landfill or incineration without energy recovery does not qualify; accredited recycling or material recovery required.
• ●Permanence Option C: buffer pool drawdown to cover misclassification and double-count risk.
• ●Contribution-first claims; no neutralisation of any party's pollution footprint.

Quantification approach

Carbon pools and crediting metrics

• ●Avoided plastic-degradation methane / CO2 (very small, reported only)
• ●Avoided processing emissions (where recycled material displaces virgin production — verified, not assumed)

Equations (in plain language)

• 1.Prevented mass = (mass intercepted, kg) × (counterfactual escape probability) — counterfactual is regional and conservative.
• 2.Function gain = (prevented mass, kg) × (gear-class or polymer-class mortality / impact coefficient).
• 3.Avoided-emission side claim = (mass recycled, t) × (lifecycle delta vs virgin production, kg CO2e / t) where the recycler provides chain-of-custody documentation.
• 4.Double counting check: serialised manifest, GPS-tagged collection waypoints and intake-weighbridge records all required before issuance.

Reference methodology — starting point

Reference points include UNEA-resolved guidance on plastic pollution monitoring, the GESAMP marine litter assessment frameworks and FAO ghost-gear marking guidelines. These are starting references being improved upon — MCC F04 adds mandatory chain-of-custody and EPR-overlap testing.

Where MCC improves on the reference

• ✓Hard EPR / polluter-pays overlap test at PDD stage and re-tested annually.
• ✓Serialised, GPS-tagged manifest required from collection waypoint to recycler intake.
• ✓Counterfactual escape probabilities are regional, not global averages.
• ✓Function-equivalent claims (avoided mortality from plastic / ghost gear) are crediting unit; carbon side claim is reported but secondary.

Monitoring requirements

Required data sources

• ●Weighbridge intake records — every consignment, signed by accredited operator
• ●GPS-tagged collection waypoints — every collection event
• ●Drone or satellite verification of collection sites — quarterly
• ●Polymer / gear-class characterisation samples — every 1,000 kg or quarterly
• ●Recycler material-flow report — quarterly, with mass-balance reconciliation
• ●Water-quality monitoring (N, P) for runoff projects — continuous in-stream sensors

KPIs that must be tracked

Eligible co-benefits — SDG mapping

F-family F04 contributes to the following Sustainable Development Goals. Indicators flagged as required must be reported at every verification; optional indicators may be claimed where the project chooses to report them.

Public consultation and community engagement

30-day public consultation. Where collection involves informal-sector workers, a documented just-transition / decent-work plan is required and re-confirmed at every verification. EPR-overlap audit results are published with the consultation.

Methodology change log