# What emissions should an opencast coal mine report besides diesel?

Canonical: https://senseible.earth/answers/opencast-coal-mine-methane-and-diesel

Diesel for dumpers, shovels and drills is usually the largest on site source. Methane released from the coal seam is the second: the IPCC Tier 1 average for surface mining is 1.2 cubic metres per tonne mined, about 24 kg CO2e. Add explosives, grid power for conveyors, and any coal fires.

## Sources to count

- Diesel: litres from fuel logs x 2.68 kg CO2 per litre.
- Seam methane: tonnes mined x emission factor, measured where possible.
- Explosives, mainly ammonium nitrate based, from consumption records.
- Electricity for conveyors and pumps x 0.710 kg CO2 per kWh.

## Methane defaults

IPCC 2006 gives low, average and high factors of 0.3, 1.2 and 2.0 cubic metres per tonne for surface mines, plus a small post mining amount. Convert at 0.67 kg per cubic metre and weight by the methane GWP.

## Contractors

If a contractor runs the fleet, its diesel is the contractor's Scope 1 and the mine's Scope 3, unless the mine supplies and controls the fuel.

## Worked example: methane per tonne

- 1.2 m3 CH4 per tonne x 0.67 kg per m3 = 0.80 kg CH4
- 0.80 kg x 29.8 (AR6 fossil methane GWP100) = about 24 kg CO2e per tonne mined

Uses the IPCC average; a measured factor for your seam is better.

## What Senseible does here

Senseible reads fuel, electricity and freight invoices into a dated, fingerprinted record per site, so each figure you send a buyer can be traced back to the documents behind it.

- [Methane and N2O from diesel](https://senseible.earth/answers/methane-n2o-from-diesel-combustion)
- [Contractor diesel: which scope](https://senseible.earth/answers/contractor-diesel-on-my-site-which-scope)
- [Washery rejects as fuel](https://senseible.earth/answers/coal-washery-rejects-power-co2)

Sources: [IPCC 2006 Guidelines, Volume 2 Energy (fuel defaults)](https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html), [IPCC AR6 WG1, Chapter 7, Table 7.15 (GWP100)](https://www.ipcc.ch/report/ar6/wg1/)

Last reviewed 2026-10-21.