Methane transport in agricultural soil after injection of isotopically-enriched methane in the sub-surface.

Small quantities of radioactive methane (CH) may be released over prolonged periods from geological disposal facilities for radioactive waste. The impact of this release depends on the capacity of soil to oxidise CH to CO during transport from the sub-surface to the atmosphere. We investigated this capacity by pulse-injecting isotopically-enriched methane 50 cm below the surface of an agricultural soil in central England.