From the platform the CO2 is injected via the existing well into a gas reservoir 3.5 kilometres under the sea bed. The gas reservoir is sealed under strata including salt, lime, sand and clay.
These kept the original natural gas sealed in the gas reservoir for millions of years. The sealing strata will also ensure the permanent storage of C02. The gas reservoir will be filled with CO2 up to 200 bar. This will bring ambient pressure to around 350 bar. Next, the gas reservoir will be closed by pouring a special concrete into several hundred metres of the well.