On a tiny scale I store them via humification in the top soil. In agriculture they manage the humus content of their soil anyway, for example in greenhouses the

On a tiny scale I store them via humification in the top soil. In agriculture they manage the humus content of their soil anyway, for example in greenhouses they might have 20% instead of 2% in the surrounding fields. Someone armed with enough VC money could possibly do that on a really large scale and even monetize it via carbon offset certs and then just throw the C rich output of their giant bioreactor into the bottomless pit.