"This giant bubble on the island of Sardinia holds 2,000 tonnes of carbon dioxide. But the gas wasn’t captured from factory emissions, nor was it pulled from the air. It came from a gas supplier… “The facility compresses and expands CO2 daily in its closed system, turning a turbine that generates 200 megawatt-hours of electricity, or 20 MW over 10 hours.”



So you concern is the ecological impact should this bubble fail and the entirety of the CO2 is released to the atmosphere as pollution? Did you even read the article? They discuss that.
First, a full on failure would be rare. Then, a full on failure of 100% loss of the closed loop CO2 is equivalent to 15 round trip flights of a jet flying from New York to London. To put it in perspective there about 250+ flights of this length per day from London, with many being much much farther.
So you’re comparing the impacts of a once in a lifetime nuclear power plant failure to the impacts of another source 1/16th of something that already happens every in one airport. Your logic is why out of whack on this if this is your concern with the bubble.