For the drilling and construction stage, concerns over lost circulation above and within the reservoir, plus reactive shales pushed efforts to maximize hole quality for the critical cementing operation. The production casing would be acting as the secondary containment for the reservoir fluid, so avoidance of gas migration and cement damage were high on the operator’s list of concerns. Regulatory pressure envelopes were small and presented a significant challenge to ensure the wells remained gas tight. The production casing was the most exposed casing to reservoir pressure.
Selection of proven technology
Field-proven CemFIT Heal system technology, in use for more than 10 years, was selected for a large project in the north of Italy that would exploit a depleted gas field by conversion to a gas storage field with the drilling
of 14 wells from two clusters above the reservoir.