Open Procedure Aimed At The Conclusion Of A Framework Agreement For The Assignment Of Emergency Maintenance Interventions For The Mitigation Of The Critical Issues Existing In The "Vecchio Allacciante" Collector For The Passage Of Wastewater And Partial Restoration Of The Reception Capacity Of The Pantano D'Arci Purification Plant - Municipality Of Catania - Cipess Resolution N. 40/2024.