Here’s a suggestion:
1. Send in the army. Get them to tidy up, placing all the mess in large trucks and transporting it to rubbish dumps in other parts of Italy.
2. While the soldiers are sorting out the mess, impose 9pm to 6am curfew, enforced by the army. Anyone caught out and about is arrested, held for the night, fined, and then sent home. Cars and scooters etc, are confiscated. They will be released upon payment of another fine.

Stop reading, start speaking
Stop translating in your head and start speaking Italian for real with the only audio course that prompt you to speak.
3. Keep tabs on the total cost of the operation – soldiers time, trucks, fuel etc, and then hit everyone in Naples with an ICI surcharge. Income from fines may be used to lower the cost of the surcharge.
Only a suggestion, but, you never know, it may even enhance the rather poor reputation that Italy’s politicos ‘enjoy’ at the moment.
This Naples thing is likely to turn Italy in to laughing stock for the rest of Europe. It’s a national embarrassment. Pure and simple.