Expo's rules

Expo Milano 2015 estimates an overall waste production of 17,000 tons during the six-month event, with over 132 tons on the busiest days and 75 tons on the other days.

Consistently with its Charter and sustainability standards, Expo 2015 is committed to providing high rates of separate collection (100% of organic fraction and 70% of other fractions) and reuse by integrating the waste-collection chain into Milan’s broadest door-to-door separate-collection system for the 5 main fractions, i.e. paper/cardboard, glass, wet waste, light multi-material (plastics and metals) and mixed residual waste.

All of the waste produced by Expo Milano 2015 will therefore be recycled, with no primary waste disposed of in landfills.

Expo 2015’s guidelines lay down that:

Any disposable tableware (dishes, cutlery, cups, boxes, trays, ice cream and coffee spoons, etc.) will be made of EN 13432-certified biodegradable and compostable materials, so they can be disposed of in composting and digesting plants.
Unconsumed hot meals will be given to a non-profit organisation for free, to reduce the organic fraction from urban solid waste.
About 400 garbage-collection areas will be set up in all 84 districts, where fractions will be collected more often in peak times.
Installation of water coolers.

(source: http://www.expo2015.org/it/cos-e/sostenibilita/il-rapporto-di-sostenibilita-di-expo)