The Welsh Government has published guidance on the separate collection of waste paper, metal, plastic and glass, in line with the EU legal requirements which came into force on January 1st 2015. 

All organisations responsible for waste collection, including waste collection businesses and local authorities, will be required to collect waste paper, metal, plastic and glass in a way that maximises the amount of materials that can be recycled.  

These four waste materials should be collected separately from each other and from other sources of waste, where this is necessary to maximise the amount of materials that can be recycled, and where technically, environmentally and economically practicable. 

You can read the guidance in full on the Welsh Government website.