I've been doing a lot of work on our Environmental aspects and impacts recently and waste management is one of those key areas.
To start with, you really need to walk the site and identify all the individual waste streams / types. In my case these fall into the following catagories:
VegetableCardboard
Paper (seperate from cardboard due to the nature and area of waste production i.e. cardboard on production floor and paper in office environments)
PlasticsHazardous waste (paints, oils, chemicals, mostly ex. engineering / maintenance)
General waste from general waste bins around site
Wood
Metal
WEEE (Waste Electrical & Electronic Equipment)
Having identified all waste groups, decide in the most effective collection / seperation method and what type of segregation you are going to employ (receptical type / colour / area)
Then plan for the storage of these materials in a manner which will pose no risk to your processess, people or the environment.
You will then need to investigate appropriate collection and disposal as per national legislation. Ensure any waste carriers are correctly licensed for the carriage and disposal of the waste type as you will be liable if they are not!
You will then need to train out the system to your staff an monitor ongoing that not only does your system work in practice, but that new waste streams don't develope without your knowledge. (this can happen if you change suppliers / processes and new materials are now introduced into the system)
Hope this helps, sorry it's a bit long winded.
Ss