MMB beat me to it: The chorus runs:

It isn't really garbage till you mix it all together;
It isn't really garbage till you throw it away.
So separate you paper, plastic, compost, glass and metal--
And then you get to use it all ano o ther day. [That syllabification, not misspelling.]

I will put in a call to Dan Einbender and ask him to post the rest of the song.