More and more localities around the country are passing laws requiring the recycling of garbage and waste. If your locality has already enacted a recycling law, make sure your leases spell out what a resident's responsibilities are and also what your rights are.  You will avoid confusion and disputes down the road: A resident will know exactly what is expected of him/her.  And you do not want to get caught in the middle, by getting fined for a resident's non-compliance or having to clean up after a resident who will not cooperate.  Even if there is no garbage-recycling law in your area, it is smart to be prepared in case one is adopted.

A good clause would contain these elements:
    The resident agrees to comply with all current and future recycling laws.
    The resident agrees to sort, separate, and recycle garbage into whatever categories the law prescribes.
    You, as the owner, may refuse to collect the resident's garbage if he/she does not separate it properly, and require him/her to arrange and pay for its collection.
   
The resident agrees to pay any fines or penalties either you or he/she may get because he/she failed to sort the garbage properly.  This prevents you from having to pay for the resident's failure to comply with the law.