Can you have a garbage disposal on a well?

Your source of water should not be an issue. But it may be an issue if you are on a home septic system. Some say not to use a garbage disposal when you are on a septic system, but you can. I know of some in use with septic systems and they have not had a problem. Generally you should have your tank pumped every five years. With a garbage disposal on the system you should have your tank pump every two or three years,