Adding sump pump to garbage disposal line

[Mark Forest]

The electric panel in one of my rentals is full. I suddenly need to add a sump pump and the most expedient way is to tap into the 20 amp circuit that controls my garbage disposal and dishwasher. I am not sure, but I think adding the sump pump may cause the circuit to overload. I was thinking of taking out the garbage disposal anyway so I would have one less thing to replace/repair. Do you all keep the garbage disposals or pull them?

Thank you for your help. This is really the LAST project before I get this one rented out.