The tenants complaint is that they have had the powder bath toilet back up with black water 3 times in the last year and when it happens there is a bubbling noise that comes from the kitchen sink We tested the system and nothing is backing up or acting clogged After testing the system spoke with tenant and they said the last time it happened it was raining We found the home is on septic and the tank is in the front yard we found a location in the yard that is very wet and we probed and found it is right over the tank At this point the a septic company needs to be sent out to assess the tank Job not completed No estimates are needed