An accumulator assembly having a wastewater retention tank defining an interior chamber. A fluid level sensor is coupled to the waste retention tank and configured to sense a level of liquid in the chamber. An extraction pipe extends into the chamber and is coupled to an extraction valve. Coupled to the fluid sensor is a controller that is also coupled to the fluid level sensor and to the extraction valve. The controller is configured to open the extraction valve upon receipt of a signal from the sensor. The accumulator assembly also includes an odor mitigation subassembly in fluid communication with the chamber. The odor mitigation subassembly further includes an air displacement port, an odor filter and an overflow prevention device, the overflow prevention device being in fluid communication with the chamber and located downstream of the air displacement port and upstream of the filter.