Mumford Septic and Waste Disposal Services of Rhode Island With over 8000 septic customers in Southern Rhode Island, Mumford Services is one of Rhode Islands most well-known and experienced sanitation companies. The company is still family owned and operated and is very proud to offer top notch service for: Septic pumping, complete rebuilding of septic systems, roll-off containers / dumpster available in multiple sizes for commercial sites and home-owner clean-outs, 4 types of portable toilets; "construction", "wedding party", "Handicap accessible" and "flush units with running water".