AutoPumps are air-powered positive displacement pumps that require no surface timer-based controllers, bubblers, or sensors in the well to operate. The pump is activated by an internal float in response to the natural well recharge. Because the AutoPumps fill by gravity and discharge by air displacement, no emulsification is created during its operation. The high-performance pump has been proven to withstand temperatures up to 250 degrees Fahrenheit (121 degrees Celsius) and increase run time between cleanings.


In the fill cycle, the fluid pushes the inlet check-valve open and fluid enters the pump. As the fluid level rises, air is expelled through the exhaust air valve and the internal float rises to the top of its stroke. In this upper position, the float triggers a lever assembly, which closes the air exhaust valve and opens the air inlet allowing air to enter and pressurize the pump.

During the discharge cycle, with the air inlet open, air pressure builds up within the pump body. This causes the fluid inlet check-valve to close and forces the fluid to be displaced up and out of the fluid outlet. As the fluid level falls, the float moves downward to the bottom of its stroke. In this lower position, the float triggers the lever assembly to close the air supply and open the air exhaust valve. And a new cycle begins.

Comparison tests have shown that various landfill sites, which are dealing with the most severe applications, are able to significantly lower their pump maintenance costs using QED’s new AutoPump® AP4 Ultra.

Left: Extended uptime: Proprietary finishes reduce buildup and extend the time between cleaning.
Right: Minimized downtime: Special non-stick finishes require less than half the time to clean than traditional pumps.


The design of the highly-reliable, low-maintenance AP4 Ultra pump includes specialized materials to deliver pumping performance in high-temperature landfill leachate and condensate risers and groundwater remediation wells. Proprietary non-stick finishes and electropolished surfaces in the new AP4 High-Temperature Ultra pump reduce solids buildup, increasing the run-time interval and making it much faster and easier to clean; operators often need only to spray the pump with water and lightly wipe it clean. As a result, users experience longer run times, reduced maintenance costs, increased safety of service personnel, and a boost in project productivity.

Left: 316 Stainless Steel: All metallic parts are 316-grade SS for greater corrosion resistance.
Right: Improved valve stem connection: No fasteners; no cotter pins. Exhaust seat is easy to adjust.

All non-magnetic metallic parts of the AP4 Ultra pump are 316-grade Stainless Steel with engineered polymers to resist corrosion and attacks by harsh leachates, free-phase and dissolved fuels, BTEX and MTBE. QED also offers a large selection of pump tubing and accessories rated for high-temperature applications to ensure consistent performance of the entire pump system.


The AP4 Ultra pump is available in several different configurations to best meet the needs of the individual application. For more information, visit QED’s online Pump Maintenance Cost Comparison Calculator, which makes it easy to estimate savings and predict the payback period for switching from conventional pumps to a new AP4 Ultra pump system.

For more information:

Q.E.D. Environmental Systems, a subsidiary of Graco Inc., is a leading manufacturer of innovative environmental pumping systems, landfill products, landfill gas products, and air strippers for use at landfills, mines, oil refineries, and other industrial sites, as well as hazardous waste cleanup sites. QED serves customers from support centers in Michigan and California. For more information, visit, call 734.995.2547, or email
Did you enjoy this article?
Subscribe to the FREE Digital Edition of Modern Pumping Today Magazine!