Ethanol blended fuels have been mandated for use since Dec. 2007. Widespread accepted use occurred in tangent with the mandate. In 2007 and 2008 tank inspectors started reporting excessive corrosion in sumps for underground storage tanks for these ethanol blended fuels. Research by the EPA determined that the corrosion was being caused by acids that were created by bacteria that were feeding on ethanol in the sumps. Ethanol vapors, released during routine minor vapor leaks in the sump, combined with moisture to form dilute ethanol, a rich food source for omnipresent acetobacter. Traditional maintenance fixes cannot eliminate the problem.



Zerust specializes in development and deployment of unique corrosion inhibitors for tough client problems. For ethanol induced corrosion, Zerust recommends the Sump Saver solution which is implemented in three steps.

Product Applications

Step 1 Preparation:

The sump is inspected by a qualified sump technician for any active fuel leaks, loose fittings or torn boots and these are addressed appropriately prior to application of Sump Saver Kit products. Any liquids standing at the bottom of the sump are removed. Bulk/loose corrosion on the metallic parts in the sump are removed using non-sparking tools as per relevant guidelines. This is done to remove corrosion product and to expose the metal surfaces to be protected. All metallic surfaces including pipes, motor head and fittings must be dry.

Step 2 Zerust Axxanol™ Spray-G Application:

Zerust’s Axxanol Spray-G, a special grease with proprietary corrosion inhibitors, is sprayed over the metallic parts, including the sump motor, riser pipe, valves, tubing and pipe connectors. Care is taken to avoid sensors and electrodes. This is an annual application.

Step 3 Zerion Sump Saver Application:

Zerust Sump Saver, a unique liquid inhibitor, is sprayed over all the parts inside the sump including over the Spray-G. The product is also applied on the sump walls and non-metallic parts where acid condensate could be present. Any remaining Sump Saver liquid is poured into the floor of the sump.

Step 3 is repeated monthly.

Annual Cycle:

At the end of the yearly cycle, the Axxanol Spray-G grease should be removed from the sump by wiping with a rag or similar.

Steps 2 and 3 are then repeated as above.



  • Increase the life of sump assemblies of piping sump equipment of underground storage tanks
  • Reduce maintenance related down time
  • Easy to apply system does not require trained personnel
  • Multi-part solution to deal with unpredictable environment

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