Although the Underground Storage Tank Management Division has begun the use of the Alternative Fuel Installation Application/Conversion Notification (pdf) checklist, compatibility between alternative fuels and typical UST system components continues to be an issue. Our support for the industry includes making sure that the proper safeguards are in place so that the positive environmental contributions of renewable fuels are not negated by using equipment that may not be compatible. Without the use of compatible equipment, your UST system could degrade and a release could occur. Components and equipment used in conventional fuel systems are time-tested for compatibility and are readily available.
Ethanol-blended fuels do not have the same characteristics as conventional fuels. For example, soft metals such as aluminum (commonly found in conventional systems) are not compatible. Some materials such as polyurethane, adhesives (used in older fiberglass tanks and piping), and certain polymers may not be compatible. Leak detection equipment, such as automatic tank gauge probes, need to be alcohol compatible and the tank gauge system must be properly calibrated for ethanol. There are also numerous issues with internal linings, ranging from what is or is not known about the lining material to existing cracks and abrasions in the lining wall.
Whether converting an older tank or installing a new tank system for use with ethanol-blended fuels, please use the following procedures:
- Obtain the Alternative Fuel Installation Application/Conversion Notification (pdf) Checklist and have it completed and approved by the Division prior to operation of any alternative fuel system.
- Verify that all components listed on the checklist are compatible.
- Make certain that all fittings, connections, sumps, and spill containment covers are tight so that no vapors can escape and no water can enter the tank system.
- Clean the tank to remove all sludge from the bottom of the tank. Dispose of any sludge in accordance with Solid and Hazardous Waste guidelines .
Ultimately, the equipment and components must be compatible with the alternative fuels that you intend to use. The following is a list of equipment that must have an appropriate alternative fuel model in place:
- Tanks (lined tanks are not acceptable)
- Piping (older fiberglass containing adhesives, installed prior to the 1980's are not allowed)
- Drop tubes and Drop tube shut off valves (must be anodized, not pure aluminum)
- ATG probes
- Submersible turbine pumps
- Nozzles, hoses, breakaways, and emergency valves on dispensers
Blends of biodiesel greater than B20, may cause issues with rubber components. The same procedures should be followed for the submittal of the Alternative Fuel Installation Application/Conversion Notification (pdf) Checklist for biodiesel fuels.
It is the tank owner's responsibility to ensure that all procedures are followed in order to minimize the potential for a release to occur due to incompatible equipment. If in doubt, contact the Division prior to introducing ethanol-blended fuels into a tank system.
Eric Cathcart, Manager, 803-898-0633