Poor operations and maintenance procedures for monitoring and removing water from storage tank systems can lead to a number of risks, from fuel quality degradation and resulting poor performance, to microbial contamination and damage to the entire storage system.

All storage tank systems, both underground and aboveground, constructed of any material, and storing nearly any product—gasoline, diesel, residential and commercial heating oils, aviation jet fuel, and others—may be affected.

The potential for damage applies not only to the tank, but also to the entire storage system. And these risks can affect your profits.

Today’s fuels are more susceptible to moisture separation and accumulation. Also, removing lead from gasoline and sulfur from diesel has had the side effect of allowing microbial growth to occur more readily, uninhibited by lead and sulfur.

Ethanol and biodiesel are important in today’s fueling network. However, both are “hygroscopic,” meaning they attract water. That’s why tank owners and operators must be even more diligent in monitoring for and removing water from fuels and storage and dispensing systems.

For all these reasons, it’s more important than ever to conduct regular inspection and maintenance of your entire AST fuel storage system.

Protect Your Fuel Product

  • Inspect your storage tank system frequently.
  • Check for water with automatic or manual tank gauging.
  • Investigate the source of any water found.
  • Remove and properly dispose of any water found or take other corrective action, in accordance with industry recommended practices.
  • Consider alternative methods to control water in fuel and storage system, such as biocides, fuel“polishers,” or corrosion inhibitors.
  • Audit the fuel or product delivery process and the water content.
  • Use water-sensitive filters and watch for slowed-down fueling or dispensing.
  • Employ a qualified professional to periodically examine the inside of the tank.
  • Remove water and sludge and periodically clean the tank, in accordance with industry-recommended practices.

ASTM and CRC Fuel Quality Standards

  • ASTM D6469 Microbial Contamination in Fuels
  • ASTM D2709 Water and Sediment/Particulation in Fuel
  • ASTM D7371 Biodiesel (Fatty Acid Methyl Esters) Concentration in Diesel
  • ASTM D7545 Oxidation Stability
  • ASTM D975 Specification for Diesel Fuel Oil
  • CRC Report No. 667 Diesel Fuel Storage and Handling Guide


Resource Type

  • Guidance


  • Aboveground
  • Generator Base Tanks
  • Maintenance