New research out of the Netherlands indicates that the use of biodiesel as a component in diesel fuel blends could be leading to increased corrosion in underground storage tanks that hold the fuel.

A preliminary report (in Dutch) from SIKB, a public-private organization that works on soil issues in the country, asserts that the addition of biodiesel (derived from plant and animal fats, such as recycled cooking oil) to traditional diesel, which became mandatory in the Netherlands in 2007, has led to increased corrosion rates in USTs.

SIKB

New Dutch research asserts that the addition of biodiesel to traditional diesel has led to increased corrosion rates in diesel underground storage tanks.

Bacteria in the biodiesel is likely leading to the increased corrosion rate, SIKB says. The organization also says sulfur in diesel fuel previously slowed bacteria growth, but more recently has been removed, allowing for more microbial growth.

The research involved reviews of 1,400 tank inspection reports from previous years along with, so far, 10 new tank inspections carried out as part of the new study. The tanks studied were not protected with coatings, according to Dutch News. SIKB intends to inspect 20 more tanks before issuing a final report on the matter. The final report is expected later this year.

UST Corrosion in the USA

Increased corrosion in diesel USTs has been a topic of note in the United States in recent years as well, fueled by Environmental Protection Agency research that has shown the vast majority of diesel USTs studied exhibited moderate to severe corrosion. Research in the U.S. is ongoing; the EPA has suggested that microbes may play a role. Increased corrosion in the U.S. also began to surface in 2007.

Biodiesel blends are used in the U.S. but are not mandated in exactly the same way they are in the Netherlands. Some states have laws in place mandating blends based on the amount of biodiesel produced in the state. The Energy Independence and Security Act of 2007 calls for increasing percentages of renewable and biobased fuels to be blended into transportation fuels through 2022.