Printable version

Gasoil Storage Tanks: Terminology Matters!

Operators have fallen foul of compliance requirements because they described their (perfectly legal) tanks inaccurately.

Data centre operators have recently encountered problems relating to their oil storage tanks. Among other requirements, regulations stipulate that tanks must have secondary containment (often described as bunding) equivalent to 110% of the primary tank volume. This is to ensure that all spills can be fully contained. Some tanks are single skinned with an open bund providing containment, but more commonly operators use integrally bunded tanks. Both these models can be seen in the diagrams below, extracted from the Environment Agency’s Pollution Prevention Guidelines (PPG2), 2010.

Operators should be aware that a bunded tank is not the same as a double skinned tank. Double skinned  oil storage tanks tend to have a second skin close to the primary skin, usually to improve structural integrity. A second skin is not a bund and a double skinned tank of this type does not comply with current regulation (unless there is an additional bund). If your gasoil is stored in this kind of tank then you need to take action to change it.

However, failure to comply with regulation is not the problem that operators have alerted us to. The issue is one of terminology: some operators erroneously described their (perfectly legal and compliant) integrally bunded tanks as “double skinned”.   Environment Agency inspectors view such tanks as non compliant and automatically assume that the site in question is failing to meet regulatory requirements. The result is a lot of wasted time, angst and suffering.

This note explains how to get it right. Please click below do download it in full.



Channel website:

Original article link:

Share this article

Latest News from