Your tank bund checklist before next winter.
Spring is the only practical month to inspect a bunded oil tank. Six things to check before the autumn fills.
Bunded tanks (the kind with an outer skin to catch leaks) are required on most new installations and recommended on all older ones. They protect you from prosecution if your tank ever leaks into a watercourse — a six-figure liability.
Spring is the only sane time to inspect them. Tank levels are at their lowest, weather is dry, and you have six months before the autumn fill rush. Run this checklist now.
1. Is the bund itself dry?
Open the inspection lid. Any liquid in the bund is a fail — either rainwater (poor seal) or leaked oil (active leak). Pump it out, identify the source, fix before the next fill.
2. Are the seals around the gauge and fill neck intact?
UV makes rubber brittle. A cracked seal is the #1 cause of bund water ingress. Replacement seals are £8–£15.
3. Is the bund vent clear?
Wasps love these. A blocked vent will pressurise the bund and split it. Look for nests, debris, ice damage.
4. Is the tank gauge accurate?
Drop a dipstick. If your gauge reads more than 5% off, replace it before the next order. We’ve had customers run dry because of failed gauges.
5. Is the tank base level?
Check with a spirit level. Tank stands settle over time. A 5-degree tilt loads the welds and shortens tank life by years.
6. Is access for the tanker still clear?
Walk the route the driver takes. Has a hedge grown? Did you add a fence? Can a 7.5T rigid still reach the fill point with its 30m hose? If not, tell us before you order — we’ll match you to a smaller tanker.
If you find a problem
OFTEC-registered technicians do tank inspections for £80–£140. Worth it every other spring. We can recommend one in your area.