Containment and Storage

Most spill damage is prevented before the spill, by containment that works without anyone doing anything.

Storage principles

• Store liquids in a bunded area with capacity for at least 110% of the largest container, on impermeable hardstanding, away from drains, watercourses and unmade ground.
• Keep bunds empty — rainwater removes the capacity that would have held a spill.
• Seal every penetration through the bund wall; this is the commonest failure.
• Locked or removed drain valves, with a controlled procedure for emptying rainwater.
• Inspect regularly for cracks, especially at the wall-floor joint, and for corrosion of containers.
• Drip trays under taps, pumps, valves and stored drums — cheap and effective for the constant small losses that add up.
• Overfill protection on tanks: high-level alarms, automatic shut-off, and a delivery procedure that does not rely on watching a gauge.

Underground risks

Underground tanks and pipework leak invisibly for years and cause the most expensive contamination. Where they exist, they need leak detection, integrity testing and, ideally, replacement with above-ground alternatives where practicable.