A pipe burst at the pump outlet between a container and a shop area in an electronic components plant. Before closing the tank foot valve, 2,500 litres of hydrochloric acid seeped into a retention basin that, upon HCl attack, lost its seal around one of the sluice gates. A CMIC (Mobile Chemical Response Unit) had to intervene, and plant employees had to be evacuated. The delivery zone was isolated (sewers were clogged, the plug gate on the containment pond was closed). A sand dam served to channel the neutralised HCl (with CaCO3 in powder form and liquid NaOH added). The area was cleaned, liquid wastes were neutralised and collected by an outside firm. A supply system using level difference replaced the pump, the valves were removed on 2 retention basins, and the inspection visit schedule was modified.