On a Saturday, barium carbonate leaked from a connection point located on the return pipe of a circulation loop in an earthenware manufacturing plant. The carbonate spilled onto the ground. It was driven by heavy rain towards the plant’s rainwater system. A witness observed it pouring into the stream flowing into the River THORE at around 6.30 p.m. Overall, a quantity of 5t of barium carbonate was released. Part of the product that remained in the plant’s enclosure was pumped off and cleaned from the following Monday. Regular inspections of the appearance of the plant outlet, the gutter in front of the plant, the stream and the river were organised to check their appearance.

The economic loss directly due to the loss of product was €4,000. The cost of sub-contracted cleaning was estimated to be €3,000 and the 1.5-day production shutdown following the barium carbonate shortage €22,500. The barium carbonate tank was refilled 5 days after the incident.

The cause of the event was a valve that was open. The operator identified two possible hypotheses:

• ill will and deliberate opening of this valve by an intruder;
• valve opened accidentally a few weeks earlier, but a plug formed by the product – which has a strong tendency to plug – prevented an immediate leak. Over time, the plug was removed following either potential water hammers in the system or ageing. The barium carbonate then exited via this connection point as the valve was open.

Following the event, the operator identified all the plant’s other liquid substance systems featuring a circulation loop and put in place glued stoppers that can only be removed using tools on all connection points to the outside without a retention area. The plant was patrolled by staff at the weekend at least twice a shift. Under the valve that caused the incident, a funnel recovering product in the event of a leak was put in place with a pipe connected to a retention tank located under the barium carbonate tank 15m from this valve.