At around 12:00 p.m., the oil drain hose of a case-hardening furnace slipped out of a container being filled during the performance of special maintenance work at a mechanical components factory. By the time the technicians noticed it, 50 l of oil had spilt onto the asphalt and the grass. The technicians stopped any further spillage. They then placed spill-absorbent socks around the puddle and spread granules over it. At around 3:00 p.m., a specialist firm cleaned the asphalt and dug up a 2-cm-thick layer of polluted soil (the frozen ground prevent the oil from penetrating any further). The waste was sent away to be treated.

The furnaces at the factory are only emptied once every five years. The equipment used was not appropriate for the task: the overly short hose limited the number of places where the work could be performed, the low pump flow rate led to longer container filling times, and the chosen location was unsuitable. The technicians in charge of the job were not accustomed to performing this type of work and had no operating procedure to refer to. In addition, they could not continuously monitor the operation because they had other tasks to do at the same time and the temperature of –11° C did not encourage them to stay outside for long. The oil-filled hose was slippery and stiff.

To prevent any recurrence of the same type of accident, the operator plans to hire a specialist firm to carry out this special maintenance work and to pump the used oil directly into a lorry instead of into containers.