At about 6 a.m., a fire broke out in the fermentation/maturation zone of a green waste composting and wood shredding centre. Firefighters used construction machinery to move green waste and sprayed it down with water to stop combustion. The 30 t of waste involved in the fire was reintegrated into the composting process.

The operator had not complied with the requirements of the prefectoral decree concerning the storage height of compost windrows (8 m as opposed to 2.5 m authorised). All of the compost had been grouped together on part of the platform in preparation for shipment to agricultural customers. In addition, the windrow temperature measurements required by the prefectoral decree had not been conducted on the day of the accident, and these checks were not formally monitored.

According to the operator, the weather conditions (cold, strong wind) would have favoured a shift in the fermentation of the waste. The cold weather, confronted with the heat of fermentation, would have resulted in a thermal shock resulting in activation energy. The wind would have kept the smouldering fire going.

Following the accident, the operator was issued formal notice:

• comply with the compost storage heights;
• comply with the requirements in terms of compost management by production batches (separation of manufactured batches using uniform production parameters, conducting temperature measurements in batches).

The operator must also install a 500 m³ flexible tank to ensure sufficient water reserves in the event of a fire.

The operator also plans to conduct fire drills with the fire brigade.

A new outbreak of fire occurred on the site 2 months later (ARIA 48018).