Maritime Chemical Accident

Off the coast, 60 n.m. west of Ijmuiden, The Netherlands

Acrylonitrile (Class 3, 6) in tank containers; flammable liquid, toxic to both human and marine life, TLV 2 ppm (USA), IDLH 85 ppm (USA); marine pollutant

Summary:   On May 27 ,1988, the Dutch chemical carrier Anna Broere, on her way from Rotterdam to England, collided with the Swedish container ship Atlantic Compass. Atlantic Compass could continue its journey towards Antwerp while Anna Broere was severely damaged and sank in the shallow water. The cargo of Anna Broere consisted of 547 tonnes of acrylonitrile and 500 tonnes of dodecyl benzene, of which the latter is not regarded as a marine pollutant and was therefore left untreated. Acrylonitrile however is a very dangerous chemical, both to humans and as a marine pollutant. An exclusion zone with a radius of 10 km and a height of 300 m was therefore set up. Dutch authorities started an operation in order to recover the acrylonitrile with the help of a large floating crane. First the wreck was sawed in half so that the stern could be lifted separate from the leaking cargo tanks. Both parts of the ship were eventually lifted and about half of the acrylonitrile was recovered. The other half had leaked out and rather quickly dispersed into the sea. During the operation the concentrations of acrylonitrile in air and water was continuously monitored due to the safety of the personnel. Because of hard weather the operation was delayed several times. The operation lasted a total of 73 days, but only in 25 of those days salvage work could be carried out.

Cause of Accident:   A collision with another ship caused severe damage to the hull and caused the ship to sink.

Comments on Response:   The response operation was done properly and correct. The costs came to be much greater than expected, but this was mostly due to the bad weather conditions. It can be discussed however if the calculated impacts on the environment would have been that severe. The 200 tonnes of acrylonitrile that leaked out did cause damage to the marine biota, but not at all as much as it was believed. As the concentrations of the pollutant were continuously measured, no unnecessary risks were taken by the rescue personnel.

Source of Information:   Incident report on the Anna Broere, Rijkswaterstaat North Sea Directorate, The Netherlands.