Summary:
On February 1, 1991, the chemical carrier Alessandro Primo sank in
the Adriatic Sea 16 miles off the coast of Italy. The water depth was
110 m and aboard the ship was a cargo of 550 tonnes of acrylonitrile
and 3000 tonnes of ethylene dichloride. An exclusion zone of ten
mile radius was set up around the wreck. During the following days water
samples were taken around the wreck at various depths. Four days after the
incident a trace of acrylonitrile was found 500 m from the wrecks
position. Surveillance of the wreck with the aid of a ROV also showed
evidence of an acrylonitrile leak. It was considered to be
impossible to recover the entire ship which had been severely damaged when
hitting the bottom. Diving at this depth also posed great difficulty.
Three companies specialised in the area was hired to recover the cargo
which threatened to pollute the area. The first step was to block the
leaking of acrylonitrile and this was done by February 21. By the
beginning of April the recovery operations started. With the aid of a
large pontoon and a depot ship, the tanks of Allesandro Primo were emptied
within less than a month. Many precautionary actions were taken during the
hazardous operation, such as a helicopter standing by and emergency
personnel present. Despite the difficulties and the great risks no
injuries were encountered. All of the remaining cargo was taken care of,
although most acrylonitrile had leaked out before the recovery operation
started.
Cause of Accident:
Not available.
Comments on Response:
The incident was complicated due to many different circumstances, such as
great depth and very dangerous chemicals. The handling of the situation
was successful and very professionally done. The environmental impact of
the incident was very small, especially regarding that two very pollutant
chemicals were involved.