At about 0035 on 1 June 2018, the YM Efficiency, a container ship en-route to Sydney, lost 81 containers overboard, with a further 62 damaged. The ship also sustained structural damage to its lashing bridges, superstructure and accommodation ladder. Following the incident, substantial amounts of debris released from the containers washed ashore on the central coast of NSW. A protracted clean-up operation collected over 1000 m3 of material.
Of the 81 containers lost overboard, five stranded on the coastline and a further 60 were located on the seabed (see case study ‘Using remote drones to locate debris from the YM Efficiency’ in the 2018–19 annual report for how AMSA located the containers). The removal of the containers was in the long-term interests of the community and fishing industry, as they posed unacceptable environmental and safety risks. Widespread coastline pollution has the potential to cause loss of amenity for the community and a reduction of life quality for people using these areas and containers on the sea bed increased safety risks from hook ups with fishing gear.
The main environmental hazard associated with the containers and their contents was plastic. Much of the cargo content was made of a wide range of plastic, as was the wrapping and packaging. Micro plastics are a particularly persistent and pervasive pollution problem in world oceans. Plastics leach and accumulate toxins, choke and disable animals, and create opportunities for biosecurity incursions.
AMSA contracted Ardent Oceania in December 2019 to recover the 60 containers on the seafloor. For the work to be conducted safely and to minimise further environmental damage, a subsea basket was designed by Ardent and produced in Newcastle. Supported by remotely operated vessels, the basket eliminated the requirement to lift the containers directly.
The MV Pride, a 130 metre vessel with a 250 tonne heave compensated crane, docked in Newcastle Port on 3 April 2020 to begin the container recovery with the loading of the subsea basket, Australian seafarers, project staff and equipment. On 6 April, the MV Pride deployed the subsea basket for the first container recovery. An additional three containers were located and recovered during the operation, and the final container was recovered at 0940 on 8 May 2020. A total of 63 containers were removed over 34 days.
Avcon Projects Australasia (a NSW Environmental Protection Agency-licensed company) managed the processing and disposal of the recovered pollution/waste. The materials were segregated for reuse or recycling, with only the residue going to landfill. Waste management was completed on 11 May 2020. The operation was highly successful with more than 700 tonnes of potential pollution removed from the marine environment.