UK-based subsea excavation specialist James Fisher Subsea Excavation (JFSE) has completed its first project in Taiwan.

A team from the mass/controlled flow excavation (M/CFE) provider deployed the shallow draft Twin R2000 tool to de-bury and retrench a cable for maintenance as part of the Formosa 1 wind farm development for its client, cable lay contractor Woen Jinn Harbor (WJH), Taiwan.

“The Twin R2000’s non-contact method and ability to operate in very shallow water depths was critical to the success of the excavation which was completed in just 50 hours, significantly ahead of schedule,” said JFSE.

Formosa 1, near Miaoli on the west coast of Taiwan, is a 130-megawatt wind farm and will be the country’s first commercial-scale offshore wind project. The first two turbines went live in 2017.

Lee Cheng-Yu, director at WJH, said: “This was a complex element of the project. We needed to use an M/CFE provider that had a strong track record in the offshore wind farm market so we could fully trust the cables would be protected during the process. The JFSE team and the Twin R2000 provided a fantastic service.”

JFSE said its fleet of tools provides a non-contact form of excavation that eliminates the risks associated with other excavation methods and have the additional benefit of real-time sonar imaging which enables precision excavation.

“The tools are used for applications including pipeline and cable trenching, de-burial, rock dump dispersal and seabed clearance and preparations. The M/CFE spreads are ideal for moving materials such as sand, silt and mud, drill cuttings, clay and rock dump,” the firm said.

This was JFSE’s first project in the emerging Asia Pacific renewables industry. Worldwide, it has completed more than 70 excavations at offshore wind farm sites.

UK ROV solutions provider Aleron Subsea reports it has taken part in a £145 billion salvage project in the Atlantic Ocean, utilising its AUXROV subsea system.

Aleron and the AUXROV were selected by James Fisher Marine, UK, and Britannia’s Gold Ltd, UK, to assist with a salvage operation targeting wrecks that were sunk during the First and Second World Wars.

During both wars, some 7500 merchant ships were sunk of which approximately 700 were identified as carrying shipments of gold under UK government direction.

Britannia’s Gold Ltd has been established to finance the recovery of targeted cargoes and return them to the UK for the benefit of the government, investors and merchant marine charities. This inaugural salvage work scope takes place after 25 years of planning, and the successful completion of a significant crowdfunding campaign.

The AUXROV work scope comprised more than 850 lifts, moving more than 500 tonnes of debris with three different hydraulic grabs, and providing real-time information on the grabbed materials. During simultaneous operations with two work-class ROV systems, it then provided power and assistance in dredging operations on the wreck. Remaining in the water for up to 90 hours at certain stages, the AUXROV was able to enter several constrained, hard to reach areas of the site assisting in the overall efficiency of the operation.

Aleron Subsea technical director Mike Bisset said: “This was a complex working environment within which the AUXROV has been able to demonstrate its value and efficiency.”