The Magazine for Underwater Professionals
Japan has become the first nation in the world to mine a deep-sea hydrothermal vent. The country’s Ministry of Economy, Trade and Industry and the Japan Oil, Gas and Metals National Corporation (JOGMEC) confirmed last month that they had successfully carried out a mining and lift test of hydrothermal deposits at about 1600 metres depth in the ocean near Okinawa.
The success of the test, which extracted zinc, gold and other minerals, could be a major step towards establishing the technologies required for ocean mineral resource development. However, it has sparked renewed concerns among scientists about how this new “gold rush” will affect the unique creatures living off these ore deposits.
According to the Ministry of Economy, Trade and Industry, the test confirmed that there is no serious influence on the surrounding environment. “We are planning to comprehensively promote efforts towards commercialisation of submarine hydrothermal deposits by promoting economic evaluation and environmental investigation,” it said in a statement.
But Dr Stace Beaulieu, a biologist at the Woods Hole Oceanographic Institution, USA, warned of the risks. “The hydrothermal vent ecosystem may be subject to catastrophic impact from mining with a loss of habitat and associated organisms,” she said.
Beaulieu added: “These vents are significant ecologically and biologically and there is also an unknown biodiversity nearby. We have to look at the economic value of these ecosystems, the potential trade off.”
Subsea services provider Bibby Offshore, UK, reports it has completed three further contracts from Aberdeen, UK-based oil and gas operator Apache North Sea.
The multi-million pound contracts utilised Bibby Offshore’s diving support vessels Bibby Polaris and Bibby Topaz and its construction support vessel Olympic Ares.
Operating across North Sea assets during Q3 2017, the vessels engaged with project activities, which included supporting field development and inspection repair and maintenance.
Barry Macleod, UKCS managing director at Bibby Offshore, said: “Securing a triple win from Apache reinforces Bibby Offshore’s key objectives; to fully appreciate our clients’ requirements and provide them with efficient, multi-scope operations.
“We are delighted that once again Apache has trusted Bibby Offshore with this repeat business, which continues to strengthen the close working relationship we have developed.”
Mark Richardson, projects group manager at Apache, said: “Working closely with Bibby Offshore has developed a trusting, flexible and adaptable relationship, helping to maximise the safety and production efficiency of our subsea assets. The team has, once again, delivered a safely managed, very successful multi-vessel intervention.”
Tidal Transit, UK, reports it recently chartered one of its crew transfer vessels (CTV), Ginny Louise, to specialist diving company Reach Engineering and Diving Services (REDS), UK. REDS was contracted by asset management company XceCo, UK, to carry out internal inspections of 20 monopile foundations at Lynn and Inner Dowsing Offshore Wind Farm, located off the east coast of England in the Greater Wash.
The operation lasted 28 days, thanks to good weather. During the four-week long exercise, Ginny Louise sailed from Grimsby to the wind farm on a daily basis, carrying a team of seven divers from REDS plus two technicians and a site representative from XceCo.
Ed Woodrow, REDS sales and marketing director, said: “Monopile inspection is a very specialised area and not without difficulties. Our divers have to access the water inside the monopile from a height, in a confined space and in poor visibility. Subsequently, health and safety requirements are of paramount importance.”
He added: “With the growth of the offshore wind industry, 60 per cent of our business is in this sector, and this was the fifth successful contract we have undertaken for Lynn and Inner Dowsing Offshore Wind Farm in seven years. However, this is the first time we have used a Tidal Transit CTV, and our team was very impressed. The onboard facilities are fantastic, but more importantly, the Tidal Transit crew proved to be more than just that – they became part of our team, helping to do the job. I would have no hesitation in using one of Tidal Transit’s vessels in the future.”
Leo Hambro, commercial director at Tidal Transit, said: “Becoming involved in this extremely specialised exercise has proved to be interesting and fulfilling for Ginny Louise’s crew members, who are more used to transporting technicians to and from wind farm sites, both nearshore and out as far as Dogger Bank. Both they and the company are looking forward to further contracts with REDS.”
UK-based ASV Global and TerraSond of the USA have announced the completion of the first ever seabed cable route survey supported by an unmanned surface vehicle. The survey route included various water depths and strong currents, while facing difficult wind and sea conditions in the Bering Sea offshore Alaska, the companies said.
The project was mobilised immediately following a 9000-kilometre nautical charting survey by TerraSond, of which 4750 kilometres (53%) was executed by an ASV Global C-Worker 5 autonomous surface vehicle. The cable route survey required a new payload including a hull-mounted multibeam sonar, a sub-bottom profiler and a towed sidescan sonar with 250 metres of armoured sonar cable. The payload swap on the C-Worker 5 was integrated, calibrated and demonstrated in the field in less than 48 hours, according to ASV Global. A total of 1220 kilometres of cable route survey lines were then successfully executed by the C-Worker 5 system, the company added.
Thomas Chance, chief executive officer of ASV Global, said: “This is a landmark achievement for ASV technology, and we are pleased to be supporting TerraSond in this effort. The fast re-tasking of the system from one type of mission to another illustrates the flexibility of the C-Worker ASV, and its consistent performance in difficult sea conditions further underscores the value of this highly efficient approach to offshore operations.”
Throughout the operation the C-Worker 5, designed for up to five days endurance at survey speeds of up to seven knots, was remotely monitored using ASV Global’s ASView control system from a station on TerraSond’s mother ship.
ASV Global has supported TerraSond for three consecutive years refining the use of autonomous systems in hydrographic survey applications. This year’s deployments follow on from a 2016 charting survey completed in the Bering Sea, off Alaska, where ASV Global and TerraSond marked an industry first by completing a 9578-kilometre hydrographic survey, 4213 kilometres of which were completed unmanned. Combined, these operations result in more than 10,000 kilometres in unmanned survey lines.
Tom Newman, president of TerraSond, said: “We continue to be impressed after several projects with ASV’s C-Worker 5 in a variety of missions. Together with ASV we have performed the first use in charting, first use in the Arctic, first use for a cable route survey and first to accumulate more than 10,000 kilometres in use. ASV’s team has risen to each challenge and the system has proved to be a reliable and cost-effective force multiplier, often doubling our production, operating in areas unsafe for a larger vessel and allowing multitasking on projects.”