Subsea mining; technological and regulatory challenges

As the world continues its transition to a low carbon economy, demand is increasing for metals required for new forms of electrically powered transportation and electrical storage. These metals primarily include copper, cobalt, nickel, and manganese. And while these exist on land, they are increasingly difficult to extract in an ethically sourced manner with minimal effect on the environment and human labour. Tens of thousands of square kilometres of forests are cleared every year to access metal ores, leading to habitat destruction and biodiversity loss.

Subsea mining of these minerals can be done effectively and sustainably, with a minimal impact to the environment and people at the mining site.

There are essentially three types of target areas for subsea mining, each area requires a different method of mining, and each contains a different type and proportion of target minerals.

The first type is seafloor massive sulfide deposits (SMS). These deposits are formed by extinct seafloor volcanos and are located in relatively shallow water, approximately 1000 – 2000 m. Mining of SMS is challenging because it may require cutting of ores into small pieces in a high hydrostatic pressure environment.

The second target area is known as polymetallic crusts. These are also found in the relatively shallow water of national economic exclusion zones (EEZ). Target minerals are cobalt, nickel and manganese, which are the most needed metals for electric storage batteries.

The third and final target is polymetallic nodules. These are of great interest because these nodules are sometimes called ‘battery in a box’. About 99% of the total nodule is made up of metals which are needed for batteries. These nodules exist in ultradeep water of 3000 – 5000 m and sit on the seabed, they do not require ore crushing or any removal of a cover in order to extract them.

The areas with the most concentration of minerals are found in the mid-Pacific. Specifically, in one area, the Clarion Clipper Zone (CCZ), the minable areas contain enough minerals to create enough batteries for 200 million electric vehicles. Other ocean areas including Indian Ocean and even the Red sea have had exploration on going for these vital minerals.

For simplicity sake, all subsea mining ventures will take place in either one of two areas, those are: within one coastal state’s EEZ, or in what is known as the International Area. This geographic fact will have the largest influence on the regulatory regime facing the mining venture. Some coastal states have already published their subsea mining regulations. The pattern here is very familiar to those of us with an offshore oil and gas background, because Coastal State authority is the same concept for subsea mining within an EEZ. As with Oil and Gas developments within EEZs, International Classification Societies with offshore capability are often recognised by the Coastal State authority to verify compliance with safety and environmental regulations by the mineral contractor. It is most likely that Subsea mining will follow this format. Now for those areas not in EEZs such as the previously mentioned Clarion Clipper Zone, the United Nations International Seabed Authority will be the regulator. Similar to other UN organisations such as the International Maritime Organization (IMO) the ISA will have authority over the mining operations of those sponsoring states who are signatories of the International Law of the Sea Treaty. As with the IMO, most likely the ISA will recognise certain Class Societies as organisations capable of verifying compliance with the soon to be promulgated Mining Code. This would then give the sponsoring states the authority to recognise ABS to ensure compliance with the code in all aspects. Again, this would mirror the current regulatory environment for such international conventions as Safety of Life at Sea (SOLAS) and Prevention of Marine Pollution from Ships (MARPOL).

Recent developments

In partnership with The Metals Company, Allseas is developing a pioneering project entirely to their own, unique specifications, including a wholly self-designed subsea vertical transport system, a subsea collection vehicle, and a surface nodule handling and storage system. Allseas’ 228 m Hidden Gem is being equipped with a deep-sea mineral collection system to recover polymetallic nodules from the ocean floor and transfer them to the surface for transportation to shore. The nodules contain high grades of nickel, manganese, copper, and cobalt – key metals required for building electric vehicle batteries and renewable energy technologies. The vessel will become the first to be classed as a subsea mining vessel by ABS.

A pioneering deep-sea mining system Approval in Principle (AIP) was recently awarded to China Merchants Industry (CMI) The AIP follows ABS awarding AIP for CMI’s deep-sea mining system design. The riser and lifting system designed by CMI is a key aspect of the deep-sea mineral extraction system, handling ore-seawater slurry and transporting it to the surface vessel. Additional work involved CMI’s design focus on retrieving cobalt-rich ferromanganese crust deposits attached to seamounts. It included the development of subsea mining machines and offshore mining support vessels.

Earlier this year ABS marked another industry first with a design review of Oil States Industries’ Merlin™ Deepsea Riser System, which is capable of reaching more than 6000 m beneath the waves. It is designed to collect polymetallic nodules 6000 m below the surface of the Pacific. It is the first time a deep sea mineral riser has undergone design review by a Classification organisation. ABS is supporting the company on the next phase of their project, which is the construction and certification of the riser. This technology opens up a new frontier in deep sea mineral extraction, capable of operating in harsh conditions and at extreme depths.

Demand for resources to support the low carbon economy means sustainable subsea mining will increasingly be viewed as a key technology. ABS class is providing the foundational expertise for this new industries participants. This technology is increasingly key to securing the minerals utilised in electric vehicle batteries, solar panels, and other systems which enable the energy transition, and ABS is committed to supporting its safe adoption.

_{Andrew Lipman, Director, Subsea and Mining Operations, ABS (China) Ltd.}

Read the article online at: https://www.globalminingreview.com/mining/25102021/subsea-mining-technological-and-regulatory-challenges/