Seabed mining environmental study underway [1]
Monday, February 22, 2021 - 19:18. Updated on Tuesday, February 23, 2021 - 09:27.
By Eleanor Gee
An environmental study on seabed mining for polymetallic nodules or rocks that contain metals needed to build batteries, is underway in the Clarion Clipperton Zone (CCZ) of the Pacific between Hawaii and Mexico.
The study is being undertaken by DeepGreen Metals Inc., a Canadian-based seafloor mining developer, which acquired Tonga Offshore Mining Limited (TOML) last year.
As the world starts to transition from using fossil fuel to cleaner energy, DeepGreen aims to use the metals (nickel, copper, cobalt and manganese) found in polymetallic rocks, to power electric cars. The CCZ contains “enough metal to electrify the entire global car fleet of 1.3 billion cars several times over”.
DeepGreen Tonga Offshore Mining Limited (TOML) Country Manager, Christina Pome’e said the environmental work currently underway is being conducted in the NORI area of the CCZ which is sponsored by Nauru, but all the learnings and the same approach will be applied to the TOML area very soon. TOML work that will start this year will include resource information and some environmental work.
She said the environmental study is their main focus, which should be completed in the next three years. They are looking at how removing these rocks from the seabed will impact organisms and the surrounding marine environment.
Christina is the only female Marine Geo Scientist in Tonga and has worked in the CCZ, collecting samples and taking photos of the area.
"The seafloor is like a desert and all you can see are these rocks laying unattached on the seafloor."
And there is no drilling or excavating activities involved in their work.
She said judging from the photos collected from the seafloor so far, the biomas in the area is low.
“I had a team here logging photos after identifying organisms. So, they would go through four or five photos before they found an organism.”
“The normal organisms we see here in our water (Tonga’s EEZ) we do not really get that there. So, we’re only talking about really small types of organisms. But we still need to make sure that there is a more sustainable way of how to get these rocks up and not affect the environment.”
How are Polymetallic Nodules formed?
Polymetallic nodules or rocks are formed naturally by sediment and minerals in the ocean.
“Minerals in the ocean come predominantly from land (the Rockies in North America and the Andes in South America. Sometimes when organisms die on the surface, it takes time for them to sink. They decompose and minerals are released from their bodies and it stays in the ocean water, and they live there. When these minerals find a solid object, such as a whale’s tooth, they start to attach to it and slowly form a rock,” said Christina.
“It’s like mother nature made the rocks for this time, when we’re struggling with climate change.”
Christina said there are different types of mineral deposits (rocks) across the world’s seafloor.
“Here in Tonga there are different mineral deposits, called seafloor massive sulphide (SMS). SMS are from the hydrothermal vents, totally different from polymetallic nodules.”
Polymetallic rocks do not contain any toxic element and are almost 100% usable, said Christina.
She said DeepGreen will be looking at recycling the four metals in the rock and also recycling the remaining metals.
“There is no solid waste when processed unlike land based mining. To get these four basic metals on land, you need to mine four different land sites.”
Tonga
The Tonga Government is sponsoring TOML to be able to undertake seabed exploration under DeepGreen, and will receive royalties from every nodule taken from the TOML contract areas within the CCZ.
Christina said that while anyone can apply for a licence, underdeveloped states like Tonga do not have the resources or the money to do so.
“So, the only way Tonga can participate is through a private contractor (Deep Green) and we can benefit from it.”
Public relations partnerships
Meanwhile, DeepGreen is supporting Tonga's communities. It has given out funding for various projects in communities as well as scholarships to encourage students to take up science.
“We have very few people working in my area and it is very important to educate more people in this field because it’s no use if we have more job opportunities in the future but we don’t have the capacity. And our people don’t have the knowledge and experience and the skills. The only way is to educate our kids.”
“It’s a huge opportunity for Tonga and also there’s a lot of people concerned about the environment and we do value the environment and that’s part of our job,” she said.
DeepGreen also has similar partnerships with Nauru and Kiribati.
Related article: https://matangitonga.to/2020/04/23/deepgreen-metals-takes-over-tonga-offshore-mining [2]