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Seabed mineral resources have relatively low TREO contents, low TREO grades, and significant TREO yields compared to the large terrestrial LREE-rich carbonatite-hosted deposits but are comparable to the terrestrial HREE-rich ion-adsorption clay deposits [92]. One of the issues preventing the start of REE projects in the EU concerns the possible impacts on the environment. Localities with similar deposits are found in Brazil (Serra Verde project) and Madagascar (Tantalus project) [18]. Earth Environ. Nodules that acquire metals from both sources (mixed type) are the most common and include the well-known CCZ nodules [33]. A. Ardron, A. Colao, J. M. Durden. Ecological impacts comprise mainly alteration of habitat and benthic communities, sediment disturbance and plume discharges, release of toxic compounds, light and noise generation, thermal pollution, air emissions, etc. Deep-Sea Res. 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Deposits in agpaitic nepheline syenites are commonly characterized by low Th and U contents. Often, these fears arise because marine mining may directly interfere with their business such as fishing or tourism. They may contain various chemicals, such as biocide antifouling agents, corrosion inhibitors, etc. The socio-economic impacts of deep-sea mining will mainly occur at the end of the value chain where mineral resources will be processed on land and where they may have an influence on the price development of the global metal market. 5). Artificial light emissions will occur from seabed mineral collectors supplied with strong lights that allow for camera control of the mining operations, as well as from ROVs used for monitoring the mining process. Rep. 8, 8 (2018), https://doi.org/10.1038/s41598-018-23948-5.Search in Google Scholar, [47] H. R. Kudrass. 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All relevant stakeholders including the religious and traditional leaders participated in a long-term information process, which led to the development of a national Marine Mining Act that involves both environmental aspects and local sharing of future profits. Rev. At Strange Lake deposit (in Canada), the TREO content was estimated to be 0.97 to 1.16 %, the TREO grade was 0.09 %, the ore tonnage was 492million tonnes, the contained TREO was 443kilotonnes, and the total basket price was 25.75USD/kg. It was estimated that the ore tonnage is 188106tonnes and the TREO yield is 230103tonnes. The most obvious impact of mining on benthic fauna is the uptake of REE deposits because it encompasses the disturbance and removal of their habitat. B. Jones, L. A. Levin, H. J. Niner, L. Pendleton, C. R. Smith, T. Thiele, L. Pendleton, P. J. Turner, L. Watling, P. P. E. Weaver. Therefore, and because of the open and transparent process, the majority of the local communities support a possible marine mining in the Cook Islands EEZ. It is a joint contribution of 12 national Geological Survey Organizations and Marine Institutes from 8 European countries, the USA, and Russia. The iron ore producer LKAB in Sweden and the fertilizer producer Yara in Norway are currently developing processes to start REE production operations using their apatite-rich byproducts and mining wastes. Oceans, 2, 351 (2021), https://doi.org/10.3390/oceans2020021.Search in Google Scholar, [63] J. R. Hein, A. Koschinsky, T. Kuhn. Deep-sea muds enriched in REE have been recently discovered in the eastern South Pacific and the North Pacific Ocean [30]. 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