Environmental Impact

Marine Resources and Environment

Prof. Andrea Koschinsky

CONSTRUCTOR UNIVERSITY

Marine minerals - future resources for critical metals?

Problems:

Increasing metal scarcity endangers high-tech development and climate goals
Terrestrial metal mining creates environmental and social problems

Research questions and projects:

Marine resource potential of critical metals for the future
Environmental consequences of deep-sea mining (metal release and toxicity), field and lab tests
Method development for selective metal extraction
Sustainability of deep-sea mining
Transdisciplinary approaches (collab. with social sciences)

Can mining of marine minerals be sustainable?

Mining (land and sea) can never be sustainable in a strong sense.
Marine mining could contribute to future technologies in the sense of a weak interpretation of sustainability.

Overview of marine mineral deposits, mining methods and impacts. Positive and negative impacts are shown in green and red, respectively. (from Heinrich and Koschinsky, 2022, DOI:10.3390/books978-3-03897-877-0)

Chances of marine mineral resources

Social, political and environmental aspects

No people, including indigenous populations in remote areas, are impacted by mining and its consequences.
No or little overburden has to be removed, which can be up to 75% of moved material when mining on land.
Only mobile mining infrastructure, re-usable
Reducing dependence on raw materials from certain countries
Deep-sea mining could lower the pressure on sensitive ecosystems on land, because land mining moves further into remote areas.

Research need to ensure sustainable development of marine minerals mining

Environment

Further inventory of the status-quo of seafloor ecosystems (habitat, physical and biogeochemical conditions)
Can marine ecosystems recover from deep-sea mining? Under which conditions, at what time scales?
Potential synergistic effects of deep-sea mining and climate change, pollution and overexploitation
Monitoring and predictions of possible impacts on the environment, including pilot mining tests
Definition of threshold values for environmental standards
→ Best Practice Handbook

Baseline

determine conditions prior to mining operations
requires understanding of natural temporal + spatial variability

Monitoring

assess changes resulting from operation (and other changes)
regularly repeated

Environmental Impact Assessment
Environmental Management and Monitoring Plans

Outlook to Environmental Impact and Monitoring in the Red Sea

Large database available from previous cruises, projects, reports and publications related to metalliferous deposits in the Red Sea (e.g., MESEDA project)
New baseline studies required which include data for new critical metals previously not considered
Definition of critical threshold values and environmental guidelines
Identification of key species and parameters that are representative of the health of the ecosystem
Consideration of ongoing environmental changes due to anthropogenic activities and climate change
Ecosystem of the brines and metalliferous mud areas confined to microbial life, but ecosystems beyond are very unique with high degree of endemism.
Part of the knowledge gained in more recent environmental impact studies, e.g. from the Mining Impact project on ferromanganese nodule mining, may be applicable to the Red Sea
Most relevant environmental impact probably from sediment plume
Toxic metal release may occur when sulfidic minerals reach the oxic water column above the brines
Discharge of sediment and tailings should be avoided specifically in the photic surface layer -> preferentially below 1000 m depth

Conclusion on Environmental Impact and Monitoring in the Red Sea

Due to its uniqueness, the Red Sea ecosystem deserves a precautionary approach of deep-sea mining with ultimate care to minimize the potential harm.
Special geological and environmental situation in the Red Sea offers unique chances (high resource potential, proximity between deposits and ports, etc.)
Holistic consideration of future deep-sea mining operations desirable, especially in the light of the global biodiversity crisis, climate change and the need for sustainable development!