By Nguyen Truong Giang
In July 2021, Nauru triggered the “two-year rule” under the UN Convention on the Law of the Sea (UNCLOS). This little-used provision forced the International Seabed Authority (ISA) to complete its Mining Code for deep-sea extraction within two years. The deadline expired in mid‑2023 without a finished rulebook, legally allowing commercial mining to start in international waters without finalized environmental safeguards.
Two years later, at its 30th session in Kingston, Jamaica in July 2025, the ISA once again came under intense pressure to finish the Mining Code. Some member states and contractors pushed to move ahead with operations, raising the need for critical minerals to fuel the global energy transition. Environmental groups, including the Deep Sea Conservation Coalition, warned that fragile ecosystems could be irreversibly damaged. Despite weeks of debate, no agreement was reached to halt deep-sea mining. The absence of binding rules leaves the door open for unilateral moves.
Why the South China Sea should care
The ISA’s authority covers “The Area”—seabed beyond national jurisdiction. At first glance, that might seem distant from the South China Sea (SCS). But in practice, boundaries in the SCS are a patchwork of overlapping exclusive economic zones (EEZs), disputed features, and potential extended continental shelves. If valuable deposits of polymetallic nodules or cobalt-rich crusts are found in contested areas, the region could face the same legal and political uncertainties now seen in the Pacific.
China’s state-owned enterprises already hold multiple ISA exploration contracts in the Clarion-Clipperton Zone, gaining technical capacity that could be applied closer to home. The Philippines’ Benham Rise victory in extending its continental shelf shows how UNCLOS mechanisms can work, but such outcomes are far harder when sovereignty is contested.
Environmental stakes
Deep-sea mining is not just about economics; it is also an environmental gamble. Scientific research warns that sediment plumes from mining could smother marine life, disrupt carbon cycling, and cause biodiversity loss on a scale that may be irreversible.
These are not abstract concerns. In April 2025, tensions spiked at Scarborough Shoal over “dangerous maneuvers” between Chinese and Philippine vessels. On 7 June 2025, a Chinese maritime militia vessel grounded at Pag-asa Reef 1 and, while freeing itself, its anchoring activity caused significant damage to surrounding coral. Manila is now weighing a second international case against Beijing for environmental damage. These incidents illustrate how resource exploitation and environmental harm can quickly escalate into diplomatic and security crises.
The counter‑argument: economic and strategic needs
Proponents of deep-sea mining argue that it offers access to essential minerals for electric vehicles, wind turbines, and other clean-energy technologies. They note that land-based mining often causes severe social and environmental harm, and that seabed extraction, if properly regulated, could be less damaging overall. For states with limited land resources but vast maritime zones, like many in ASEAN, deep-sea mining represents a rare economic opportunity.
Some industry advocates also claim that delaying mining risks allowing a few technologically advanced states to dominate the sector, leaving others behind. In this view, waiting for a “perfect” regulatory framework could mean missing the window to benefit from the energy transition.
Why this is risky for the SCS
The problem is that the SCS has neither a unified environmental standard nor a binding code for seabed mining. Governance is fragmented: national laws vary, and there is no regional body with authority over disputed areas. If one claimant begins mining unilaterally, others may feel compelled to follow suit to avoid losing out, creating a “race to the seabed.”
Moreover, the SCS is already one of the world’s most militarized maritime zones. Any industrial activity in contested waters risks being viewed through a security lens, increasing the chance of confrontation. This is especially true when civilian vessels are backed by coast guards or maritime militia, as seen in recent confrontations.
Bridging the governance gap
The lesson from Nauru’s two-year rule and the ISA’s slow progress is clear: set the rules before the drills arrive. For the SCS, that means acting before any significant exploration or extraction begins. ASEAN and dialogue partners could develop a South China Sea Seabed Resources Code. This would:
- Require transparent environmental impact assessments.
- Define permissible activities in disputed and non-disputed areas.
- Establish dispute settlement mechanisms consistent with UNCLOS.
Such a code would not resolve sovereignty disputes, but it could create shared expectations that reduce the risk of environmental harm and escalation.
Looking ahead
Some may argue that the ISA’s eventual Mining Code will be enough. But the Pacific experience shows that global rules often lack the specificity and enforcement mechanisms needed in complex regional disputes. The SCS has a narrow window to learn from this and craft its own safeguards.
The question of “who owns the deep” is really about who takes responsibility for managing it wisely. In the SCS, failing to act now could mean watching the last frontier of the ocean turn from a shared heritage into a contested battleground, both environmentally and strategically.
Nguyen Truong Giang is a Vietnamese researcher specializing in international environmental governance and maritime security. He holds a BA in International Economics from Foreign Trade University (Vietnam) and an MSc in International Relations from Ritsumeikan Asia Pacific University (Japan), where he was an Asian Development Bank-Japan Scholarship Program (ADB–JSP) scholar. His work focuses on linking climate policy, resource governance, and conflict prevention in contested seas, with a particular interest in the South China Sea.
