5.6 Issues associated with CCS offshore

The United Nations Convention on the Law of the Sea 1982 (UNCLOS) is largely a codification of the customary international law of the use of the seas.

Relevantly, UNCLOS separates the sea into a number of jurisdictional zones. Issues associated with different zones are highlighted below.

5.6.1 Territorial sea

Each coastal State may claim a territorial sea that extends seaward up to 12 nautical miles from its baselines (Article 2 and 3 of UNCLOS). This sovereignty over the territorial sea extends to the air space above it, and the sea bed and subsoil beneath it (Article 2, UNCLOS). As such, the domestic laws and consequent consents and authorisations of each coastal State will be required for the undertaking of CCS activities in each territorial sea.

5.6.2 Continental shelf

A coastal State has exclusive sovereign rights over its continental shelf for the purposes of exploration and exploitation of its natural resources. Arguably geological formations under the sea bed are a non-living resource of the sea bed and subsoil and as such, the express consent of the coastal State will be required to undertake CCS activities such as injection and storage.

All States are entitled to lay submarine cables and pipelines on the continental shelf. In relation to CCS, this gives other States a relatively wide discretion to lay pipelines to transport CO2 over the continental shelf of another. However, coastal States have the exclusive right to authorise and regulate drilling on the continental shelf for all purposes (Article 81, UNCLOS). As such, a coastal State will be able to control injection and storage activities on the continental shelf to the extent that such CCS activities involve drilling.

5.6.3 Exclusive economic zone

Each coastal State may claim an exclusive economic zone (EEZ) beyond and adjacent to its territorial sea up to 200 nautical miles from which the breadth of the territorial sea is measured (Article 57, UNCLOS), although in many situations, States will not be able to claim the full 200 nautical miles due to an adjacent State.

To the extent that the continental shelf and the EEZ cover the same area, a State’s right to lay pipelines and conduct other CCS activities such as drilling in the EEZ will largely be the same as discussed above in relation to the continental shelf.

5.6.4 Offshore areas beyond national jurisdiction

Under international law, the global commons have a special status and are treated as the common heritage of mankind. As such, these areas are vested in the international community as a whole, with no State or person being able to appropriate territory within them, and which are to be preserved and to be freely available for use for the benefit of present and future generations. The key barriers to CCS in the global commons relate to the ability to undertake offshore CCS activities in the high seas, and in particular, in the sea bed and ocean floor and subsoil beyond the limits of national jurisdictions.

5.6.5 High seas

The high seas are defined in UNCLOS as being all parts that are not under national jurisdiction. Importantly the definition of the high sea refers to the water column and not to the sea bed, ocean floor and subsoil underlying high seas.

States enjoy six freedoms within the high seas, being:

  • freedom of navigation;
  • freedom of over flight;
  • freedom to lay submarine cables and pipelines, subject to Part VI;
  • freedom to construct artificial islands and other installations permitted under international law, subject to Part VI;
  • freedom of fishing, subject to the conditions laid down in section 2; and
  • freedom of scientific research, subject to Parts VI and XIII.

These freedoms are to be exercised by all States with due regard for the interests of other States and also with due regard for the rights under this Convention with respect to activities in the Area.

Transport of CO2 in the high seas

The freedom to lay cables and pipelines and the freedom of scientific research are relevant to CCS activities. Unlike the laying of pipelines in the continental shelf, there is no requirement under UNCLOS to obtain the consent of any particular State to conduct such activities in the high seas. Whilst general notification provisions and obligations not to cause environmental harm apply, States nevertheless have a wide discretion to lay such pipelines.

Storage in the water column in the high seas

In relation to storage of CO2 in the water column in the high seas, the Convention for the Protection of the Marine Environment of the North-East Atlantic (OSPAR Convention) which relates to the North Atlantic was amended in 2007 to specifically prohibit storage of CO2 in the water column. The London Protocol (discussed below) was also amended to allow storage in geological formations in the sea bed (but not the sea column).

Further, storage in the water column must be considered in light of the general provisions of UNCLOS regarding pollution and harmful changes to the marine environment including waste dumping. In practice, these provisions all serve to limit the ability to undertake storage in the water column in the high seas.

Liability in high seas

Where activities are undertaken in the high seas, such as the transport by pipeline, under Article 114 of UNCLOS, every State shall adopt the laws and regulations necessary to provide that, if persons subject to its jurisdiction who are the owners of a submarine cable or pipeline beneath the high seas, in laying or repairing that cable or pipeline, cause a break in or injury to another cable or pipeline, they must bear the cost of the repairs. If pipes are damaged by a vessel of another State, the jurisdiction of the vessel (and consequent liability) is determined by the flag State of the offending vessel. However, this can be problematic as the vessel may be flagged in a State with an open registry (ie a ”flag of convenience”) undermining enforcement action.

5.6.6 The Area

The sea bed, ocean floor and subsoil beyond the limits of national jurisdiction form a different geographic zone under UNCLOS defined as the ”Area”. The provisions relating to the Area are directly relevant to the injection and storage of CO2 in the sea bed.

As the global commons, the Area and its resources are regarded as ”the common heritage of mankind”, and no State may claim or exercise sovereignty or sovereign rights over any part of the Area or its resources (UNCLOS Article 1(1) and Part XI).

Whilst it is arguable that exploration and research may take place in the Area on a temporary basis, States are not able to assert sovereignty over the Area through the permanent occupation of its Territory (including geological storage spaces). This framework may limit the ability to explore for sub-sea bed geological storage sites and, more importantly, prevents the injection of CO2 into the Area by a State or States, and its permanent storage for the benefit of the State or States.

For CCS injection and storage to be permissible in the Area, amendments would be required to be made to UNCLOS in accordance with the amendment and ratification procedures described above. In addition, the International Seabed Authority would need to be given the ability to regulate and set standards in relation to CCS activities, extending its jurisdiction to regulate exploration related to matters other than mineral resources. No information is currently available suggesting any intention to draft amendments to UNCLOS to clarify the ability to undertake CCS activities in the Area. Similarly, there are no signs of there being any international will to allow such activities to take place in the Area.

There should be an immediate completion of reviews, and if necessary, amendments to international agreements, including the definitions of ”waste” under the London Protocol and ”hazardous waste” under the Basel Convention that currently prohibit the transboundary movement of CO2

5.6.7 Other international issues associated with CCS in the marine environment

Article 194 of UNCLOS requires States to take individually or jointly as appropriate, all necessary measures to prevent, reduce and control pollution from any source. Pollution is defined in Article 1(4) of UNCLOS. The definition of pollution is broad and the University College London Carbon Capture Legal Program notes that there is no conclusive opinion as to whether CCS would constitute pollution in accordance with this definition (UCL Carbon Capture Legal Program, 2009). This definition of pollution may limit the ability to store CO2 in the sea column and is also relevant to whether CO2 that seeps from a geological formation will be regarded as pollution. The London Protocol prohibits the dumping of any wastes or other matter with the exception of those listed in an Annex to the Protocol (London Protocol, Article 4 and Annex 1). The London Protocol was recently amended in 2007 to make clear that CO2 could be stored in the sea bed with a permit. The amendment does not extend to the water column.

Despite the amendments to the London Protocol and OSPAR Convention, which can be seen as a positive move towards offshore CCS activities, there remain barriers to the transboundary export of CO2, which is currently prohibited under Article 6 of the London Protocol.