Perspectives of Geological CO₂ Storage in South Korea to Cope with Climate Change

Rapid industrialization and urbanization in the 20th century have led to increasing volumes of carbon dioxide being released into the atmosphere, resulting in global environmental problems, such as climate change [1,2] (pp. 275–290, 1265–1274). Recognizing the seriousness of climate change caused by greenhouse gases, countries around the world adopted the Kyoto Protocol in 1997 in a pledge to reduce carbon dioxide emissions. The Kyoto Protocol focuses on the regulation of carbon dioxide emissions, which is the main cause of global warming, and sets emission reduction targets for each signatory country. According to the Organization for Economic Cooperation and Development (OECD) report [3], South Korea’s energy consumption and CO₂ emissions intensity per capita and gross domestic product (GDP) in 2005 were near the average of OECD countries. However, South Korea accounted for 1.7% of global CO₂ emissions in 2010 and became the world’s eighth highest producer of carbon dioxide [4].

In December 2015, a new climate change treaty, the Paris Agreement, was established (Falkner 2016) [5]. This agreement is a remarkable new climate change treaty after the Kyoto Protocol in 1997 and has sparked global interest. The Kyoto Protocol imposes a greenhouse gas reduction obligation on only Annex I countries (not including the US, Japan, Canada, Russia, and New Zealand). However, the new climate regime requires both Annex I and non-Annex I countries to conduct comprehensive responses (mitigation, adaptation, financial support, technology transfer, capability reinforcement, and transparency), including greenhouse gas reductions [6,7]. South Korea has set a 37% reduction target for greenhouse gas emissions (Business As Usual (BAU)) for the year 2030 as per the Paris Agreement. To meet the greenhouse gas emission goals proposed in the Kyoto Protocol, it is necessary to develop and apply technologies applicable in the disposal of carbon dioxide, while making efforts to increase energy efficiency, use low-carbon energy sources, and develop alternative energies.

Above all, the reduction and regulation of emissions of CO₂ are fundamentally important objectives. Nevertheless, carbon dioxide capture and storage (CCS) is an internationally recognized carbon sequestration technology and is currently a promising alternative. According to the Special Report by the Intergovernmental Panel on Climate Change (IPCC) in 2005, storage technologies such as ocean storage, mineral carbonation, and geological storage can be utilized for carbon dioxide storage; however, ocean storage could disrupt marine ecosystems and mineral carbonation requires a large amount of energy for chemical reactions. In addition, the storage and treatment of carbonate minerals may cause additional environmental problems [8,9]. On the other hand, underground storage is a representative storage technology that has been extensively researched in developing countries [10,11].

CCS is an indispensable link in the transition from a society based on fossil energy to one based on future renewable energy and low carbon energy. However, the greatest uncertainty and risk in geological storage of carbon dioxide is leakage triggered by seismic events, such as volcanic eruptions and earthquakes. Leakage of CO₂ implies the risk of disturbance and destruction of ecosystems and may even lead to loss of life [12,13]. In addition, leakage of carbon dioxide injected underground may reduce the storage efficiency and threaten the existence of projects, and above all, has significant influence on the social acceptability of this technology—an essential aspect in the commercialization of CCS projects [14]. Therefore, it is imperative to evaluate the possibility of environmental impacts of carbon dioxide leaks and conduct studies to prepare countermeasures. Efficient, low cost detection of carbon dioxide leakage and prediction of the effects on water quality in advance will not only increase the acceptability of geological storage of carbon dioxide but will also enable us to proactively predict and respond to underground environmental problems. For this reason, studies on CO₂ leakage in facilities with environmental management purposes are urgently required [15,16].

In addition, South Korea considers CCS technology as the key to low-carbon green growth [17,18]. In 2010, the Green Growth Committee established the “Korean National CCS Master Action Plan” to achieve the national carbon emission reduction target. Accordingly, the foundation for the development of CCS technology aims at commercializing CCS plants and securing international technological competitiveness by 2020. Based on this, the “Korea CCS 2020” project (with the goal of finalizing and injecting carbon dioxide into a 10,000-ton underground storage in 2015), which aims for the “completion of CCS technology through establishment of CO₂ storage core elements and system technology,” and other plans for commercial storage and demonstration are being promoted. The Ministry of Environment (MOE) in South Korea has sanctioned the development of technologies to detect and manage the environmental impacts and risks associated with the storage of CO₂ in the ground. The MOE supported the CCS Environmental Management Research Group with a total of USD 19 million over a four-year period from 2014 to 2017 to develop technologies for monitoring CO₂ leaks, soil, groundwater, vegetation, and ecosystem environmental impact assessment, and has secured environmental management technology.

Nevertheless, despite this mid- to long-term CCS project pursued by the government, environmental management guidelines and regulations for environmentally safe CCS projects are still insufficient. One solution to the environmental challenges of CCS implementation would be the establishment of a publicly-accessible national CO₂ storage environment management system that provided details regarding the development, demonstration, and progress of environmental management technologies for CO₂ storage. Furthermore, it is vital to prepare legislation and environmental management guidelines related to domestic geological storage of carbon dioxide to enhance social acceptability, in addition to securing the safety of the long-term disposal of carbon dioxide and the environment.