Sokhee Philemon Jung

This study examined trichloroethylene (TCE) and tetrachloroethylene (PCE) groundwater contamination at the Hanam and Bonchon Industrial Complexes in Gwangju, South Korea. It distinguished site-specific evidence confirmed by official investigations from scientifically plausible but unverified hypotheses and evaluated remediation strategies and institutional management approaches based on a conceptual site model (CSM). Official investigation reports and follow-up water-quality data released by local governments and public agencies, relevant legislation, peer-reviewed literature, and technical guidance available through August 25, 2026 were reviewed. At the Hanam Industrial Complex, 657 depth-discrete groundwater samples were collected from 171 locations during 2020–2023. The industrial-use groundwater quality standards were exceeded in 117 samples for TCE and 67 samples for PCE, with maximum concentrations of 27.982 mg/L and 5.691 mg/L, respectively. At the Bonchon Industrial Complex, TCE exceeded the applicable standard at 14 of 43 locations investigated during 2019–2021, with a maximum concentration of 0.678 mg/L, whereas PCE remained below the standard. These findings indicate that substantial baseline data on hydrogeologic conditions and depth-resolved contamination characteristics have been accumulated at both sites. Accordingly, the existing CSMs should be continuously refined by integrating previous investigation results with recent monitoring data, and candidate remediation technologies should be evaluated in a staged manner according to exposure-control, source-control, and plume-management objectives. Pump-and-treat, permeable reactive barriers, and in situ chemical oxidation were proposed as candidate technologies for site-specific evaluation at Hanam. At Bonchon, the existing strategy combining pump-and-treat and chemical oxidation may be supplemented by enhanced reductive dechlorination as a conditional option based on the detection of dechlorination by-products. Institutionally, the current Korean legal framework already provides mechanisms for groundwater-use restrictions, cleanup orders, direct public remediation, remediation financing, liability, and cost recovery. The principal institutional limitation therefore lies not in the absence of remediation authority itself, but in the insufficient integration of a national risk-based system for prioritizing high-risk complex contaminated sites, early public intervention for investigation, risk reduction, and remediation before final liability determination when necessary, and stable multi-year financing linked to subsequent cost recovery. This study therefore proposes a Korean Superfund not as a simple replication of the U.S. Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), but as a functional institutional model that integrates risk-based national prioritization through a Korean National Priorities List (K-NPL), early public intervention prior to final liability determination, stable long-term financing with cost recovery, CSM-based long-term management, and information disclosure within the existing Korean legal framework.

Stacked microbial fuel cells (MFC) have become a viable solution to circumvent the low voltage and power constraints of single-cell systems and allow the simultaneous treatment of wastewater and generation of bioelectricity. Nonetheless, the massive implementation is limited by stack instability, reversed voltage, distribution of internal resistance, and poor energy-gathering efficiency. This review offers a combined engineering insight into stacked MFC systems, with a focus on stack configurations (series, parallel, and hybrid), advanced electrode and membrane materials, voltage reversal phenomenon, and the critical role of the power management system and maximum power point tracking in stabilizing and enhancing the energy output. Moreover, the techno-economic evaluation and life-cycle analysis are also reviewed with a critical look at the scalability, sustainability of the environment, and cost-effectiveness of the system under the actual wastewater conditions. This review provides strategic insights into developing stacked MFC beyond the laboratory level models of the architectural realm to the actual wastewater treatment apparatus by integrating power electronics, economical structures, and architectural design.

Rare earth elements (REEs) are essential resources for high-tech industries including semiconductors, batteries, electric vehicles, and wind power generation; however, the current global supply chain is overwhelmingly concentrated in specific countries. As environmental pollution from mining and refining processes and geopolitical risks continue to intensify, the importance of recycling technologies that utilize electronic waste (e-waste) as an ‘urban mine’ is rapidly increasing. Against this background, this study aims to comprehensively compare pyrometallurgical, hydrometallurgical, and next-generation eco-friendly recovery technologies, while presenting technical and economic challenges and future development strategies. Electronic waste contains high concentrations of REEs, offering greater recovery potential than natural ores. Analysis revealed that existing pyrometallurgical and hydrometallurgical processes, despite their high recovery rates and efficiency, exhibit clear environmental limitations including massive energy consumption and wastewater generation. Next-generation technologies — including bioleaching, ionic liquids, and deep eutectic solvents (DES) — were found to have the potential to substantially reduce the environmental burden by eliminating hazardous chemicals and enhancing selective recovery performance. Iodide-iodine and thiourea-based leaching systems are also attracting attention as subjects for future research. In particular, life cycle assessment (LCA) results indicated that bioleaching showed lower values in certain environmental impact categories compared to conventional chemical leaching; however, these results may vary depending on feedstock characteristics, functional units, and system boundaries, and caution is advised against generalization. The EU has set a target of 25% domestic recycling of critical raw materials by 2030 through the Critical Raw Materials Act (CRMA), and the U.S. Department of Energy (DOE) is expanding support for e-waste-based REE recovery and refining demonstrations. Korea likewise needs to consider developing e-waste-based REE recovery technologies and establishing demand-linked supply chains, building on existing rare metal development strategies. In summary, bioleaching and low-hazard solvent-based technologies are assessed as promising alternatives for next-generation eco-friendly REE recovery, and further efforts toward demonstration-scale expansion, downstream refining advancement, and techno-economic validation are needed. Based on the collected data, this study examines technical and policy challenges and aims to provide foundational data for future policy improvements and research directions.

Electrochemistry underpins energy storage, energy conversion, and environmental processes; therefore, precise electrode terminology is essential for both science education and industrial communication. In Korea, however, long-standing translation practices for anode and cathode have produced recurring conceptual confusion in classrooms, journals, and technical documents. The root cause is that two distinct categories of terms, function-based terms and potential-based terms, have not been consistently separated in Korean translation. Historically, Michael Faraday introduced anode and cathode as theory-neutral terms denoting the surfaces through which electric current, according to the convention of his time, enters and leaves the decomposing body. They were not introduced as fixed polarity labels. Modern IUPAC definitions follow this functional logic: anode is the electrode at which oxidation occurs, and cathode is the electrode at which reduction occurs, independently of electrode polarity. Consequently, during discharge in a galvanic cell, the anode is the negative electrode, whereas in an electrolytic cell the electrode connected to the positive terminal of the external power supply is the anode. In rechargeable batteries, the same physical electrode alternates between anodic and cathodic roles during charge and discharge, which makes function-based names inherently variable for a fixed material. To address this variability, battery standards and industrial documents widely use positive electrode and negative electrode as potential-based terms for fixed electrode materials and cell components. IEC 60050-482 likewise specifies that the anode is the negative electrode during discharge and the positive electrode during charge, while the cathode shows the opposite correspondence. A comparison of Korea, China, and Japan reveals three distinct patterns. China institutionalizes the distinction between 阳极/阴极 as function-based terms and 正极/负极 as potential-based terms in national battery standards such as GB/T 2900.41-2008. Japanese standards, including JIS K 0213:2014, explicitly describe context-dependent correspondences, while the Japanese electrochemistry community has long discussed the need for clear separation. Korea already has function-based definitions in the Korean Chemical Society terminology glossary and battery terminology standards in KS C IEC 60050-482, yet a consistent operational principle separating function-based terms from potential-based terms has not been firmly established across education, academia, and industry. On this basis, this paper proposes three principles: 1) anode and cathode should be used as function-based terms and translated as 애노드/산화전극 and 캐소드/환원전극, respectively. 2) positive electrode and negative electrode should be used as potential-based terms and translated as 양극(또는 정극) and 음극(또는 부극), respectively. 3) the symbols (+) and (−) should be used as polarity markers for electrodes or terminals, not as fixed equivalents of anode and cathode. Adopting these principles can improve conceptual clarity in electrochemistry education, increase precision in industrial communication, and reduce translation errors in international scientific exchange.

In modern climate, energy, and environmental fields, optimizing energy efficiency and utilizing renewable energy resources have become central challenges. However, the current Korean scientific and technological terminology system indiscriminately applies the suffix ‘ryeok (力)’ to energy (E) and power (P) — concepts with strictly distinct physical dimensions — thereby undermining dimensional transparency at the morpheme level and causing cognitive confusion in educational and practical settings. This review analyzes, from a comparative perspective, the technological terminology systems of Korea, China, and Japan, which belong to the major Sino-character cultural sphere of Northeast Asia, in order to diagnose the structural limitations of the ryeok (力)-based nomenclature system. It further proposes a complementary terminology system centered on neung (能, energy) for energy- and energy-source-related terms and on ilryul (率, rate) for energy-transfer-rate-related terms. Furthermore, to clarify the physical origin of energy, this review examines “haek-eneoji” (nuclear energy) and “haekneung” as complementary terms for “wonjaryeok” (nuclear power), and introduces “jeongi-ilryul” and its abbreviated form “jeonilryul” as complementary terms for “jeonryeok” (electric power), thereby enhancing conceptual consistency between the mechanical and electrical domains. Rather than advocating for the immediate abolition of established standards, this review explores the possibility of using dimensionally transparent alternative names in parallel, aiming to secure educational clarity suitable for the era of energy transition and enhance the efficiency of scientific communication.

The Act on the Promotion of Biogas Production and Utilization, enacted in 2022 and enforced since 2023, represents South Korea’s first legal initiative to institutionalize the energy recovery of organic waste. It aims to support national efforts toward carbon neutrality and the transition to a circular economy. However, the Act is structurally biased toward a limited technological scope—primarily anaerobic digestion and methane production—thereby excluding promising emerging technologies such as biohydrogen generation, thermochemical gasification, and bioelectrochemical systems. This study critically analyzes the legal structure and implementation practices of the Act, identifying technical, economic, and social constraints that undermine its effectiveness. Key challenges include the increasing volume of organic waste, low energy recovery rates, the dominance of large-scale centralized infrastructure, and a lack of operational expertise. A comparative policy analysis of the United States, European Union, and Japan reveals the necessity of expanding the definition of bioenergy and designing technology-neutral regulatory frameworks. This review argues that the Biogas Act must move beyond its current methane- and anaerobic digestion-centric structure. For meaningful advancement in organic waste valorization and renewable energy development, the Act should be redesigned to incorporate high-value bioenergy technologies such as microbial fuel cells (MFC), microbial electrolysis cells (MEC), thermochemical gasification, and syngas-derived fuel production.

This study analyzes green remodeling and reconstruction in terms of carbon emissions, economic feasibility, and energy savings. It also evaluates the carbon reduction potential of sustainable building materials. Furthermore, global policy trends are comprehensively reviewed through literature-based quantitative analysis and comparative case studies. Key findings are as follows: 1) Green remodeling achieves up to a 46% reduction in carbon emissions compared to reconstruction, with 20–50% higher cost effectiveness, 2) Low-carbon concrete reduces production-phase carbon emissions by up to 40%, 3) Timber structures can sequester approximately 1.8 tons of carbon per ton of material over the long term, 4) The use of sustainable building materials is pivotal for overall carbon mitigation in buildings, 5) Several European countries employ certification schemes, financial incentives, and mandatory regulations to promote green construction, 6) With sufficient measures to alleviate initial investment costs, align stakeholder interests, and provide tax and financial support, the green remodeling market in South Korea has strong growth potential. Based on this analysis, the study offers four strategic recommendations to inform sustainable development strategies in the building sector and support the design of a national, long-term carbon-neutral roadmap: 1) Systematic expansion of green remodeling initiatives, 2) Provision of fiscal incentives and strengthened financial support, 3) Development and large-scale demonstration of sustainable new materials, 4) Promotion of green construction through integrated certification systems and regulatory frameworks. These strategies collectively contribute to maximizing carbon reduction across the construction industry.

Effluent quality standards and energy self-sufficiency in wastewater treatment have emerged as key challenges for sustainable water management and climate change response globally. Rapid industrialization and urbanization have increased wastewater discharge, leading to frequent detection of hazardous substances and pharmaceutical residues in influent waters. In response, many countries are enhancing water quality standards and adopting advanced technologies. The United States and Japan implement effluent standards and remote water quality monitoring systems that reflect regional and seasonal characteristics. Conversely, Korea classifies effluent standards into only four regions and applies uniform criteria without considering seasonal variations. Additionally, inadequate management of emerging contaminants and the relaxation of total organic carbon (TOC) standards have exacerbated algal bloom phenomena. Although treatment standards for total nitrogen (TN) and total phosphorus (TP) have been strengthened, corresponding technological advancements and infrastructure remain insufficient. Reflecting integrated eco-toxicity management systems from the United States and Germany, Korea urgently needs a system enabling quantitative assessment among Asian countries. Furthermore, implementation of energy self-sufficient wastewater treatment technologies to reduce greenhouse gas emissions and electricity consumption at treatment plants is essential, yet Korea faces issues such as insufficient infrastructure, inadequate institutional frameworks, and insufficient incentives. A comprehensive national climate and energy strategy, along with collaborative models involving local communities, is necessary. Advanced technologies, inspired by Germany’s combined heat and power (CHP) systems and Japan’s biogas utilization methods, should be introduced. Ultimately, active governmental policy and financial support are crucial for developing and commercializing microbial electrochemical systems (MES) that convert wastewater directly into energy. This study aims to provide policy and technological directions for improving Korea’s wastewater treatment system by comparing and analyzing domestic and international cases of effluent quality standards and energy self-sufficiency.

Per- and polyfluoroalkyl substances (PFAS) are widely used not only in consumer products but also in semiconductor manufacturing due to their exceptional resistance to heat, water, and oil, which stems from the strong covalent bonds between carbon and fluorine atoms. However, the long-chain structure of PFAS leads to high bioaccumulation potential and possible carcinogenicity, resulting in their regulation as persistent organic pollutants under the Stockholm Convention. Recently, the World Health Organization (WHO) reclassified perfluorooctanoic acid (PFOA) as a Group 1 carcinogen and perfluorooctane sulfonic acid (PFOS) as a Group 2B possible carcinogen, thereby tightening global regulatory standards. Although South Korea has implemented regulations on PFAS, its current standards remain relatively lenient compared to those of the United States, the European Union, and other major East Asian countries. For instance, the U.S. regulates PFOA and PFOS in drinking water at 4ng/L each, and the EU limits the combined total of 20 PFAS compounds to 100ng/L. In contrast, South Korea regulates PFOA and PFOS individually or combined at 70ng/L, and PFHxS at 480ng/L. Based on the toxicity of PFAS and the insufficiency of current domestic regulations, this study argues for stricter national standards and proposes the following policy directions: (1) strengthen drinking water standards to protect public health, (2) establish routine monitoring systems for groundwater and surface water in major watershed areas, (3) introduce a certification system for PFAS-free products, and (4) enforce phased regulations on PFAS use in the semiconductor industry, along with increased government support for research and development (R&D) of alternative substances.