The Pohang Geothermal Project in South Korea was initiated in 2010 as a pilot program to harness the earth’s heat for power generation, exploring renewable energy sources deep beneath the Korean peninsula. The project became the focus of intense controversy following the magnitude 5.4 earthquake that struck Pohang on November 15, 2017. This unprecedented seismic event and its subsequent aftershocks raised immediate questions about the experimental facility’s role in the disaster, which was later confirmed.
Understanding the Pohang Geothermal Project and Induced Seismicity
The Pohang facility was an experimental Enhanced Geothermal System (EGS), a technology designed to generate electricity from hot, dry rock. The EGS process involved drilling two deep wells, PX-1 and PX-2, down to approximately four kilometers below the surface. High-pressure fluids were then injected into the deep rock to hydraulically fracture the formation, creating an artificial reservoir for heat exchange.
This fluid injection process carries the risk of induced seismicity, which describes earthquakes triggered by human industrial activity. Between January 2016 and September 2017, the project conducted five high-pressure hydraulic stimulations, injecting thousands of cubic meters of water. Scientific investigations confirmed that these operations increased pore pressure deep underground, activating a previously unmapped fault system.
The magnitude 5.4 earthquake, the second strongest in the country’s modern history, occurred only two months after the final stimulation. A government-appointed commission and multiple independent scientific studies definitively concluded that the geothermal project’s fluid injection was the direct cause of the quake. The seismic event was a runaway earthquake triggered by human intervention, and its magnitude was substantially larger than anticipated during the planning phases.
Immediate Consequences for Residents and Structures
The resulting earthquake was the most destructive seismic event ever recorded in South Korea, causing widespread damage to the densely populated city of Pohang. Initial assessments documented damage to over 2,165 private properties, with dozens suffering severe structural collapse. Total damaged structures were estimated at approximately 57,000, encompassing residential, commercial, and industrial buildings.
The seismic activity also impacted public infrastructure, with damage reported at 227 schools, 79 public offices, and 11 bridges. Total property damage was estimated to be between 85 billion and 300 billion won (US\(75 million to US\)290 million). The damage was amplified because local subsoil conditions intensified the seismic waves, leading to a measured peak ground acceleration of 0.58g.
Beyond the physical destruction, the earthquake had a significant human toll on Pohang residents. Over 80 people sustained injuries, and nearly 1,800 residents were forced to evacuate their homes to emergency shelters. The unexpected nature of the human-caused disaster created substantial psychological stress within the community. Studies indicated a two-fold increase in the risk of anxiety and stress-related disorders among residents in the most affected northern area.
Official Investigations and the Project’s Termination
Following the devastating earthquake, the South Korean government immediately suspended the project’s operations and launched a comprehensive investigation. The independent commission confirmed the link between the high-pressure fluid injection and the seismic event. This led to the project’s official and permanent termination in April 2019, ending the country’s first EGS pilot program due to the unacceptable risk to public safety.
The revelation that the disaster was induced by a state-backed project led to a massive legal and financial fallout. The government established a special act to provide a framework for fact-finding and a damage remedy process for the victims. This resulted in a large-scale class-action lawsuit filed by thousands of Pohang residents seeking compensation for property damage and psychological distress.
A district court initially ruled in favor of the plaintiffs, acknowledging the government’s responsibility and ordering compensation for mental anguish. This ruling prompted nearly 96% of Pohang’s population to join the lawsuit. However, an appellate court later overturned this decision, arguing that administrative failures did not meet the legal standard for negligence under state compensation law, despite the project causing the quake. The ongoing legal battle is now expected to proceed to the Supreme Court for a final determination on reparations.