On the 13th, the Seoul Metropolitan Government announced that it would conduct ground-penetrating radar (GPR) surveys at large-scale underground excavation construction sites and their surroundings.
A GPR survey uses electromagnetic waves to measure underground structures and facilities. The city noted that this is a measure in response to recent ground subsidence incidents.
The city plans to first inspect the large-scale underground excavation construction sites and their surrounding areas, and then proceed with GPR surveys in locations selected by municipal districts and sections deemed necessary by the city.
First, the city will conduct GPR surveys in three sections of urban railway construction spanning 18.5 km and surrounding roads. The city has been conducting GPR surveys in these sections since the end of last month, deploying 41 personnel and 15 pieces of equipment.
The three areas around the urban railway construction sites that the city is concentrating on are the construction of Seoul Urban Railway Line 9, Phase 4 (Sections 1 to 3) at 4.1 km, the Dongbuk Line urban railway private investment project (Sections 1 to 4) at 13.4 km, and the Yeongdong-daero underground space complex development project at 1.0 km.
The city will also conduct concentrated inspections to strengthen safety management in sections of metropolitan railway construction where excavation is taking place in Seoul. This includes the Shin-Ansan Line at 12.1 km (from Seoksu Station to Yeouido Station) and the Metropolitan Area Express Railway (GTX-A) at 18.7 km (from Suseo Station to Seoul Station). The GPR survey in the Seoul section of the Shin-Ansan Line has been ongoing since early April.
The city plans to complete the survey and analysis of GPR surveys for 50 prioritized inspection areas along a 45 km section selected last year by eight municipal districts by the end of April. Previously, at the request of the Ministry of Land, Infrastructure and Transport, the city allowed municipal districts to autonomously submit areas requiring special inspections for ground subsidence, resulting in eight districts selecting and submitting 50 locations.
The city intends to conduct a demand survey again for 17 municipal districts that did not submit last year and carry out additional surveys. It will also conduct GPR surveys on sections that require inspections in priority maintenance zones created to enhance the efficiency of GPR surveys.
Han Byeong-yong, director of the Seoul Disaster and Safety Office, said, “We will do our best to strengthen GPR surveys and prepare measures to prevent similar incidents from occurring.”