Accident Investigation Committee: "Guri Ground Subsidence Accident Due to Poor Management of Byeollae Line Construction" ... Contractor to Face Administrative Sanctions

Subsidence Accident Site in Guri City [Provided by Guri City]

[Asia Economy Reporter La Young-cheol] The cause of the large-scale ground subsidence accident that occurred last August in Guri, Gyeonggi Province was investigated to be due to poor management of the nearby Byeollae Line double-track subway tunnel construction.

The Ministry of Land, Infrastructure and Transport's Guri City Accident Investigation Committee stated on the 29th, "The tunnel construction contractor could have anticipated the vulnerability of the ground around the accident site, but due to inadequate management such as not taking appropriate reinforcement measures, the ground subsidence occurred."

In particular, about 10 days before the accident, when excavating 12 meters behind the accident site, excessive leakage water flowed into the tunnel as a precursor phenomenon, but it was confirmed that the contractor excavated according to the existing design without additional ground investigation or reinforcement.

However, the investigation committee added, "As a result of CCTV (closed-circuit television) inspections of two sewage pipes and two stormwater pipes within the accident site, no significant defects were found, and it was determined that there was no impact due to aging of the sewage and stormwater pipes."

The committee proposed that, to prevent recurrence of the accident, the current drilling investigations conducted every 100 to 200 meters during the tunnel construction design phase should be conducted at least once every 50 meters.

They also included strengthening ground investigations to select routes and construction methods, and utilizing various ground information such as the integrated underground information system.

Additionally, they suggested the permanent deployment of specialized technicians for ground condition verification and reinforcement method decisions, consulting external experts during construction of vulnerable sections, and applying an automatic measurement system capable of real-time accident detection.

The committee announced, "We plan to take administrative actions early next year in consultation with the relevant authorities against the contractor and supervision company responsible for causing the ground subsidence accident."

Earlier, on August 26 around 3:30 PM, a large-scale ground subsidence accident with a diameter of 16 meters and a depth of 21 meters occurred on a road in Gyomun-dong, Guri, Gyeonggi Province, disrupting water supply and electricity to nearby apartments.

Immediately after the accident, Guri City activated the Guri City Disaster and Safety Countermeasures Headquarters with the mayor as the head, and formed the "Guri City Accident Investigation and Safety Measures Committee" consisting of seven experts in water supply and drainage and tunnels to investigate the cause.

The Ministry of Land, Infrastructure and Transport also formed the Guri City Ground Subsidence Central Underground Accident Investigation Committee with eight experts in various fields, extended the investigation period from the original two months to four months, held 11 plenary meetings to discuss and announce the cause of the accident.

Meanwhile, An Seung-nam, mayor of Guri City, stated through his social media on the same day, "The investigation into this accident has clearly shown that it was due to the contractor's poor construction," and added, "We will hold Hyundai Construction, the contractor, along with five other companies and the supervision company strictly accountable through administrative actions, and we will thoroughly ensure no gaps in recurrence prevention measures."

This content was produced with the assistance of AI translation services.