Dream Hub is a massive $40 billion redevelopment project in the heart of Seoul, South Korea encompassing an international business district spanning over 34 million square feet and hosting what is to be the tallest building in Asia, thus, landing Seoul on the map of cities with the world’s tallest skyscrapers. This substantial urban development will span over 140 acres and will include an international business district, residential neighborhoods, world-class retail centers, cultural institutions, educational facilities, along with major transportation hubs intermixed with large urban parks adjacent to the Han River. The site for this redevelopment formerly served as the rail yard foundry and locomotive maintenance center for Korea Rail (KORAIL) for over 100 years, which through the years, has resulted in significant environmental impacts to both soil and groundwater throughout the site.
As part of the remedial effort, Directional Technologies, Inc., partnering with AMEC Environmental & Infrastructure and IS2B were retained by Samsung C&T, a subsidiary of Korea’s largest conglomerate, to serve as the lead horizontal remediation well technical consultant. DTI provided the horizontal engineering designs, well materials and worked with an in-country directional utility drilling contractor to install over 1,100 meters (3,300 feet) of horizontal piping, at an average depth of 4.5 meters (14.8 feet). Due to the aggressive time frame of the redevelopment project schedule, the field effort had to take place within a narrow window with subzero temperatures not recorded in Seoul in over 55 years. Although the local Korean utility contractor had no experience in installing slotted screen material or with environmental related projects, DTI provided the critical technical guidance and know-how to successfully install all six horizontal remediation wells within a one-week time period, on time and within budget.
Each horizontal well will be connected to dedicated 40 HP, high-vacuum, oil sealed liquid ring pumps as part of a multiphase extraction system to collect both free product and organic contaminants within the soil vadose zone in order to minimize the potential health risks to workers during the planned large-scale site excavation phase. The application of horizontal wells for an environmental remedial approach has never been successfully applied in the Republic of Korea. DTI’s horizontal wells at Yongsan are the first-of-its-kind application in Korea as part of a high vacuum, multiphase extraction system.