Core Viewpoint - The completion of the left tunnel of the Taibai Mountain Tunnel on May 19 marks a significant milestone for the Shaanxi Meixian to Taibai Expressway project, which is expected to be completed and opened to traffic by 2025 [1][2] Group 1: Project Details - The Meixian to Taibai Expressway, a key national highway network link, spans approximately 75 kilometers, starting from the Lianhuo Expressway Fufeng Hub and connecting to the Fengta Expressway in Taibai County [2] - The left tunnel measures 5,259 meters, while the right tunnel is 5,277 meters long, making it the last tunnel of the entire expressway [1] - The construction faced significant geological challenges, including crossing eight geological fault zones and managing an average daily water inflow of 25,400 cubic meters, equivalent to filling ten standard swimming pools each day [1] Group 2: Construction Techniques and Environmental Measures - The construction team employed a combination of "grouting consolidation + advanced support" techniques to address the geological challenges, utilizing real-time monitoring tools to ensure safe excavation [1] - Advanced equipment such as hydraulic rock drilling rigs and wet spraying robots were introduced to significantly enhance excavation efficiency [1] - To balance construction and ecological protection, sedimentation pools and a wastewater treatment station were established at the tunnel entrance, utilizing new eco-friendly additives to treat wastewater effectively [1] Group 3: Economic and Social Impact - Once completed, the expressway will reduce travel time from Xi'an to Taibai to 1.5 hours, greatly facilitating the transportation of agricultural products along the route [2] - The project is expected to promote Taibai's ice and snow tourism and upgrade the Meixian kiwi industry, contributing to rural revitalization in southern Shaanxi and enhancing the connectivity between the Guanzhong Plain urban agglomeration and the Chengdu-Chongqing economic zone [2]