Urumqi's first metro line—Urumqi Metro Line 1—has recently started construction and is expected to be completed and open to traffic by 2019. How is this 27-kilometer line being built? How does building a metro here differ from building metros in other regions?
　　
　　Recently, Sina Finance visited the metro construction site managed by China Railway First Group. The project started on March 20 this year. After extensive preliminary preparations, the tunnel has just been excavated 19 meters, which is already the fastest speed. Due to climate reasons, the annual construction period here is less than 9 months, and tunnel excavation alone requires a long time. In addition, there are interchange stations, station parking lines, and other engineering projects. Completion by 2018 is already the fastest possible speed.
　　
　　In November 2012, the Xinjiang Urumqi Urban Rail Transit Project held a groundbreaking ceremony in front of the Santunbei Water Park, which is also the starting station of Line 1. The final construction plan was slightly adjusted. Line 1 has a total length of 27.615 kilometers, started construction on March 20 this year, and is planned to open to traffic by 2019. The feasibility study cost estimate for the project is 21.6 billion yuan, an increase from the estimated investment of 17.9 billion yuan.
　　
　　Line 1 starts from Santunbei Station on the east side of the South Suburb Passenger Transport Station in Urumqi in the south and extends north to Diwopu International Airport. It is divided into 19 bid sections, undertaken by 19 construction units and 10 supervision units. The terrain along the entire line is undulating, passing through various terrain areas and four fault zones, which have become the main geological problems encountered in the construction of Line 1. The activity characteristics of the fault zones and engineering treatment measures have been solved through special scientific research.
　　
　　According to the construction manager of the Third Company of China Railway First Group, since the main geological structure along the line is sand and gravel layers, 15 construction bid sections of the entire line are excavated manually, and only 3 bid sections use the familiar shield tunneling method.
　　　
　　Although the fault zone problem has been basically solved, many problems unexpected in the construction plan were still encountered during construction.
　　
　　The Third Company of China Railway First Group is responsible for the construction of Bid Section 11. He Qi, the chief engineer of this project, told Sina Finance that Bid Section 11 is "one station and one interval," namely the station construction of Railway Bureau Station and the construction of the interval between Railway Bureau Station and Sports Center Station. Among them, Railway Bureau Station is a planned interchange station for Line 1 and Line 4. Line 4 passes beneath Line 1, so the construction of both stations must be completed in this construction.
　　
　　He Qi said that because it is an interchange station construction, the construction requires an ultra-deep foundation pit with a depth of 28.2 meters, which is rare nationwide. In addition, Urumqi previously had no relevant data or construction experience to draw on. Furthermore, Railway Bureau Station has a total of 6 entrances and exits, 3 of which require underground excavation, i.e., excavation from below the surface, which is more difficult than open excavation. "The construction of all three entrances and exits must pass beneath urban pipelines, and the closest intersection with urban pipelines is only 2 meters, which places high demands on construction control," He Qi said.
　　
　　An engineer at the construction site stated that compared with metro construction in other cities, Urumqi Metro has significantly higher security requirements in the design and construction process, with the highest security requirements nationwide, which also makes the project relatively complex and increases construction difficulty.