As the rescuers raced against time to evacuate the 41 workers trapped in an under-construction tunnel in Uttarakhand’s Uttarkashi, an international team of tunnelling experts arrived at the site on Monday. As the rescue operation entered the ninth day, International Tunnelling and Underground Space Association president Arnold Dix was among the experts at the site to oversee the operation.
The Oil and Natural Gas Corporation (ONGC) has undertaken the task of vertical drilling at the Barkot end of the Silkyara tunnel on the Char Dham route, part of which collapsed on November 12, sources said. The ONGC drilling head is set to visit the site on Monday and a report is expected to be submitted the very next day.
The Border Roads Organisation (BRO) will then finalise the alignment of the road based on the ONGC report by November 22 (Wednesday).
Vertical drilling at the Silkyara end has been assigned to the Rail Vikas Nigam Limited (RVNL). The BRO completed 970 metres of the access road leading to the tunnel out of the total planned 1,150 metres on Sunday. The remaining distance is expected to be covered by Monday.
The RVNL has placed a request for an electric connection, which the district administration is evaluating. The vertical drilling is scheduled to be completed by November 26 (Sunday), according to sources.
They added the RVNL has also planned for a 170-metre tunnel to be constructed using specific equipment, which will reach the site by November 21 (Tuesday). The setup is expected to be completed by November 23 (Thursday).Water resources have been identified with recycling options and the district magistrate’s permission is required to use the state government pipe.
Sources said that THDC India Ltd has been entrusted with a 483-metre tunnel construction after they completed a site assessment and manpower mobilisation. The tunnel boring will commence from Monday.
The National Highways and Infrastructure Development Corporation Ltd. (NHIDCL) has the responsibility of strengthening the tunnel and construction of an escape route, sources said. A 150 mm steel pipe is being set up through the debris for emergency services, and a third attempt for the same is underway.
The National Hydroelectric Power Corporation (NHPC) and the Satluj Jal Vidyut Nigam Limited (SJVNL) have been tasked with drilling a 1-1.2 metre-diameter borehole at the Silkyara end. The work is set to begin on Monday.
The Indian Army are on-site to monitor the progress. A drone has arrived at the tunnel site, which will help with aerial monitoring and facilitate the efficient completion of the project operation.
IAS officer Neeraj Khairwal, who has been appointed as the nodal officer by the Uttarakhand government to coordinate with various central agencies, is expected to reach the Silkyara tunnel today.