Uttarkashi, Nov 25 : As the auger machine encounters obstacles in the rubble, rescuers are considering alternative options such as manual drilling or creating a vertical escape passage for the 41 labourers trapped inside the Silkyara tunnel for the past 13 days, officials reported on Saturday.
Drilling at the collapsed portion of the tunnel faced another setback on Friday night after the auger machine encountered a hurdle, possibly a metal object. Before the setback, 46.8 meters of the 800 mm wide steel pipe had been pushed into the drilled passage out of the estimated 60-meter-long collapsed stretch. The six-inch wide tube for supplying essentials to the workers had traveled 57 meters.
With obstacles hindering horizontal drilling, the option of manual drilling is being considered for the remaining stretch of 10 to 12 meters. However, officials note that manual drilling is a more time-consuming process. Additionally, efforts are underway to create a vertical escape passage, with a large drilling machine positioned above the tunnel for vertical drilling.
The Border Roads Organisation (BRO) has already built a 1.5-km access road to the top of the tunnel, anticipating the need for vertical drilling. Although vertical drilling is a more time-consuming and complex option, it demands precision and caution due to the narrower space available on the top of the tunnel roof, as mentioned by international tunnelling expert Arnold Dicks.
Frustration is growing among the relatives of the trapped labourers as mechanical drilling faces repeated hurdles, causing delays in the rescue process. The multi-agency rescue effort began on November 12 when a portion of the under-construction tunnel on Uttarakhand’s Char Dham route collapsed due to a landslide, trapping workers inside. The trapped workers are receiving essential supplies through a six-inch wide pipe, and communication has been established using this pipe. An endoscopic camera has also been used to assess the conditions inside the tunnel.
