rescuers had bored 36 metres into the hill above the silkyara tunnel by monday evening in their effort to reach 41 workers trapped inside for 15 days as rat-hole mining experts also reached the disaster site to help tackle the challenge simultaneously from another front. twelve rat-hole mining experts will be involved in manual drilling and excavation horizontally through the last 10- or 12-metre stretch of debris of the collapsed portion of the under-construction tunnel on uttarakhand’s char dham route. th