Tender For corrigendum : geologicalexploration by extension of 02 nos. existing drift of size 1.8x2.1m , rdr-2 by 100m length at el293m and rdr-3 by 150m length at el 418m at right bank with 04 nos. head room or working space (02 nos. on each drift) of size (5mx4mx4.5m) fo