Twin-tube 700 m Valik tunnel on D5 highway to be driven in dolomitic limestone using NATM with drill/blast starting 2001. December 1999.  Notice of intention to construct Valik tunnel on D5 motorway for Czech Highways Directorate, Prague, fax +420 28400 9194. Visit www.czech.cz 36/01.Valik tunnel under construction by Metrostav using unique concept in which central buttress of reinforced concrete supported on micropiles is installed in pilot drive between parallel tubes in 330 m-long natural tunnel. Four-phase sequential excavation of main tunnels using NATM techniques with Atlas Copco Rocket Boomer L2 C drillrig. Visit www.metrostav.cz and www.boomer-rig.com 50/04.Contractor Metrostav constructing 380 m-long Valik twin-tube tunnel on Prague-Nuremberg motorway D5 in soft ground with reinforced concrete buttress installed in central pilot prior to excavation of top heading and bench in main drives using Atlas Copco Rocket Boomer L2 C and Swellex rockbolts. Visit www.atlascopco.com and www.metrostav.cz 19/05.