Definite design for design and build of the first rock tunnel for motorways in Thailand. The tunnel runs through Phunamron mountain in Kanchanaburi province. It is a 2 km long twin tunnel with two traffic lanes in each direction. 

The work included risk analysis and prevention methods, supporting function design (fire and ventilation), roadway design (pavement, sidewalk, drainage and egress), portal design, tunnel water proofing system, rock initial support (reinforcement, shotcrete, etc.), permanent lining, instrumentation, specifications, BOQ, cost estimate and tender documents.