When The Fording River Coal Mine, in the extreme southeast corner of British Columbia, needed a Heavy Haul Road river crossing designed specifically to dismantle easily at the end of its service life, AIL's engineering team waded into the challenge.

The development of a procedure to dismantle the entire structure with minimal environmental impact on the Fording River, was critical. This ruled out the use of encased concrete reinforcement ribs, as considerably more debris would likely fall into the river as the structure was dismantled. AIL's Design Engineer devised a system of full-periphery steel ribs to give the structure the strength and tear-down properties that were needed. This was a key factor in securing this project. AIL's established practice of shape monitoring during construction and backfilling was a valuable asset throughout the project.

The structure has a span of 17 m, a rise of 8.563 m and a length of 42 m. The total loading weight for the structure was 542,514 kg. AIL's Vist-A-Wall MSE Structural Wall System (Welded Wire Wall with Cobble Stone) was used for the headwalls. A triple-stack series of AIL Welded Wire Gabion Baskets was used as a safety barrier for the large vehicles. Their 3 m stack height was perfect to reach the mining code's requirement of 66% the height of the largest unit's wheels.

In addition to protecting the eco-system of the Fording River, the Super•Cor and Vist-A-Wall components used at Fording River - already made from high-quality recycled steel - may also be recycled after dismantling, providing an extra opportunity for an environmental benefit.

Project partners included Kerr Wood Leidal Consulting Engineers and Golder Associates as the geotechnical engineers. AIL's Engineering and Technical Team members were on-site for several weeks during critical junctures. The project is scheduled to complete in November of 2009. Watch for completed project photos in a future issue of Profiles.