Special project in record pace

Boskalis Netherlands has been appointed by Attero as the main contractor on the Dak van Drenthe project. Their task is to deliver the comprehensive project in record time. We speak to manager Olaf Willemse.

Regionally, people still often talk about the VAM mountain, after the Vuil Afvoer Maatschappij that was founded in 1928. For decades it transported waste by train from The Hague to Wijster in Drenthe. Over the years, waste dumping became more and more about waste recycling and now energy generation. In short, a sector in which much has been invested in connection with environmental measures.

Highest point

The transition from a waste mountain to the recreational Roof of Drenthe has been awarded to Boskalis, where Olaf Willemse is manager. Olaf specializes in dry earthmoving falling under the business line Rivers and Dikes. "Boskalis was tasked with covering an 800-meter-long embankment and raising it by 15 meters, which would create the highest point in the province," he says. "On top of that, a 460-meter-long course with a 16.4% gradient was to be constructed. With the application of the asphalt, the job was accomplished. That job took place during the construction vacations in order to deliver the course at the beginning of September. This was followed by testing, before the final result could be released for the European Cycling Championships."

Regarding this project, Boskalis was awarded one of the two contracts. Olaf: "The contract for sealing the waste mountain itself was awarded to Boskalis through Attero. The second contract was for the installation of the bike trail on the mountain which was put out to the market by the province of Drenthe and awarded to Avitec from Nieuw-Buinen."

Green light

"We were given a tight time schedule from May 1 to September 1, 2023, then the total project had to be delivered before the said event. Immediately after the green light was given to Boskalis, we started packing the pile with bottom ash. On top of that, Trisoplast was applied by an Attero contractor. It provides environmentally friendly stabilization. On top of that, our subcontractor Cofra rolled out a High Density Poly Ethylene (HDPE) film. We then applied 30 centimeters of soil on top of that and on top of that, to finish, a finishing layer of 80 centimeters."

Boskalis' duties also included the construction of bike paths, sand and rubble road. Because of the short lead time, work began immediately after obtaining the preliminary permit. Olaf: "Even while making the planning in the tender phase, we saw that it was going to be pretty tight. There was little preparation time, which is why we started as soon as possible. We worked long days and the construction vacation was unfortunately not an option for our people on site. An uncertain factor in such a project remains the weather. For example, the laying of the foil stopped for two days because of a wind that was too strong."

High production

Olaf experienced the cooperation with Attero as particularly pleasant: "When you have such a short lead time, you have to act together. The fact that we handled everything in the right way is highly appreciated by Attero. The fact that we as Boskalis are used to delivering quality with high production is part of the reason we were awarded the work. Boskalis did all the coordination including that of the various subcontractors and Trisoplast working directly for Attero."