AMSTERDAM: Five months before the first Formula 1 race in the Netherlands since 1985, organisers have finally started the elaborate renovation of their picturesque, but outdated, circuit in the sandy dunes of Zandvoort. A range of environmentalist claims and court cases in recent months threatened to put the Dutch Grand Prix in danger, as organisers still had to obtain the necessary permits for the race. But race directors on Monday said they were certain that the event would go ahead on May 3 as planned. ”All is going according to plan”, circuit director Robert Overdijk told reporters. ”We have no concern whatsoever about making it on time.” Earlier this month, a court dismissed claims by nature activists who said the track builders were demolishing precious dune reserves, which are the home of endangered species such as the natterjack toad and sand lizard. This followed earlier victories against claims on air and noise pollution, and allowed work on the overhaul of the circuit, where Niki Lauda was the last winner of a Grand Prix almost 35 years ago, to start. More than 100 builders are now working frantically to get the Zandvoort circuit, hemmed in between the Dutch coast and a large nature reserve some 25 kilometres (15.5 miles) west of Amsterdam, ready for Grand Prix racing in 2020. The circuit, first built in 1948, had to be completely redesigned, adding banked curves with angles of up to 18 degrees to the lap and introducing a new top layer developed specifically for the conditions in Zandvoort.