Recyclable waste as a resource of construction material: policy and practice in the Netherlands (Reprinted from Trans. Instn Min. Metall., vol 108, 1999)

At present, about 15 000 000 t of recycled material is used annually in con struction in the Netherlands, yet about 40 000 000 t of the waste produced in the country is more or less suitable as construction material. The Minis try of Transport and Public Works is pursuing various measures to increase recycling, so that by 2010 20% of the demand for construction materials, or about 25 000 000 t/year, is expected to be met from waste. Obstacles to in creased recycling include the presence of contaminants, which either impair product quality or incur treatment costs, and possible health hazards, e.g . from asbestos, radiation and leachates. The recycled tonnage is mainly re use of concrete and brick debris; the Netherlands produces large quantities of dredging sludge, but separation of this into clean sand and a polluted silt fraction for disposal is currently economic only where the sand consti tutes more than 50%.