ESTIMATING THE URBAN MINING POTENTIAL OF JURONG LAKE DISTRICT (JLD)

Abstract

The general idea of this research is the attempt to extend the idea of "urban mining" to construction, regarding the city as a huge source of different types of re-usable building materials. Every year a certain amount of buildings is demolished and that is accompanied by producing many solid wastes. However, there is a high potential capacity for the reuse of these materials. The Building and Construction Authority (BCA) wants Construction and Demolition (C&D) waste to go ‘upcycle’ so that they are used back in buildings rather than low-value material like kerbs. The average amount of C&D waste available for reuse is estimated to be 2 million tons per year. (Building and Construction Authority, 2008). As a country with high urban activities, the demand for materials increases, and the rate of raw materials extraction will do the same. This contributes to environmental implications in the form of emissions and depletion of finite natural resources. Also, with our landfills reaching capacity, there is a need for urban mining to become an integral part of material recycling. The objective of this study is to quantify the concrete and steel contents contained in the existing Science Centre Singapore currently located in the Jurong Lake District (JLD). JLD is a 360ha mixed-use district in western Singapore and is intended to support the city’s economic growth for the next 10 to 15 years (Urban Redevelopment Authority, 2012). Within the next eight to thirteen years’ time, the existing Science Centre will be demolished and relocated to the area next to Chinese Garden MRT station also within JLD. This existing Science Centre will be seen as an ‘urban mine’ and for this research, the amount of materials which can be recovered from this building to the new building will be quantified. In addition to this, the environmental impacts of replacing primary materials with recycled materials will be compared, with reference to Carbon Dioxide (CO2) emissions. The results show that a volume of 81,532.71 m3 of concrete and 14,262.25 tonnes of steel is contained in the existing Science Centre. This amount of concrete can recover approximately 102,222 tonnes of Recycled Concrete Aggregates (RCA), and the amount of steel is almost 100% recoverable. The total amount of CO2 reduction achieved from the construction of new Science Centre after replacement of Natural III Aggregates (NA) with RCA amounts to 87,836.5 kg. Ultimately, the mining of recovered RCA from the existing Science Centre will result in a total of 533,596.91 kg of CO2 reduction. There is a potential for urban mining in JLD that should be considered. However, there are some issues that also must be considered and they will be discussed in this paper. The result of this research could provide an important reference for future strategy making in terms of urban mining in Singapore.