Land use, redevelopment, and transformation issues are complex. Decision-makers’ or actors’ response to urban development is driven by socioeconomic and political factors, transforming overall land use [1, 2]. Land use and regional economic growth are often mutually beneficial for urban development. Brownfield redevelopment is often regarded as a part of land sustainability policies because it can benefit the environment, economy, and society in urban areas . On the other hand, the land value of the brownfield is usually high if it is located in an area with relatively mature development conditions, such as environmental, economic, and social characteristics [4, 5]. The success factors of brownfields are often accompanied by zoning conditions for facilitating the redevelopment of land reuse . The motivation for brownfield redevelopment for local governments is regional development; accordingly, brownfield research has increasingly focused on the sustainability of the local environment, economy, and social conditions for determining the best approach [7–11].
Brownfield causes various environmental, social, and economic impacts before redevelopment. In the environmental dimension, the transmission and diffusion of pollutants may endanger human health and the environment and abolishes natural resources. Brownfield has reduced tax revenue, increased local unemployment rate, and hindered economic development, which reduces the value of the surrounding land. In the social dimension, brownfields are a concern for public security . Brownfield potentially attracts criminals and illegal activities, which are detrimental to urban development, neighbourhood relationships, and local living standards, further depleting public resources . Furthermore, the land use decision of brownfields during long-term redevelopment cannot usually respond to changes in dynamic environmental, economic, and social conditions. The brownfield redevelopment has not been linked to sustainable development then it has led to the decoupling of the redevelopment of brownfields from the national land management strategy [14, 15]. For the decision-making tool of brownfield sustainability, indicators have been developed to assess the effectiveness of this approach using drive-pressure-state-impact-response or quantitative analysis [16–20].
Land governance policy should make use of scientific urban research and benefits of sustainability, particularly in brownfield issues [21–23]. However, many researchers have argued that the abundance of electronic information cannot improve the communication gap between the government and stakeholders . In complex brownfield development, if the information is not transparent, most investors remain uncertain about the reuse vision of land policy planning. Besides, effective quantitative analysis for the scenario evaluation of brownfields requires large datasets even though data-driven analysis has improved public communication about the implementation of sustainable development goals in mega-cities [25, 26]. Therefore, further research is needed for reducing the uncertainty resulting from electronic information to land governance strategies. Some experts have explained that the diverse and complex socio-economic and environmental conditions can improve the solution of land governance according to three themes: (1) land change intention plans driven by visualization analysis, (2) territorial governance process of public participation and communication, and (3) external conditions for planning and implementation [2, 24]. If the decision system combines rich social, economic, and environmental information derived from government open data, stakeholders, such as landowners, developers, and regulatory agencies, can effectively evaluate the land value, environmental benefits, and social impacts, thus reducing investment uncertainty [27–31]. The government can employ the decision system as the main platform for public communication and review the benefits of promoting various brownfield plans .
Rapid changes in Taiwan have shortened the life cycle of each industry and have created a large area of contaminated land. In Taiwan, industrial density is approximately 2.66 km2 and this contaminated land of industry has resulted in approximately 120,000 abandoned factories . The number of contaminated sites in Taiwan continues to grow annually under the current land use scenario. In Taiwan, the five types of contaminated sites are factories, gas stations, agricultural land, storage tanks, and others, and the numbers under each of these land use types account for 4.66%, 2.11%, 91.18%, 0.14%, and 2.00%, respectively. Environmental remediation is the main strategy for managing contaminated sites for promoting the reuse of contaminated sites in Taiwan. Polluted agricultural land accounts for the majority of land use areas eligible for Soil and Groundwater Pollution Remediation Funds. Investigating potentially high-pollution agricultural land began in 2002. Approximately 73.22% of this land was cleared by 2020 and released from government control. The government expects all polluted agricultural land to be delisted by 2021, which means that most decontaminated sites will be agricultural land and not other polluted types. Presently, site management has focused on a remediation topic but has failed to deliver deeper insights into the comprehensive governance of urban planning.
According to information published by the Taiwan Environmental Protection Agency, 3.5 and 6.6 years are required on average for delisting controlled and remediation sites, respectively. According to Article 24 of the Soil and Groundwater Remediation Act, the objectives of the remediation plan could be flexible and depend on the results of the health risk assessment. However, for contaminated sites declared as remediation sites, the land-use types cannot be changed until relevant pollutants are removed to the extent that the contamination level is below the pollution control standards. Many highly contaminated sites in Taiwan are not ready for redevelopment because of the challenges in removing pollutants. Landowners and developers remain cautious about the uncertainties surrounding land investment ; therefore, 85% of the listed remediation sites have not been delisted. Presently, only a large investment in remediation funds can delist a site from the category of contaminated land.
The social, economic, and environmental impacts of brownfield redevelopment in the stages of remediation, redevelopment, and reuse are important information. This study contributes to improved decision-making regarding brownfield management. Large external information based on government open data must be considered for market analysis before decisions on brownfield investments are made by landowners. Regulators can incorporate environmental and social impacts to improve the supervision benefits for brownfield redevelopment. Considering these elements, this study has combined open data of the socioeconomic geographic information near contaminated land and has analysed the potential for sustainable development in Taiwan’s various regions. The four goals of our research were to (1) to identify the sustainable development dimensions and factors to be considered for brownfield redevelopment planning; (2) to construct a sustainability evaluation system and linked database for brownfield redevelopment in the social, economic, and environmental dimensions, based on the open data published by the government of Taiwan; (3) to establish an evaluation tool for brownfield redevelopment queries; and (4) to present a case study of Taiwan’s management strategies for brownfield redevelopment.