This study attempted to calculate quantitatively the environmental load caused by the public works, and tried to estimate the costs of environmental hazards by utilizing an environmental value assessment technique(used in economics), with the objectiv...
This study attempted to calculate quantitatively the environmental load caused by the public works, and tried to estimate the costs of environmental hazards by utilizing an environmental value assessment technique(used in economics), with the objective of supplying useful information to assist in decision making for pro-environmental and economical construction projects.
Further this study worked out models assessing environmental and economic aspects of construction projects, and sought to establish a system which will enable us to determine whether a construction project is sustainable, through development of a methodology integrating each aspect of the assessment models. Towards that end, case analyses are conducted with the suggested assessment model for environmental economics, aiming at verifying the applicability of the model into actual construction projects.
As the result of study which has been carried out with the mentioned objective and methodology, I could draw conclusions which are summarized as follows.
Firstly, I performed research design to estimate the costs of environmental impacts by utilizing the Contingent Valuation Method(CVM) that is based on multi-attribute utility theory. As the result I could calculate the environmental cost per unit of basic pollution source in each criterion of environmental effects caused by construction project.
Secondly, I calculated the environmental loads which are generated over the whole life cycle of public construction works by utilizing LCA technique(a method of assessing environmental load), and proposed assessment model for environmental economics of construction projects by converting environmental hazards into monetary value. The proposed assessment model will help find alternative solution or improvement at planning or design stage for reducing environmental impacts and saving costs. I believe the model can be applied adequately in other industries as well as in construction field as a useful means to assist in environmental and economical decision making.
Lastly, I conducted case analyses of construction field to verify applicability of the proposed assessment model in the environmental economics. In this study I applied the proposed assessment model to such works as road, bridge, tunnel, railroad and environmental facilities. As a result of the analyses it was found that civil works such as road, bridge, tunnel and railroad generate maximum environmental impacts and require maximum costs during construction(at this stage they feature similar mode of inputting construction materials and equipment). As for environmental facilities, it was found that maximum environmental impacts and cost spending occur during operation(at this stage energy is consumed continuously to improve environment). Through these analytic results I conclude that construction projects will be more environment-friendly and economical with efficient input of materials and energy consumption during construction stage (for civil works) or during operation stage (for environmental facilities).
Through the case analyses I could confirm that the assessment model for environmental economics, proposed by me, are useful method supporting the planning and management of sustainable construction works not only in environmental aspect but also in economical aspect. The applicability of the assessment model have been thus verified, in my opinion.
Reduction of environmental impacts and economical saving will be achieved by identifying and improving environmental hazards at the stages where environmental and economic effects are largest(as discovered in this study). In particular, to optimize quantity of required material at planning and design stage based on diverse analysis and interpretation results, or to minimize energy consumption by efficient combination of input equipment, will enable reduction of environmental load and saving of environmental costs.