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Environmental pollution is considered to be one of the main concerns in the construction industry. Environmental pollution has become a major challenge to construction projects due to the huge amount of pollution caused by construction projects. There are different types of environmental impact indicators, such as the greenhouse gas (GHG) footprint, eutrophication potential (EP), acidification potential (AP), human health (HH) particulate, ozone depletion, and smog. Each of these environmental impact indicators can be linked to different phases of the construction projects. The overall environmental impact indicators can be divided into direct, indirect, and operational emissions. This paper presents a Building Information Modeling (BIM)-based methodology for the assessment of environmental impacts in road construction projects. The model takes into account the overall life cycle of the road construction project, which is divided into: manufacturing phase, transportation phase, construction phase, maintenance phase, operational phase, recycling phase, and deconstruction phase. A case study is presented to demonstrate the applicability of the proposed model. The proposed model solves a major problem for road construction project teams who want to assess the environmental impact indicators associated with their project prior to the start of the execution of their projects.

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In this paper, the technical capabilities of a lab-scale electrodeionization (EDI) process and its basic technology electrodialysis (ED) process that used for removing NO 3 from nitrate-contaminated groundwater were investigated. The EDI unit with three chambers (anode, diluted and cathode) was used; it utilized electricity to regenerate ion-exchange resins instead of chemicals. At fi rst, the voltage-current (V-I) characteristic curves about the ED and EDI processes were studied, and then chose the optimum operating voltage which based on the curves. The effects of operational parameters (voltage, water fl ow rate and initial NO 3-N concentration) on nitrate removal rate and concentration effect of ED and different ion-exchange resins, the proportion of anion and cation resins and the voltage used for regeneration of EDI were investigated. The results of ED showed that NO 3-N concentration could be reduced from initial 50-300 mg/l to 1-6 mg/l, with the removal rate 99% and the conductivity could be reduced to less than 10 µs/ cm. Under the conditions of equal (1-8 l/h) and unequal (1:1,2,3,4,5,6,7,8 l/h) water fl ow rate between concentrated and diluted water, the concentrated water could be reached to 2-5 times more than the initial water. The current effi ciency and energy consumption was 17-34% and 0.-1.7 W•h/l, respectively. It was shown that ED was effective to NO 3 removal and concentration. As to EDI process, the results showed that continuous electrodeionization could regenerate the resins effectively from simulated nitrate-contaminated water. Under the condition of 50 V as the regenerate voltage, after 90 h, the regeneration rate was as high as 60%. In addition, the NO 3-N concentration of the diluted water was reduced to 5 mg/l from initial 50 mg/l. As a fundamental technology of in-situ remediation for groundwater contamination, the process was proved to be feasible and provided foundation for further research.

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