Estimation of Gas and Dust Emissions in Construction Sites of a Motorway Project

Abstract

Minimizing the environmental impacts is a challenging task to achieve sustainability in road constructions. Although they are only temporary, the environmental burdens of building activities can have a great impact on the environment and communities, and must be properly assessed and mitigated. A comprehensive evaluation of the impacts requires the consideration of all construction activities, construction sites and the type and operation time of off-road machines and plants that will be used in each site. In this paper, a case study relating to the project of a motorway was carried out with the following objectives: (i) to estimate the dust and gases arising from the whole construction process and identify the most critical pollutants in terms of emitted quantity; (ii) to investigate the worksites, activities and processes with the greatest impact from an emissive standpoint, and (iii) to propose a rational approach for designing and putting in place effective mitigation measures. Carbon oxide (CO), nitrogen oxides (NOx), and fine particulate matter (PM10) emissions have been estimated by applying different models, methodologies and databases, depending on the construction process under analysis, and an emissive balance sheet has been produced. Results showed that CO is the pollutant released in the greatest quantity, followed by NOx. The emission of PM10, mainly due to the movement of trucks on unpaved roads, is one order of magnitude less with respect to CO and NOx, but produces the most perceived and undesired effects of the construction process in the interested communities. Tunnels and bridge are the components of a road with the greatest impact in terms of air emissions.

Bioremediation of Polycyclic Aromatic Hydrocarbons from Industry Contaminated Soil Using Indigenous Bacillus spp.

“…According to the literature, the most important hydrocarbon-degrading bacterial genera in soil environments include Bacillus spp. [10,11,25]. A typical substrate for Bacillus spp.…”

Assessment of the Impact of CO, NOx and PM10 on Air Quality during Road Construction and Operation Phases

“…The models used for the calculation of the PM 10 emission factors are reported in Table 4. Major details of the calculations are reported in [9]. For the calculation of the traffic-related emissions in operation, reference was made to the database provided by ISPRA-SINAnet [34] for the motorways.…”

“…During construction, the site activities such as material production and transportation, equipment and machineries, and excavation and earthmoving release into the atmosphere a large amount of pollutants [9,10]. Off-road machines, which are diesel-powered, are a significant font of direct air emissions such as carbon oxide (CO), nitrogen oxides (NO x ), and particular matter (PM).…”

“…They found that emission factors were higher on-road compared to laboratory conditions and highest particle emissions were observed on-road during accelerations and engine braking. Other studies studied the influence of construction sites on air quality and focused on the estimation of emissions from road construction [9,[19][20][21]. Mulenski et al [22] investigated on PM 2,5 and PM 10 emission factors to assess emission inventories for the main construction activities.…”

“…In this way, it is possible to provide accurately indications in the development of effective strategies for pollution control and air quality management at roadsides for the aim of making the pollutants concentration tolerable and complying with the regulations. Previous papers reporting the results on the on-going research focused on the detailed analysis of the amount of emissions deriving from construction of the motorway [9] and on the study of the dispersion of concentration of PM 10 emissions nearby the worksites [10]. The present paper takes into account also the traffic-related emissions during the operational phase for a comprehensive evaluation of the air emissions of a motorway and in order to quantify the real impact of the two road life steps on the air quality.…”