Studies
Studies of environmental impact by simulations
Mathematical simulation of atmospheric dispersion
The dispersion simulation by mathematical dispersion modeling enables the estimation of the environmental impact of pollutant emissions. The application of the atmospheric dispersion model allows the mathematical simulation of the concentration in air of the pollutants emitted from a source on the surrounding territory, for each hour of the considered time domain. The concentration values that are simulated at each receptor are elaborated in order to calculate the synthetic parameters (e.g. yearly or daily averages, concentration perecentiles), which can be compared to air quality limits. The model results are represented graphically by a map, on which the isopleths relevant to the chosen parameter are traced. For example, the isopleths relevant to the yearly averaged concentration can be traced, i.e. the lines along which the yearly averaged concentration calculated from the hourly data is uniform.
Dispersion models
Dispersion models are mathematical tools that allow the simplified description of the very complex phenomena relevant to the atmospheric dispersion of pollutants, by means of specific equations and algorithms. Several families of dispersion models are available, and each of these families of models comprises a large number of different software types, which apply the same general methods. Progress S.r.l. has gained a deep experience in the application of the CALPUFF model, realized by Earth Tech Inc. for the California Air Resources Board (CARB) and the U.S. Environmental Protection Agency (US EPA). CALPUFF is an advanced atmospheric dispersion model, belonging to the "puff" model family. It is suitable for the estimation of the dispersion of emissions from single or multiple industrial sources. It allows to calculate dry and wet deposition, building downwash, dispersion from point, area and volume sources, the gradual plume raising in function of the distance from the source, the influence of the soil orography on dispersion, and the dispersion in case of weak or absent wind. The dispersion coefficients are calculated from the turbulence parameters (u*, w*, LMO), instead of being calculated from the Pasquill-Gifford-Turner stability classes. This means that turbulence is described by continuous functions, instead of discrete ones. CALPUFF is one of the preferred models officially adopted by U.S. EPA for air quality estimation (Part 51 - Guideline on Air Quality Models. Federal Register, Vol. 68, No. 72, Tuesday, April 15, 2003 / Rules and Regulations). CALPUFF belongs to the class of models recommended for regulatory use.
Applications
Using specific methods, parameters and procedures, Progress S.r.l. applies simulation models in order to simulate the atmospheric dispersion of:
- specific gaseous chemical pollutants (nitrogen oxides, carbon monoxide, VOC, etc.);
- solid particulate matter (PTS, PM10);
- odour.
As far as concerns odour dispersion, Progress S.r.l. has gained an unique experience and competence at least in Italy. Among the studies that Progress S.r.l. conducts using dispersion models, there are:
- Anticipatory environmental impact studies relevant to atmospheric emissions, for the preventive environmental compatibility verification (e.g. environmental license applications
- procedures for environmental impact evaluation). The studies may regard new plants or plants subject to substantial modifications (extension works, displacement to a different site, etc.). In these cases the characteristics of the emissions may be defined from experimental data relevant to similar emissions, from data extracted from the database of Progress S.r.l., from literature data, etc.
- Environmental impact studies relevant to atmospheric emissions determined by monitorings for the verification of the compliance to the limits fixed by the law or by the competent authority (e.g. prescriptions in environmental licenses) or for the verification of environmental tolerability (specifically for odours)..
Click here to download the synthetic informative document about the environmental impact studies by simulation.
Land reclamations
Progress S.r.l. is active in the design and draft of characterization plans and studies for the reclamation of polluted soils, according to the D.M. 25th October 1999, no. 471. Progress S.r.l. provides for the execution of the analyses and the controls provided by the above mentioned ministerial decree, by making use of competent laboratories and research centres.