Environmental Assessment encompasses various phases of a complex investigation that results in knowing the actual environmental conditions of a site. This diagnostic will be the base for decisions to be made and actions to be taken for the remediation of eventual existing environmental impacts.
The work carried out by SGW Services to obtain an environmental diagnostic encompasses studies of the soil, groundwater and surface water based on Brazilian legislation and international standards, and is supported by a highly specialized multi-disciplinary team.
Confirmatory Environmental Investigation
In this phase, investigations are carried out based on the Preliminary Environmental Assessment (Phase I) with the objective of confirming the existence of an environmental impact. These investigations encompass:
- Local hydro-geological assessment.
- Survey of sources of contamination and receivers.
- Boring and installation of monitoring wells.
- Characterization of the preferential direction of flow of groundwater.
- Characterization of soils, groundwater and surface water.
- Sampling and chemical analysis of soils, ambient air, groundwater and surface water.
- Comparison of results of chemical analyses to the current standards.
- Confirmatory Investigation Report.
The focus of this investigation is the Suspected Contamination Areas (AS) and Potentially Contaminated Areas (AP) ascertained in the Preliminary Assessment. The analytical results indicate the existence or not of contamination.
Detailed Environmental Investigation
If the existence of an environmental impact at the site is confirmed during the Confirmatory Environmental Investigation, further studies should be undertaken to better understand and delimit the extent and seriousness of the contamination.
The objective of this work is to precisely detail the dimensions of the impact, by means of appropriate techniques such as:
- Soil borings for geological and physical-chemical characterization.
- Expansion of the grid of monitoring wells to delimit the contamination plumes.
- Monitoring of the soil gases and the ambient air.
- Geophysical assessment.
- Elimination of active sources of contamination.
- Characterization and quantification of the mass of contaminants.
- Implementation of emergency actions for environmental control.
Having the data collected in the investigation phases, the SGW Services technicians prepare a conceptual environmental model of the site and, by means of a careful assessment of the data, define the Local Environmental Diagnostic. This diagnostic serves as a base to direct the environmental remediation actions to be performed, to contain, reduce and eliminate the existing contamination.
For this, techniques may be used that encompass definition of the models of migration of contaminants in the sub-surface, definition of the level, extent and nature of any and all type of contamination detected, mathematical modeling of the flow of the groundwater and of the transportation of contaminants, assessment of associated risks, in-situ tests and detailed technical analyses to define the alternatives for elimination and/or remediation of the situations detected and their respective costs.
Mathematical Modeling of Flow and Transportation of Contaminants
The Mathematical Modeling of Flow and Transportation of Contaminants executed by SGW Services permit assessing the migration of the eventual plumes of contaminants and their future behavior, providing data for the risk assessment of risk and for the control/remediation actions.
Assessment of Toxicological Risk
Risk Assessment is the process by which risks to human health, to the environment and other assets to be protected are identified assessed and quantified. This stage of the management of contaminated areas is an efficient tool in making decisions, determining the need for intervention actions to eliminate the risks identified, and defining the remediation goals, when necessary.
SGW Services carries out Risk Assessment according to the protocols established by the Environmental Protection Agency (EPA) and by CETESB, according to the Manual for Management of Contaminated Areas, which include the stages of assessment of data, assessment of exposure, toxicological assessment and characterization of the risks. The SGW Services professionals are highly qualified and capable of critically analyzing the results of the study and directing future actions.
Qualification of Services
All the services are executed according to methodologies recommended by the environmental control agencies and technical entities, using the most advanced technologies and equipment suitable for each case, always by teams of specialized professionals.
In this phase of the project, interaction with the environmental agency is very important. SGW Services has an excellent reputation with the environmental agencies and bodies, and also carries out the entire management of the cases with these entities, negotiating the actions required and the goals to be achieved.