For the evaluation of environmental impacts, various methodologies with specific purposes have been developed. Among the best known is the Leopold Matrix, which was developed to identify the impacts of construction projects and allows estimating the importance of the detected impacts. There are other methodologies for evaluating Environmental Impacts that involve a wide range of scales and environmental criteria.
However, the purpose of this guide is its application in the field of design and implementation of an Environmental Management System (EMS), where the priority is the identification of environmental aspects and their assessment to determine their Significance and on this basis establish priorities for its control and management within the scope of the EMS. For these purposes and in order to simplify this process without obviating the necessary objectivity, we propose a reduced set of criteria for the assessment of the Significance of Environmental Aspects through the evaluation of their associated impacts and the determination of their importance that they satisfy:
• Requirement 4.3.1 of ISO 14001: 2004 regarding environmental aspects
• Be verifiable by third parties
• Have well-defined environmental scales and criteria that ensure an adequate assessment and at the same time do not suppose excessive complexity that limits its applicability by the members of an organization.
• Allow the assessment of the level of significance of environmental aspects and their associated impacts for the establishment of priorities in their management and control within the Environmental Management System, taking into account the practical importance of the existing cause-effect relationship between the aspect and environmental impact, which is that acting on the cause (aspect) can influence the effect (impact) by reducing or mitigating it,
Introduction
Usually the identification of Environmental Aspects in an organization that intends to design and implement an EMS is carried out within the framework of an Initial Environmental Review. However, in any case, the identification and subsequent evaluation of the Environmental Aspects must be based on previous studies (Environmental Diagnosis, Initial Environmental Review) that presuppose the evaluation of the current situation of the organization with respect to the environment, which includes the characterization of the environment and the organization; as well as a survey that identifies and reveals the situation of the structures, infrastructures, processes, activities, products, services, practices of the organization and of the materials, natural resources and waste that it uses and generates and of the applicable legal requirements and their compliance..It is recommended that both to carry out an Initial Environmental Review (RAI) and to identify and evaluate the environmental aspects and associated impacts, a work team be formed that, in addition to basic environmental knowledge, understands and is familiar with the processes, activities, products and services of the organization.
Hence, the objective of this work is to propose a methodology for the identification and evaluation (assessment of significance) of environmental aspects in the field of design and implementation of an Environmental Management System. With a scope in its application in the field of design and implementation of an Environmental Management System in the business sphere in the exploitation phase, when the environment where they operate and the environmental aspects of their activities do not entail such complexity that they require an assessment through other criteria and evaluation scales in addition to those used in this guide.
Development
Identification of Environmental Aspects
Identification of the inputs and outputs of the processes / activities.
The inputs and outputs of the processes and activities are identified. When identifying them, quantitative information should be collected whenever possible, which will then be useful in the evaluation phase.
For the identification of inputs and outputs it is recommended to use a diagram or table such as those shown below:
The process of identification of environmental aspects is carried out collectively by a work team and it involves specialists from the areas involved, who have sufficient experience and knowledge in the activities of the organization, so that no aspect is omitted. environmental that interacts with or has potential for it.
From the input and output elements, the environmental aspects (real, potential) within the scope of the Environmental Management System associated with processes, activities, products and services, both current, past or planned, and considering normal operating conditions, are identified. and abnormal, stop and start; as well as any reasonably foreseeable emergency situation. It is not necessary to consider each input of raw materials, materials or resources individually, they can be grouped by categories.
Environmental aspects can be identified from the fundamental groups and categories shown below:
- Consumption of raw materials and natural resources:
a) Consumption of non-hazardous raw materials.
b) Consumption of dangerous substances or products.
c) Water consumption.
d) Consumption of energy carriers (electric energy, fuels, etc.).
- Generation and discharge to the ground of waste:
a) Generation of solid waste assimilable to urban.
b) Generation of inert industrial waste.
c) Generation of hazardous waste.
- Generation of emissions into the atmosphere:
a) Gaseous emissions.
b) Smells.
c) Solids in suspension (particles, ashes, etc.).
- Generation of wastewater and discharges to land or marine waters.
- Generation of noise, vibration, thermal energy, radiation.
- Ground conditions.
- Potential and emergency situations
a) Leaks and spills.
b) Fire and / or explosion.
c) Uncontrolled accidental spills.
d) Uncontrolled accidental emissions
Assessment of the significance of the Environmental Aspects
The process of evaluation of environmental aspects is carried out collectively by the work team and it involves specialists from the areas involved, who have sufficient experience and knowledge in the activities of the entity, so that a evaluation as accurate as possible.
It is considered that changes and effects on the environment as a total or partial result of environmental aspects may be, among others, the following:
Impacts on the ground:
- Use and contamination of soils
- erosion
- deforestation
Impacts on water resources
- Contamination of ground and / or surface waters
- Acidification
- Eutrophication
Impacts on air quality
- Air pollution
- Global warming
- Depletion of the ozone layer
Other impacts:
- Depletion of natural resources (ground and / or surface water sources, non-renewable fossil fuels)
- Noise pollution
- Light pollution
- Affectations and injuries to human beings
- Impacts on fauna
- Effects on the landscape
- Impacts on flora
It is considered that the environmental factors and components affected may be:
Physical environment
- Air (Effects on air quality)
- Surface Waters (Effects on the quality of surface waters / hydraulic parameters of bodies of surface waters)
- Groundwater (Effects on groundwater quality / hydraulic parameters of groundwater bodies)
- Soils / Geomorphology (Effects on the quality / integrity of soils / geoforms)
- Biota (Affecting flora, fauna and / or ecological processes)
- Natural resources (Effects of depletion of resources).
- Perceptual (Effects on landscape heritage)
Socioeconomic environment
- Cultural Heritage (Effects on cultural, historical or testimonial heritage)
- Man / population (Effects on health and / or safety)
- Economy (Economic effects)
Once the environmental aspects of the activities, products and services that interact with the environment have been identified, the work team proceeds to evaluate them by weighing the associated environmental impacts in order to determine their importance, for which a Evaluation matrix of the environmental aspects and associated impacts of the products, activities and services of the organization as indicated in Annex A. Evaluation matrix of the environmental aspects and associated impacts.
The importance of environmental impacts is assessed according to criteria and evaluation scales as indicated in the Annex. B. Criteria and scales of evaluation and according to the matrix, which analytically expresses the result of a projection of significance of the aspects-impacts identified.
The importance value of environmental impacts is calculated through the expression:
IM = F or P x C (I + E + P + S)
Where:
IM -Importance of impact
F or P: Frequency (used when dealing with actual impacts) or Probability (used when dealing with potential impacts)
C: Consequence
The value of Consequence (C) in the formula is evaluated based on the criteria of:
I: intensity
E: Extension
Q: Persistence
S: Sensitivity
The result of said formula varies between a minimum value of 4 and a maximum of 36.
All the identified and valued environmental aspects constitute the basis for the elaboration of the organization's environmental objectives, goals and programs, their control and management is fundamental for an adequate environmental performance. The priority assigned to them for their control and management depends on the Significance range, which implies the allocation of resources and the preferential application of specific actions.
Information on environmental aspects must be documented and kept on record. Annex C. Record of Significant Environmental Aspects.
Information on environmental aspects should be regularly updated as part of the EMS review process, in order to:
- take into account new elements or improvements that may influence the significance value assigned to each aspect.
- include new aspects associated with the introduction of new technologies or changes in processes and activities.
- exclude old aspects associated with technologies, processes and activities that are no longer in force.
Annex A. Evaluation matrix of environmental aspects and associated impacts
Annex B. Evaluation criteria and scales
Annex C. Record of Significant Environmental Aspects
Bibliography consulted
• ISO 14001: 2004. Environmental management systems. Requirements with guidance for use.
• ISO 14004: 2004. Environmental Management System. General guidelines on principles, systems and support techniques.
• ISO 14031: 2001. Environmental Management. Environmental Performance Evaluation. Guidelines.
• Conesa Fernández-Vitoria, V. 2000. Methodological guide for the evaluation of the environmental impact. 3rd Ed. Mundi Press. Madrid.
• Gómez Orea, D. 2003. Environmental impact assessment. A preventive instrument for environmental management. 2nd ed. Ed. Mundi Press. Madrid.
