|
2.10 Pressures on the environment
The EnTA procedures described in this Manual addresses the major
sources of environmental pressures normally associated with the different
components of a technology (see Figure 4). A brief description of these
components and the associated pressures is provided below.
Resource use
This category includes all of the material, water, energy, and
land resources required to establish the technology and to produce the desired
outputs (e.g. services or products). Included in this category are all of the
inputs to a process, as well as the support requirements (e.g. buildings, and
land). Particular attention should be paid to identification of all toxic,
non-renewable and scarce materials used by the technology.
Wastes and products
This category includes all of the gaseous, liquid and solid
wastes, and noise, produced by the technology. These are often the major source
of environmental pressures. This category also includes the products produced by
the technology, with attention being given to those that have the potential to
cause significant pressures on environmental systems - for instance toxic
substances (e.g. pesticides that have the potential for accidental release into
the environment during storage or transportation).
Figure 4. Components of a technological system
Human resources
The human resources category includes all the labour
requirements needed to build, maintain, operate and eventually decommission the
technology. Of special interest in this category is the number of people that
may need to be recruited from outside the locality where the technology will be
used. A large influx of labour can make significant demands upon the
environment, resources, infrastructure and social cohesion, and on support
services, especially in a small community.
Infrastructure
The infrastructure category includes all of the supporting
facilities, services and utilities needed by the technology. This might include
roads, public transportation services and sewers. In this category it is
important to give full consideration to the pressures arising from
infrastructure changes that relate directly to introduction of the technology.
In other words, the incremental and cumulative pressures that result from adding
new, or expanding existing, infrastructure are considered at this stage in the
EnTA.
Supporting Technologies
Technology interventions often require other supporting
technologies in order to operate effectively. Examples include storage
facilities and waste treatment plants. These supporting technologies place
additional demands on the environment, due to such effects as resource
consumption and waste emissions. The resulting pressures need to be considered
if the total environmental burden of a technology investment is to be fully
characterised. As with the infrastructure pressures, it is especially important
to incorporate the supporting technologies that will be introduced or used as a
direct consequence of the proposed technology intervention.
2.11 Boundaries for the pressures associated
with the technology
Each of the pressures associated with the technology will have
its own life cycle. For example, at any stage of this life cycle the use of a
resource, or production of a waste, may have a significant impact upon the
environment.
Ideally the full life cycle of the technology intervention
should be assessed - from initial concept, through design, development,
procurement, operation and modification, to replacement, decommissioning or
disposal. While this appears to escalate the complexity and demands of the
assessment, absence of a long-term view can sometimes mean that a technology
considered to be environmentally friendly in the first instance can become a
significant burden on the environment some time later in its life.
It may be possible and appropriate to restrict the spatial extent of the
assessment. Concerns might focus on the pressures the technology could impose on
the local community, or on environmental and related systems within the national
boundaries. While imposing such spatial limits may be expedient, decisions to
limit the spatial scope of an assessment should be made only after careful
consideration, and in consultation with all relevant stakeholders.
As a further example, when considering the use of a toxic chemical in an
industrial process, thought should be given to the potential for this chemical
to spill or leak during either its production, transportation, storage or
intended use. Similarly, the effects of a waste produced by the technology
should be considered from the time it is generated at least to the time of final
disposal, and often beyond that. In general, there are four main phases that
should considered in an EnTA:
- Transportation: The transportation of resources to the technology, or
the wastes from it;
- Storage: The storage of resources and wastes prior to use or
disposal;
- Use: The way the resources are used in the process, including
handling; and
- Disposal: The various environmental pathways and final disposal sites
of the wastes produced by the technology.
| 
