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% 830 words
% actual: 1220+ words
\section{Proposed activities and their potential effects}
All three major stations in the life cycle of the proposed dairy
factory have to be considered for an assessment of the potential
effects of the project: preparation of the site and construction,
operation, and eventual close-down of the facility. For the purposes
of this assignment only the potential impacts of the first two stages
shall be addressed as they dominate the life cycle effects. This
includes the following activities:
\begin{inparaenum}[\itshape(a)\upshape]
\item site preparation and construction work;
\item water allocation and abstraction;
\item treatment of wastes and wastewater discharge; and
\item transport of raw materials and goods.
\end{inparaenum}
The different activities at different stages may result in similar
effects on a given component of the socio-economic or physical
environment, and many impacts can cause a cascade of other effects of
varying significance. All project activities are to be evaluated
against selected components of the environment, including
\begin{inparaenum}[\itshape(a)\upshape]
\item air and atmosphere;
\item water and soil;
\item vegetation and habitat;
\item human health;
\item amenity values and cultural heritage; and
\item economic base.
\end{inparaenum}
\subsection{Overview}
The proposed dairy processing facility is supposed to be located close
to the river for easy access to water and for the convenient discharge
of wastewater back into the river. The preparation of the site for
construction in proximity to the river as well as the proposed take
and discharge activities during operation of the factory have direct
effects on water quality parameters. Changes to the properties of the
body of water (e.g. sediment load, changes in flow patterns, increases
in nutrient levels) affect not merely aesthetic values held by
residents of the affected region, but are likely to have impacts on
the composition of aquatic communities and the health of riparian and
aquatic ecosystems.
Major impacts on air quality and amenity values are the emission of
particulate matter, gases and odours, generation of noise (during
construction and transport of products and raw materials), and `visual
pollution' (e.g. smokestacks and a factory building in the landscape).
\subsection{Construction}
Preparing the selected site for construction requires the displacement
of existing uses. On a site close to the river in a rural area, the
site may be populated by riparian vegetation. Vegetation in the
riparian area and the adjoining uplands may serve as a filter,
reducing the amount of sediment, excess nutrients and other pollutants
entering the river \parencite{riparian}. This filtering ability is
particularly valuable in a region where dairy farming is expanding and
with it the cumulative impact of non-point sources of farm effluent is
increasing. The clearing of vegetation may also directly reduce
available habitat for native species, such as frogs and insects with
aquatic larvae \parencite{riparian-management}. This impact can mostly
be avoided by selecting a site that has already been cleared and does
not serve as important habitat to native species.
During dredging and excavation works on the construction site or
during the removal of sediments away from the site, sediments may
spill into nearby water bodies. An excessive increase in suspended
sediments in the river affects water clarity, thereby reducing
penetration with sunlight which is needed by aquatic plants and algae
to grow. Increased turbidity may also make it difficult for fish to
find food or detect predators \parencite{niwa-freshwater}. As the
sediment load of a river increases, its flow characteristics change
making the conditions less favourable for certain aquatic species and
invertebrate habitat may be destroyed by smothering animals, plants
and the river-bed. Sedimentation is less of a problem when the
construction site and the transport routes are chosen to be not in the
immediate vicinity of the river or other bodies of water.
\subsection{Effects during operation}
During operation of the dairy factory water is abstracted from the
nearby river to sustain the processing activities. The amount of water
that is used by a dairy factory depends on a variety on parameters,
including the range of products that the factory produces and the
operations that are involved in production; in New Zealand about 2.2
litres of water are used for every litre of milk that is being
processed \parencite[Fonterra data, cited
in][]{vanasselt}\footnote{When dairy farming is included in the
calculations, one litre of milk requires almost 1,000 litres of water
on average.}. According to \textcite{vanasselt}, dairy processing
plants use water mainly for cleaning and sanitising operations, as
well as heating and cooling.
The \textcite[][p. 110]{growing} summarises the potential impacts of
water take as follows:
\begin{quote}
The environmental effects of water allocation are twofold – the
effects of the reduction of water in the water bodies and the
effects the use of that water may have on water quality.
Abstraction of water from surface water or groundwater, will have an
impact on the ecosystems reliant on that water, for example, by
reducing the flow of a river, or increasing the temperature of the
water. Thus a reduced flow may mean that the river is no longer a
suitable habitat or breeding ground for a type of fish.
\end{quote}
The major waste material from processing milk in a dairy factory is
wastewater carrying organic components (such as proteins, lactose and
fat) and inorganic components (e.g. nutrients). Wastewater includes
both water that has been removed from the milk and abstracted water
that has been used to sanitise equipment, clean the factory, or for
heating and cooling. When organic components in dairy factory
effluent reach rivers they are converted to carbon dioxide and water
by bacteria under use of oxygen. Whether the inflow of organic
components leads to oxygen depletion with fatal consequences for fish
and other members of aquatic communities depends on the re-aeriation
characteristics of the river \parencite{chemical}. Farming practices
also influence the contents of the factory's wastewater. Residual
antibiotics given to cattle and remains of pesticides that were
applied to the feed crops tend to accumulate in the milk and end up in
the wastewater after processing; upon discharge these trace amounts
enter the food web. Contamination of the river water may make the
water unfit for recreational use, even kilometres away from the
discharge site.
According to \textcite{vanasselt}, milk is repeatedly heated and
cooled during its way through the factory. UHT (ulta-high temperature)
treatment and other processes used to kill off harmful bacteria in the
milk, for example, results in heated wastewater. As most aquatic
ecosystems are very sensitive to temperature, discharges of warm
wastewater could significantly affect the composition and dynamics of
aquatic communities around the discharge location; hence, wastewater
discharges are usually required not to alter the natural temperature
of the sink waterway by more than one to two
degrees \parencite{chemical}.
\subsection{Other activities and socio-economic effects}
Related activities such as the transport of raw materials from farms
to the factory and the transport of finished products to local stores
and export sites bring about a chain of higher-order effects, such as
an increase in the use of fossil fuels and an increase in noise
levels. Regular transportation with heavy vehicles puts additional
stress on roads, requiring more maintenance work. A greater demand in
social services for workers who move to the area to work at the
factory may also stress the community's budget. All of the above
effects could lead to a reduction of life quality for residents in
this area.
The inventory of impacts does not end here, however. The potentially
beneficial effects of the proposed project also have to be considered
and---if possible---quantified. The establishment of a dairy factory
close to dairy farms provides a boost to the local and national
economy and creates numerous job opportunities---temporary jobs for
construction workers as well as stable employment for engineers,
maintenance personnel, factory workers, managers, and in the
transportation sector.
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