Page 59 - THE FIRE STATION

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All water (waste-water, clean water, runoff from roads) other than
rainwater must therefore be collected and disposed of off-site.
Hydrogeology
The ground beneath the LaTombe site has a Paleozoic base of
carboniferous rock, i.e. a layer more or less rich in coal.
Mainly formed during the Carboniferous Period, coal is found in
seams.Those at Charleroi are over 1500 metres thick, made up of
many formations.The coalfield’s predominantly clay formations
are not a priori favourable for storing water and forming large
reserves. Even so, a few very local sandstone pockets may contain
significant quantities of water, as revealed by a “dix-sous” probe
carried out within a radius of 1500 metres around the fire station
site which identified an underground reservoir some 1400 metres
north-west of the site, filled with water from the carboniferous
layer. It has an authorised abstraction volume of 10,000 m3 a year, The zones dominated by wasteland are the home of many species
or 27 m3 a day.
This reservoir constitutes proof that the rock does contain water
reserves, even though the presence of faults in many places splits
up the seams.
In the course of the construction work, an overflow was found in
the existing subterranean water network, passing some 10 me-
tres below the fire station.Two inspection chambers were thus
planned, one close to the sports field and the other on the ma-
noeuvring area.
Fauna and flora
In contrast to the slag heap and wet zone with their interesting
biology, the fire station site itself was of little interest as regards
flora and fauna, being the place where the backfill from the 1978
motorway construction had been dumped. However, the higher
temperature of the slag heap due to the combustion of coal resi-
dues within it has encouraged the spread of plants and animals
not usually found in the region.
More than 300 types of plants have been identified on the slag
heap, apart from mushrooms and rare lichens.
The fauna is just as varied. In the pioneer vegetation zones such
as the slag heap’s south-west flank, we find species dependent
on scree, such as the northern wheatear.
of insects, such as the swallowtail butterfly and the blue-winged
grasshopper, very rare in the region away from the slag heaps.
As for the more wooded slopes, they are home to many woodland
bird species, such as the green woodpecker, the great spotted
woodpecker and the chaffinch.
Landmarks in the countryside, the slag heaps are also stopping-off
points for migrating birds.
As for the wet zones, these offer shelter and nesting opportunities
to aquatic and semi-aquatic species such as waders, amphibians,
dragonflies and other insects.
A number of these wetland species, such as the dragonfly and
natterjack toad, are there on account of the slag heap.
Protecting the wet zones and planning for ecological corridors
between them and the slag heap were imperative to preserve
the biotope. Fencing around the site has been kept to a minimum,
only protecting facilities necessary for the fire station’s function-
ing.The rest of the site is left to the local species.Two ponds and
two “scree slopes” made of stones found when excavating the
site have been constructed to provide a habitat for small animals
and insects.