Sustainability,
Mining and Aquatic Ecology
INTRODUCTION
The environmental and the rehabilitation of mining operations
is a recognized aspect of worldwide production. In terms
of aquatic ecology remediation it can be a costly exercise
to correct and manage such environments and in my cases
culminate in low value in terms of economic, social or sustainable
output.
HABITATS
Generally, three particular types of habitats are formed
from mine workings:-
1.
Subsidence from underground mining operations creating typically
shallow lakes and wetland zones.
2. Planned extraction of mineral resources causing large
mine voids filling with water creating deep water ponds
and lakes.
3. Coal-mine water discharge / mine springs occurring from
old mine workings.
Subsidence
voids
Historically, the rehabilitation of industrial zones and
in particular redundant coalfield areas has been a serious
problem throughout the Western Hemisphere. In 1995, the
‘Earth Centre’ project based at South Yorkshire,
United Kingdom explored new methods of sustainable freshwater
aquaculture for applications to environmental and economic
regeneration. Mining subsidence contributed to the creation
of wetland habitats suitable for freshwater aquaculture
and constructive modifications lead to new pond construction
utilising coal spoil waste material as a semi-impermeable
membrane for the lining fish ponds. The treatment of metal
pollutants in the initial culture water was by methods of
engineered ecological filtration with the utilisation of
emergent water plants to remove contaminates from the source
water.
Excavated
voids
There are over 1,800 fresh water filled mine voids in Western
Australia. Relinquishment of final mining voids is a significant
issue for coal mining companies. The cost of rehabilitating
mine voids to land fill and re-establishment of pre-existing
terrestrial habitats is prohibitive and not considered to
be a viable commercial option by most coal mining companies.
Utilising well-managed water quality, there is a huge potential
to use these abandoned water bodies for aquaculture and
recreational fishing.
The
‘Centre for Sustainable Mine Lakes’ based in
the state is currently undergoing research in this field.
Coal-mine
water discharge
One of the most ambitious projects opened in June 2000 in West
Virginia, USA is a facility owned by the Mingo County Redevelopment
Authority. The fish hatchery makes use of an abundant yet under-used
resource—coal-mine water discharge. This semi-mature project
is currently producing commercial volumes of arctic char and rainbow
trout and estimated production capacity of 500,000 lbs annually.
RESEARCH
ISSUES
Water quality
One of the greatest issues to overcome for aquaculture suitability
is water quality. This can be achieved by an integrated water
treatment system using aeration, fluidised limestone beds, algae
ponds, reed bed filtration system and finally settling ponds.
Such systems have been proven to precipitate iron and increase
pH to optimize levels for fish production.
Food
safety
Bogoso Mines (Ghana) used an old mine pit for a pilot fish farming
project reportedly producing 2.5 tonnes of fresh tilapia and hope
to produce 10 tonnes of the freshwater fish Tilapia within the
next three years. The company states that the fish from the pond
have been tested and proved safe for consumption. Aquaculture
has developed sophisticated government food safety testing facilities
around the world. The precursor of water treatment to achieve
optimum water quality for aquaculture production serves a dual
purpose of reducing heavy metals that may contaminate fish flesh.
ADDED
VALUE
Integrated systems
By utilising using mine lake water with aquaculture this can bring
nature conservation, eco-tourism and recreation, valuable assets
towards community building exercises. Integrated aquaculture embraces
polyculture where finfish, crustaceans and hydroponics can utilise
bio-organic waste streams. Further community development will
evolve from processing and marketing of horticulture and aquaculture
products
Marketing
potential
Aquaculture has recorded an increased growth in production of
30 percent from 1998 to 2002 largely attributed to improvements
in technology. Our seafood consumption has trebled over the past
thirty years and most authorities suggest that we have reached
the limit of our catch from the oceans and expect aquaculture
to double its world production in the next ten years. The seafood
trade deficit in the US is currently estimated at $6.5 billion,
second only to petroleum in terms of natural goods greatest marketing
opportunities ever."
Algaculture
Particulary the culture of microalgaes can be performed in
current and old mine tailings dams. There is potential for producing on site
biofuels and bio-lubricants and becoming self sufficint in transport(fuel) energy.
"
REFERENCES:
Earth Centre
An
Overview of Freshwater Sustainable Aquaculture techniques on a
reclaimed coalfield site.
United Kingdom, 1995
Mining
Aquaculture’s Potential
Aquaculture Food and Marketing Development Project
West Virginia University – Agriculture & Forestry Experimental
Station
WVU Extension Aquaculture
Appalachian
Regional Commission's Area Development Program
Mining
Fresh Water for Aquaculture
Appalachia, May–August 2000
by Carl Hoffman
Mining
companies produce fish in old pits
Home Page Ghana
Centre
for Sustainable Mine Lakes(CSML)
Curtin University of Technology, University of Western Australia
Australian
Coal Association Research Program
Aquaculture
as a Relinquishment Option for Final Voids
Premier
Coal, Western Australia
Earth
Centre 1993-2004 (United Kingdom)
Innovative
remediation and centre for sustainable development
United
Nations
Food and Agriculture Organisation - State
of the World Fisheries
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