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Environment
Urban Centers or
Aquariums!
by VK
Joshi
One might
wonder what our urban centers have to do with aquariums! Well yes there
is no commonality between the two, yet there is a major problem which
plagues the both. It is the problem of disposal of solid waste. Those
who rear fishes in aquariums know that if ammonia generated through
their poop is not properly managed, the fishes die. Congested human
agglomerates are facing the same problem in India today.
The generation of solid waste started the day humans changed their
life-style from a hunter-gatherer to cultivator. As long as they were
wandering about, like animals, whatever waste they generated must have
been strewn over the area of their territory or the area they traversed.
The problem of waste started, once the settlements came up.
'During the flourishing civilizations from 300 to 1000 BC, solid waste
was placed in large pits with a layer of soil cover', say Amar M. Dhere
of Department of Environmental Science, Indira College of Commerce and
Science, Pune and his co-researchers from Sangola College, Sangola,
Department of Geography, SM College, Akluj and CESJ & HD, Yashada, Pune,
Maharashtra. These researchers made a detailed study of the problem of
solid waste management in Pune city and its impact on air and
groundwater quality. The outcome of their research was published in
September, 2008 issue of Current Science.
 As the human communities flourished, the need to manage the waste,
cleanliness of the settlements etc became imperative. Thus came the
municipalities and the waste generated in the communities was termed as
municipal waste. It is broadly of two types: the human excreta and the
municipal solid waste. Dhere and his co-workers have carried out
detailed study of the disposal of the municipal solid waste (MSW) and
the after effects thereof.
The quantity of MSW produced daily in the form of paper, plastic, rag,
metal, glass pieces, ash, scrap materials, waste papers, dead animals,
discarded chemicals, paints, hazardous hospital waste, agricultural
waste and compostable matter is gargantuan. Sad part is that the entire
range of MSW is disposed off with the centuries old tradition of dumping
it in depressions/landfills and covered with layers of soil cover. This
procedure is also applied to the hospital or the bio-medical waste.
Solid waste generation in Indian cities is on the increase say Dhere and
his colleagues. It has increased from an average per capita generation
of 0.32/kg in 1971-73 to 0.48/kg/day in 1994. The figures have grown
exponentially since then. Daily per capita generation of MSW ranges from
100 g in small towns to 500 g in large towns, say Dhere et al. A study
conducted by NEERI, Nagpur on the MSW contents shows that major chunk is
composed of 30-40% organic matter and 30-40% ash and fine earth, paper
3-6%, while plastic, glass and metal each is less than 1%.
 Since quite a bit of MSW contains organic matter, dumping it in the
traditional landfills is nothing but an open invitation to birds,
rodents and pests like fleas, for whom it is an attractive source for
food. Microbes are present everywhere and they cause degradation of most
of the solid waste. These get degraded to carbon dioxide and methane.
Dhere et al report that Methane gas constitutes about 60% of a landfill.
It is needless to emphasize here that Methane Gas is one of the worst
atmospheric pollutants. Haphazard and unscientific disposal of solid
waste leads to augmentation in atmospheric carbon dioxide and methane,
which are the major cause of global warming some people believe.
Microbial degradation of MSW aided by water leads to formation of a
liquid termed leachate. It has high organic content, soluble salts and
other pollutants which ultimately render the groundwater unfit for
drinking. Recently, NEERI conducted a study of MSW dumped on the right
bank of Gomti River at Lucknow to create a high ground for a memorial
being erected by the government. As per the report the leachate from the
dump has already polluted the river and groundwater too is threatened by
pollution. Water polluted by leachates causes jaundice, nausea, asthma
etc. It can even cause miscarriage and infertility.
Pune municipality produces about 1000 to 1200 metric tones of solid
waste per day. Un-segregated MSW is carried and dumped at a landfill site
near Urali-Devach village. The landfill has an area of about 43 hectares
(ha), out of which about 15 ha is already filled up and sealed off
permanently. Though the municipal authorities use state of art
biological decomposition method for the waste, but the Extra Molecular (EM)
culture used on the waste can not treat the un-segregated waste fully.
The procedure used is excellent for organic waste only, it can not
tackle the other types of wastes. Thus out of 1000-1200 metric tons of
waste only 150 metric tones of waste is decomposed everyday and used as
manure.
The remaining waste in the landfill is often burnt and clouds of heavy
smoke result in respiratory problems for the villagers. Do we care?
Similarly, the leachates have changed the composition of ground water
from safe and potable to unsafe and contaminated. The process has been
going on since 1983.
Come April and the heat causes methane in organic solid waste to burn
and for three months Urali-Devach is covered under a pall of smoke with
suspended particle matter (SPM) much higher (average annual being 1708.3
�g/metre cube of atmosphere) than the norms laid by the Central
Pollution Control Board (CPCB). Inhalation of 0.1 to 100 �g SPM is
enough to cause asthma and other respiratory diseases. All to all the
air quality of Urali-Devach is bad. Similarly, average annual emission
of sulphur dioxide and nitrous oxide as worked out by Dhere and his
co-workers is 35% higher than the prescribed limits set by the CPCB.
Both of these gases are known to cause lung disorders and in the present
case, the most vulnerable are the residents of Urali-Devach, rag pickers
and the truck drivers passing through the highway. They have to pay for
the health of Pune residents with their health!
The leachate generated by the MSW dump is highly acidic and corrosive.
It adds to the miseries of the residents as it percolates down to ground
water and has already contaminated the resource. Tests conducted by
Dhere et al have proved that ground water up to 800 metre from the dump
site has been affected by the contamination from leachates.
Urali-Devach village, because of uncontrolled dumping of MSW is
virtually sitting on a 'time bomb'. With air and ground water already
heavily contaminated, it is time that the authorities concerned take up
more scientific method of waste disposal. It includes three Rs say Dhere
et al. That is reduce, reuse and recycle the waste. Segregation of
bio-degradable and non-biodegradable waste at household level at Pune
can considerably reduce the problem of decomposition of organic waste.
It is easy to convert it in to manure or even generate electricity out
of it, rather than just dumping it out of sight and making lives of
villagers miserable. In fact waste to energy facilities though only 600
in numbers all over the world, are one the best ways to tackle the
problem of solid waste.
If nothing works then at least the Pune Municipality can use to
conventional and time tested method of covering the daily waste dumped
in the landfill with a minimum 15 cm thick layer of soil and every week
cover the matter with a 60 cm thick layer of soil and then compact the
layers, before further addition of waste. This checks the formation of
leachates and foul odor.
The Municipality at Pune can at least boast of a landfill and take pride
of dumping the MSW there. In most of other densely populated cities even
this facility is not available. It is a pity that the MSW is dumped in
natural depressions, which were earlier lakes and compacted to make land
for apartments. And even worse is disposing the MSW discreetly on the
outskirts of habitats.
Let's not convert our urban centers in to aquariums and suffocate under
our own muck!
November 9, 2008
Images:
1. Let's not make our cities aquariums.
2. Highly toxic leachate, MSW disposal site of Pune Municipality
3. Leachate up to 800 m away from the site is polluted.
(Image1 by the author; Images2-3, courtesy Editor Current Science,
Bangalore, India)
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