has been zoned based on the sensitivity to air pollution and water pollution.
High/medium/low Risk zones have been arrived at considering pollution
receiving potential of the sites. The maps Prepared in the previous sections
show the following zones: sensitive zones;
risk zones for air polluting industries (Am);
risk zones for air polluting industries (AI);
risk zones for surface water polluting industries (Wh); and
risk zones for surface water polluting industries (Wm).
Combining the above maps, sites available for various types of industries
have been arrived at. The outcome is sites showing risks due to siting
of industries with air and water pollution. In the sensitive zones, no
industrial siting can be done. Of the other areas, the following nine
combinations of sites/zones are possible that are considered for industrial
AhWh AhWm AhWI
AmWh AmWm AmWI
AlWh AlWm AIWI
To determine the industries suitable for these zones, the pollution generation
potential of the industries areclassified, based on the pollution generated,
A) Air Polluting Industries
Air polluting industries are those, which emit any solid, liquid, or gaseous
substances into the atmosphere in such concentrations as may be or Tend
to be injurious to human beings or other livingcreatures or plants or
property or environment. They are further classified as below:
Industries with emissions from combustion of fuels using coal >125
t/hr or equivalent fuel or industries having process emissions emitted
through organized let out system (stack) or having fugitive emissions
or odour nuisance or industries generating noise levels> 90 dBA
Industries with combustion emissions from usage of coal < 125 t/hr
or equivalent or generating noise
Levels between 70-69 dBA or having DG sets>50KVA
Industries having emissions only from boilers of steam generation capacity
less than 2t/hr but not using coal or noise of <70 dBA or using DG
sets up to 50KVA
B)Water Polluting Industries
Water polluting industries are those which contaminate or are likely to
contaminate or alter the physical, chemical or biological properties of
water or discharge any sewage or trade effluent or any other liquid, such
water harmful or injurious to public health or safety, or to domestic,
commercial, industrial, agricultural or other legitimate uses, or to the
life and health of animals or plants or of aquatic organisms.
Industries generate wastewater of inorganic nature or organic waste of
not easily biodegradable or toxic nature or combination of all.
Industries generating wastewater, which is easily biodegradable and non-toxic,
industries generating slurries and high temperature effluent
Industries with wastewater form domestic use/cooling or boiler blow down
(having no temperature variation and metals or other contaminants) or
generating no wastewater or industries with complete recycling system/reutilization
with 'zero' discharge.
C) Solid Waste Generating Industries
Industries that generate solid waste and hazardous waste are classified
as solid waste generating industries. They are further classified as below:
industries generating hazardous waste and as defined under rule 3(i),
3(n) and 4 of the Hazardous Waste Management and- Handling Rules,1989
Industries generating inorganic and organic compostable waste and all
wastes with leachate potential.
Industries generating solid waste of inert nature or no waste or with
all the above cases, the pollution generating potential of an Industry
is taken into consideration. An Industry generating wastewater that may
be treated to the required standards by providing an elaborate treatment
system is still considered as water polluting industry. An industry, only
if it adopts clean technology so as to avoid any generation of wastewater,
may be said to be non-water-polluting industry.
An industry may be a combination of A1, W1 and 81 or A1, W2, S3 and so
on. For example, an industry may be relevant only from water pollution
and may not be relevant from air pollution and solid waste generation.
Based on the nature of air pollution and water pollution potential and
solid waste generation, 27 combinations of industries as below are possible:
A1W1S1 A1W1S2 A1W1S3 A2W1S1
A2W1S2 A2W1S3 A1W2S1 A1 W2S3
A1 W2S3 A1 W3 S1 A1 W2 S2 A1 W3S1
A3 W1 S1 A3 W1 S2 A3 W1 S3 A2 W2 S2
A2 W2 S1 A2 W2 S1 A2W2 S3 A2 W3 S2
A2 W3 S3 A3 W1 S2 A3 W2 S2 A2 W2 S3
A3 W3S1 A3 W3 S2 A3 W3 S3
on above classification, recommendations on risks involved in locating
industries in various zones as given below.
i)The "Sensitive Zones" Map are unsuitable for industrial siting
owing to legal restriction
ii) The map showing risks due to siting of air polluting industries shows
the risks involved in - locating air polluting industries in various zones.
The 'high' risks areas are very sensitive to air pollution and hence air
polluting Industries in various zones.The 'high' risks areas are very
sensitive to air pollution and hence air polluting industries should not
be allowed in these zones. However, based on micro-level studies, siting
of only very small air polluting industries (A3 category) may be considered
in these areas. The 'medium' risks areas are unsuitable for highly (air)
polluting industries (A 1 category), but in these zones siting of medium
and low polluting industries(A2/A3 category)whose impact is not likely
to exceed 2km may be considered .
The 'low' risk areas may be considered for all types of air polluting
industries (A1/A2/A3 category). However, the industries with very high
pollution potential and whose impact is likely to exceed 5km are to be
reviewed individually even in the low risk zones.
iii) The map showing risks due to siting surface water polluting industries
(Map 18) shows risks involved in locating water polluting industries and
discharging effluents into surface water. Tripura has 'high', 'medium',
and 'low' risk zones. The high-risk areas are very sensitive to water
pollution and hence no water polluting industry should be allowed in these
areas. However, based on micro-level studies, siting of very low (water)
polluting industries (W3 category) may be considered. The medium risks
areas may be considered for medium water polluting industries (W2/W3)
whose effluents are easily bio-degradable and are non toxic. There is
no low risk area in the Tripura, and hence is not suitable for siting
of industries with high water pollution potential (W1 categories).
iv) The risks due to siting of groundwater polluting activities are shown
in (Map 24). The high-risk areas are very sensitive to groundwater pollution
and hence, disposal of effluents or solid/hazardous waste on land should
not be allowed. The medium risk areas may be considered for controlled
and limited discharges of only easily biodegradable and non-toxic effluents.
In 'low' risk areas, the discharge of toxic or not easily bio-degradable
effluents and disposal of hazardous waste can be allowed. Hazardous waste
should either be incinerated or disposed in suitable areas. Organic compostable
waste disposal may be allowed in medium risk zones. Inert solid waste
may be disposed even in high-risk areas based on micro-level-studies
v) Five types of zones are identified which may be considered for siting
different categories of polluting industries. These zones are scattered
in different parts of the state and divided into five groups as given
1) Zones for low air and low water polluting
The zones marked 'AhWh'in the Suitability map are suitable only for non-polluting
or very low polluting industries. These zones are present in the sub-divisions
of Sadar, Bishalgarh, Khowai and Sonamura in the West Tripura District,
the sub-divisions of Sa broom , Belonia, Udaipur, Amarpur under South
Tripura District, the sub-divisions of Kamalpur under Dhalai District
and the sub-division of. Dharmanagar under North Tripura District and
a few small areas scattered through out the state.
2) Zones for low air and medium water polluting
The zones marked' AhWm' in the Suitability map may be considered only
for industries having no air pollution potential (A3 category) and/or
medium or low water pollution potential (W2/W3 category).
These zones are falling mostly under Charipara and Pratapgarh near Agartala,
some parts of Jirania, Champaknagar under Sadar sub-division; Uttar Padmabil,
Paschim Bellchhara, Paschim Singichhara or Khowai sub division; Chhataria;
Tepania of Udaipur sub division; Manu under Longtarai Valley Subdivision;
Damchhara under Kanchanpur sub-division and some parts of Kailashahar
(Suitable for A3W2 & A3W3 only).
3) Zones for low air and medium water polluting
The zones marked' AmWh' in the Suitability map may be considered only
for industries having medium or low air pollution potential (A2/A3 category)
and/or low water pollution potential (W3 category)
Lakshmilunga, Fatikchhara, Bijoynagar, Kalamchhara, Mohanpur under Sadar
sub-division; Banbazar,Asarambari and a few scattered places under Khowai
sub-division and Dolubari under Sabroom sub-division falls under this
zone (suitable for A3W2 & A3W3 only).
Medium Air and Medium water Polluting Industries( AmWm)
The zones marked' AmWm' in the Suitability map may be considered only
for industries having medium or low air pollution potential (A2/A3 category)
and/or medium or low water pollution potential (W2/W3 categorised under
this zone (Suitable for A2W2, A3W2, A2W3 and A3W3 only).
5) All Air and Low Water Polluting Industries-(AIWh):
The zones marked' AIWh' in the Suitability map may be considered only
for industries having high or medium or low air pollution potential (A1/A2/A3
category) and/or low water pollution potential (W3 category). Bamutia
and Narsingarh are under Sadar Sub-division of the West Tripura District
constitute this zone (Suitable for A1W3, A2W3 & A3W3 only).
vi) In view of the limited water pollution receiving potential and drought
prone nature of the state, the industries with high water pollution generation
potential (W1 categories) should be restricted from siting in the state.
vii) For siting of industries in or in the immediate vicinity of the urban
areas/settlements, the above recommendation do not apply even if they
fall under zones found to be suitable for industrial siting. Detailed
micro-level studies are to be carried out in these areas to find out the
site suitability taking into consideration population density, distribution
of density, and transportation of chemicals/hazardous waste. Only after
such detailed micro-level studies are conducted, decisions regarding siting
of industries should be taken.
viii) The industries with very low pollution potential may be considered
for siting anywhere in the state.
The guidelines for deciding on the site for these industries are given
industries/operation/processes should- not discharge wastewater-or:-emissions
hazardous waste and should not be involved in handling toxic/hazardous
chemicals as scheduled in the Environmental (Protection) Act, 1986.
They should not have any operations or processes that can be or likely
to cause pollution.
with number of workers more than five (5) and power load of more than
1 kw should not be allowed in residential areas. Other industries (workers:
<5, power: < 1 kw) of household nature may come up in residential
areas but only in the ground floor.
and service centers with work force of less than twenty(20)and power
load of less than 5kw may be allowed in the district centres or service
centres or flatted industrial complexes, if proper buffer zones are
provided to the residential land use.
chakki, dal grind and grinders that are needed close to residential
neighborhoods may be permitted in local shopping areas, but they should
not have more than five (5) workers or 6 kw power.
industry with twenty (20) or more workers should be located only in
the suitable zones for industries identified in the Atlas.
ix) The existing industries if are located in sites
that are found to be unsuitable as per the present Atlas, further evaluations
are to be made and if necessary, stringent standards are to be achieved
and the industries are to provide more elaborate pollution control systems.
x) Industries in small scale sector that are dependent on rural areas
or are agro/forest based, viz. rice mills,manufacture of agricultural
implements,chilling plants and cold storage ,saw mills etc may be considered
in areas other than the identified industrial zones, even in prime agricultural
lands ('very high' or 'high' agricultural use) based on micro-level studies.