| Last Updated:: 29/04/2022

Industrial Pollution

Any form of pollution that can trace its immediate source to industrial practices is known as industrial pollution. Industrial pollution takes on many faces. It contaminates many sources of drinking water, releases unwanted toxins into the air and reduces the quality of soil all over the world.

Comprehensive Environmental Pollution Index (CEPI)

The Central Pollution Control Board developed an approach to classify industrial areas based on CEPI scores with an objective to prioritize for improving the environmental quality in these areas, in 2009.

CEPI is a rational no., which ranges between 0-100 and captures overall quality of the environment covering Air, Water and Land by following algorithm of pollution Sources, Pathways and Receptors, is calculated using the following formula:
CEPI = imax + [(100 – imax) × (i2/100) × (i3/100)]
Where, imax = maximum index (which may be Air EPI or Surface Water EPI or Groundwater EPI); and, i2 and i3 are indices for other media

Based on CEPI scores, Industrial Areas are classified as below:

S. No. CEPI Scores Categorisation of Industrial Areas
1 70 and above Critically Polluted Areas (CPAs)
2 Between 60 -70 Severely Polluted Areas (SPAs)
3 Less than 60 Other Polluted Areas (OPAs)

CPCB evaluated CEPI scores of 88 industrial clusters across the country, in 2009 and 43 industrial clusters in 17 states were identified as Critically Polluted Areas (CPAs).

SPCBs/PCCs prepared and implemented time bound action plans for improvement of environmental quality in CPAs.

CPCB continued CEPI monitoring of 43 CPAs during 2011 and 2013, also.

In CEPI evaluation during 2018, following revised CEPI-2016 methodology, 100 Industrial Areas were monitored. Out of 100 Industrial Areas, 38 Industrial Areas were identified as CPAs and 31 were identified as SPAs.

The effective implementation of action plans prepared by SPCBs/PCCs for CPAs/SPAs is carried out by concerned stakeholders and district/state level committees are constituted to review the progress of implementation of action plans.

Parameters for Monitoring

CEPI score assessment is carried out by environmental quality monitoring of ambient air, surface water and groundwater. Three rounds of monitoring at all the identified locations is being carried out with a gap of atleast one day.

A. Ambient Air Quality Monitoring for following parameters:

  1. SO2 , NO2 , PM10 , PM2.5, Lead and Ammonia (for 24 hourly average monitoring values )

  2. O3 , CO (for 1 hourly average and 8 hourly average )

  3. Benzene, Benzo(a) Pyrene, Arsenic & Nickel (for 24 hourly average value)

B. Water Quality data of

  1. Prominent Surface Water bodies such as outfalls of CETPs, ETPs, FETP, treated effluent drainage, river, canal, ponds, lakes and other such water supply resources flowing through the area or flowing adjoining the Industrial Area.

  2. Ground Water Quality data of prominent ground water resources such as observation wells of Central Ground Water Board, drinking water wells, hand pumps, bore wells and other such water supply resources located in the industrial cluster/ area under consideration or in the peripheral areas.

C. Basic water quality requirements (for surface water and ground water both) are as follows:

  1. Simple Parameters - Sanitary Survey, General Appearance, Color, Smell, Transparency and Ecological* (presence of animals like fish, insects etc. only in case of surface water bodies)

  2. Regular Monitoring Parameters - pH, O&G, Suspended Solids in mg/l, DO (% saturation), COD in mg/l, BOD in mg/l, Electrical Conductivity in µmhos/cm, Total Dissolved Solids, Nitrite–Nitrogen, Nitrate-Nitrogen, (NO2+NO3) total nitrogen in mg/l, Free Ammonia, Total residual chlorine, cyanide, fluoride, chloride, sulphate, sulphides, total hardness, dissolved phosphates, SAR, Total coliforms, Fecal Coliform (MPN/100 ml),

  3. Special Parameters - Total phosphorous, TKN, Total Ammonia(NH4+NH3)-Nitrogen, Phenols, Surface Active Agents, Anionic detergents, Organo-chlorine pesticides, PAH, PCB and PCT, Zinc, Nickel, Copper, Hexa-valent chromium, Chromium (Total), Arsenic (Total), Lead, Cadmium, Mercury, manganese, iron, vanadium, selenium, boron.

  4. Bio-assay (zebra Fish) Test - For specified samples only

Note :

  • DO is not applicable in case of ground waters.
  • DO in eutrophicated waters should include measurements for diurnal variations.
  • Static Bio-assay method may be adopt

D. Frequency of Monitoring : Environmental quality monitoring shall be undertaken by concerned SPCBs on half-yearly basis and data will be placed in the public domain:

Season Period of monitoring
Pre-monsoon April-June
Post-monsoon Dec.-Feb.





Revised Concept of Comprehensive Environmental Pollution Index (CEPI)

The concept of Comprehensive Environmental Pollution Index (CEPI) was evolved by Central Pollution Control Board (CPCB) during 2009-10 as a tool for comprehensive environmental assessment of prominent industrial clusters and formulation of remedial Action Plans for the identified critically polluted areas. Later-on proposals were received from the SPCBs, State Governments, and Industrial Associations and concerned Stake-holders for revisiting the criteria of assessment under CEPI concept. After careful examination and consideration of the suggestions of concerned stake-holders, it was decided to prepare the revised concept of CEPI by eliminating the subjective factors but retaining the factors which can be measured precisely.

To overcome the subjectivity, revised concept is proposed by eliminating the subjective factors present in earlier defined CEPI methodology, but retaining the factors which can be measured precisely. The outlines of the revised CEPI criteria are as follows:

Revised concept is prepared by eliminating the above debatable factors but retaining the factors which can be measured precisely.
It is decided to develop the Comprehensive Environmental Pollution Index (CEPI) retaining the existing algorithm of Source, Pathway and Receptor.
It is proposed to develop the Comprehensive Environmental Pollution Index (CEPI) based on Sources of pollution, real time observed values of the pollutants in the ambient air, surface water and ground water in & around the industrial cluster and health related statistics.
For assessment of the environmental quality of the area i.e. CEPI score, the concept of SNLF i.e. a surrogate number which represents the level of exposure (a function of percentage sample exceedance & Exceedance Factor) shall be used.
Health component to be evaluated based on the health data available from major hospitals in the area was also retained in the revised concept.
The monitoring data shall be analysed for the parameters exceeding the prescribed norms and time targeted remedial action plans be formulated by concerned SPCBs for the same.

Categorization of Industrial Sectors under Red, Orange, Green, and White Category

The application of this concept is not only for the purpose of location of industries, but also for the purpose of Consent management and formulation of norms related to surveillance / inspection of industries. In order to harmonize the ‘Criteria of categorization’, Directions were issued by CPCB under Section 18(1)(b) of the Water ( Prevention & Control of Pollution) , Act, 1974 to all SPCBs/PCCs to maintain uniformity in categorization of industries as red, green and orange as per list finalized by CPCB, which identified 85 types of industrial sectors as ‘Red’, 73 industrial sectors as ‘Orange’ and 86 sectors as ‘Green’.

The process of categorization thus far was primarily based on the size of the industries and consumption of resources. The pollution due to discharge of emissions & effluents and its likely impact on health was not considered as primary criteria. Accordingly, the issue was discussed thoroughly during the national level conference of the Environment Ministers of the States, held in New Delhi during April 06-07, 2015 and a ‘Working Group’ comprising of the members from CPCB, APPCB, TNPCB, WBPCB, PPCB, MPPCB and Maharashtra PCB is constituted to revisit the criteria of categorization of industries and recommend measures for making the system transparent and rational.

The Working Group has developed the criteria of categorization of industrial sectors based on the Pollution Index which is a function of the emissions (air pollutants), effluents (water pollutants), hazardous wastes generated and consumption of resources. Based on the series of brain storming sessions among CPCB, SPCBs and MoEFCC , the following criteria on ‘Range of Pollution Index ‘for the purpose of categorization of industrial sectors is finalized.

Industrial Sectors having Pollution Index score of 60 and above – Red category
Industrial Sectors having Pollution Index score of 41 to 59 – Orange category
Industrial Sectors having Pollution Index score of 21 to 40 – Green category
Industrial Sectors having Pollution Index score incl.& upto 20 - White category

The salient features of the ‘Re-categorization’ Exercise are as follows :
The Red category of industrial sectors would be 60.
The Orange category of industrial sectors would be 83.
The Green category of industrial sectors would be 63.
Newly introduced White category contains 36 industrial sectors which are practically non-polluting. There shall be no necessity of obtaining the Consent to Operate’’ for White category of industries. An intimation to concerned SPCB / PCC shall suffice. No Red category of industries shall normally be permitted in the ecologically fragile area / protected area.

The purpose of categorization is to ensure that the industry is established in a manner which is consistent with the environmental objectives. The new criteria will prompt industrial sectors willing to adopt cleaner technologies, ultimately resulting in generation of fewer pollutants. Another feature of the new categorization system lies in facilitating self-assessment by industries as the subjectivity of earlier assessment has been eliminated. This ‘Re-categorization’ is a part of the efforts, policies and objective of present government to create a clean & transparent working environment in the country and promote the Ease of Doing Business.

Environment Ministry releases new categorisation of industries

The Minister of State for Environment, Forest and Climate Change (Independent Charge), Mr Prakash Javadekar releasing the New Categorisation of Industries, in New Delhi on March 05, 2016.

(Image Source: www.biovoicenews.com/govt-releases-new-categorisation-of-industries/)

Read News: Environment Ministry releases new categorisation of industries
(Source: Press Information Bureau,Government of India,Ministry of Environment, Forests & Climate Change)

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