The Central Pollution Control Board (CPCB) has relaxed standards for upcoming sewage treatment plants (STP), including those to come up on extremely polluted stretches of the Ganga.
- Existing laws permit Biochemical oxygen demand (Bod) upto 30 mg/litre.
- Biochemical oxygen demand (BOD), (also called biological oxygen demand) is the amount of dissolved oxygen needed by aerobic biological organisms to break down organic material present in a given water sample at certain temperature over a specific time period. The BOD can be used as gauge of the effectiveness of wastewater treatment plants.
- Government’s Rs 20,000 crore push to clean the river Ganga was a 2015 proposal to have higher standards for STPs.
- Biochemical oxygen demand (Bod) – a marker for organic pollutants in the treated water had to be no more than 10 mg/litre.
- However, the Union Environment Ministry’s recent notice has junked the 10 mg/litre target. It says that STPs coming up after June 2019-except in major State capitals and metropolitan cities –need only conform to 30 mg/litre of BoD.
- These include proposed STPs to treat sewage in stretches of the river downstream of Haridwar, including Kanpur and Allahabad in UP.
- New STPs in State capitals have to cap BoD at 20mg/litre.
Problems of waste disposal in India:
- Lack of sewage treatment plants.
- Increasing urban population.
- The use of treated sewage in irrigation was emphasised in the Water (Prevention and Control of Pollution) Act 1974; however, the State Governments have failed to recognize its importance.
- It is a matter of grave concern that due attention is not paid to operation and maintenance of existing sewage treatment facilities by State Governments.
- In spite of the urgencies of saving large number of river stretches from pollution and recycling treated sewage for reducing ever-increasing pressure on our water resources, sewage treatment and reuse remains a widely neglected field in our country.
- There is a wide gap between sewage generation and treatment capacity. This gap is widening because urban population is increasing at a fast rate and state governments continue their neglect towards this issue.
- There remains a gap between sewage generation and installed capacity.
- Plant faces problem of power failures and there is no standby arrangement.
- Plant was receiving low strength sewage that is effectively treated in primary units before feeding to subsequent activated sludge process.
- Overall shousekeaping at the STP was not satisfactory.
Sources of waste generation in India:
Wastes produced from different sources, are classified as follows:
- Municipal Solid Waste: The wastes, collected from the residential house, markets, streets and other places mostly in the urban areas and disposed of by municipal bodies are called municipal solid waste (MSW). The MSW are a mixture of paper, plastic, clothes, metals, glass, organic matter generated from households, commercial establishments and markets.
- Industrial Wastes: Industrial wastes are released from chemical plants, paint industrial, cement factories, power plants, metallurgical plants, mining operations, textile industries, food processing industries petroleum industries and thermal power plants.
- Non-hazardous wastes: These wastes are produced from food processing plants, cotton mills, paper mills, sugar mills and textile industries.
- Hazardous wastes: Hazardous wastes are generated by industries like metals, chemical, drugs, lather, pulp, electroplating, dye, waste that runs into stream from a factory can kill the aquatic fauna and also cause health problems for humans.
- Agricultural wastes: Agricultural areas produce plants and animals wastes. Excess use of fertilizer, pesticides and other chemicals used in agriculture and the wastes formed from these cause land and water pollution. They also contaminate the soil. Among pesticides chlorinated hydrocarbons, DDT, BHC, endrin, dieldrin etc are important which are absorbed by the soil and contaminate crops grown in the soil. Other agriculture wastes are produced from sugar factories, tobacco processing units, slaughter houses, livestock, poultry etc.
- Commercial Wastes: Huge amount of wastes are generated from various sources like markets roads, building, nursing homes and medical institutions. May chemical and disposal items are also generated from these sources.
- Mining: These wastes generated by mining activities the physical, chemical and biological features of the land and atmosphere. Radioactive wastes are also generated from mining activities.
- Bio-medical wastes: Wastes, which are produced from the hospitals, medical centres and nursing homes are called bio-medical wastes.
Consequences of waste generation:
Most of the wastes contain organic compounds a number of inorganic minerals and other harmful matter which contaminate the environment and lead to:
- Degradation of land,
- Pollution of drinking water,
- Destruction of aquatic life,
- Degradation of ground and surface water used for irrigation and industries, and
- Improper disposal of wastes cause soil, air and water pollution.
- Toxic gas carbon monoxide reduces the blood oxygen and formation of haemoglobin, causing injury to heart and central nervous system.
- Sulphur dioxide and sulphuric acid both cause irritation in the respiratory tracts of humans and high concentrations of sulphur dioxide leads to severe heart and lung diseases like bronchitis, asthma, etc.
- Nitrogen oxide at higher concentration affects respiratory organs, liver and kidneys.
- Ozone can seriously affect the pulmonary functions.
- Lead can cause injury in blood-formation organs and nervous system, especially impairing of brain functions of new-born babies
- Pesticides and radiations are other toxic air pollutants which are very dangerous for human health.
- Metal, dusts, asbestos and hydrocarbons shorten the life span and cause deterioration of nervous system and there is additional risk of cancer.
- In mining operation, silica and dust cause pneumoconiosis (common disease in mine workers) components can affect the blood forming organs, brain, teeth bones etc.
- Mercury and cadmium are known to damage the kidneys and brain.
- A large numbers of industrial pollutants that come to human body through drinking water and contaminated food threaten the life and health. The famous MINAMATA and ITAI-ITAI diseases took a big toll of human life in Japan due to mercury and cadmium from the industrial effluents in the aquatic ecosystem.
- Some agrochemicals like chlorinated pesticides disposed in water accumulate in the aquatic food chains and enter the human body causing heavy infection. In coastal Karnataka, several people died by consuming crabs contaminated with pesticides.
- Changes in water quality due to deficiency of iodine lead to Goitre which has been found to be endemic in many parts of India.
On Marine life:
- The growth of marine algae is affected.
- Massive oil spills not only spoil innumerable beaches and estuaries but also cause widespread damage to marine life.
- Herbicides and pesticides (especially the organ chlorides) reach the oceans via the wind and rivers and contaminate marine water.
- It is a matter of great concern that mangrove forests are being damaged at an alarming rate due to disposal of wastes along sea shores.
- Thermal and radioactive pollution have disturbed the life of fishes in estuaries and coastal ecosystems. Their breeding is also affected adversely.
Solid Waste Management Rules (SWM), 2016:
- The Union Ministry of Environment, Forest and Climate Change notified the new Solid Waste Management Rules (SWM), 2016.
Key features of the new rules are given below:
- Segregation at source: The new rules have mandated the source segregation of waste in order to channelize the waste to wealth by recovery, reuse and recycle.
- Collection and disposal of sanitary waste: The manufacturers shall provide a pouch or wrapper for disposal of each napkin or diapers along with the packet of their sanitary products.
- Collect Back scheme for packaging waste: As per the rules, brand owners who sale or market their products in packaging material which are non‐biodegradable, should put in place a system to collect back the packaging waste generated due to their production.
- User fees for collection: The new rules have given power to the local bodies across India to decide the user fees.
- Waste processing and treatment: As per the new rules, it has been advised that the bio-degradable waste should be processed, treated and disposed of through composting or bio-methanation within the premises as far as possible and the residual waste shall be given to the waste collectors or agency as directed by the local authority. The developers of Special Economic Zone, industrial estate, industrial park to earmark at least 5 per cent of the total area of the plot or minimum 5 plots/ sheds for recovery and recycling facility.
- Promotion of waste to energy: New rules emphasise promotion of waste to energy plants.
- Constitution of a Central Monitoring Committee to monitor the overall implementation of the rules.
- There is need for advanced technology.
- Bridging the ever widening gap between sewage generation and treatment capacity.
- Development of facilities to divert the treated sewage for use in irrigation to prevent nutrient pollution of water bodies, utilize the nutrient value of sewage in irrigation and bring down fresh water use in irrigation.
- Treatment of domestic sewage and subsequent utilization of treated sewage for irrigation can prevent pollution of water bodies, reduce the demand for fresh water in irrigation sector and result in huge savings in terms of nutritional value of sewage in irrigation.
- It is primary responsibility of state governments to establish sewage treatment and disposal facilities.
- State Governments should realize the problem of pollution of water bodies and pay attention to their liability to set up sewage treatment plants in cities and towns to prevent this pollution.
- Operation and maintenance of existing plants and sewage pumping stations is also a very neglected field which need to be addressed.
- Utilization of conventionally treated sewage for irrigation of crops not eaten raw is also equally important because of the following reasons:
- to save fresh water considering our diminishing water resources,
- to prevent nutrient pollution of our water bodies and
- to utilize nutrient value of sewage in irrigation. Importance of utilization of treated sewage in irrigation was emphasized in Water (Prevention and Control of Pollution) Act 1974,e. more than thirty years back but this issue continues to be largely neglected by State Governments.
Pollution in India:
Pollution in the context of India: a report:
- With 2.51 million deaths in 2015, India has been ranked No. 1 in pollution related deaths, according to a report by The Lancet Commission on pollution and health.
- India accounted for about 28 per cent of an estimated nine million pollution linked deaths worldwide in 2015.
- In the case of air pollution, the number of deaths in India from ambient air pollution is at the first place i.e. 1.09 million.
The Lancet Commission on pollution and health:
- The Lancet Commission on Pollution and Health is a two-year project that has involved more than 40 international health and environmental authors.
- The Lancet Commission on pollution and health addresses the health and economic costs of air, water, and soil pollution.
- Through analyses of existing and emerging data, the Commission reveals pollution’s severe and underreported contribution to the Global Burden of Disease.
- It uncovers the economic costs of pollution to low-income and middle-income countries.
- The Commission informs key decision makers around the world about the burden that pollution places on health and economic development, and about available cost-effective pollution control solutions and strategies.
Recent steps taken by the government to reduce pollution in India:
- The National Green Tribunal has been established on 18.10.2010 under the National Green Tribunal Act 2010 for effective and expeditious disposal of cases relating to environmental protection and conservation of forests and other natural resources including enforcement of any legal right relating to environment and giving relief and compensation for damages to persons and property and for matters connected therewith or incidental thereto.
- Namami Gange Project: Under the project, the Government is planning to make the areas around the river Open Defecation Free and to achieve Zero Liquid Discharge into the river.
- Smart Cities Mission and AMRUT project: Under these, the Government is planning to achieve 100 per cent sewage collection and its treatment before being discharged in river.
- Promotion of renewable energy, enforcement of Renewable Purchase Obligations and Renewable Generation Obligations to increase the share of renewable energy in total generation capacity.
- The Government has decided to enforce Bharat Stage VI norms from 2020.
- Furthermore, the Ministry of Roadways has undertaken the project to plant trees along the all major highways.
Laws related to air pollution in India:
- The Government of India under Article 253 of the Constitution of India enacted the Air Act, 1981 (“Air Act”) for the prevention, control and abatement of air pollution and further to implement the provisions of the Air Act
- The Air Act consists of fifty four (54) Sections divided into seven (7) chapters.
- Air pollution, according to the Air Act means the presence of any “air pollutant” in the atmosphere.
- The Air Act confers the regulatory power to the Central Pollution Control Board (“CPCB”) and the State Pollution Control Board (“SPCB”) to prevent and control the air pollution.
Central Pollution Control Board (CPCB):
- The CPCB of India is a statutory organization under the Ministry of Environment, Forest and Climate Change (MoEF&CC).
- It was established in 1974 under the Water (Prevention and Control of Pollution) Act, 1974.
- It also entrusted with the power and functions under the Air (Prevention and Control of Pollution) Act, 1981.
- It serves as a field of formation and also provide technical services to the Ministry of Environment and Forests under the provisions of the Environment (Protection ) Act , 1986
- It Co-ordinates the activities of the State Pollution Control Boards by providing technical assistance and guidance and also resolves disputes among them.
- It is the apex organization in India in the field of pollution control.
Functions and Power of CPCB:
- Advice the Central Government on improvement of air quality and prevention, control or abatement of air pollution and to provide training to persons engaged in such programs.
- Execute nation-wide programs for prevention, control or abatement of air pollution and training to persons engaged in such programs
- Give direction to SPCBs, co-ordinate between SPCBs and provide any technical assistance, guidance and resolve the disputes among SPCBs
TREATMENT TECHNOLOGIES IN VARIOUS SEWAGE TREATMENT PLANTS:
Class I cities:
- In Class I cities, Activated sludge process (ASP) is the most commonly employed technology. Activated sludge process (ASP) technology is the most suitable one for large cities because it requires less space as compared to other two technologies.
- Class I cities refers to cities having more than hundred thousand population.
- Anaerobic Sludge Blanket (UASB) technology. These two technologies are mostly used as the main treatment unit of a scheme including other primary or tertiary treatment units.
- Series of Waste Stabilization Ponds (WSP) technology is also important.
Class II cities:
- In Class II towns, series of Waste Stabilization Ponds (WSP) technology is the most commonly employed technologies.
- Class II cities refers to cities having fifty to hundred thousand population.
- Anaerobic Sludge Blanket (UASB) technology: UASB technology is mostly used as the main treatment unit of a scheme including other primary and tertiary polishing units.
Considering the urgency of preventing pollution of our water bodies and preserving our precious water resources, sewage treatment and reutilization of treated sewage need to be accorded higher priority. State Governments should realize the problem of pollution of water bodies and pay attention to their liability to set up sewage treatment plants in cities and towns to prevent this pollution.