Solid Wastes
Solid wastes refer to everything that goes out in trash.
Municipal solid wastes are wastes from homes, offices, stores, schools, hospitals, etc., that are collected and disposed of by the municipality.
Not all solid wastes can be completely burnt. Open dumps serve as breeding grounds for rats and flies.
Sanitary landfills are substitutes for open-burning dumps. In sanitary landfills, wastes are dumped in a depression or trench and covered with dirt.
Limitations of Landfills:
- The amount of garbage, especially in metropolitan areas, has increased so much that these sites are getting filled too.
- Seepage of chemicals from landfills pollutes underground water resources.
Solid wastes are categorized into three types:
- Biodegradable: These undergo natural breakdown.
- Non-biodegradable: Examples include plastic packets, polybags, polystyrene, etc.
- Recyclable: Examples include plastics, e-wastes, etc.
Eco-friendly packaging can be used instead of plastics, such as cloth or natural fibre carry-bags.
Hospital wastes contain disinfectants, harmful chemicals, and pathogenic microorganisms. They are incinerated.
Electronic Wastes (E-wastes)
All irreparable electronic goods are known as e-wastes. They are buried in landfills or incinerated.
Recycling is the only eco-friendly solution for treating e-wastes, but during recycling, workers are exposed to toxic substances present in e-wastes.
Over half of the e-wastes in the developed world are exported to developing countries (e.g., China, India, Pakistan), where metals such as copper, iron, silicon, nickel, and gold are recovered during the recycling process.
Polyblend: A Remedy for Plastic Waste
Ahmed Khan, a plastic sack manufacturer in Bangalore, developed Polyblend, a fine powder of recycled modified plastic.
Polyblend is mixed with bitumen and used to lay roads. This blend enhances bitumen’s water-repellent properties and increases road life.
Agro-chemicals and Their Effects
Inorganic fertilizers, pesticides, herbicides, fungicides, etc., are toxic to non-target organisms that are important components of the soil ecosystem. These are biomagnified in terrestrial ecosystems.
Chemical fertilizers cause eutrophication.
Integrated Organic Farming
Integrated organic farming is a cyclical, zero-waste procedure where waste products from one process are cycled in as nutrients for other processes, maximizing resource utilization and increasing production efficiency.
Ramesh Chandra Dagar, a farmer in Sonipat, Haryana, included bee-keeping, dairy management, water harvesting, composting, and agriculture in integrated organic farming. Its advantages include:
- They support each other and allow an economical and sustainable venture.
- No need for chemical fertilizers, as dung is used as manure.
- Crop waste is used to create compost (natural fertilizer) or to generate natural gas (provides energy for the farm).
Dagar has created the Haryana Kisan Welfare Club, with a membership of 5,000 farmers, to spread information on the practice of integrated organic farming.
Radioactive Wastes
The use of nuclear energy has two serious problems:
- Accidental leakage: Examples include the Three Mile Island and Chernobyl incidents.
- Safe disposal of radioactive wastes.
Nuclear radiation causes mutations and is lethal at high doses. At lower doses, it causes disorders such as cancer.
It is recommended to store nuclear wastes in shielded containers buried within rocks, about 500 meters deep below the earth’s surface. However, the public opposes this method.