😷Environmental and Occupational Health Unit 7 – Solid & Hazardous Waste Management

Key Concepts and Definitions

• Solid waste encompasses discarded materials from residential, commercial, and industrial sources
• Hazardous waste contains properties that make it dangerous or potentially harmful to human health or the environment
  • Includes ignitability, corrosivity, reactivity, and toxicity
• Municipal solid waste (MSW) consists of everyday items discarded by the public
• Industrial waste originates from manufacturing processes and may include hazardous components
• Biomedical waste is generated from healthcare facilities and may contain infectious materials
• E-waste comprises discarded electronic devices and components
• Waste characterization involves identifying the composition and properties of waste streams
• Waste management hierarchy prioritizes waste reduction, reuse, recycling, and proper disposal

Types of Waste and Their Sources

• Municipal solid waste (MSW) originates from households, institutions, and commercial establishments
  • Includes food waste, paper, plastic, glass, and yard trimmings
• Industrial waste is generated by manufacturing, processing, and production activities
  • Varies depending on the specific industry (chemical, metallurgical, textile)
• Construction and demolition (C&D) waste arises from building, renovation, and demolition projects
  • Consists of concrete, wood, metal, and other building materials
• Agricultural waste is produced by farming and livestock operations
  • Includes crop residues, animal manure, and pesticide containers
• Hazardous waste exhibits characteristics that pose risks to human health and the environment
  • Generated by industries, hospitals, and households (batteries, chemicals, pharmaceuticals)
• Biomedical waste is generated by healthcare facilities, laboratories, and research centers
  • Includes infectious materials, sharps, and pathological waste
• E-waste comprises discarded electronic devices and components
  • Computers, mobile phones, televisions, and other consumer electronics
• Radioactive waste is generated from nuclear power plants, medical facilities, and research institutions

Waste Characterization and Classification

• Waste characterization involves identifying the composition, properties, and potential hazards of waste streams
• Physical characterization assesses the physical properties of waste
  • Includes density, moisture content, particle size, and calorific value
• Chemical characterization determines the chemical composition and potential reactivity of waste
  • Involves testing for pH, heavy metals, organic compounds, and other constituents
• Biological characterization evaluates the presence of pathogens and biodegradability of waste
• Waste classification categorizes waste based on its origin, properties, and potential risks
  • Helps determine appropriate management and disposal methods
• Hazardous waste is classified based on its ignitability, corrosivity, reactivity, and toxicity
• Non-hazardous waste is further classified as municipal, industrial, or special waste
• Proper waste characterization and classification ensures safe handling, treatment, and disposal

Environmental and Health Impacts

• Improper waste management can lead to environmental pollution and public health risks
• Landfills can contaminate soil and groundwater through leachate generation
  • Leachate contains dissolved and suspended pollutants from waste decomposition
• Open dumping and burning of waste release harmful emissions into the air
  • Contributes to air pollution, respiratory issues, and climate change
• Mismanaged hazardous waste can contaminate water bodies and ecosystems
  • Poses risks to aquatic life and human health through bioaccumulation
• Plastic waste accumulation in oceans and waterways harms marine life
  • Leads to entanglement, ingestion, and ecosystem disruption
• Improper disposal of e-waste exposes workers and communities to toxic substances
  • Heavy metals and persistent organic pollutants can cause health problems
• Waste-related activities can attract disease vectors like rodents and insects
• Occupational health risks for waste workers include exposure to hazardous materials and injuries
• Proper waste management is crucial for protecting the environment and public health

Regulatory Framework and Policies

• Waste management is governed by a framework of laws, regulations, and policies
• The Resource Conservation and Recovery Act (RCRA) regulates hazardous and non-hazardous waste in the United States
  • Establishes cradle-to-grave management system for hazardous waste
• The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) addresses the cleanup of hazardous waste sites
• The Basel Convention regulates the transboundary movement of hazardous waste
• The Stockholm Convention aims to eliminate or restrict persistent organic pollutants (POPs)
• The Waste Electrical and Electronic Equipment (WEEE) Directive promotes the recycling and safe disposal of e-waste in the European Union
• Extended Producer Responsibility (EPR) policies hold manufacturers responsible for the end-of-life management of their products
• Landfill regulations set standards for the design, operation, and closure of landfills
• Waste reduction and recycling targets are established to minimize waste generation and promote resource recovery
• Compliance with regulations and adherence to best practices are essential for effective waste management

Waste Management Hierarchy

• The waste management hierarchy prioritizes strategies for managing waste sustainably
• Waste prevention and reduction are at the top of the hierarchy
  • Aims to minimize waste generation through product design and consumer behavior changes
• Reuse involves using products multiple times before disposal
  • Promotes the repair, refurbishment, and donation of items
• Recycling converts waste materials into new products
  • Conserves natural resources and reduces the need for virgin materials
• Composting is the biological decomposition of organic waste into a nutrient-rich soil amendment
• Energy recovery extracts energy from waste through incineration or other thermal processes
  • Generates electricity or heat while reducing waste volume
• Treatment aims to reduce the hazardous properties of waste before disposal
  • Includes physical, chemical, and biological methods
• Landfilling is the least preferred option and involves the controlled disposal of waste in engineered facilities
• The waste management hierarchy guides decision-making and promotes sustainable practices

Collection, Transportation, and Storage

• Waste collection involves the gathering and removal of waste from generation points
• Collection systems can be door-to-door, community bins, or drop-off centers
  • Frequency and method depend on waste type and local infrastructure
• Waste transportation moves collected waste to treatment, recycling, or disposal facilities
• Proper containment and labeling are crucial during transportation to prevent spills and accidents
• Waste storage is the temporary holding of waste before further processing or disposal
• Storage facilities must be designed to prevent leaks, spills, and unauthorized access
  • Includes proper ventilation, secondary containment, and fire protection measures
• Hazardous waste storage requires special precautions and compliance with regulations
  • Includes segregation, labeling, and monitoring of storage conditions
• Waste tracking and manifest systems ensure accountability and proper management during transportation and storage
• Regular inspections and maintenance of collection, transportation, and storage infrastructure are essential

Treatment and Disposal Methods

• Waste treatment aims to reduce the volume, toxicity, or hazardous properties of waste
• Physical treatment methods include size reduction, separation, and dewatering
  • Shredding, screening, and filtration are common techniques
• Chemical treatment involves the use of chemical reactions to neutralize or stabilize waste
  • Includes precipitation, oxidation, and reduction processes
• Biological treatment utilizes microorganisms to degrade organic waste
  • Composting and anaerobic digestion are examples of biological treatment
• Thermal treatment applies heat to destroy or detoxify waste
  • Incineration, pyrolysis, and gasification are thermal treatment methods
• Landfilling is the controlled disposal of waste in engineered facilities
  • Modern landfills have liners, leachate collection systems, and gas management
• Secure landfills are designed for the disposal of hazardous waste
  • Require additional safety measures and long-term monitoring
• Proper treatment and disposal methods are selected based on waste characteristics and regulatory requirements
• Monitoring and environmental controls are essential to minimize impacts on surrounding areas

Recycling and Resource Recovery

• Recycling involves the collection, processing, and remanufacturing of waste materials into new products
• Reduces the demand for virgin raw materials and conserves natural resources
• Common recyclable materials include paper, glass, plastic, metal, and electronics
• Recycling programs can be source-separated or commingled
  • Source-separated recycling requires individuals to separate materials at the point of generation
• Material recovery facilities (MRFs) sort and process recyclable materials
• Recycling markets and demand for recycled products influence the economic viability of recycling programs
• Resource recovery extends beyond traditional recycling to include the extraction of value from waste
• Energy recovery through waste-to-energy processes generates electricity or heat from waste combustion
• Anaerobic digestion of organic waste produces biogas, a renewable energy source
• Nutrient recovery from wastewater and organic waste yields fertilizers and soil amendments
• Recycling and resource recovery contribute to a circular economy and reduce waste disposal

Emerging Technologies and Innovations

• Emerging technologies and innovations aim to improve waste management efficiency and sustainability
• Smart waste management systems utilize sensors, data analytics, and automation
  • Optimizes collection routes, monitors bin levels, and enables real-time decision-making
• Advanced sorting technologies, such as optical sorting and robotics, enhance recycling efficiency
• Plasma gasification converts waste into syngas, a versatile energy source
• Pyrolysis thermally decomposes waste in the absence of oxygen, producing oil, gas, and char
• Bioremediation uses microorganisms to break down and detoxify contaminated soil and water
• Landfill mining recovers valuable materials and resources from old landfill sites
• Waste-to-fuel technologies convert waste plastics and biomass into transportation fuels
• Biodegradable and compostable materials are being developed as alternatives to conventional plastics
• Blockchain technology enables transparent and secure waste tracking and transactions
• Innovative business models, such as product-as-a-service and sharing platforms, promote waste reduction

Occupational Health and Safety in Waste Management

• Waste management workers face various occupational health and safety risks
• Exposure to hazardous substances, such as chemicals, pathogens, and dust, is a major concern
  • Proper personal protective equipment (PPE) and training are essential
• Musculoskeletal disorders can result from manual handling and repetitive motions
  • Ergonomic interventions and mechanical aids can reduce risks
• Slips, trips, and falls are common hazards in waste management facilities
  • Maintaining clean and organized work areas is crucial for prevention
• Machinery and equipment pose risks of entanglement, crushing, and amputation
  • Proper guarding, lockout/tagout procedures, and operator training are essential
• Biological hazards, such as needle sticks and infectious diseases, are a concern for healthcare waste handlers
• Noise exposure from waste processing equipment can lead to hearing loss
  • Hearing protection and noise control measures are necessary
• Heat stress and dehydration are risks for workers in hot environments
  • Adequate hydration, rest breaks, and cooling measures are important
• Comprehensive health and safety programs, including training, hazard identification, and incident reporting, are crucial for protecting waste workers

Case Studies and Real-World Applications

• Curitiba, Brazil, implemented an innovative waste management system that rewards residents for proper waste separation
  • Resulted in high recycling rates and improved living conditions in low-income areas
• San Francisco, California, has achieved an 80% waste diversion rate through comprehensive recycling and composting programs
  • Mandatory recycling and composting ordinances have been instrumental in reaching this goal
• Dhaka, Bangladesh, faces challenges with informal waste picking and open dumping
  • Initiatives to formalize the informal sector and improve working conditions are being implemented
• The Ocean Cleanup project aims to remove plastic waste from the Great Pacific Garbage Patch
  • Utilizes large floating barriers to collect and concentrate plastic debris for removal
• The Closed Loop Fund provides financing for recycling infrastructure and sustainable manufacturing in the United States
  • Supports projects that enhance recycling capabilities and create markets for recycled materials
• The Eco-Park in Hiriya, Israel, transformed a former landfill into a recreational and educational facility
  • Demonstrates the potential for landfill rehabilitation and community engagement
• The Plastic Bank incentivizes the collection of plastic waste in developing countries
  • Provides income opportunities for collectors and reduces plastic pollution in oceans and waterways
• These case studies highlight the diverse approaches and successes in waste management around the world