Solid & Hazardous Waste Management

• Study notes on solid waste management, toxic and hazardous wastes, toxicology, risk assessment, and relevant laws and regulations.

Solid Waste Management

• Solid waste includes trash, organic waste, recyclables, hazardous waste, and e-waste.
• Methods for managing solid waste include landfills, incineration, composting, recycling, and waste-to-energy (WTE) conversion.
• Modern landfills have liners and leachate collection systems.
• Incineration reduces waste volume and generates energy.
• Composting decomposes organic material into a soil additive.
• Recycling processes waste materials into new products.

Shrinking the Waste Stream

• To shrink the waste stream: Minimize waste production, find new uses for old items, recycle waste materials, and compost organic waste.

Toxic and Hazardous Wastes

• Hazardous waste characteristics include being toxic, mutagenic, corrosive, explosive, flammable, reactive, and soluble.
• Secure landfills ensure containment of hazardous waste.
• Deep-well injection involves pumping waste deep underground.
• Surface impoundments are temporary storage ponds for waste.
• Bioremediation uses microorganisms to break down contaminants.
• Landfills are secure, but may cause leachate contamination.
• Incineration reduces waste volume but releases pollutants.
• Bioremediation is environmentally friendly but slow.

Brownfields Development

• Brownfields are abandoned or underutilized industrial/commercial sites contaminated by hazardous substances.
• The purpose of brownfield development is to redevelop these lands, reduce urban sprawl, and restore usability.

Toxicology, Risk Assessment, and Risk Management

• Toxicology studies the harmful effects of chemicals.
• Risk assessment includes hazard identification, dose-response assessment, exposure assessment, and risk characterization.
• Regulations and policies minimize risks considering factors such as cost, safety, and feasibility in risk management.
• Acute toxicity refers to immediate effects from short-term exposure, while chronic toxicity refers to long-term effects from continuous exposure.

Movement of Toxins in the Environment

• Bioaccumulation is the build-up of chemicals in an organism over time.
• Biomagnification is the increase in concentration of toxic substances as they move up the food chain.
• Persistent chemicals do not break down easily, while biodegradable substances decompose naturally.

Chemical Interactions

• Synergism occurs when chemicals amplify each other's effects.
• Antagonism occurs when one chemical reduces the effect of another.

Laws and Regulations

• RCRA (Resource Conservation and Recovery Act) regulates hazardous waste management.
• TSCA (Toxic Substances Control Act) controls chemical safety from production to disposal ("Cradle-to-Grave" management).
• CERCLA (Comprehensive Environmental Response, Compensation, and Liability Act - Superfund) funds cleanup of hazardous waste sites.
• CERCLA Creates the NPL (National Priority List) of contaminated sites.

Summary:

Be able to identify and discuss components of solid waste (trash), and describe the different

methods of solid waste management (e.g. - landfills, incineration, etc.);

Be able to identify ways to shrink the waste stream (reduce, reuse, recycle, composting, etc.);

Understand the concept of toxic and hazardous wastes;

Be able to discuss the advantages and disadvantages of the different strategies to manage and

remove toxic wastes;

Understand the concept of “brownfields” development;

Be able to summarize the basic principles of toxicology, risk assessment, and risk management;

Understand and discuss the movement, distribution, and fate of natural toxins and toxic

substances in the environment;