Chapter 16: Solid Waste Generation and Disposal

Waste as a System

Inputs include materials that are natural and manmade, used to produce goods - outputs are called waste, which is not useful or not consumed - energy waste is also an output - humans are the only organism that produces waste others cannot use

Planned Obsolescence

The process of designing a product so it will need to be replaced within a few years - typical of products in the US

Municipal Solid Waste (MSW)

Refuse collected by municipalities from households, small businesses, schools, hospitals, and town buildings - developing countries have become responsible for a growing portion of the global MSW due to growing populations and the production of various goods - paper products, organic materials, wood, plastic, E-waste, etc.

Types of Waste

• Municipal Solid Waste

• Agricultural Waste

• Mining Waste

• Industrial Waste

Goods vs. Waste

Goods are generally made of fibers, metals, and plastics - waste is from the manufacturing process, packaging, and transport

Waste Stream

The flow of solid waste that is recycled, incinerated, placed in a landfill, or disposed another way

Reduce

AKA waste minimization and waste prevention - limit your use - source reduction

Source Reduction

Seeks to cut waste by reducing the use of potential waste materials in the early stages of design and manufacturing

Reuse

Using a product/material that was intended to be discarded

Recycle

Materials are collected and converted to raw materials to produce new objects - closed loop and open loop

Closed-Loop Recycling

Recycling a product into the same product - cans, glass, plastic (bottles), metal

Open-Loop Recycling

Recycling one product into a different product - textiles make insulation, plastic makes stuffing, tires make asphalt

Composting

Creation of organic matter by decomposition under controlled conditions to produce organic-rich material - outdoor compost systems - large-scale composting facilities

Sanitary Landfills

Engineered ground facilities designed to hold MSW with little contamination of the environment - clay or plastic lining on the bottom - a system of pipes collects the leachate which is collected and tested regularly - covered with soil or clay (cap) when the landfill has reached capacity - should be located in loam or clay loam soil (low permeability is desirable so leachate doesn’t reach groundwater) - located away from water sources and population centers

Leachate

Liquid waste from landfills that is collected by pipes and tested regularly - can contaminate waterways and release methane and CO2

Incineration

Paper, plastic, food, and yard waste - can reduce the volume of solid waste by 90% - burning can release metals, other toxins, and lots of heat energy - some of that heat energy can be used in a process known as a waste to energy system - charges expensive tipping fees - need large quantities of municipal solid waste to burn efficiently and be profitable (so some communities do not promote recycling)

Ash

The residual nonorganic material that does not burn - ash is tested for a concentration of metals - bottom ash or fly ash

Bottom Ash

Residue collected at the bottom of the combustion chamber

Fly Ash

Collected from the chimney or exhaust pipe of a furnace

Hazardous Waste and its Four Characteristics

Liquid, solid gas, or sludge waste material that is harmful to humans, ecosystems, or materials

1. Ignitability

2. Corrosivity

3. Reactivity

4. Toxicity

Hazardous Waste Legislation

• US Resource Conservation and Recovery Act (RCRA)

• Comprehensive Environmental Response Compensation Liability Act (CERCLA)

  • Includes the Superfund Act

• Hazardous Waste and Solid Waste Amendments (HSWA)

Superfund Act

Imposes a tax on the chemical and petroleum industries, funds the cleanup of abandoned and non-operating hazardous waste sites, and authorizes the federal government to respond directly to the release (or threatened release) of substances that may pose a threat to human health or the environment

Brownfields

Contaminated industrial or commercial sites that may require environmental cleanup before they can be redeveloped or expanded