ENVS200-wk15.2-waste2
Waste Management Overview
Lecture led by Cuesta College regarding waste management strategies.
Student Learning Objectives
By the end of this lecture, students will be able to:
Explain the importance of the 4 R’s of managing waste (Reduce, Reuse, Recycle, Recover).
List the pros and cons of recycling.
Discuss the pros and cons of burying waste versus burning waste.
Explain the components that make up a sanitary landfill.
Waste Management Recommendations
Comparison of recommended versus actual waste management practices:
What We Should Do:
Reduce waste generation (67%)
Reuse materials
Recycle/Compost (23.7%)
What We Actually Do:
Bury waste (67%)
Recycle/Compost (23.7%)
Incinerate (9%)
Individual Reuse Strategies
Discussion on how individuals can successfully reuse purchased items.
International Approaches to Packaging
Governmental efforts to limit single-use packaging:
Bans on non-reusable beverage containers.
Finland's high rate of refillable beverage containers (95%).
Taxation on single-use plastic shopping bags.
Hawaii's ban on plastic shopping bags in 2014.
Potential of Recycling
Life cycle of products across recycling processes:
Primary/Closed Loop Recycling: Existing aluminum cans recycled to become new cans.
Secondary Recycling: Waste materials transformed into different products.
Three Key Recycling Steps:
Material Collection.
Conversion to New Products.
New Commercial Sales.
Note: The effectiveness of recycling relies on consistency in all three steps.
Global Plastic Recycling Rates
Worldwide statistics on recycling plastics:
Approximately 60% of collected plastics are recycled.
Only 15% of plastics are initially collected for recycling;
Calculation: 60% of 15% results in 9% total recycling rate.
Composting Practices
Overview of composting:
Involves using bacteria to decompose organic waste (yard trimmings, food scraps).
Benefits of composting include:
Nutrient enrichment in soil.
Reducing erosion and improving water retention.
Enhancing crop yields.
Data reveals 33% of food is wasted in the US, with only 2.5% composted.
Pros and Cons of Recycling
Debate surrounding recycling:
Critics Argue:
Costs and taxes burden taxpayers.
Viable economically mainly for paper, cardboard, steel, and aluminum.
Proponents Affirm:
Benefits in economic, health, and environmental spheres outbalance costs.
Cities profit from recycling through:
Single-pickup systems.
Pay-as-you-throw approaches.
Creating 6-10x more jobs than landfills/incineration.
Case Study: San Francisco
2009 Initiative: Mandatory recycling and composting ordinance in SF:
Requires separation of recyclables, compostables, and trash.
By 2012, 78% of municipal solid waste (MSW) was recycled, composted, or reused.
Future goals updated in 2018 to:
Reduce waste generation by 15%.
Reduce landfill/incineration disposal by another 50%.
Commitment to Zero-waste goals.
Burning Solid Waste
Overview of modern technologies for waste incineration:
Techniques have improved, with large waste-to-energy incinerators:
Use heat to generate steam for electricity/heat buildings.
Environmental Concerns:
Contributes to air and water pollution.
Emits greenhouse gases.
Ash produced may contain toxic chemicals, requiring safe disposal.
Incineration Statistics
In the USA, approximately 9% of MSW is incinerated.
Comparison with Denmark, which incinerates 54% of its MSW.
Waste-to-energy facilities in Denmark exceed European air pollution standards.
Incinerating waste can undermine recycling efforts and increase landfill demand.
Burying Solid Waste
Two main types of landfills:
Sanitary landfills: controlled disposal of waste.
Open dumps: unregulated fields for waste deposition.
Characteristics of Sanitary Landfills
Components of sanitary landfills:
Solid wastes are layered, compacted, and covered regularly.
Benefits include:
Dry materials limit leaching.
Reduces odors and fire risks.
Discourages vermin access.
State-of-the-Art Sanitary Landfill Features
Design includes:
Strong double liners at bottoms and sides.
Systems to collect leachate.
Methane collection systems for energy use (burned as fuel).
Capable of handling large waste amounts with low operational costs.
Case Study: Boomers in Santa Maria
Example of land-use on a capped landfill, featuring:
Golf courses, parking lots, and playgrounds developed without excavation.
Characteristics of Open Dumps
Description of open dumps:
Large fields for garbage with minimal regulation.
Significant risks of leakage and methane release.
Landfill Locations in SLO
Key landfills in San Luis Obispo (SLO) County:
Chicago Grade Landfill (Templeton).
Paso Robles Landfill (Paso Robles, San Miguel).
Cold Canyon Landfill (SLO).
All considered sanitary landfills permitted by CalRecycle.
Recycling in SLO County
Recycling specifics:
Plastics categorized 1-7; only 1, 2, and 5 are recyclable.
1-2-5 plastics accepted for recycling.
Recycling Guidelines in SLO County
General recycling rules:
No plastic or trash bags accepted for recycling.
Containers must be rinsed before recycling (e.g., glass, cans).
Frozen food boxes and milk/juice jugs are non-recyclable.
Materials Recovery Facility (MRF)
Overview of recycling processes at MRF:
Multi-step sorting of recyclables by type.
Green Waste and Organics in SLO County
Overview of Kompogas SLO:
Anaerobic digester established in 2018 for processing organic waste.
Captures methane generated during decomposition for energy.
Produces high-quality soil sold to farmers.
Types of Organic Waste Processed
Types of materials processed through Kompogas:
General categories include:
Yard waste (grass, trees).
Food waste (meat, bones, fruits).
Exclusions: liquids and compostable plastics.
Future Plans for Composting
North SLO County composting initiatives:
Current open field composting with plans to add anaerobic digesters.
Senate Bill (SB) 1383 signed into law aims to reduce organic food waste by 75% by 2025.
Paso Robles implements a 3-container system to avoid penalties.