ENVS 510 Solid Waste Exam 1

first exam for solid waste

Solid Waste Disposal Act (SWDA) 1965

Established programs to address US solid waste problems ie: research, investigations, training etc.

Resource Conservation and Recovery Act (RCRA) 1976

Set national goals to protect human health and the environment, set criteria for Municipal solid waste landfills, banned open dumping of solid waste and encouraged states to create a plan to manage waste. Subtitle D-Put states in charge of non-hazardous waste

Hazardous and Solid Waste Amendments (HSWA) 1984

Focused on waste minimization, phased out untreated hazardous waste at landfills and increased hazardous waste mgmt standards.

AB2439 (1976)

Issued permits for solid waste facilities

AB939 (1989)

Established California Integrated Waste Management Act resulting in the prioritization of source reduction, recycling and composting, and safe transportation and disposal, define law enforcement agencies, 25% waste diversion goal by 1995 (did not come close), 50% waste diversion by 2000

AB 341 (2011)

Increased goals for waste diversion by 75 percent by the year 2020

Types of Municipal Solid Waste

Residential, commercial and institutional locations

What happens to E-Waste?

mostly exported to foreign countries (from the US)

Policies and Strategies associated with E-Waste

1. International Basel convention -Bans Transfer of Hazardous Waste

2. EU-Cradle to Grave

Integrated Solid Waste Management Hierarchy

(From Most preferred to Least) Source Reduction & Reuse -> recycling & composing -> energy recovery -> Treatment and disposal (landfill)

Direct Benefits of Recycling

reduces solid waste disposal, reduces mineral demand, reduces energy demand, reduces water pollution, creates 5x more jobs than landfill, high success in recycling lead-acid batteries

Indirect Benefits of Recycling

protect species, reduces global warming, saves energy, makes fuel last longer

Barriers of Recycling

Working conditions, labor intensive, quality of materials(very specific conditions) , convenience (it is cheaper to make new)

Process of Recycling

Collecting materials, preparing materials, remanufacturing with recycled material

Biological Decomposition of Compost

1. Bacteria, fungi and insects: Produce CO2, heat, digested organic matter, and water (biological distribution)

2. Pathogen reduction: Density of fecal coliform less than 1000 MPN, density of Salmonella less than 3 MPN due to heat of 131F/3 days

Different forms of composting

1. Enclosed or within vessel

2. Windrow: aerobic conditions must be 131f or higher for 15 days or longer with a minimum of 5 turnings

Chemical Composition of Compost

Nitrogen (N), Phosphorous (P), and Potassium (K) monitored

*Heavy metal content must not exceed the maximum acceptable concentrations

Physical Requirements for Compost

Watert (not soggy), oxygen from turning, ph 6-8

optimal temp 131F greater than 131F fire risk, lower than 131F risk the growth of pathogens, ideally all particles are the same size

What is the role of a Materials Recovery Facility (MRF)

1. sort and recover recyclable materials

2. Concerns: vector control (falcon program), litter, air emissions of particulate matter from misters, noise, odor, traffic

What is the role of a transfer station?

1.  consolidate/compacted waste for transportation

2. Reduces truck traffic/air pollution/allows for waste screening

Benefits of incineration

1. waste to energy: generate electricity to run the facility and can sell to electricity companies

2. most of the toxic contaminants such as dioxin, fine particles, and highly toxic fly ash can be safely captured

3. incineration of toxic toxic medical waste and sewage sludge produces sterile ash

4. volume of combusted material is reduces by about 90% and 70%

Sanitary Landfill

prevents water contamination/air pollution

Leachate Collection Pipe

Collects and removes leachate to prevent groundwater contamination.

Compacted Clay

Low-permeability barrier that helps prevent leachate from reaching groundwater

plastic liner

Prevents leachate from escaping into the soil and groundwater

liner seams

Join and seal sections of the plastic liner together

textile mat

Protects and separates the liner and drainage system

washed rock

Allows leachate to drain toward the collection system

granular drainage layer

Carries leachate toward the collection pipes

cell creation

Waste is placed and compacted into individual cells

soil layer

Covers waste and helps control odors, litter, and vectors

Gas Collection pipe

Collect and monitor gases produced by decomposing waste

Leachate

a contaminated liquid that forms when rainwater or moisture filters through waste in a landfill, dissolving harmful chemicals and pollutants

holding ponds

Holds collected leachate before treatment or management

Landfill gas generation phase 1

1. aerobic bacteria (only live in oxygen) consume oxygen while breaking down organic waste

2. the primary byproduct of this phase is carbon dioxide

3. continues until all available oxygen is depleted can be days or months depending on how much oxygen was present when waste was desposed

Landfill gas generation phase 2

1. begins once oxygen is completely depleted and anaerobic decomposition processes dominate converting compounds into acids,

2. nitrogen and phosphorus become available

3. Ph drops

4. primary byproducts are carbon dioxide and hydrogen

Landfill gas generation phase 3

1. acids are consumed forming acetate creating a more neutral environment in which methane producing bacteria establish themselves

2. pH increases

3. methanogenic bacteria have mutually beneficial relationship with the acid bacteria

4. Methanogenic bacteria consume the carbon dioxide and acetate

carbon dioxide decreases slightly → methane increases→ nitrogen (other gases) decrease

Landfill gas generation phase 4

1. Begins when landfill gas composition and production stabilize (remain constant): CH4, CO2, N2 slow release

2. 45-60% methane, 40-60% carbon dioxide, 2-9% other gas

3. Continues at a stable rate for about 20 years

4. Different waste ages → different phases at the same time 

5. Summary: Landfill gas production becomes steady → methane and CO₂ are produced at relatively stable levels → continues for 20+ years

Gas will continue to be emitted for about 50 years or more after the waste is placed in the landfill

Fate of Carbon: Aerobic

1. CO₂ + MORE sludge due to ^ organisms, 4-60 days

   1. Heat loss, 100 to 10/12 kg COD

Fate of Carbon: Anaerobic

1.  CH₄ + LESS sludge after 60 days

   1. Biogas increase, 100 to 10/20 kg COD

Hydrolysis

1. fermentative bacteria produce enzymes that convert complex material to soluble compounds

   1. Proteins/carbs to amino acids/sugars, lips to fatty acids & alcohols

Acidogenesis

 H2 producing acidogenic bacteria that convert dissolved compounds to volatile fatty acids + CO₂ + H₂

Acetogenisis

acids to acetate + H₂ + CO₂, CO2 reducing methanogens

Methanogenesis

Acetate and methanol → CH₄ + CO₂, Aceticlastic methanogens

Environmental Landfill concerns

methane, leachate (garbage juice), habitat impact threat, high BOD

Geotechnical Landfill Criteria

soil, drainage, groundwater, precipitation

social landfill criteria

public health/safety, nearby residents, land use

Other landfill Criteria

climate, water wells (200 ft), transportation

Excluded Sites from Landfill placement

floodplains, aquifers, faults, wetlands, historic sites, endangered species, cannot be within 10,000 of an airport

Economic Landfill Criteria

property value, construction, operation/maintenance costs, away from property lines/residences

What is Biological Chemical Demand (BOD)?

represents the amount of oxygen consumed by bacteria and other microorganisms while they decompose organic matter under aerobic (oxygen is present) conditions at a specified temperature

What is Solid Waste?

trash, municipal, waste solids (sludge), e-waste, large scale discarded material

What is not allowed in landfills?

medical waste (unless treated), body fluids, body parts

How much does the US waste every year?

11 billion metric tons/year

Who are the largest producers of waste?

mining, oil, and gas

What is the fastest growing solid waste in North America?

E-waste

Source Reduction

Decrease packing, decrease toxicity, design products to last longer, purchase selectively

Recycling

“resource recovery method involving collection and treatment of waste product for use as raw material in the manufacture of the same or another product”

What is composting?

controlled biological decomposition of organic solid waste under aerobic conditions (decreases volume of waste by 75% when decomposed)

What does the U.S. EPA regulate for solid waste?

solid waste, transfer stations, and landfill operations on Title 40 CFR

What is CalRecycle responsible for?

Developing regulations and overseeing/enforcing regulations for solid waste facilities and Local Enforcement Agencies under Titles 14 and 27 CCR.

What are Local Enforcement Agencies (LEAs) responsible for?

Local enforcement of Titles 14 and 27 CCR.

What does the South Coast Air Quality Management District (AQMD) regulate?

Air quality regulations

What to consider when choosing a landfill location

Floodplains, endangered and threatened species, surface water quality, groundwater quality, food-chain crops, air quality, and health and safety