Week 7: Solid and Hazardous Waste Flashcards
What is the history as solid/hazardous waste? What are the problems posed by urbanization?
History: waste of early humans highly organic, evolved to incl. refined material (paper, cloth) and inorganic
materials (ceramics, metals), to complex mix of industrialized society wastes late 19th/20th centuries
Urbanization: space shortage, open dumping/burning no longer acceptable, waste management challenges
Define waste. What are the 3 broad categories of waste in the U.S.?
Waste = material that no longer has value (influenced by cultural norms)
Broad categories:
1. Municipal solid waste
2. Special waste
3. Hazardous waste
What are the dangers of hazardous waste? List examples.
Hazardous, or toxic, waste threatens human health or the environment because it is poisonous, dangerously chemically reactive, corrosive, or
flammable
Examples include:
Industrial solvents.
Hospital medical waste.
Car batteries.
Household pesticide products.
Dry-cell batteries.
Ash from incinerators and coal-burning power plants
List 3 U.S. laws/regulations relating to waste and their key points.
Solid Waste Disposal Act of 1965: authority (limited) to U.S. Public Health Service to help states develop plans
Resource Conservation and Recovery Act (RCRA), 1976:
Gave EPA authority to regulate solid and hazardous waste
Required haz. waste tracking, generation to treatment/disposal
Construction standards (e.g., liners) for new solid waste landfills
Comprehensive Environmental Response Compensation
and Liability Act (CERCLA), 1980 (“Superfund”)
Response to shocking hazardous waste dump discoveries at Love Canal (NY), Times Beach (MO), Valley of the Drums (KY)
Key provisions: EPA/states must identify/prioritize sites (Hazard
Ranking System, National Priorities List); provide for cleanup; execute polluter pays, i.e., tax on chemical, petroleum industries to fund cleanup; incorporate community input
Define special waste. Give examples.
Special: not MSW, not hazardous; separate regulations
Medical waste: items w/potentially infectious agents; handled separately to protect sanitation workers, esp. from needles
Ebola-??
Construction debris: construction or demolition, drywall H2S risk
Asbestos: regulated separately
Mining waste: metals, coal, oil extraction; volume > all other categories; regulated by solid waste, water pollut., land use laws
Agricultural waste: animal wastes especially problematic
Radioactive waste: low-level, special landfills; high-level; no U.S.
facility yet, temporarily in spent fuel pools, dry cask storage
Sewage sludge: disposal depends on hazardous components
Electronic waste: growing problem, sent U.S. to Asia, Africa
Define hazardous waste.
Hazardous: in U.S., from ~500 specific industries or meets 1 of: ignitability, corrosiveness, reactivity, toxicity
What are 4 details about e-waste?
The EPA has estimated that in 2010, e-waste totaled 2.4 million tons, or about 1% of the municipal waste steam.
About 71% of that e-waste was discarded, primarily in landfills, and the rest was recycled (U.S. EPA, 2011).
Improper disposal of e-waste is of concern because electronic components contain hazardous metals, such as lead, cadmium, and mercury, and the plastic housings and cables contain brominated flame retardants, such as polybrominated biphenyls (PBBs)
Cathode ray tubes (CRTs), or picture tubes are of particular concern because they contain, on average, about 4 lbs of lead; if disposed in unlined landfill, lead could contaminate groundwater
What are the preferred methods of e-waste management in preference order?
- Reuse the equipment
- Recycle the materials
- Properly dispose of the equipment in an approved landfill
What are 2 details about e-waste recycling?
In the United States the high costs of labor and equipment and strict environmental regulations are obstacles to economically viable recycling of e-waste
Consequently, the United States and other industrialized nations ship large quantities of e-waste to Asia and more recently to Africa for recycling
What are 3 details about solid waste management strategies?
Multitier approach best, starting w/avoidance, reduction
Primary prevention (reduce, reuse, recycle):
Reduce (e.g., substitute less toxic materials in industrial processes, use reusable canvas shopping bags)
Recycle: using waste material to produce more of original product or use in something else (e.g., make new Pb batteries from old Pb batteries; use mining waste for concrete/asphalt)
Lifecycle analysis and industrial ecology help identify options
Disposal strategies in U.S. (EPA 2012): ~54% of MSW is landfilled
Hazardous waste: landfills/surface impoundments (15%), energy recovery units (13%), metals recovery operations (13%), deep well or underground injection (10%), other
List the first priorities (4), second priorities (5), and last priorities (4) for integrated waste management.
First priorities:
Change industrial processes to eliminate use of harmful chemicals
Use less of a harmful product
Reduce packaging and materials in products
Make products that last longer and are recyclable, reusable, or east to repair
Second priorities:
Reuse
Repair
Recycle
Compost
Bye reusable and recyclable products
Last priorities:
Treat waste to reduce toxicity
Incinerate waste
Bury waste in landfills
Release waste into environment for dispersal or dilution
Give 2 details about recycling. What are the 2 types?
Recycling involves reprocessing discarded solid materials into new,
useful products
Households and workplaces produce five major types of materials
that we can recycle: paper products, glass, aluminum, steel, and some
plastics
Primary, or closed-loop, recycling: materials are recycled into new
products of the same type
Secondary recycling: waste materials converted into different
products
What are 5 details about composting?
Involves using decomposer bacteria to recycle yard trimmings, food scraps, and other organic wastes
The resulting organic material can be added to soil to supply plant nutrients, slow soil erosion, retain water, and improve crop yields
Homeowners can compost such wastes in simple backyard containers
Some cities in Canada and in many European Union countries collect and
compost more than 85% of their biodegradable wastes in centralized community facilities
In the US, about 3,000 municipal composting programs recycle about 60% of the yard wastes
What 3 factors hinder reuse and recycling?
The market prices of almost all products do not include the harmful
environmental and health costs associated with producing, using, and
discarding them
The economic playing field is uneven, because in most countries,
resource-extracting industries receive more government tax breaks and
subsidies than reuse and recycling industries
The demand, and thus the price paid, for recycled materials fluctuates,
mostly because buying goods made with recycled materials is not a
priority for most governments, businesses, and individuals
What are 4 ways to encourage reuse and recycling?
Increase subsidies and tax breaks for reusing and recycling materials and decrease subsidies and tax breaks for making items from virgin resources
Increase use of the fee-per-bag waste collection system and encourage or require government purchases of recycled products to help increase demand for and lower prices of these products.
Pass laws requiring companies to take back and recycle/reuse packaging and electronic waste
Citizens can pressure governments to require product labeling that lists recycled content of products and the types and amounts of any hazardous materials
What are the 2 waste treatment and disposal methods for high-income countries? Give details for each. What methods are used for low- and middle-income countries?
High-income countries:
Sanitary landfill: location (adequate space, surface/ground-water protection, buffer), sediment/erosion controls, leachate barrier/treatment, methane control, daily earth covering, etc.
Haz. waste landfill: similar features, more strictly regulated
Incineration: controlled combustion (3 T’s: time, temperature, turbulence); some generate energy; strict air pollution controls
Stoichiometric air requirement: deep well injection: force liquid wastes (e.g., brines) into several 1000 ft. deep geological formations, away from aquifers
Other: composting, vitrification, thermal desorption, etc.
Low- and middle-income countries: open burning, dumping still common, contributing 29% of global particulate air pollution, 10% global Hg emissions, 5% of anthropogenic CO2 (Wiedinmyer et al. 2014)
What are 7 details about tires and waste?
Waste tires are problematic for both storage and disposal
They are hard to bury in landfills.
Landfill operators report that tires tend to work their way up to the surface of the fill and disrupt the integrity of the cover.
Tires also collect water and serve as mosquito-breeding sites when stored outdoors
And when stored in large piles, tires are
vulnerable to fire.
In the United States the number of stockpiled scrap tires has been reduced from a total of 1 billion in 1990 to 76 million in 2011(Rubber Manufacturers Association, 2014).
After being broken into chunks of rubber, used tires are being used in truck bed liners, antifatigue mats, soaker hoses, shoe soles, swings, and civil engineering material.
What are 4 ways to detoxify hazardous waste?
Bioremediation employs bacteria and enzymes that help destroy toxic or
hazardous substances or convert them to harmless compounds
Phytoremediation involves using natural or genetically engineered plants to absorb, filter, and remove contaminants from polluted soil and water
Hazardous wastes can be incinerated to break them down and convert them to harmless or less harmful chemicals such as carbon dioxide and water.
Detoxify hazardous wastes by using a plasma arc torch, somewhat similar to a welding torch, to incinerate them at very high temperatures
What are 3 details about storing forms of hazardous waste?
Burial on land or long-term storage of hazardous and toxic wastes should be used only as the last resort
Currently, burial on land is the most widely used method in the
United States and in most countries, largely because it is the least
expensive of all methods.
The most common form of burial is deep-well disposal: liquid hazardous wastes are pumped under pressure through a pipe into dry, porous rock
formations far beneath aquifers that are tapped for drinking and irrigation water
Give 5 examples of infectious medical waste.
Blood and blood products in a
free flowing, unabsorbed state
Contaminated sharps
Isolation Wastes
Laboratory wastes
Unfixed pathological tissues
What are 6 details about waste shipping and manifests?
Every load of waste shipped off-site for destruction is tracked using a
manifest system
The manifest is a multiple copy document that accompanies the
waste to the treatment facility
Every individual who takes possession of the waste, including someone from your facility, must sign the manifest
As the waste generator, your facility is responsible for the waste until
you receive the proof-of-destruction copy of the manifest
The proof-of-destruction copy of the manifest must be returned to your facility within 50 days from the date that the load of waste was picked up.
All proof-of-destruction manifests must be kept on file at your facility
for 3 years
How should waste be shipped?
Wastes shall be collected in a lined, cardboard box or reusable plastic container that is labeled with the biohazard symbol and appropriate wording
Once the box or container is full, the bag lining it must be sealed and the container then sealed shut
date
Boxes must be labeled with facility name, address, phone and fax numbers, and the date
A full, sealed container can be stored on site for no more than 30 days
Why is it important to segregate waste?
If non-hazardous waste (paper) is mixed in with hazardous waste (medial waste), the non-hazardous waste becomes contaminated
Everything then has to be treated as medical waste, which costs a lot to properly dispose of
What are 5 details about international trafficking in hazardous wastes?
The United Nations Environmental Programme estimates that about 10% of hazardous waste produced worldwide is shipped across international borders
Hazardous waste workers often lack adequate personal protective equipment and training, which puts their health and safety at risk
Furthermore, if the wastes are not adequately treated and disposed of, they can create a potentially dangerous environmental legacy for the recipient country
Concern over the international shipping of hazardous wastes led to the
establishment in 1989 of a treaty known as the Basel Convention.
One of the key provisions of the convention is that transboundary movement of hazardous wastes can take place only upon prior written notification by the state of export to competent authorities of the state of import
What are 4 additional details about international trafficking in hazardous wastes (ship breaking)?
One of the challenges facing the convention is how to deal with trafficking in recyclable materials, such as spent lead-acid batteries and other nonferrous scrap metal. These wastes are valuable commodities on the world market, and recycling these materials provides jobs and generates income in countries with struggling economies. Under a proposed amendment to the Basel Convention, the transfer of such materials from industrialized to developing countries would be banned
In recent years the practice of ship breaking has attracted the attention of the environmental community. Some environmental groups have characterized this practice as being a covert form of international trafficking in hazardous wastes
The term ship breaking refers to sending decommissioned ships to other countries where they are dismantled to recover steel and other recyclables.
Concerns have been raised because workers may not be protected from exposure to lead, asbestos, polychlorinated biphenyls, mercury, and other hazardous materials during ship dismantling operations. Nearly all of the world’s ship breaking occurs in five nations: India, Pakistan, Bangladesh, China, and Turkey
(Sarraf et al., 2010)
What are 5 health concerns relating to waste?
Infectious disease risks from poorly managed solid waste: pests
(mosquitoes, rats, mice, fleas, etc.),
Contamination of drinking water, soil by biological, chemical, mining
wastes: VOCs, metals, common in landfills, easily migrate from
unlined landfill to aquifer
Landfill gas migration, leachate discharges: CH4 (anaerobic
microbial degradation of organic matter), H2S, VOCs = explosion
risk; CH4 & CO2 = greenhouse gases
Air pollution (incinerators, smelters, open burning): metals, particulates, vapors, gases, chlorinated by-products including highly toxic dioxins and furans
Food contamination by waste chemicals escaping into environment
(e.g., dioxins bioaccumulate in food chain)
