final Flashcards
Garbage
wet discards
Trash
dry discards
Refuge
Garbage + Trash
Rubbish
Refuse + Construction and Demo debris
“Fringe Effect”
anicent settlments, inhabitants pushed refuse to edges and corners
Pre WWII diposal
open burning dumps- spread waste over large area, pigs and scavengers.
Post WWII Disposal
open burning dumps became known as a public health hazard, sanitary landfills needed
1965 Solid Waste Disposal Act
made solid waste a big buisness, sold waste managment became a seperate entity from state vector control
Quantifying waste: Indirect Approach
use mathematical models based on materials flow- data from industrial production and consumption records (excludes garbage and rubbish)
Quantifying waste: Direct Approach
weights and volumes of refuse in landfill- archeological garbologists
amount of waste per person per day
about 4.1 lbs
most wasted food category
produce
In times of scarcity,
more food wasted. (people buy more, to stock up but then it goes bad)
package taxes
used to cover the cost of landfill (The ratio of product to packaging is higher for lower income families).
Diaper Dilemma, factors to consider
volume, and what is in the diapers
amount of energy for manufacturing or washing
water consumed for washing
threat to ground and surface water from contamination
air pollution produced by cleaning cloth
public health risk due to exposure to feces
cost of disposable diaper use
Major landfill contributors
paper, food, plastic, glass, metal, electronics batteris
factors to consider when determinging siting of a landfill
rock and soil beneath0 hydraulic conductivity, contamination of soil and groundwater
Lining of Landfill
several feet of dense clay, plastic liners, several feet of gravel or sand. Pack landfill with layers of soil
leachate
liquid that seeps to the bottom. Collected and treated at water sanitation places
Retiring a landfill
cover with thick layers of clay, pipes embedded to collect methane and decomposing bacteria,. turned into parks, gold courses. can only tell because of the methane well heads.
1876 Resrouce Conservation and Recovery Act
directed EPA to develop criteria for open landfills and sanitary landfills
hazardous waste
a solid or combination of solid waste, which because of its quanitity or concentration or physical, chemical or infectious characteristic may cause or significantly contribute to an illness or pose a substantial present or potential hazard to human health or environment. Can be ignitable, corrosive or reactive
most toxic waste enters from
non-point source
residential hazardous waste
1 % of household waste, chemicals, glues, pesticides, fertilizers, detergents and oven cleaners.
hazardous waste sites
built on bedrock, layers of impermeable clay and plastic, pipes at the bottom which collect leachate, plastic liners have sensors to alert in case of leak
health risk assessment near waste sites
relative risk (RR), standard mortality ratio (SRM), odds ratio (OR), or standard fertility ratio (SFR)
Bhopal, India 1984
water entered an underground storage tank constaining methyl isocyanate and caused a violent explosion, released MIC in aerosol into the air. 2,500 died in the first few hours. 5,000 dead and 200,000 sick or injured by the fourth day.
revolution in chemical plant safety and communication between chemical plants, public safety and communitu.
Responsible Care
guiding principle and managment practice codes that chemical companies should abide. a code for post accidents, and accident prevention and environmental stewardship
Toxic Substance Control Act 1976
requires testing, regulating, screening all chemicals produced of imported into the US. schools must inspect for asbestos, EPA study radon lecels, resource conservation and recovery, sold and hazardous waste “cradle to grave”
CERCLA Superfund Act 1980
“superfund” from tzes o nchemical feedstocks to clean up abandonded hazardous waste sites and accident spills. each contributor can be held responsible for the entire cost of clean up (joint and several liabilitites)
Emergency Planning and Community Right to Know Act 1986
release of toxic chemicals. requires industry and government to report toxic release, encourage planning by local communitities to respond to chemcical emergencies
Largest accident in the US, Texas City 1947
freighter exploded, with cotton, peanusts and ammonium nitrate
clean up methods for contaminated sites
extraction, biorememdiation, phytoremediation
sources of drinking water
rainfall, surface water, ground water, desalinized water, reclaimed water
reservoir
store natural water, selected as protected watersheds
ancient water treatment methods
bad or cloth to strain water remove solids. first in S in 1908 used chlorine as disinfectant to control waterborne dieases
water supplies in the 1800’s transmitted
cholera, dysentery, hepatitis and typhoid
storage of water
first step of treatment, almost all pathogenic bacteria are eliminated by stoaring water for 1-5 weeks. water is prechlorinated or treated with ozone to kill organisms
coagulation and flocculation
chemicals added to water to precipitate undesirable minerals, chemicals, microoganisms. usually ALUM. A floc forms and settles to the bottom of the tank.
Filtration
water flows through, sand and suspended materials trapped in top layers, form biofilters that screen out smaller particles
Water in Los Angeles
:A aquaduct, groundwater 12%, and MWD purchased 47%. most from high sierra mountain range
Disinfection
final step of purification. chorine, ozone, UV light. chlorine disinfects by exposing pathogens to free availible chlorine, ozone disinfects by generating hydroxl radicals- damages membranes of DNA pathogens
Transporting water to users
leaks, cross connection (break in water main becomes contaminate)
Transmission contaminants
deterioration of pipes and fitting. brita filters
Odor
chemicals that bind to proteins in the nose (Odorant binding protenins) bind to the brain receptors where signal and odor can be identified.
Drinking Water, Biological Contaminants
bacteria, protozoa, helminthes, viruses, fungi
Bacteria
Slomonella. Cholera, typhoid fever. rarely occur in the developed world
Protozoa
microscopic, single celled organisms. parasites, form cysts.
Cryptosporidia, major threat to domestic water supplies, contaminated by animal feces from agriculutal runoff. resistant to chlorine and and small enough to make it through many filters. difficult to identify.
Giardia Lambia- spread by forest animals, beavers, raccons, persistent diarrhea
amoebic dysentery0 in placed with poor sanitation and in hopsiticals, rare in the united states, causes cysts,
Helminthes
flat or round parasitic worms, in industrial nations. vectors spread them, (fish tapeworm).
viruses
at least 6 virus groups, with over 100 different strains are known to be releases. ?Hepatitis A, virus causes diesase. more difficult to identify. large proportion of the unidentified agents that result in outbreak of diease
Fungi
skin rase and eye disorders
Primary Water Quality Indicators
Radioactivity- decay or radium.
Toxic elements- metals, Arsenic (main, lots of contamination in bangladesh and west bengal india)
Arsenic Toxicity
liver, kidney, muscles, heart, spleen. methylized in body
nitrate
odorless, colorless, naturally present in vegetables. blue baby syndrome- well water becomes loaded with high concentration from fertilizer, manure and septic system.
Disinfection By- products
Trihalomethans (THM)- from treating water with chlorine. potential carcinogens, regulated in drinking water, remove by running through a charcoal filter
chloroform
used as an indicator. presense of other halogenated or oxidized chemicals.
The most probable number
to count bacteria. indirectly tests for the presence of pathogens in water based on the application of Poisson distribution for extreme numbers
Thomas equation:
Turbidity
one unity is equivalent to 1 mg og silicon dioxide per liter
nephelometric turbitiy unit
light scallered on standard solution
Secondary Water Quality Indicators
Aesthetic.
Color- can add potassium Odor Acidity Total Dissolved Solids-all waterborne inorganic chemicals Unregulated constituents water hardness total organic carbon
Safe Drinking Water Act 1974
water must appear clean, taste pure and meet standards for toxic chemicals
Bottled Water
not regulated by the EPA. the FDA regulated. 30% were contaminated with chemicals or bacteria at levels that would exceed EPA regulation. maybe becasue of large storage tanks. 40% of bottled water is tap water (does meet EPA standards). Bottled water uses about 2000 times as much energy as tap water.
Water use in US
81 % irrigation, only 7% for public supply.
methods of filtration
biofilter- mat composed of algae, or other biological material
charcoal, coal or other carbon- used to remove organic chemiccals
sand, gravel
Acid Rain
pH is less than 5.6, aquatic orgaisms very sentsitive, dissolved metals rock
Eutrophication
2/3 of lakes in the US have serious eutriphication problem
60-70% of community water
(water that is distributed to a community) is returned through sanitary sewer system
STORM SEWERS
deliver to nearby lakes, rivers. prevents flooding. some have grids to trap debris, but mostly flow untreeted.
waste water treatment
remove waste so when returned to the environment it does nto cause eutrophication.
primary waste water treatemtnt
mechanical reducation of Total Suspended Solids (bar screens)
Secondary waste water treatment
removal or organic matter from the water, by converting it to biomass. aeration tank- adding activated sludge containing bacteria, protozoa, metazoa and algae. sits for 4-8 hours. moved to secondary settling tank, for 1-2 hours. or use a trickling filter made of crushed stone and gravel
Tertiary waste water treatment
remove remainting solids. pass water through filter, sand. or use aeration tower to remove volitile ammonia, phosphorus and industrial chemicals.
then dieinfection, usually by chlorination
Sewage Farming
first introduced in 1840. sewage water applied directly to agriculrual land for irrigation and fertilization. replaced by aerobic treatment in 1919.
recently it has come back by using ornamental plants,
Indicators important for ecological health
heat- as temperature increases, growth of bacteria, algae and pathogens increases
Dissolved Oxygen Biological Oxygen Demand Chemical Oxygen Demand Total Suspended Solids Sediments- the major form of water pollution.
The Clean Water Act 1972
sewage treatment construction grants, regulatory and enforcment program for discharges od pollutants into US waters. dischargers must obtain permits
Threshold contrast
the point where an object becomes visible. influsenced by illumination, reflection, abosorption, scattering of light
Rayleigh scattering
scattering of light by air molecules, responsible for the increase in blue intensity in the ky distant from the sun. blue light scatters most becasue it has a low wavelength
Tyndall scattering
light scattering by small particles in the air column, related to their size and is strongest when their diameter is equivalent to wavelength. derived from fog, rain, snow, wind blown dust, natural haze
sunset
when air molecules scatter blue, the sunset looks reddish.
gray and brownigh sky
dust particles scatter blue light and some green. the absorption of blue and green by No2 results in grayish brown sky and reddish sun. makes deep red sunsets, and results in the red brown appearence of smog