quiz 11.9.19
- based only on sifting percentages, which sample would have the highest and lowest percolation time?
- Which did have the highest and lowest percolation time?
- Why might a sample have a water retention not based solely on sifting percentages?
- Why are some of the soils acidic, and why is this an evolutionary advantage?
Water Pollution-Ch. 14 F/R
Big ideas:
1. Rivers are continuous, so easier to find sources along the route (continuity analysis: all sources add to total)
2. Groundwater is harder to determine point sources, as flow is over larger area (not confined by river banks) and there is no continuity analysis possible (we don't know sources and sinks)
3. Oceans are the hardest to trace, and impact everyone eventually
Surface water impairment:
Module 41-Humans and livestock
Point source vs. non-point source Legal liability? Tracking? How is this different in oil spills?
BOD: impacted by anything that will decompose aerobically
Dead zones: low DO levels (via BOD or thermal pollution)
Eutrophication: too much food (nutrients)
Cultural Eutrophication: anthropogenic
Pathogens: cholera and hepatitis (esp. after disasters)
Explain cholera mechanism: intestinal, shock dehydration, cure for infants: salt and sugar water
Fecal Coliform: e. coli from humans, used as an indicator species (see recent rains here)
Septic systems:
Septic tank: septage into leach field (elab into the trees)
Cesspool: deeper, raw sewage leaks into groundwater/ocean (e.g. puako)
Wastewater treatment:
Primary: sedimentation tanks
Secondary: bacterial breakdown
Tertiary: chemical breakdown (chlorine, ozone-only ozone kills viruses)
Module 42-Heavy metals and chemicals
Lead-heavy metal, damages brain, nervous system and kidneys, can be chelated from body using EDTA:
Arsenic (e.g. ant poison, mystery novel poison), found in well water in E. India/Bangladesh:
Often found where mining occurs:
n.b. no arsenic in Hawaii (why not?)
Mercury-organic Methyl Mercury and inorganic (thermometers) "elemental mercury"
Burning coal, gold refining, mining, battery production (Minamata:
https://en.wikipedia.org/wiki/Minamata_disease)
Limits to large fish consumption in pregnant women
"mad as a hatter" Milliners
Acid deposition:
Sulfur dioxide (SO2) and nitrogen dioxide (N2O)
"acid snow" and acid rain
also runoff into streams
Synthetics:
Pesticides with long decay rates (e.g. DDT)
Hormones and drugs:
Endocrine disrupters, not cleared by municipal water treatment systems
Perchlorates:
From rocket fuels (solid rockets, boosters)
PCB: Poly chlorinated biphenyls (recall the orcas from "poisoned waters"), fat soluble, bioaccumulation in orcas, used as an insulating fluid in transformers (n.b. fire departments use hazmat suits when a transformer catches fire)
PBDE: poly brominated diphenyl ethers-brain damage (TRIS in children's clothing as flame retardant)
POP: persistent organic pollutants
Module 43: oil pollution
Slow to decompose, settles to bottom of ocean, e.g. Exxon Valdez (captain was drunk on duty) and BP oil spill in Gulf of Mexico ("Deepwater Horizon")
Oil plumes to 3000' deep in ocean
Damage to fisheries, beaches and corals/seabed animals
Module 44: solid, thermal and noise pollution
Flotsam=floating stuff, jetsam=thrown (jettisoned) stuff
Garbage patch in pacific: pacific gyre
thermal pollution: usually associated with power plants (30% efficient, so 1000 mW power plant spews 2000mW of heat into water system)
Decreases DO levels, also thermal shock to smaller organisms
Noise pollution: serious threat to animals and humans
notice health impacts
dB (decibel scale): 210 dB = Saturn V rocket blastoff, 0 dB = anechoic chamber
>100 dB causes permanent hearing damage (ringing in the ears=dead cilia in cochlea)
Module 45: water pollution laws
Clean Water Act (CWA) 1972-protection and propagation of fish, shellfish and wildlife. Maintain and restore chemical, physical and biological props. of surface waters (n.b. not aquifers, n.b. economic impact of violations, externalized costs)
Safe Water drinking act (SWDA) 1974-EPA (formed under Nixon) est. max contaminant levels (MCL) (see list)
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