Types/Classification of Pollutants

  Thermal Pollution:  artificially warm water entering streams or lakes, raising T
        hot waste water from thermoelectric plants, manufacturing, processing, etc.
        40% of all water used in US goes to thermoelectrics (coal and nuke fired)
            steam in the closed cell loop and (most importantly) condensing/cooling
            thermal plume downstream from discharge, T usually drops off exponentially
        some aquatic biota are sensitive to small changes in water temperature
            young salmonid fry, for example, need cold water
        higher temperature also tends to lower the amount of dissolved oxygen
        those big milk bottle cooling towers designed to avoid thermal pollution

     Sediment Pollution:  rivers carry three types of material (aka "load)
          bed load (coarse bottom of stream), suspended mud, and dissolved ions
           e.g. too much silt and clay (mud) can cover gravels needed for spawing salmon
           logging increases mud through road building and associated landslides
           salt spread on roads as de-icer can contaminate groundwateródissolved ions
                high concentrations of Na and Cl can interfere with biochemical systems

     Biological/Genetic Pollution:  introduction of alien/nonnative/non-endemic species
           e.g. European zebra mussels in the Great Lakes clogging pipes
               send divers down to unclog drain pipes and water intakes
           e.g. Asian zooplankton in Puget Sound are too fast/too wiggly
               disrupts food chain at higher levels, reduces food for salmon
           e.g. pathogens like cryptosporidium in Minneapolis water supply

    Organic Pollution:  complex molecules of C bonded to H, O and/or N (and others)
        huge variety of organic compounds dumped into rivers and lakes
            herbicides, insecticides, some fertilizers, manufacturing wastes, etc.
        very difficult to generalize about these different pollutants; each is individual
            e.g. benzene, an aromatic hydrocarbon, a known carcinogen

    Nutrient Pollution:  water soluble compounds that accelerate plant growth
        Organic fertilizers (manure), measured as Total Dissolved Solids (TDS)
        Inorganic fertilizers: Phosphorous P and Nitrogen N in phosphates and nitrates
            e.g.  geese and lawn fertilizers dumping phosphates into Green Lake

    Inorganic Pollution:  substances that are not organic and not fertilizers
        e.g. heavy metals dumped into Tacoma waterways from Asarco smelting
        another incredibly complex category, no easy conclusions, each is individual.

    Radioactive Pollution:  unstable atoms = radionuclides decay to other atoms
        emit various types of radiation (Xrays, gamma rays, etc.) during decay
        radionuclides all around us and in us in small, natural quantitiesóno biggie
            e.g. granite rock, very radioactive; mortar between bricks, pretty hot
        BUT radionuclides have been concentrated artificially with bad results
            Uranium: .0002% in rocks, 20% in nuclear fuel.  Plutonium in bombs
            Bad actors:  radioactive Cesium Cs, Strontium Sr, Iodine I:  get in bones, teeth

Another way of organizing the information:

 Point Sources:  pollution comes from specific point or location
  e.g. sewer pipe into Lake Union; ship dumping foreign bilge into Puget Sound

 Non-point Sources:  pollution comes from wide area or region
  e.g. runoff from giant wheat farm; stormwater from street system
 

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