8.1: Sources of Pollutants

Learning objective: Identify differences between point and nonpoint sources of pollution

Essential Knowledge:

• A point source refers to a single, identifiable source of a pollutant, such as a smokestack or waste discharge pipe

• Nonpoint sources of pollution are diffused and can therefore be difficult to identify, such as pesticide spraying or urban runoff

Point Vs. Nonpoint pollutant sources:

Point source:

• A pollutant that enters the environment from an easily identified and confined place

• You can “point” to it

• Example:

  • Animal waste runoff from a CAFO (ammonia (N), fecal coliform bacteria)

  • Emissions from smokestack of a coal power plant (CO2, NOx, SO2, PM)

  • BP oil spill (hydrocarbons, benzene)

Nonpoint source:

• Pollutants are entering the environment from many places at once.

• Difficult to “point” to one individual source

• Example:

  • Urban runoff (motor oil, nitrate fertilizer, road salt, sediment)

  • Pesticides sprayed on agricultural fields are carried by wind and washed off large agricultural regions into bodies of water

Estuaries and bays are polluted by many nonpoint pollution sources from the large watersheds that empty into them

Pollutants vs. Pollution:

Pollutants:

• Specific chemicals or groups of chemicals from specific sources with specific environmental and human health effects

• Much more likely to earn you FRQ credit

• ON ANY POLLUTION_RELATED FRQ:

  • Specific pollutant names

    • Their sources

    • their environmental and human effects

    • their mitigation strategies

Pollution:

• Vague, nondescript term for any substance that is harmful to the environment

• never acceptable on an APES FRQ

• Exceptions:

  • Specific categories of pollution

    • THERMAL pollution

    • NOISE pollution

    • SEDIMENT pollution