It is often clear when quality of life provided to human inhabitants by the built

environment falls below a universal threshold.

  Slums – the quality of life for residents is reduced directly by the density

   of people in a given area coupled with non-functioning environments

 Some cases are less clear…

   when the causes for reduction in quality of life are not spatially proximal or of

  direct accessibility by sensory perception:

  – a low income neighborhood is near a dump site that accepts toxic       waste without proper containment measures.

  – rural areas that have chemicals leached into their groundwater as a     result of less-than-stringent transportation or were polluted in a time   when there were no rules on transportation of toxic substances and   people are still unaware of or trying to mitigate effects.