Environmental Unit One

Front 1

air pollution: definition, sources, legislation

Back 1

contamination of the air by noxious gases and minute particles of solid and liquid matter in concentrations that endanger health ---- sources are hydrocarbons, fossil fuels, insecticides---- legislation is clear skies initiative

Front 2

global warming and ozone depletion

Back 2

a slow, steady decline of the total amount of ozone in earths stratosphere.....the observed increase in the avg temp of Earth's atmosphere and oceans

Front 3

ground water pollution and 7 major contaminants

Back 3

any undesirable substance in groundwater that is not normally present or present in high enough concentrations that it is harmful
7 - microorganisms, organic matter, chemical wastes, nuclear wastes, thermal wastes, sediments, water from different sources

Front 4

solutions to groundwater pollution

Back 4

remediation - drill well and pump out contaminated groundwater / bioremediation - treat water using bacteria and other microorganisms

Front 5

risk analysis

Back 5

probability that something undesirable will happen
risk = death / population

Front 6

relative risk

Back 6

ratio of the observed deaths due to a certain disease in a given population that shares a certain characteristic divided by the expected deaths in a population of the same size that does not have the characteristic --- standard mortality ratio

Front 7

NEPA and Environmental impact statement

Back 7

NEPA - National Environmental Policy act which was supposed to encourage productive and enjoyable harmony between man and environment

EIS - inventory, analysis and evaluation of the effect of a planned project on environmental quality

Front 8

how is pollution measured

Back 8

1.density = mass/ volume
2.concentration - amount of substance per unit volume (mass/volume of a mixture)
3.flow rate - quantity = amount/time, can either be measured gravimetric (mass/time) or volumetric (volume/time)
4.retention time - average time the fluid spends in the container through which the fluid flows
5. materials balance - use the concept of a black box which can either be a separator or a blender to combine

Front 9

hydrologic system

Back 9

precipitation, percolation into groundwater, evapotranspiration, repercolation - movement of water between the land, oceans, and atmosphere

Front 10

what are reactors

Back 10

most processes in environmental engineering occur in reactors - 1. mixed batch reactors are fully mixing with no inflow but outflow
2. plug flow reactor - a continuous flow but no mixing all elements enter and exit in same order
one and two are not typical in nature, in nature when a dye enters into a plug at first water is clear than becomes more colored until it reaches maximum level then it diminishes until the end

Front 11

transpiration and evaporation

Back 11

trans - measured by large vessels filled with soil to determine the rate of moisture escape from soil by weight changes

evaporation - measured by an evaporation pan

Front 12

ground water movement

Back 12

specific retention - the rate of the volume of the water an aquifer can reatin against gravity
cone of depression - caused when a ground water table is depressed due to pumping
draw down of multiple wells - can interfere with each other and cause excessive drawdown

Front 13

porosity

Back 13

- the fraction of voids volume to the total volume of the soil - some soils may have substantial porosity but not all of this water is available because it is tightly tied to the soil particles

Front 14

explain the water table

Back 14

aquifer - a geological formation containing a substantial amount of ground water

water table - the surface between aeration and saturation

zone of aeration - soil pore spaces contain both air and water but the water from this zone cannot be used as a water supply source ( gravity water, capillary water, and hygroscopic moisture held here)

Front 15

ground water pollution

Back 15

-hard water from calcium and magnesium deposits which requires softening
-agricultural facilities
-acid mine drainage
-NAPL : nonaqueous phase liquids
-LUST - leaking underground storage tanks
-DNAPL : dense nonaqueous phase liquids