|
#1 The hydrologic cycle. Precipitation infiltrates
soil and recharges groundwater. Groundwater flows in a down gradient
direction through the soil matrix. Groundwater eventually flows into
a surface water body (wetland, lake, river, ocean). Water in the surface
water body evaporates into the atmosphere and condenses to form precipitation. |
|
(Groundwater flow demonstration: glass
container filled with sand and water.)
#2 Contaminant migration in groundwater. A contaminant
released to soil will migrate down to the groundwater table. The contaminant
will disperse in groundwater and migrate in the direction of groundwater
flow.
(Groundwater contamination demonstration:
food coloring is added to the groundwater flow demonstration to simulate
a released contaminant). The contaminant percolates into the soil until
it reaches the groundwater table. The contaminant then disperses in the
groundwater as is flows down gradient. |
|
#3 Land uses that contribute to groundwater contamination.
Agricultural;
commercial; industrial; residential; waste
management (i.e. landfills). The basic theme is that land use impacts groundwater
quality. |
|
#4 Contamination sources.
Landfill: Precipitation that infiltrates
the soil cover of an uncapped landfill will leach various contaminants
from the fill material. The leachate that exits uncapped landfills typically
contains solvents, petroleum constituents, and elevated metals. Landfill
leachate typically has a reddish brown color.
Groundwater impacted by landfill leachate
typically has an abnormal color, a foul odor and high turbidity (dissolved
solid content).
Residential: Residential septic systems
are designed to naturally breakdown sanitary wastes. If a septic system
fails, harmful bacteria may percolate into groundwater. Also, many household
products can adversely impact groundwater quality if they are disposed
of down the drain. Agriculture : Pesticide and fertilizer applications
impact groundwater quality. The use of many pesticides have been banned
because of their effect on groundwater. Livestock can also impact groundwater.
The organic wastes created by livestock can increase the nitrogen content
of groundwater. |
|
#5 Containers of common household products that
impact groundwater quality when released. |
|
#6 Industrial waste lagoon. Drums containing
various chemicals have been illegally disposed of. |
|
#7 Earthmoving equipment exposing fill material
at a landfill. |
|
#8 An underground storage tank removed from a
gasoline service station. Holes in the bottom of the tank are visible |
|
#9 Drums containing chemicals are stored on a
loading dock. The drums are leaking. |
|
#10 Agricultural field. Application of fertilizers,
pesticides, and improper storage of silage and manure can impact groundwater
quality. |
|
#11 View of a catchbasin. Groundwater may be
contaminated if household products are disposed of in catchbasins. |