Chapter 17 Water Resources
in order from first detection of chromium in a groundwater sample to its remedration
1. determine the source of chromium 2. determine the geology of the site and the water table 3. determine the direction of the flow of groundwater 4. drill wells for sampling of groundwater for conformation 5. drill wells in front of the plume of contamintation and extract contaminated groundwater 6. process contaminated ground water
2 common ways groundwater originates and accumulates
1. from snowmelt seeping into the surface where it accumulates 2. percipitation seeping into into the surface where it accumulates
rank of reservoirs of freshwater on earth by volume, with that containing the highest volume first
1. ice caps 2. groundwater 3. lakes 4. rivers
in order of the smallest volume of surface freshwater to the largest on bottom
1. rivers 2. swamps 3. lakes
the federal goverment agency that regulates bottles water is the
FDA
pore spaces in the unsaturated zone of the subsurface are filled with
air
a large body of permeable saturated material through whichgroundwater can flow well enough to yield sufficient water to wells and springs
aquafier
the names used for any type of rock that retards the flow of water in an aquifer
aquatard
means that groundwater is confined and rises in a well because it is under pressure
artesian
limestone is primarily composed of
calcium carbonate (mineral calcite)
rainwater is slightly acidic because of the dissolved sulfur dioxide and
carbon dioxide
percipitation
clouds cool and water molecules bond together, eventually falling toward earth
the first step in constructing a contour map of a water table is to
collect and plot the evaluations of the water table in a avalable wells in the area
if groundwater is removed from an aquifer by overpumping , a cone of ____ will form
depression
as the water table ___, the origional aquafieris now above the water table and is said to be dewatered
drops
geologic settings where springs could occur
faults limestone aquafiers unoconformities
forms in some limestone caves as water flows down the walls and forms taverntine in thin layers that can become thicker over time
flowstone
groundwater found in crystraline rock like granite usually moves through what instead of pore spaces
fractures
a part of a stream that recieves water from the inflowof groundwater is
gaining stream
subsidence is the lowering of the elevation of the ground surface due to excessive pumping of
groundwater
when it is not raining or snowing in a wet climate, streams get their waste form
groundwater
a cone of depression will from if
groundwater is over pumped from an aquifer
stalacites
hang from the ceiling as they form from water dripping from the roof evaporates
are considered common groundwater contaminants
hazardous chemicals hazardous microbes
In the U.S., who uses the most water
irrigation
confined aquafier
is seperated from earths surface by rocks of low permeability
sinkholes, disapearing streams, and limestone pillars are characteristics of
karst topography
natural substances that can contaminate groundwater
lead and arsenic from mineralized rocks, radon
groundwater is a free water that exists beneath earths surface as a ___ rather then being chemically bonded in minerals
liquid
which of the following would be information that a geophysical survey could provide to a geologists
magnetism measurements electrical conductivity measurements measurements in the vaiation of gravity
when contamination enters groundwater, it typically
moves along with the flowing groundwater down the lsope of the water table
a spring is a place where water flows naturally from rock
onto the land surface
refer to the capacity of a rock to transmit a fluid
permeability
the rate of groundwater flow is strongly controlled by the ___ of the rock type
permeability
when contamination enters groundwater, it moves along witht he direction of the groundwater. the contamination takes on a paticular shape called a
plume
the percentage of rock or sediment that consists of voids or openings and is a measure of a rocks ability to hold water
porosity
3 important controls of how quickly water flows through rocks are
porosity, permeability, steepness of water table
infiltration
precipitation seeps into the ground surface
surface fractures that may indicate causes at depth
presence of limestone sinkholes disappearing streams
___ and snowmelt produce water that can flow across the surface as runoff
rainfall
infiltration of surface water into the groundwater system is one type of ___ that replenishes lost water
recharge
the term used to describe replenishment of groundwater either naturally or by human process
recharge
if groundwater wells among coastlines are overpumped
salt water intrusion occurs
which of the following materials would serve as an aquatard
shale
collapses of the roof of a cave can produce a
sinkhole
what contibutes water to a stream
snowmelt, direct percipitation, groundwater
lakes contain more freshwater than
swamps rivers
geological features that can be formed when groundwater interacts with limestone
taverntine, karst topography, sinkholes, caves
what information do hydro-geologists collect about the subsurface in their studies of groundwater
the amount the depth the setting the quality the direction of flow
if a perched lake is to remain permanent
the amount of inflow of water must beequal to or greater than the amount of outflow and losses to evaporation
unfined aquaifer
the waterbearing unit is open to earths surface and atmosphere, most common type
surface water can soak into the subsurface and become part of the groundwater if
the watertable is deeo enough so there is an unsaturated zone into which the water can seep, the surface material is permeable
characterisics of a ogalla aquifer
the western part is expected to be totally depleted by 2050 it has been overpumped it is an unconfined aquifer
permeability refers to the capacity of a geologic material to
transmit fluid
pore spaces in the saturated zone are filled with
water
Evaporation
water molcules rise into the atmosphere
condensation
water molecules join together as they rise in the atmosphere and form clouds
stalagmites
when water drips to the floor, building mounds upward