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TABLE OF CONTENTS
Ground Water
The purpose
of a well is to drill into the earth to gain access to ground water.
Ground water is simply water that flows beneath the earth's surface.
Many people mistakenly perceive this to be in large lakes or flowing
rivers buried deep underground. This is not what groundwater is
(although there can be ground water in these forms in caves, mines,
and other natural or man-made subterranean "pockets").
Ground water is actually water that is completely saturated into soil,
rock, or other geological formations. This water is in constant motion
as it slowly seeps under ground. This can be compared to water in a
sponge. If water is pored onto a sponge it will slowly saturate the
entire sponge. This is precisely how the ground water works, it
saturates the porous materials layer underground (known as the Zone of
Saturation). This layer extends downward until it reaches a layer of
impervious material that the water cannot penetrate. Here it would
absorb into all the cracks and crevices (a process known as deep
percolation) but go no farther as the layer is too dense and
non-porous to allow saturation. The top of the zone of saturation is
known as the water table. The ground materials above this point are
not saturated. Surface water slowly infiltrates through this layer
(known as the zone of percolation) until it reaches the water table
where it becomes ground water.
Ground water
behaves much like surface water in that it flows from high areas to
lower areas. As it reaches these lowland areas, it often escapes to
become surface water. This can occur in several ways. Natural springs
can exist in which the ground water simply breaks through to the
surface. It can also leak into streams and rivers. Many streams would
become completely dry during periods of drought if it weren't for
being constantly fed by the ground water which isn't as easily
affected by surface weather conditions. Ground water can also
penetrate to the surface to saturate and even flood areas (creating
wetlands). Because of this tendency to flow downhill and the fact that
water is constantly entering and leaving the ground water, the entire
layer of ground water is in constant motion. Due to the fact that this
water must move slowly through the rock and porous materials, it takes
long periods of time for it to move, often as long as a day just to
move a couple inches.
Why is Ground Water so Important
Ground water
plays a major role in the water cycle. In fact, ground water makes up
about 95 percent of the planet' unfrozen fresh water supply. In 1990,
West Virginians used an average of 728 million gallons of ground water
per day. Although only about 7 percent of this water was actually used
for consumption, in most rural areas of the state ground water is the
exclusive source of water for domestic use. The other 93 percent of
the total (per day) usage is for mining and industry (about 50
percent), livestock water supply, irrigation, etc. It is further
estimated that the entire water resource in West Virginia adds up to
about 23 trillion gallons of surface water and 90 trillion gallons of
groundwater. Ground water is also so important because of its many
advantages. A few examples of these advantages would include:
- Passage through soil results in filtration of particulate
matter, and absorption of organic compounds and some metals on
clay materials.
- Relatively safe from some types of pollution, especially by
airborne contaminants.
- Relatively constant temperature and quality.
- Supply is less dependent on weather variations, compared to
surface water.
- Spread of pollution is usually slow.
from "A
Plan to Protect the Groundwater Source of"
by W.V. Rural Water Association
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Due to its advantages as a water source and its overwhelming
abundance, ground water is a very important resource. Many people
across the state rely on it for their sole source of fresh, clean
water.
So, What's the Problem?
Ground water
is an excellent water source that requires little purification. People
are finally beginning to realize that this resource is in serious
danger of becoming contaminated from our activities. Any liquid that
finds its way to the ground can eventually enter the ground water
supply. For example, if one gallon of oil were to be dumped into the
ground water supply, it would contaminate nearly one million gallons
of ground water. Although the soil and other materials do naturally
purify most of the water as it strains through, some harmful materials
are allowed to pass through. Harmful materials may also be introduced
directly into the aquifers (porous material layer in which the ground
water exists) through contaminated wells, mines, caves, leaking septic
tanks, or any other faulty under ground storage tank. (Other
sources of contamination). Some of the more prominent potential
sources of pollution include:
- Hazardous waste dumps and landfills. About 500 uncontrolled
hazardous waste sites have been identified in West Virginia.
Facilities that store, treat or dispose of waste in impoundments
or waste piles, or that have spills, may also contaminate ground
water.
- Solid waste, in poorly designed and managed landfill sand
illegal dumps. There are at least 15,000 unpermitted open dumps in
West Virginia.
- Underground storage tanks. Slow gasoline leaks can eventually
pollute an entire community's water supply. It is estimated that
between 100,000 and 400,000 tanks may be leaking throughout the
country.
- Underground injection wells. These wells can range from simple
cesspools to high-tech brine disposal wells that may be thousands
of feet deep.
- Septic systems and cesspools. If improperly installed and
maintained, contaminants such as bacteria, viruses and nitrates
can seep down from the drain field into ground water.
- Acid mine drainage from abandoned coal mines.
- Fertilizers and pesticides, when overused or improperly
discarded.
- Improperly abandoned wells. Unplugged wells allow pollutants to
migrate from the surface or from deeper formation into fresh water
aquifers.
- Used motor oil, poured in backyards, streams, on roads or down
storm sewers can pollute ground and surface waters.
- Household waste products. Paint, varnishes, lawn chemicals, and
cleaning solvents poured down sinks or disposed of with ordinary
trash, can end up in landfills and eventually in the ground water.
from
"Ground Water Facts for West Virginians" by W.V. DEP
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Once ground water becomes contaminated, it is very difficult or even
impossible to remove the pollution. Since the water moves so slowly,
the pollutant is able to stay very concentrated in higher levels in
certain areas, instead of dispersing over the entire area as surface
water does. The pollutants could remain in an area, making the water
unusable, for a period of several years or more. After a period of
time, the contamination in the ground water will spread to the surface
water as well, through its natural outlets.
What can I do to Help?
Despite all the efforts of the Wellhead Protection Program and all
of the other governmental agencies involved in ground water
protection, little can be done without the help of the public. Nearly
all of the causes of pollution of ground water are caused by the
actions of individuals and industries. This natural resource could be
perfectly preserved if people were only to realize the harmfulness of
their actions. Although the government can regulate industry, and
prevent them from the most obvious of pollutions, it would be nearly
impossible to stop every action that results in harmful effects to the
ground water. So, community involvement is the only way to effectively
reduce ground water pollution.
There are five basic steps to protecting the ground water supply of
a well: (1). Form a team, (2). Define land area, (3). Identify
sources, (4). Manage land area, (5). Plan for future. All of these
steps demand cooperation and assistance from the affected community.
The first step to WHP is to form a team within the community. This
group will then work through the rest of steps and be responsible for
protecting the water supply and planning what to do in the event of an
emergency. It is important that this group have a wide variety of
people involved to represent the various interests and groups in the
community so that the entire community will become involved.
(Suggestions for Potential
Members of the team). Once this team has been formed, they must
define the exact wellhead protection area ("the surface and
subsurface area surrounding a water well or wellfield, supplying a
public water system, through which contaminants are reasonably likely
to move toward and reach such water well or wellfield"). Once
this area has been defined and mapped, the team must properly manage
the area and regulate activities that could cause pollution and plan for future methods to eliminate and prevent pollution. An
important goal the team should immediately focus on is preparing a
written plan describing their intentions, proper actions for
contamination emergencies, as well as basic information about the
well. (click here for an
example of what might go into this plan). To learn more about forming
a community wellhead protection team and a detailed description of
each of the five steps, click
here.
The W.V. WHPP is devoted to aiding communities or other groups in
forming their own WHPP for their community wells. Only through the
involvement of all those who use the water from the well can this
precious natural resource be preserved for future generations. If you
would like more information or would like to begin forming your own
WHPP, please contact
us.
This site maintained by the West Virginia Source
Water Assessment and Wellhead Protection Program. Please address any
comments or questions
to the program or the webmaster.
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