A Citizen's Guide
Pump and Trealf
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What Is Pump And Treat?
Pump and treat is a common method for cleaning up
groundwater contaminated with dissolved chemicals,
including industrial solvents, metals, and fuel oil.
Groundwater is pumped from wells to an above-ground
treatment system that removes the contaminants.
Pump and treat systems also are used to "contain" the
contaminant plume. Containment of the plume keeps it
from spreading by pumping contaminated water toward
the wells. This pumping helps keep contaminants from
reaching drinking water wells, wetlands, streams, and
other natural resources.
How Does It Work?
Pump and treat methods may involve installing one or
more wells to extract the contaminated groundwater.
Groundwater is pumped from these "extraction wells"
to the ground surface, either directly into a treatment
system or into a holding tank until treatment can
begin. The treatment system may consist of a single
cleanup method, such as activated carbon or air
stripping, to clean the water. (See A Citizen's Guide to
Activated Carbon [EPA 542-F-12-001] and A Citizen's
Guide to Air Stripping [EPA 542-F-12-002].) However,
treatment often requires several cleanup methods if the
groundwater contains different types of contaminants
or high concentrations of a single contaminant. The
approach to treatment may be modified as contaminant
concentrations decrease.
Holding
Tank
Clean Water
Example of a Pump and Treat System with Two Extraction Wells.
Once treated water meets regulatory standards, it may
be discharged for disposal or further use. For example,
treated water may be pumped back underground
or into a nearby stream, or a sprinkler system may
distribute the water over the ground surface to irrigate
soil and plants. Treated water also may be discharged
to the area's public sewer system for further treatment
at the local wastewater treatment plant. Other wastes
produced as a result of treatment, such as sludge or
used filters, are disposed of properly.
Is Pump And Treat Safe?
Pump and treat is a safe way to both clean up
contaminated groundwater and keep it from moving
to other areas where it may affect drinking water
supplies, wildlife habitats, or recreational rivers and
lakes. Although pumping brings contamination to the
ground surface, it does not expose people to that
contamination. A pump and treat system is monitored
to ensure the extraction wells and treatment units
operate as designed. Also, the groundwater is sampled
to ensure the plume is decreasing in concentration
and is not spreading.
How Long Will It Take?
Pump and treat may last from a few years to several
decades. The actual cleanup time will depend on several
factors, which vary from site to site. For example, it may
take longer where:
Contaminant concentrations are high, or the
contamination source has not been completely
removed.
• The contaminant plume is large.
Groundwaterflow is slow, or the flow path is complex.
How Might It Affect Me?
People living or working near the site may see
increased truck traffic while the system is being built
as drill rigs and construction supplies arrive at the site.
They also may hear the machinery used to drill wells
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or construct the treatment system. Treatment systems usually are designed to
minimize noise while operating. Because pump and treat cleanups can take a
long time, systems can be designed so that other site activities may continue
during cleanup. For example, the treatment system may be constructed in a
location as far as possible from an office building or parking lot. It also may be
enclosed by a fence or a shed so that it is less obvious.
Why Use Pump And Treat?
Pump and treat is used to remove a wide range of contaminants that are
dissolved in groundwater. Pump and treat typically is used once the source of
groundwater contamination, such as leaking drums and contaminated soil, has
been treated or removed from the site. It also is used to contain plumes so that
they do not move offsite or toward lakes, streams, and water supplies. Pump and
treat is the most common cleanup method for groundwater. It has been selected
or is being used at over 800 Superfund sites across the country.
Groundwater Pumping Wells
Groundwater Treatment Building
Indoor Treatment Facility
Outdoor Treatment Facility
Example
The Baird and McGuire
Superfund site in Massachu-
setts was contaminated when
chemicals stored in tanks leaked
into the soil and groundwater.
The contaminated groundwater
plume flowed offsite, contami-
nating and closing the town's
main water supply. Since 1993,
a pump and treat system has
been containing the plume and
cleaning up groundwater.
Pump and treat began after
much of the contaminated soil
at the site was excavated for
treatment. Eight pumping wells
were installed at the site (seven
still operate) typically pumping
a total of about 127 gallons
of groundwater per minute.
The treatment plant includes
a metals removal system, air
strippers, and activated carbon
units to remove a wide range of
contaminants. It also has filters
and a sludge disposal system.
Treated water is pumped
back underground at the site.
Groundwater sampling has
shown that treatment continues
to protect human health and the
environment by containing the
plume and removing contami-
nants. The system is expected
to operate well into the future.
For More Information
For more information on this
and other technologies in the
Citizen's Guide Series, contact:
U.S. EPA
Technology Innovation &
Field Services Division
Technology Assessment Branch
(703)603-9910
NOTE: This fact sheet is intended solely as general information to the public. It is not intended, nor can it be relied upon, to create any
rights enforceable by any party in litigation with the United States, or to endorse the use of products or services provided by specific
vendors. The Agency also reserves the right to change this fact sheet at any time without public notice.
United States
Environmental Protection
Agency
Office of Solid Waste and
Emergency Response
(5102G)
EPA 542-F-12-017
September 2012
www.epa.gov/superfund/sites
www.cluin.org
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