Ai  Citizen's Guide  to
 Excavation of Contaminated Soil
What Is the Excavation of
Contaminated Soil?

Excavation of contaminated soil from a site involves
digging it up for "ex situ" (above-ground) treatment or
for disposal in a landfill. Excavation also may involve
removing  old  drums  of chemicals and other buried
debris that might be  contaminated. Removing these
potential sources of contamination keeps people from
coming into contact  with contamination and helps
speed the cleanup of contaminated groundwater that
may be present.

How Does It Work?

Before excavation can begin, the contaminated areas
must be identified. This requires researching past
activities at the site to identify what contaminants may
have been released and where. The soil is then tested
to better define where contaminants are present.

Contaminated  soil   is excavated  using standard
construction equipment, like backhoes and excavator
trackhoes. The equipment chosen depends  on how
large and deep the contaminated area is, and whether
access is limited  by  the presence of buildings or
other structures that cannot be moved.  Long-arm
excavators can reach as deep as 100 feet below
ground, but excavations are generally limited to much
shallower depths due to safety concerns and difficulty
Soil piles are covered with plastic tarps during excavation.
Worker collects soil samples to confirm that soil left onsite is clean.

keeping the hole open. Sometimes soil is excavated
below the water table, which requires walling off the
contaminated area and pumping out the water to keep
dry during excavation.

If excavated soil will be disposed of in a landfill, it
may be placed directly on a dump truck for transport.
If it is to  be disposed of elsewhere on the site or
treated, it first may be stock piled on plastic  tarps or
in containers. The soil is then covered  with  tarps to
prevent wind and rain from blowing or washing it away
and to keep workers from coming into contact with
contaminated soil. Excavation is complete when test
results show that the remaining soil around the hole
meets established cleanup levels.

The excavated  soil  may be cleaned using a mobile
treatment facility  brought to  the  site  or disposed
offsite. If the soil is treated onsite, treated soil may be
used to fill in the excavated area. Clean soil obtained
from  other locations may be needed to fill in holes as
well.  After an excavation is filled in, the area  may be
landscaped to prevent soil erosion and make the site
more attractive.

How Long  Will It Take?

Excavating contaminated soil may take as  little as
one day or as long as several years. The actual time it
takes to excavate will depend on several factors. For
example, it may take longer where:

   The  contaminated area is large, very deep, or
    below the water table.

    Contaminant concentrations are high, requiring extra safety precautions.

    The contaminated soil contains a lot of rocks or debris.

    Buildings or site activities limit the movement of equipment.

    The site is remote, or the treatment and disposal facilities are far away.

 These factors vary from site to site.

Is Excavation Safe?

Handling contaminated soil requires precautions to ensure safety. Site workers
are trained to follow safety procedures while excavating soil to avoid contact
with contaminants and prevent the spread of contamination offsite. Site workers
typically wear protective clothing such as rubber gloves, boots, hard hats, and
coveralls. These  items are either washed or disposed of before leaving the
site to keep workers from carrying contaminated soil offsite on their shoes and
clothing.  The tires and exteriors of trucks and other earth-moving equipment
are also washed before leaving the site so that the soil is not tracked through
neighboring streets.

Workers  monitor the air to make  sure dust and contaminant vapors are
not present at levels that may  pose a breathing risk, and  monitors may be
placed around the  site to ensure that dust or vapors are not leaving it. Site
workers close to the excavation may need to wear  "respirators," which are
face masks  equipped with filters that remove dust and contaminants from the
air.  Contaminated soil is usually covered until  it can be treated or disposed of
to prevent airborne dust or being washed away with rainwater. Contaminant
vapors may be suppressed with foams or other materials.

How Might It Affect Me?

Nearby residents and businesses may notice increased truck traffic during soil
excavation and the noise of earth-moving equipment. Excavations are fenced
off to prevent entry to the area until it is backfilled and covered with clean soil.

Why Excavate Contaminated  Soil?

Excavation  is commonly used  where in situ cleanup methods will  not work
quickly enough or will be too expensive.  Offsite disposal and ex situ treatment
are often the fastest ways to deal with high levels of contamination that pose an
immediate risk to people or the environment. Excavation is also a cost-effective
approach for small amounts of contaminated soil.
                                       Soil excavation for offsite
                                       treatment and disposal was
                                       used to clean up the Federal
                                       Creosote Superfund site
                                       in New Jersey. Residential
                                       housing and a shopping mall
                                       had been built on the 50-acre
                                       property after a wood-treating
                                       facility closed in the 1950s.
                                       Creosote and waste chemicals
                                       that had been stored in
                                       lagoons were buried during

                                       Contamination was discovered
                                       in the 1990s. Between 2002
                                       and 2008, soil was excavated
                                       from as deep as  35 feet near
                                       93 homes. Some residents
                                       were relocated, and  18 homes
                                       were demolished to reach the
                                       contaminated soil beneath.
                                       A total of 275,000 tons  of soil
                                       from this area was transported
                                       offsite for treatment and
                                       disposal. Another 177,000 tons
                                       were excavated from the mall
                                       property. Clean soil was used
                                       to fill in the excavations.

                                       Throughout the work, workers
                                       monitored the air. Soil was
                                       covered with foam and  plastic
                                       sheets to reduce odors from
                                       the creosote. Trucks were
                                       cleaned prior to leaving the

                                       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
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
Office of Solid Waste and
Emergency Response
EPA 542-F-12-007
September 2012