A 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 

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. Soil piles are covered with plastic tarps during excavation.

Worker collects soil samples to confirm that soil left onsite is clean.
United States Office of Solid Waste and EPA 542-F-12-007

Environmental Protection Emergency Response September 2012

Agency (5102G) www.epa.gov/superfund/sites

www.cluin.org

Example

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 

construction. 

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 

property. 

For More Information

For more information about 

this and other technologies 

in the Citizen’s Guide Series, 

visit:

www.cluin.org/remediation

www.cluin.org/products/

citguide

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.

• 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.