United States
Environmental Protection
Agency
Region 5
77 West Jackson Blvd.
Chicago, Illinois 60604
Illinois, Indiana
Michigan, Minnesota
Ohio, Wisconsin
xvEPA
Chicago, Illinois
EPA Answers Questions Most
Often Asked by Residents
Lindsay Light II/RV3 North Columbus Drive Site
May 2000
INTRODUCTION
The purpose of this fact sheet is to provide
community residents and other interested
individuals with responses to questions frequently
asked about the Lindsay Light II /RV3 North
Columbus Drive Site cleanup.
What is Thorium?
Thorium is a metallic element. It is part of the
Thorium Decay Series, which is a series of
radioactively decaying elements. Both thorium and
the Thorium Decay Series are found naturally.
Where did the Thorium come from?
Thorium used on this site probably came from
India, Brazil, South Africa, Florida, the Carolinas
and Idaho in an ore called Monazite. Monazite is
found in beach and river deposits of minerals that
eroded from larger deposits and washed
downstream. These were mined, shipped to
Chicago, and chemically purified to obtain the
thorium and other elements necessary to produce
gas mantles. Unused ore and chemical wastes
are the site contaminants.
How was the radiation at the site discovered?
U.S. EPA had removed thorium contaminated soil
from an adjacent property over several past years.
When the ground was broken on the North
Columbus property, U.S. EPA obtained access on
the potential that it might also contain thorium
contaminants. Surveys showed there was also
contamination on this property.
How did U.S. EPA get involved?
U.S. EPA used its authority under the
Comprehensive Environmental Response, and
Compensation, Liability Act (CERCLA). CERCLA,
also know as "Superfund," is a law designed to
help cleanup abandoned waste facilities. Under
CERCLA, potentially responsible parties include
the owner and operator of a facility, any person
who at the time of the disposal owned or operated
the facility. In 1996, U.S. EPA ordered companies
to conduct the cleanup activities at 316 East
Illinois. In March 2000, U.S. EPA amended the
Order to include the North Columbus Drive site
and the owner of that property.
What is U.S. EPA's cleanup level and how was
it determined?
U.S. EPA relied upon a soil radium standard for
uranium and thorium sites found in Part 40, Title
192 of the Code of Federal Regulations (40 CFR
192). This standard is 5 picocuries per gram
(pCi/g) of total radium (radium-226 plus radium
228) over background in each 6-inch layer below
ground. 5 pCi/g is 11 radioactive decays per
minute per gram of soil. The background total
radium level near North Columbus Drive is 2.1
pCi/g. Therefore, the clean-up level for this site is
5 + 2.1 or 7.1 pCi/g.
What is involved in the cleanup?
Contaminated soils are first located using hand-
held gamma-ray detectors. These sites are
excavated with construction equipment until the
gamma ray detectors indicate the cleanup criterion
had been met. Soil samples are taken to confirm
this. U.S. EPA is then called to perform a
verification survey, which includes independently
performing a gamma ray survey and taking soil
samples. Each 100 square meter (about 120
square yard) area must meet the cleanup criterion
of 5 pCi/g of total radium (radium-226 plus radium-
228) over background (altogether 7.1 pCi/g). If the
cleanup criterion is met, the area is released for
unrestricted use. If the cleanup criterion is not
met, excavation continues until the criterion is met.
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What is the nature and extent of
contamination?
The primary contaminant is believed to be
radioactive thorium, but uranium and radium have
also been measured in these soils. All of these
are believed to have been present in Monazite ore
processed for thorium.
The original survey showed contamination in an
area about 125 feet by 125 feet in southwest part
of the site and contamination in scattered pockets
throughout the rest of the site. Excavations in the
eastern and southern parts of the site have shown
more contamination, which is now known to extend
under the sidewalks on Columbus Drive, Illinois
Street, and Grand Avenue.
What is being done to remedy the
situation?
Contaminated soils are being excavated, put in
metal boxes on flatbed semis and shipped via
railroad to the licensed disposal site in Utah. The
developer and potentially responsible parties are
cooperating with U.S. EPA in surveying the site,
providing health and safety surveillance, and
disposing of the contaminated soils.
Is the contamination contained?
Contaminated soils on site are being removed.
Materials have been found at the perimeter of the
site, and under sidewalks. These will be handled
under surveillance agreements and removed when
sidewalks, streets or utilities must be worked on.
So long as they remain covered by concrete and
asphalt they do not present a health and safety
concern. U.S. EPA hopes to survey perimeter
properties in the near future.
Some contaminated material was sent to an offsite
landfill. U.S. EPA will require a site survey to
determine the extent of contamination and will
require a remediation plan.
The City of Chicago has agreed to restrict access
to anyone exposing or working in the soils covered
by the sidewalks and streets. The City will give
U.S. EPA notice of anyone proposing to work there
and require anyone who must expose or work in
the soils beneath the sidewalks and street to
implement a health and safety plan, conduct
radiation surveillance and dispose of any
excavated contaminated materials.
How long do you estimate it will take to
complete the remediation?
The remediation program will continue as long as
necessary to remove the contamination.
Originally, this was projected to take eight weeks,
starting from early April. Potentially, the project
may take longer, therefore, an exact estimated
time frame can not given at this time.
What is the probability that adjacent lots
are also contaminated?
U.S. EPA knows that there is contamination under
some adjacent streets and in one nearby building.
A surveillance project is contemplated for other
perimeter properties to determine if additional
contamination is present beyond the known sites.
What are the potential health risks to the
environment?
U.S. EPA has required a health and safety plan
that should allow site cleanup to proceed without
danger to site workers, the general public and the
environment. Potential health risks include
exposure to gamma rays, inhalation of radioactive
dusts, ingestion of contaminated soil, skin
contamination and spreading of the contaminants
beyond where they are now. Controls for these
potential risks include maintaining levels As Low
As Reasonably Achievable so that doses to
workers are minimal and doses to the general
public are kept to background levels. There must
be no visible dust onsite, air concentrations to
workers and at the fence of the property must be
kept below regulatory levels, workers onsite must
not pick up contaminated soil on their skin or
clothes, and vehicles or equipment leaving the site
must not contain radioactivity above regulatory
levels. Other measures to control dust include the
"watering down" of the site during working hours.
What, if any, are the human health hazards?
The contaminants of concern are radioactive and
can raise the risk of cancer in specific organs and
can raise the risk for the body as a whole. This
may occur by exposure of the body to gamma
rays, by ingestion and inhalation of radioactive
materials, and by skin exposure to contaminants.
Since radiation exposure is a statistical risk there
will not be a certainty of cancer from exposure and
there will be no immediate, observable reactions.
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Is there a danger to the water supply
(ground and surface)?
Groundwater under the site is not used for
drinking. Additionally, the thorium materials are
very insoluble and past measurements have not
shown groundwater contamination. To be prudent,
U.S. EPA plans additional groundwater
measurements on this site. No water, whether
surface water or ground water, will be allowed to
leave the site without meeting release standards.
Is there the threat of runoff?
U.S. EPA's oversight has not shown runoff to be
an issue. If runoff was evident, U.S. EPA would
require that it be contained and dealt with in a safe
and healthful way.
If I walk by the site will I be in danger.
Using radiation meters, it has been determined,
that gamma rays on the surrounding sidewalks are
at background levels. Required air monitoring has
shown that concentrations are well below
regulatory levels for the general public. Fences
assure that a person passing by does not get close
enough to the contaminants to ingest them or get
them on their skin. U.S. EPA feels that the public
is well protected, but would take corrective
measures, if perimeter conditions showed
significant changes.
WEB SITES
This and additional updates can be found at the
following web sites:
www.epa.gov/region5/sites/
Scroll down through the list to find the Lindsay
Light II/RV3 North Columbus Drive site.
FOR ADDITIONAL INFORMATION
If you have questions about the information in this
fact sheet or would like additional information
about the Lindsay Light Sites, please contact the
individuals listed below:
Derrick Kimbrough
Community Involvement Coordinator
Office of Public Affairs (P-19J)
(312) 886-9749
kimbrough.derrick@epa.gov
Verneta Simon
On-Scene Coordinator
Superfund Division (SE-5J)
(312) 886-3601
simon.verneta@epa.gov
Fred Micke
On-Scene Coordinator
Superfund Division (SE-5J)
(312) 886-5123
micke.fredrick@epa.gov
U.S. EPA Region 5
77 West Jackson Boulevard
Chicago, Illinois 60604-3590
(800)621-8431
24-hour response number (312) 353-2318
Lindsay Light site-related information is available
at the following location:
Harold Washington Public Library
400 South State
Chicago, Illinois
Monday: 9:00 a.m. to 7:00 p.m.
Tues. and Thurs.: 11:00 a.m. to 7:00 p.m.
Wed., Fri., and Sat.: 9:00 a.m. to 5:00 p.m.
Sunday: 1:00 p.m to 5:00 p.m.
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