U.S. MINERALS, LLC
COFFEEN, MONTGOMERY COUNTY, ILLINOIS
In October 2003, the Agency for Toxic Substances and Disease Registry (ATSDR) was petitioned to evaluate the U.S. Minerals site in Coffeen, Illinois. Residents were concerned about exposure to site-related contaminants in air and dust. To respond to this request, the Illinois Department of Public Health evaluated existing environmental data to determine whether exposure to air and dust in neighborhoods near U.S. Minerals could pose a public health hazard.
U.S. Minerals occupies approximately 20 acres about 0.5 miles southwest of Coffeen, Montgomery County, Illinois (Figure 1). Previously, Stanblast Abrasives operated the facility. The plant has received coal combustion bottom ash (also referred to as boiler slag) from Ameren Energy Generating Company-Coffeen Station. U.S. Minerals stores bottom ash on the ground until it is processed. The processing includes drying, crushing and screening the material to make products that can be used for roofing shingle products, blasting abrasives, road base material, and filler for such products as seal coating, plastic, paint and ceramic tile. No ash has been shipped from Ameren to U.S. Minerals since May 2002 (Illinois EPA, 2003).
A small, unnamed tributary of Coffeen Lake bisects the site. At times the property has contained as much as eight acres of stockpiled ash, up to 45-feet deep, with at least eight more acres of site paved in ash. The piles of ash have been getting smaller over time according to Illinois EPA inspection reports.
Bottom ash material covers the surface of the site adjacent to the large unprocessed ash piles and the "fines" pile. The processing of the slag material, as well as the large unprocessed piles and "fines" pile, have been the source of numerous complaints about airborne dust.
Nearby residents have complained since the fall of 2001 about odors and dust coming from the plant. Several meetings with Illinois Environmental Protection Agency (IEPA) staff have been held since that time (Illinois EPA, 2002a). Reportedly, about 15 homes are affected. One nearby resident reported that in late 2002, the air emissions improved, but that odors and dust increased again in August 2003.
In February 2002, McCrone Associates performed a comparison analysis of coal slag dust from the facility, dust from an outside table from a nearby residential yard, and dust from inside a nearby home. McCrone Associates concluded that particle types found in the coal slag sample were also seen in the outside table sample, and, to a lesser degree, in the indoor sample (McCrone, 2002).
In November 2003, a nearby resident collected a composite dust sample from the surface of homes near the plant. The American Testing Company, Inc. analyzed the dust for 10 metals (AMT, 2003). The levels detected in the surface dust sample were consistent with Illinois soil background levels. No air emission data or stack test results were available for this consultation.
On May 2, 2002, four samples were taken from the coal combustion waste piles on the site. Samples included material from both the baghouse fines and from the larger coal combustion piles. The samples were analyzed for metals and inorganic chemicals (Illinois EPA, 2002b).
IDPH compared the results of each dust sample and coal combustion pile samples with the appropriate screening comparison values used to select chemicals for further evaluation for carcinogenic and non-carcinogenic health effects. Attachment 1 contains a brief description of each type of comparison value used in this health consultation.
The composite surface dust sample and coal combustion pile samples were compared with soil comparison values. Because none of the metals in any of the samples exceeded comparison values, no chemicals of interest were selected for further evaluation. No adverse health effects would be expected from exposure to the surface dust.
Although the dust sample and coal combustion pile sample results suggest that exposure to surface dust does not present a public health hazard, no data exists for the levels of metals in the air. This route of exposure was a concern of nearby residents, but could not be adequately evaluated with the available data. Based on the testing done to date, none of the metals analyzed were considered to be present at levels sufficient to be a public health concern.
Various options exist to evaluate the potential for exposure to metals in the air. A stack test at the facility could provide a worse case scenario for metals in air. Dispersion and dilution of the airborne material would be expected before it reaches nearby homes. Another option would be plant perimeter or residential ambient air sampling, but this sampling may not be adequate to capture data from periods of higher emissions.
Residents have expressed concern about the airborne dust that settles onto their cars and houses. They are concerned about whether exposure to the dust could cause adverse health effects. In particular, residents are concerned about exposure to beryllium; however, the results of the composite dust sample and coal combustion sample do not suggest that beryllium or any other metal exists in the dust at elevated levels. Without air sampling data, it is not possible to evaluate whether exposure to airborne metals poses a health hazard.
IDPH recognizes that children can be especially sensitive to some contaminants. For this reason, IDPH used exposure factors for children when evaluating exposures to metals in surface dust collected near the U.S. Minerals facility. Children are the most sensitive population considered in this health consultation. Based on the limited data available, children currently are not being exposed to chemicals in surface dust at sufficient levels to cause adverse health effects.
Based on the limited data available, IDPH concludes that exposure to residential surface dust near U.S. Minerals in Coffeen, Illinois, poses no public health hazard. No elevated levels of metals were found in samples from on-site waste piles. Because no air sampling data exist, exposure to metals in ambient air near the facility poses an indeterminate public health hazard.
- IDPH recommends that the Illinois EPA Bureau of Air supervise a stack test of airborne emissions at the U.S. Minerals facility.
- IDPH recommends that residents continue to report to Illinois EPA events of odors and airborne dust they believe are coming from U.S. Minerals.
IDPH will evaluate the public health implications of the results of the stack test or other sampling activities.
Illinois Department of Public Health
The Illinois Department of Public Health prepared this U.S. Minerals health consultation under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It was done in accordance with approved methodology and procedures existing at the time the health consultation was begun.
W. Allen Robison
Technical Project Officer
Superfund Site Assessment Branch (SAAB)
Division of Health Assessment and Consultation (DAC)
The Division of Health Assessment and Consultation, ATSDR, has reviewed this health consultation and concurs with its findings.
Chief, State Programs Section
SSAB, DHAC, ATSDR
- American Testing Company, Inc. Laboratory Analytical Report for Coffeen, Illinois 62017. Bedford Heights, Ohio. November 13, 2003.
- Illinois Environmental Protection Agency. Field Report for U.S. Minerals. Springfield, Illinois. October 14, 2003.
- Illinois Environmental Protection Agency. (2002a) Memorandum to Bureau of Land File - Stanblast Abrasives, Coffeen, Illinois. Springfield, Illinois. April 22, 2002.
- Illinois Environmental Protection Agency. (2002b) Memorandum to Bureau of Land File - Stanblast Abrasives, Coffeen, Illinois. Springfield, Illinois. June 17, 2002.
- McCrone Associates, Inc. Microscopical Examination of Three Dust Samples from Coffeen, Illinois. Westmont, Illinois. March 27, 2002.
Environmental Media Evaluation Guides (EMEGs) are developed for chemicals based on their toxicity, frequency of occurrence at National Priority List (NPL) sites, and potential for human exposure. They are derived to protect the most sensitive populations and are not action levels, but rather comparison values. They do not consider carcinogenic effects, chemical interactions, multiple route exposure, or other media-specific routes of exposure, and are very conservative concentration values designed to protect sensitive members of the population.
Reference Concentration (RfCs) are another type of comparison value derived to protect the most sensitive populations. They do not consider carcinogenic effects, chemical interactions, multiple route exposure, or other media-specific routes of exposure, and are very conservative concentration values designed to protect sensitive members of the population.
Cancer Risk Evaluation Guides (CREGs) are estimated contaminant concentrations based on a probability of one excess cancer in a million persons exposed to a chemical over a lifetime. These are also very conservative values designed to protect sensitive members of the population.