AMOCO OIL COMPANY
BELLEVILLE, ST. CLAIR COUNTY, ILLINOIS
The Illinois Department of Public Health (IDPH) conducted a health consultation for the Amoco Oil Company site at the request of the Illinois Environmental Protection Agency (Illinois EPA). As part of that process, IDPH evaluated the available site information to determine if the site poses a public health hazard.
The Amoco Oil Company site is in Belleville, St. Clair County. The site is on the northeast corner of the intersection of Shiloh Station Road and Shiloh Station East Road (Attachment 1). The site is about 0.5 acres in size and consists of two properties leased to the facility operator. The first property is a narrow strip of land owned by the railroad between the railroad tracks and Shiloh Station Road East (Attachment 2). This part of the site consisted of five above ground tanks, an office, and a loading pit. The second portion of the site was a privately-owned grassy field north of the railroad tracks and was used to store ammonia nurse tanks. A ditch was constructed between the railroad tracks and the field.
The facility began rock phosphate fertilizer operations on the property in 1962 and liquid fertilizer operations began in 1965. The Amoco Oil Company site was discovered in 1982 when a complaint was filed with St. Clair County regarding the illegal storage and distribution of pesticides on the site (1).
In 1986, the Illinois EPA conducted a preliminary assessment. The concern then was potential groundwater and surface water contamination. Illinois EPA recommended that a site inspection be conducted (2).
In 1988, U.S. Environmental Protection Agency (USEPA) contractors conducted a site screening inspection. Four soil samples and four residential well samples were collected. At that time, five tanks used to store liquid fertilizers were observed with capacities ranging from 7,500 to 35,000 gallons. One tank appeared to store diesel fuel and an underground tank held approximately 560 gallons of gasoline. Bulk ammonia was also stored in nurse tanks on the site (3).
USEPA published an inspection report in January 1989 that described the facility as a custom blending and storage facility for fertilizers containing nitrogen, phosphorus, and potassium. No berms or containment structures had been constructed around the tanks and at the time of the federal inspection a green stain on the soil was noted.
In May 2001, Illinois EPA staff collected soil and groundwater samples. Soil samples were tested for volatile and semi-volatile organic compounds, pesticides, and inorganic compounds. Groundwater samples were collected from two private wells and tested for pesticides and inorganic compounds (1).
The nearest neighbors are across the street from the site. A small neighborhood of about twelve homes is to the south of Shiloh Station East Road. Currently, no barriers limit access to the site and some neighbors reportedly maintained gardens on or near the property in the past. Public water service is not available in this small area, so water is obtained from shallow private wells. A newer subdivision with public water was built about 0.5 miles north of the site.
An intermittent stream leads from this area to Loop Creek, approximately 1 mile southwest of the site. These streams are part of the Kaskaskia River watershed that eventually drains into the Mississippi River (Illinois EPA, 2000).
IDPH staff visited the site most recently on May 1, 2001. All of the structures have been removed. The rail line dividing the two site properties is still active. The area topography appears to slope to the southwest toward Loop Creek. Part of the southern portion of the site drains to a low area between two private properties. Two small lakes, Anderson Lake and Miller Lake, are west of the site and an unnamed pond is north of the site property. Most of the surrounding properties are agricultural fields and pasture.
IDPH compared the results of the environmental sampling with appropriate comparison values used to select contaminants for further evaluation for carcinogenic and non-carcinogenic health effects. Chemicals found at levels greater than comparison values or those for which no comparison value exists were selected for further evaluation. A discussion of each comparison value used is found in Attachment 3. Exceeding a comparison value does not necessarily mean that exposure to the chemical will cause adverse health effects. The chemicals of interest at this site are sodium and heptachlor epoxide in groundwater and polycyclic aromatic hydrocarbons (PAHs), arsenic, and lead in soil.
In 1988, groundwater samples were collected from four private wells. Two were collected north of the site, one was collected south of the site and one was collected from a private well on the site used by the operators. Some samples had elevated levels of sodium as high as 89 parts per million (ppm).
Illinois EPA staff collected samples from two nearby private wells in May 2001. The samples were analyzed for pesticides and inorganic chemicals. A trace of heptachlor epoxide (0.03 parts per billion) was found in one well. No other chemicals were found at levels greater than comparison values.
Three soil samples were collected in 1988 by USEPA, two north of the site near the ammonia nurse tanks and one south of the railroad lines in the area where aboveground tanks were located. No chemicals of interest were found in these samples.
In May 2001, fourteen soil samples were collected from areas in and around the site by Illinois EPA staff and analyzed for volatile and semi-volatile organic compounds, pesticides, and inorganic chemicals. Benzo(a)pyrene was found in the soil samples at levels ranging from 0.16 to 1.0 ppm. Other PAHs were found in the 2001 soil samples but not at levels that exceeded comparison values. Two inorganic chemicals were also found at levels greater than comparison values in the May 2001 soil samples. Lead was found at an elevated level of 83,400 ppm and arsenic was found at a level of 23 ppm (1).
IDPH evaluated surrounding environmental conditions and activities that could lead to exposure to determine whether residents living near the site have been, are being, or might be exposed to hazardous chemicals at the site. A chemical can cause an adverse health effect only if people come into contact with it at a sufficient level. This requires a contaminant source, an environmental transport pathway, a point of exposure, a route of exposure, and an exposed population.
An exposure pathway is considered complete if all these components are present and people were exposed in the past, are currently exposed, or will be exposed in the future. A potential exposure pathway is one in which at least one of the five elements is missing but could exist. If part of a pathway is not present and will never exist, the pathway is incomplete and can be eliminated from further consideration.
The neighborhood near the site uses groundwater for their water supply. For drinking water, we assumed that children drink 1 liter and adults drink 2 liters of well water per day.
Since no barriers exist to prevent site access, people trespassing onto the site could be exposed to chemicals in the soil. We estimated exposure based on a 20 kilogram child playing on the site and ingesting 200 milligrams of soil per day, 3 days per week, 9 months per year.
Many studies have shown that decreased sodium intake is a major dietary factor in reducing the risk of high blood pressure. People drinking from wells with sodium levels more than 20 ppm were encouraged by letter to speak with their physician if they have high blood pressure.
Heptachlor epoxide was detected in only one water sample. Based on our scenario, exposure to heptachlor epoxide would result in no apparent increased cancer risk or non-cancer adverse health effects. The exposure doses calculated were lower than those shown to produce adverse health effects (4).
Benzo(a)pyrene was detected in soil samples in 2001. Based on our scenario, exposure to this level of PAHs would result in no apparent increased cancer risk or non-cancer adverse health effects (5).
Arsenic was detected in soil samples in 2001 at a maximum value of 23 ppm. The average value of arsenic in the fourteen samples collected was 9.4 ppm. Based on our scenario, exposure to this level of arsenic in soil would result in no apparent increased cancer risk or non-cancer adverse health effects (6).
Lead was detected in soil samples in 2001 at a maximum value of 83,400 ppm. This was also the same location where the highest level of arsenic was detected. The next highest level detected was 279 ppm and the average value of lead in the other thirteen samples collected was 108 ppm. Based on our scenario, exposure to soil other than where the maximum value was detected would not be expected to cause adverse health effects.
Although it is not likely to occur, if a child were to routinely play in the area where the greatest level of lead was detected, exposure could result in increased lead uptake. The IDPH Lead Poisoning Prevention Code states that the permissible limit of lead in soil readily accessible to children is 1,000 ppm. Exposure to lead levels greater than 1,000 ppm in residential soil can increase lead levels in exposed persons.
Exposure to lead can cause adverse health effects, especially in young children, since it is a neurotoxin that permanently interrupts normal brain development. Lead has no known beneficial biological function and is known to accumulate in the body. No safe threshold has been identified. Children, especially those of preschool age, ingest more lead through normal hand-to-mouth activity, absorb more of the lead they ingest, and are most sensitive to its effects (7).
IDPH recognizes that children are especially sensitive to some contaminants. For that reason, IDPH includes children when evaluating exposures to contaminants and considers children the most sensitive population considered in this health consultation.
IDPH concludes that under current conditions, the site poses no public health hazard; however, a small area on the site has a very high level of lead in the surface soil. If neighborhood children were to play in this contaminated area routinely, they may increase their exposure to lead, a neurotoxin. Although some chemicals have been detected in the area groundwater in the past, they are not currently at levels that would be expected to cause adverse health effects.
IDPH recommends that Illinois EPA reduce the potential for persons to be exposed to the elevated levels of lead in the surface soil in one area of the site. Covering the contaminated area with gravel or restricting access to the site would reduce the potential for exposure.
Catherine Copley, MS
Illinois Department of Public Health
- Illinois Environmental Protection Agency, Division of Land Pollution Control. Freedom of Information file inspections in December 2000. Springfield and Collinsville, Illinois: Illinois Environmental Protection Agency.
- Illinois Environmental Protection Agency. Preliminary assessment for Amoco Oil Company, Belleville, Illinois. Springfield. 1986 November.
- U.S. Environmental Protection Agency. Screening site inspection report for Amoco Oil Company, Belleville, IL USEPA ID: ILD000670703. Developed by Ecology and Environment, Inc, Chicago. 1989.
- Agency for Toxic Substances and Disease Registry. Toxicological profile for heptaclor epoxide. Atlanta: US Department of Health and Human Services; 1993 April.
- Agency for Toxic Substances and Disease Registry. Toxicological profile for polycyclic aromatic hydrocarbons (PAHs). Atlanta: US Department of Health and Human Services; 1995 August.
- Agency for Toxic Substances and Disease Registry. Toxicological profile for arsenic. Atlanta: US Department of Health and Human Services; 2000 Sept.
- Agency for Toxic Substances and Disease Registry. Toxicological profile for lead. Atlanta: US Department of Health and Human Services; 1999 July.
This Amoco Oil Company health consultation was prepared by the Illinois Department of Public Health under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is 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
Environmental Media Evaluation Guides (EMEGs) are developed for chemicals based on their toxicity, frequency of occurrence at National Priorities List (NPL) sites, and potential for human exposure. EMEGs are not action levels, but are comparison values. They are developed without consideration for carcinogenic effects, chemical interactions, multiple route exposure, or exposure through other environmental media. They are very conservative concentration values designed to protect sensitive members of the population.
Reference Dose Media Evaluation Guides (RMEGs) are another type of comparison value. They are developed without consideration for carcinogenic effects, chemical interactions, multiple route exposure, or exposure through other environmental media. They 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.
Maximum Contaminant Levels (MCLs) have been established by USEPA for public water supplies to reduce the chances of occurrence of adverse health effects from use of contaminated drinking water. These standards are well below levels for which health effects have been observed and take into account the financial feasibility of achieving specific contaminant levels. These are enforceable limits that public water supplies must meet.
Lifetime Health Advisories for drinking water (LTHAs) have been established by USEPA for drinking water. They represent the concentrations of chemicals in drinking water that are not expected to cause any adverse, non-carcinogenic effects over a lifetime of exposure. These are conservative values that incorporate a margin of safety.