GIBRALTAR MANUFACTURING COMPANY
EAST ALTON, MADISON COUNTY, ILLINOIS
Site-related contaminants are selected for further evaluation, based on the following factors:
- Laboratory-determined concentrations in samples collected on and off the site.
- Review of the data quality, the field sampling techniques, the laboratory quality assurance and controls, and the sampling plan.
- Comparison of contaminant concentrations with background concentrations.
- Comparison of contaminant concentrations with environmental media comparison values.
Comparison values are contaminant concentrations used to select contaminants for further exposure evaluation (Attachment1). The values include, but are not limited to, Environmental Media Evaluation Guides (EMEGs) for chronic (CEMEG) orintermediate (IEMEG) exposures, Reference Dose Media Evaluation Guides (RMEGs), and Cancer Risk Evaluation Guides(CREGs).
No contamination pattern was identified from the December 1996, systematic, surface soil collection. Adjacent gridsamples often contained varying concentrations. All 63 surface soil samples were analyzed for lead. Six of the sampleswere also analyzed for arsenic, cadmium, and copper.
Lead was found most often at a level that exceeds the Illinois comparison value of 1,000 parts per million (ppm). Lead isespecially toxic to unborn and preschool children. As lower environmental lead action levels have been developed, publichealth efforts have focused on education to prevent lead exposures. Pregnant women should avoid lead exposure becauselead can cross the placenta and is extremely damaging to the developing nervous system.
Lead also can damage the adult nervous system. Shortly after lead enters the body, it travels in the blood to the liver,kidneys, and other soft tissue organs. Ultimately, lead is stored in bones and teeth.
The concentrations of lead found at this site ranged from 8.35 to 13,600 parts per million (ppm). IEPA staff compiled asummary of Illinois soil lead levels found in background samples in August 1994 . The statistics from this report (inppm) were:
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Table 1 shows the lead concentrations found in on-site soils during the December 1996 sampling event. Tables 2 and 3 listlevels of inorganic and organic chemicals found at the site and the appropriate comparison values. A comparison value hasnot been developed for every element or chemical, so Illinois-specific soil standards have also been included forcomparison purposes.
Ten samples exceeded the Illinois standard of 1,000 ppm for children aged 6 months to 6 years . The distribution oflead does not appear to be consistent over the area of the site. The areas with higher lead levels could be attributed to pastoperations, recent soil excavations, building demolition, naturally occurring metals in soils, operations on nearbyproperties, or vehicular exhaust.
Only one sample of the six analyzed for cadmium had a concentration greater than the comparison value for chronicexposure to children. The ores processed at this site may not have contained much cadmium. None of the cadmiumsamples exceeded the comparison value of 500 ppm for adult exposure. Cadmium is considered a cumulative toxin in thehuman body. The body stores cadmium in the kidney, and once a significant concentration is reached, kidney failure canresult.
The concentration of arsenic in only one sample exceeded the arsenic comparison value set for chronic exposure ofchildren. None of the six soil samples were greater than the comparison value for chronic exposure for adults. Arsenicdoes not accumulate in the body and is excreted rapidly. Chronic ingestion of arsenic is associated with skin changes andskin cancer. Inhalation of arsenic is associated with lung cancer.
Some copper concentrations exceeded those found in Illinois urban settings. Little is known about chronic copperexposure in humans. Most human toxicological information is based on workplace inhalation exposures. Acute ingestionof significant copper often results in vomiting, so absorption is limited. Some copper is needed in the diet for normalphysiological functions.
Because of the location of the site and site security, a child is not likely to trespass onto the site. If a child were to trespassonto the site twice a week over a five-year period and ingest soil containing the highest levels of cadmium and arsenic, thedose would not exceed levels associated with adverse health effects. The provisional tolerable intake (PTI) for lead , basedon a blood lead level of 10-25 micrograms per deciliter (µg/dL), developed by the U.S. Food and Drug Administration fora 10-kg child is 6-18 micrograms per day (µg/day). Children trespassing onto the site could be exposed to levels ten timesgreater than the PTI.
The only organic chemical exceeding a soil comparison value is benzo(a)pyrene (BaP). A trespasser would not receive adose that is associated with adverse health effects.
No off-site sampling was conducted. No other contaminant was found at levels exceeding comparison values.