OLD LASALLE DUMP
LASALLE, LASALLE COUNTY, ILLINOIS
For the 1992 SSI, IEPA collected 4 off-site sediment samples (X102-105) from Huse Lake and 9 on-site soil samples (X106-114) (Attachment 2). One off-site soil sample (X101), which served as a background sample, was also collected from a nearby park (Attachment 3). The Illinois Department of Public Health (IDPH) was requested to interpret these results and comment on their potential health effects in April 1995.
IEPA conducted the November 1995 sampling to supplement the SSI data collected. Seventeen samples (S1-11, S13, S15-18) were collected that included: 2 surface water samples (S12, S14); 4 sediment samples (S11, S13, S15-16) (Attachment 4); 9 surface soil samples; and 2 surface soil/sediment samples. After reviewing the information reviewed, IDPH was unable to determine which 9 samples were surface soil and which 2 samples were surface soil/sediment. Surface water samples were only analyzed for pesticides and polychlorinated biphenyls (PCBs or Arochlors), and no contaminants were detected. Information was not available about the locations where soil samples were collected.
USEPA conducted a follow-up investigation in November 1996 to better characterize the area around a 1995 sample that contained 30,000 parts per million (ppm) Arochlor-1248. Six soil and 4 groundwater samples (S1-6 and GW1-4) were collected. Soil samples S1, S4, S5, and S6 were composites of 5 discrete samples (Attachment 5). All samples were collected from 2 to 4 inches below the surface, except sample S4, which was collected 5 to 12 inches below the ground surface. Soil samples were analyzed only for PCBs.
The concentration of each groundwater, soil, and sediment contaminant was compared with the appropriate comparison value used to select contaminants for further evaluation (Attachment 6). Soil and sediment samples were also compared with typical Illinois background inorganic soil constituents . Contaminants that exceeded comparison values or for which no comparison value was available were selected for further evaluation.
Tables 1 and 2 list information for samples collected in 1992 and 1995. Although people trespassing on site could be exposed to contaminants in soil and sediment through incidental ingestion and inhalation of contaminated dusts or dermal contact, exposure would most likely be small since the site is vegetated. However, IDPH evaluated the health risk for possible exposures to site contaminants by assuming the site is not vegetated, which represents the worst case scenario. Populations likely to be exposed are trespassers that include people picnicking or fishing at the site (Table 4).
Polycyclic aromatic hydrocarbons (PAHs) were detected at elevated levels in one soil sample in 1992 and in several samples in 1995. PAHs are formed during the incomplete burning of coal, oil, gas, wood, garbage, or other organic substances like tobacco and charbroiled meat. PAHs are found virtually everywhere in soil. In general, environmental concentrations are ranked as follows: urban levels are greater than agricultural levels, and agricultural levels are greater than rural levels. Some PAHs, such as benzo(a)pyrene (BaP), have been classified as probable human carcinogens. Levels of PAHs were present above comparison values in only one sample collected in 1992. The PAHs found at that location may have been the result of wood burning or charcoal ashe dumping. In 1995, PAHs were found in more samples, and levels were above background agricultural soil levels but were below background urban soil levels . IDPH evaluated the highest concentration of BaP detected in 1995 and concluded that no apparent health hazard exists for adults or children if occasionally exposured to site related PAHs.
Arochlors were another group of contaminants detected on the site. Arochlors are commercial PCB mixtures produced in the United States before 1977 . The toxicity of different Arochlors depends on the PCB congener present in the mixture. Congeners with a greater percentage of chlorine by weight are more toxic. Arochlor-1260 is 60% chlorine by weight and is considered the most toxic. Like some PAHs, Arochlors have also been classified as probable human carcinogens. They have been associated with skin, nose, and throat irritations in humans, and laboratory animals have displayed liver, stomach, thyroid gland injuries and decreased fertility in females. Some Arochlors detected on the site did not have a comparison value. The comparison value for PCBs is based on the toxicity of Arochlor-1260, which is used to evaluate relative toxicity of other Arochlors.
Arochlors were found during the SSI in several samples at the collected from the northern end of the site where several corroded and broken capacitors were either at the surface or protruding from the soil. The highest detected concentration of PCBs was 160 parts per million (ppm). Arochlors were found during the 1995 USEPA invetigation in 10 samples at concentrations ranging from 12 to 41 ppm and in an eleventh sample (S6) at a concentration of 30,000 ppm (Arochlor-1248). In 1996, the area surrounding sample S6 was examined further. Two samples contained elevated concentrations of Arochlor, and levels were not higher than 35 ppm. Because further characterization did not confirm the presence of high levels of PCBs previously found in the area, IDPH evaluated possible site-related exposure to PCBs based on the highest concentration detected in 1996. No apparent cancer risk or risk of other adverse health effects exist as a result of exposure to soils at the site.
Exposure to PCBs could occur from the consumption of contaminated fish. PCBs tend to bind tightly to soil. Movement of PCBs from soil to water seems unlikely, but contaminated soil could wash into the water. Any PCBs in water would not stay in the water column long but would deposit in sediment. Fish that eat along the bottom of the lake would ingest any PCBs present in the sediment. PCBs biomagnify through the food chain. That means that fish that eat bottom feeding fish would then become contaminated with PCBs at a higher level than the fish it consumed.
PCBs were not detected in sediment samples collected during the SSI. The highest concentration detected in 1995 was 41 ppm (Arochlor-1248). Although PCBs can accumulate in sediments through natural deposition from the atmosphere, samples collected in waters receiving industrial effluents have shown higher levels . Similarly, PCB concentrations in sediments closer to the site are expected to be higher than those further away from the site. Because of the mobility of fish, all of the fish in Huse Lake have the potential to become contaminated if lake sediments become contaminated.
Soil analyses conducted in 1992 for pesticides found heptachlor epoxide in one sample and 4,4'-DDE in another. Both compounds exist in soil because of past use of pesticides for both agricultural and nonagricultural purposes. Those contaminants were not detected at levels above comparison values in the 1995 sampling. If someone were exposed to site contaminants at detected levels, no carcinogenic or non-carcinogenic health risks would be expected from ingestion and dermal exposure to 4,4'-DDE and heptachlor epoxide.
In 1995, delta-BHC, also a pesticide used on crops, was detected in one sample at a level of 0.85 ppm. No comparison value for delta-BHC is available, but the average concentration in surface soil in Illinois is 0.02 ppm . Delta-BHC was not found in many samples (low detection frequency). If someone were exposued to the delta-BHC present on the site, no adverse health effects are expected as a result of occasional exposure.
Elevated levels of several metals, including calcium, cobalt, magnesium, chromium, copper, iron, and sodium have been consistently present at the site in soil and sediment; however, they were not found at levels that exceed comparison or background levels. Lead was detected during the investigations at levels greater than the IDPH guideline for soils in samples (X106-107, S5-7, S11). Exposure to elevated levels of lead is of particular concern for children because it may lead to nervous system damage, such as decreased intelligent quotient (IQ) scores, decreased concentration, and reduced growth. In adults, exposure may cause decreased reaction time, memory loss, and anemia . Kidney and brain damage is also possible in adults and children who receive high doses. Levels of lead on the site are unlikely to present a health hazard to children who only occasionally trespass and play in the area.
Groundwater samples were collected east of the site and are labeled GW1 through GW4 (Attachment 5). Laboratory analyses showed elevated amounts of lead and PCBs present in the samples. The results are shown in Table 3 .
Groundwater flows into Huse Lake and from there continues westward for a half mile to the Illinois River. The nearest groundwater well is about half a mile north of the site. IEPA records indicate that drinking water is probably not contaminated with site-related contaminants.
Groundwater samples were collected east of the site. Groundwater flows westward; therefore, the samples are not representative of possible groundwater constituents entering Huse Lake and the Illinois River. Concentrations of any possible contaminants are likely to be diluted upon entry into Huse Lake because of the large volume of water in the lake.
Lead was present in all groundwater samples, and the levels were above the USEPA action level. The action level for a contaminant is similar to the Maximum Contaminant Level (MCL), which has been established by USEPA for public water supplies and is deemed protective of public health, considering the economic feasibility of water treatment technology. Because lead is diluted in the lake and people are not likely to drink large amounts of lake water, exposure to lead from Huse Lake is not expected to be a health concern.
Arochlors were elevated in two separate, on-site groundwater samples; however, because of the dilution effect, concentrations in Huse Lake are not expected to be elevated. Although surface water was not tested for PCBs in 1996, they were not detected in the two surface water samples collected from Huse Lake in 1995. PCBs may have migrated to the lake since then, but a significant amount of contamination is not expected because PCBs tend to adhere to soil.