PUBLIC HEALTH ASSESSMENT
H & L NO. 1 MUNICIPAL LANDFILL
DANVILLE, VERMILION COUNTY, ILLINOIS
This section of the public health assessment describes environmental sampling previouslyconducted at the site and identifies contaminants found in specific environmental media abovecomparison values. Comparison values are contaminant concentrations in specific media used toselect contaminants for further evaluation, such as Environmental Media Evaluation Guides(EMEGs), Cancer Risk Evaluation Guides (CREGs), and other relevant guidelines. The selectedcontaminants are evaluated in subsequent sections of the public health assessment to determinewhether exposure to them has public health significance.
|CREG||=||Cancer Risk Evaluation Guide|
|EMEG||=||Environmental Media Evaluation Guide|
Lifetime Health Advisory
|MCL||=||Maximum Contaminant Level|
Reference Dose Media Evaluation Guide
|ppb||=||parts per billion|
|ppm||=||parts per million|
EMEGs are media-specific screening values developed by the Agency for Toxic Substances and Disease Registry (ATSDR) for use in selecting environmental contaminants of potential health concern. EMEGs are based on Minimal Risk Levels (MRLs) and do not consider potential carcinogenic effects. CREGs are estimated comparison concentrations for specific chemicals based on one excess cancer in a million persons exposed over a lifetime. Maximum Contaminant Levels (MCLs) represent contaminant concentrations that USEPA deems protective of public health (considering the availability and economics of water treatment technology) over a lifetime (70 years) at an ingestion rate of 2 liters of water per day.
USEPA's Lifetime Health Advisories (LTHAs) represent the level of a contaminant in drinkingwater (with a margin of safety) at which adverse noncarcinogenic health effects would not beanticipated during a lifetime (70 years) of exposure. While MCLs are regulatory concentrations(enforcement standards), LTHAs are not. USEPA's Reference Dose (RfD) is an estimate of thedaily exposure to a contaminant that is unlikely to cause adverse health effects.
The data presented in this section is from a hydrogeological investigation completed in 1980 andan RI completed in 1986. On-site contamination refers to samples collected in the areas shownin Figure 3.
Groundwater Monitoring Wells
Figure 3 shows the number and locations of on-site monitoring wells, and Table 1 shows thecontaminants and concentration ranges. There are no aquifers in the study area. Silt, and sandand gravel lenses, occurring in the tills, may contain some water; however, these lenses are smalland discontinuous. Some of the lenses can provide enough water for individual local wells.
In 1978, IEPA installed five groundwater monitoring wells on the site. Four wells were less than26 feet deep, and the fifth, G-604, was 40 feet deep. Subsequently, five bedrock groundwatermonitoring wells were installed on the site in 1986. The concentrations of inorganic constituentsfound in laboratory testing of water samples collected from the bedrock monitoring wells did notexceed any comparison values.
No analyses for organic compounds were done in 1978; however, organic compounds wereanalyzed and detected in the groundwater during the 1986 RI (Table 1). There were four organiccompounds detected in the groundwater samples collected from the bedrock monitoring wells. These wells were drilled using potable municipal water known to have traces of chloroform anddichlorobromomethane. Therefore, it is reasonable to assume that the presence of thesecompounds in the groundwater samples may have been from the water used during drilling. Thesource of benzene is unknown and appears to be an isolated, low-level occurrence. There wereno pesticides or polychlorinated biphenyls (PCBs) detected in any of the bedrock wells on the site.
Leachate Monitoring Wells
Leachate monitoring wells were installed within the refuse to characterize the chemical quality ofsubsurface leachate. The organic and inorganic analyses are presented in Table 2. There were nopesticides or PCBs detected in any of the leachate monitoring wells.
The results of the air monitoring conducted at the site in September 1986 indicated that thehighest concentrations of volatile contaminants were associated with the seep areas on the site. The samples were collected in stainless steel canisters and analyzed by GasChromatography/Mass Spectrometry (GC/MS). These results are shown in Table 3.
Groundwater - Private Wells
In 1978, abandoned private wells east of the site were sampled. Although the inorganic sampleresults showed the quality of the groundwater was degraded in the private wells, there was noinformation to conclude that the contamination was caused by the landfill. The poor waterquality in the private wells probably was caused by wastewater from cesspools, or septic tanksand leachate fields, and the landfill leachate probably had little impact.
An unpleasant taste in drinking water caused the residents of four single-family homes on theeast side of the site to install their own water line to the city's public water supply in 1969. Subsequently, IEPA recommended total abandonment of their private wells in 1971. A fifthresidential well was abandoned in 1986 after water analysis showed that a low level of vinylchloride was present (Table 4). Vinyl chloride was thought to be a degradation product of thetrichloroethene found in leachate seeps and sediments along the southern border of the site. Bis(2-ethylhexyl)phthalate was also detected by the water analysis, but it was believed to be theresult of laboratory contamination or leached from plastic plumbing pipes. There were nopesticides or PCBs detected in the bedrock wells. IEPA and the Vermillion County HealthDepartment are uncertain whether the five wells have been properly abandoned (3,6).
Soil and Sediment (Residential)
Soil samples collected from a residential farm field east of the site contained trace levels ofmethylene chloride and acetone that are most likely attributable to laboratory contamination ofthe sample. However, a trace level of trichloroethene (TCE) was detected, which might beattributable to the site because the field is within the downstream drainage path of the middletributary where TCE has been found. This field also contained polycyclic aromatic hydrocarbons(PAHs) and the pesticide chlordane (Table 5). The potential for historical application ofincinerator ash and chlordane on the field should be addressed before concluding that soils in thisfield have been affected by the site. Inorganic compounds (metals) were elevated in sedimentsamples collected from residential ponds and yard seeps (Table 5).
The south tributary drains the site, I-74, and a housing cluster across I-74 southwest of thelandfill. It is the largest of the three tributaries to the Vermilion River potentially affected by thesite. Sediment sampling of this tributary did not indicate the presence of any volatile organiccompounds (VOCs) above comparison values; but trace levels of acetone and chloroform weredetected. These compounds are typical analytical laboratory contaminants and are not likely tobe attributable to the site. The pesticide chlordane was detected in the tributary's sediment, but itwas not found in sediment samples next to the site. Thus, other sources of chlordane, such asresidential use, are most likely responsible for the presence of this contaminant in the tributary. Inorganic sampling revealed only one contaminant with a concentration higher than the levelsfound for the upstream (background) sediment samples. Lead was detected at 28 ppm. Othermetals in the south tributary sediments may be collectively attributable to leachate from the siteand the former mining area. Also, the south tributary may be influenced by drainage from I-74and runoff from a nearby residential area that may have once used mine spoils as cover materialor as roadway bedding.
The middle tributary receives leachate from surficial seeps near the northeast corner of the site. The tributary originates at the site as a partial leachate collection system. Sediments from themiddle tributary were contaminated with VOCs. Table 6 reflects the compounds found in allthree tributaries; however, the bulk of these compounds and their higher concentrations weredetected in the middle tributary. The organic contaminants in this tributary were directlyattributable to the discharge of leachate from the site. No other significant sources wereidentified. In addition, the inorganic compounds (metals) detected were one to two orders ofmagnitude higher than the background sample. Again, this reflected the overall leachate qualityin the northern section of the site. This quality was directly attributable to past site operations(mining and solid waste disposal) with only minimal influence from off-site sources.
The north tributary drains the west and northwest areas of the site and a portion of the residentialarea west-northwest of the site. Sediment samples from both upper and lower locations of thetributary exhibit low levels of VOCs, semivolatile organic compounds (SVOCs), and chlordane. The trace levels of VOCs were probably attributable to laboratory contamination. The SVOCs,which were polycyclic aromatic hydrocarbons (PAHs), were detected in one sediment samplecollected at a discharge point of an old storm drain near the incinerator building (Health andSafety Garage abandoned in August 1986). Benzo(b)fluoranthene, benzo(a)anthracene,chrysene, and phenanthrene are typical combustion products not found in any other leachate,sediment, or surface water samples elsewhere on site. The highest concentration of chlordanewas found in this tributary's sediment sample.
Inorganic compounds detected in this tributary were similar to those in the other tributaries;however, concentrations of most metals in the north tributary were detected in trace amounts andat greater levels in the middle tributary.
Sediment (Vermilion River)
River sediment samples taken upstream of the site were similar to background sediment qualityin the south tributary. There appeared to be no significant alterations in the river sedimentquality in samples collected near the site at the south, middle, and north tributaries' confluencewith the river.
Surface water data for the Vermilion River, the north, middle, and south tributaries, and North,South, and Orange Ponds did not indicate any VOCs, SVOCs, inorganic compounds, PAHs,pesticides, or PCBs greater than comparison values were present in the water samples.
The greatest amount of organic contamination in off-site leachate was found in samples collectedin May 1986. Low levels of VOCs, including bis(2-chloroethyl)ether, were found in the middletributary. The samples were collected from orange leachate at an area where odors have been apersistent problem.
Fish from the Vermilion River west of the site were sampled in August 1986. The fish speciescollected represented bottom dwellers and feeders. All samples were analyzed for organiccompounds that might accumulate in fish flesh.
Chlordane concentrations were similar for fish captured upstream and downstream. Therefore,based on a limited database for fish, it cannot be concluded that the site is affecting the fishpopulation in the Vermilion River. Other potential sources of chlordane contamination includeoff-site soils and areas where chlordane may have been applied or spilled in an urbanized area. These sources of chlordane may eventually drain to the Vermilion River through sewers, stormrunoff and storm drains, and sewage treatment facilities. Chlordane is often found in fish fromIllinois lakes and streams. The total chlordane (alpha and gamma isomers) detected downstreamwas less than the U.S. Food and Drug Administration limits for this compound in fish (32 ppb vs.300 ppb). Thus, IDPH has not issued a health advisory for eating fish for this segment of theVermilion River.
Toxic Chemical Release Inventory (TRI)
A search was conducted of the USEPA Toxic Chemical Release Inventory (TRI) for the site andlocal area (7). This database contains information on environmental chemical releases fromactive industrial facilities (1987-1992). Table 7 summarizes environmental releases fromindustries near the site. This information was obtained to get a general idea if past or ongoingemissions from manufacturing facilities in the area may be contributing an additionalenvironmental burden to the site and the potential population of concern.
In preparing this public health assessment, IDPH relies on the information provided in thereferenced documents and assumes that adequate quality assurance and quality control measuresabout chain-of-custody, laboratory procedures, and data reporting were followed. The validity ofthe analysis and conclusions drawn for this public health assessment is determined by theavailability and reliability of the referenced information.
In the past, the site was accessible to the public, with people playing on the ball diamonds andneighborhood children riding all terrain vehicles on the site. A children's play area with swingsand slides was on the site, near the ball diamonds. Physical hazards consisted of exposedcrushed drums (exposed as a result of erosion) and leachate seeps containing site chemicalcontaminants. The ball diamonds were abandoned in the summer of 1986, and a fence was builtaround the site perimeter in May 1993. Public access to the site is restricted.
To determine whether nearby residents are exposed to contamination migrating from the site,IDPH evaluates the environmental and human components that lead to exposure. A exposurepathway consists of five elements: a source of contamination, transport through an environmentalmedium, a point of exposure, a route of human exposure, and an exposed population.
IDPH categorizes an exposure pathway as either completed or potential. Completed pathwaysrequire that the five elements exist and show that exposure to a contaminant has occurred in thepast, is occurring, or will occur in the future. Potential pathways, however, require that at leastone of the five elements is missing but could exist. Potential pathways indicate that exposure toa contaminant could have occurred in the past, could be occurring now, or could occur in thefuture. An exposure pathway can be eliminated if at least one of the five elements is missing andwill never be present. The discussion that follows incorporates only those pathways that areimportant and relevant to the site. Table 8 shows the completed exposure pathways for the site.
Private Water Supply Pathway
A completed exposure pathway resulted from past contamination of groundwater in residentialwells immediately east of the site. None of the wells tested is used as a drinking water sourcetoday, and so this exposure is no longer occurring. Only one private well was identified tocontain contaminants (vinyl chloride) above comparison values. Vinyl chloride was probably adegradation product of TCE that was found on the site. The remaining private wells exhibitedsecondary standard violations that might have made the water aesthetically displeasing, butwould not be a health concern.
In the spring of 1987, the residences east of the site were connected to a new contaminant-resistant, municipal water supply line. Therefore, current and future concerns of the availabilityof uncontaminated drinking water for this population have been eliminated. Because vinylchloride was the only contaminant of concern detected in the groundwater completed exposurepathway, it will be discussed further in the Public Health Implications section of this public health assessment.
Ambient Air Pathway
As mentioned in the Environmental Contamination section, air sampling was conducted both onand off the site during the RI. The air samples were collected at the on-site northeast seep and atoff-site residences, both upwind and downwind of the site. Although the air data showed thatlevels of VOCs detected downwind of the site were less than those detected on-site, theconcentrations were still above comparison values. In fact, upwind background air samples werealso above comparison values, but at concentrations less than all downwind sample data. The airin this area may also be influenced by vehicle traffic on Greenwood Cemetery Road and theproximity to the city and I-74. Past odor complaints by residents indicate that some site aircontaminants have migrated off the site at levels sufficient to be noticeable. Since some dataexist regarding this pathway before remediation, air exposure will be addressed further in thispublic health assessment.
The final completed exposure pathway is contact with contaminated soils and sediments on andimmediately east of the site. Exposure routes through dermal absorption, dust inhalation, andingestion are possible. However, it is unlikely that the presence of these contaminants adverselyaffects human health among residents in the area. This conclusion is based on the overall lowlevels of the compounds identified, the relatively isolated locations of the samples collected(within drainage ditches, in pond or stream sediments, sides or bottom of ravines, or insidemanholes), and the lack of any potential sustained direct or indirect human contact or significantroute of exposure (air, water, soil, or food).
The on-site sampling was limited and confined to sediment samples collected at seeps and thebeginning of the middle tributary. While the concentrations are higher than off-site samples, andthere is no doubt that the compounds have migrated off the site, it is difficult to assess thispathway further because of insufficient data.
Present and future exposure to contaminated soil and sediment should not be a concern since theleachate collection system has reduced the number of seeps observed on and off the site. Inaddition, a fence has been installed around the perimeter of the site to restrict access tounauthorized personnel. IDPH anticipates that once remediation is complete, natural processeswill further cleanse off-site areas and reduce compounds to background levels.
Exposure to leachate may occur off the site. Apparently, the current leachate collection system isnot capable of handling the excessive quantities of leachate and storm water generated afterheavy rainfalls. It is unlikely that the presence of the diluted leachate would adversely affectresidents who might be exposed. However, it is difficult to assess this pathway further becausethere are no current leachate data available for VOC contamination.
The only potential exposure pathway identified at this site is contact with leachate that couldenter tributaries. This would only occur during rain events, and exposure to contaminants isunlikely.
IDPH and ATSDR recognize that children are more sensitive to the toxic effects of mostchemicals. For that reason, IDPH evaluated children's exposures as well as adults whendetermining if exposures to site contaminants were harmful. Those discussions are presented inthe following section of this document.
In this section we will discuss the possible health effects in persons exposed to specificcontaminants, evaluate state and local health databases, and address specific community healthconcerns.
To evaluate health effects, ATSDR has developed a Minimal Risk Level (MRL) forcontaminants commonly found at hazardous waste sites. The MRL is an estimate of daily humanexposure to a contaminant below which noncancerous, adverse health effects are unlikely tooccur. MRLs are developed for each route of exposure, such as ingestion and inhalation, and forthe length of exposure, such as acute (less than 14 days), intermediate (15 to 365 days), andchronic (greater than 365 days). ATSDR presents these MRLs in toxicological profiles, whichare chemical-specific profiles that provide information on health effects, environmental transport,human exposure, and regulatory status. In the following discussion, ATSDR toxicologicalprofiles for vinyl chloride, benzene, carbon tetrachloride, chloroform, trichloroethane, polycyclicaromatic hydrocarbons (PAHs), and chlordane were referenced.
Past exposure to vinyl chloride occurred to persons who drank and bathed in contaminated wellwater. For adults, the estimated ingestion exposure dose slightly exceeded ATSDR's oral MRLof 0.00002 milligrams per kilogram per day (mg/kg/day) for chronic exposure to vinyl chloride(8). IDPH assumed that 100% of the vinyl chloride would be completely absorbed daily fromthe gastrointestinal tract. Because the exposure was so low, people are not likely to experienceharmful health effects from the past use of the contaminated drinking water. Estimates oflifetime cancer risk suggested a low increased risk of developing cancer over a lifetime foradults. This estimated cancer risk assumed that exposure to adults would be every day for a totalof 10 years. Since 1987, no resident has used contaminated water for domestic purposes.
Some residents and ball players were exposed to benzene by inhalation. Before the city stoppedthe use of the site as a park (playground and 3 ball diamonds) in 1986, people were most likely exposed to some air levels of benzene on and off the site. Off-site benzene air levelsshould have decreased since an underground leachate collection system was installed in 1992. This installation has reduced the leachate seeps and groundwater migration off the site.
No comparison values exist for benzene; however, an approximation of the RfD can be madeusing the results of an animal inhalation experiment and a safety factor of 1,000. This includes along-term lowest observed adverse effect level (LOAEL) for blood system changes such asanemia, lymphopenia, and bone marrow hypoplasia in mice (Snyder et al. 1980) (9). ThisLOAEL represents the lowest dose of a compound that produces an observable adverse effect ina particular living organism. The estimated RfD is about 0.02 mg/kg/day. The anticipated doseresulting from the inhalation of the contaminated air on and off the site falls well below this RfD. This anticipated dose also considered children (10 years old) play on the site 5 days a week for40 weeks each year. IDPH assumed that at least 60% of the inhaled benzene was absorbed intothe body. No apparent increase in cancer risk is expected with this exposure scenario.
Like benzene, people were potentially exposed to carbon tetrachloride on and off the site throughinhalation. Neighborhood children playing on the site were most likely exposed at levels greaterthan other age groups. An approximation of the RfD was determined by using the results ofsome intermediate animal inhalation experiments (no chronic studies were available) and a safetyfactor (1,000-10,000). This includes a LOAEL for systemic changes (cirrhosis-liver disease) inrats (Adams et al. 1952) (10) and a LOAEL for neurological changes (narcosis) in humans(Heimann and Ford, 1941)(10). Hence, these data give a RfD range between 0.0009 and 0.0013mg/kg/day. The anticipated dose resulting from the inhalation of off-site carbon tetrachloridelevels falls at or below this range; however, the on-site anticipated dose exceeds this rangeslightly. IDPH assumed that at least 75% of the carbon tetrachloride inhaled was absorbed intothe body (10). Estimates of lifetime cancer risk suggest no apparent increased risk for peopleexposed to off-site concentrations of carbon tetrachloride; however, a low increased risk forchildren to develop cancer over a lifetime might occur under the conservative exposure scenariogiven.
Currently, no chronic inhalation comparison value exists for this compound. To evaluatepossible health effects of low level exposure, the following assessment was done. A chronic oralMRL of 0.01 mg/kg/day was used to derive an inhalation reference dose range for use inscreening (11). This range is between 5.8E-4 (0.00058) mg/kg/day and 1.1E-3 (0.0011)mg/kg/day. An RfD is an estimate of a daily exposure to the general human population that islikely to be without a noticeable risk of harmful effects during a lifetime of exposure. This doseassumed 100% absorption of the compound and intermittent exposure to on-site concentrationlevels. No adverse health effects are expected from this exposure scenario.
Since there was no trichloroethene detected above any comparison values off the site, thisevaluation only assesses intermittent exposure on the site. An inhalation no observed adverseeffect level (NOAEL) of 100 ppm (113 µg/m3) was reported for rats repeatedly exposed to thiscompound (12). The anticipated dose resulting from the inhalation of the air on the site fallsbelow the calculated reference dose of 0.0423 mg/kg/day. There is no increased risk ofdeveloping cancer from intermittent exposure (approximately 50% of time) to detected on-sitetrichloroethene air levels.
This compound is one of several polycyclic aromatic hydrocarbons (PAHs) found on the site andis considered to have the highest carcinogenic potential. Hence, a discussion of it will serve forthe other carcinogenic PAHs as well. The general population may be exposed to this compoundthrough air pollution, tobacco smoke, and food sources. It can exist naturally throughout theenvironment.
Exposure to PAHs may have occurred in the past to persons who contacted sediment in the seepscaused by the site. For adults and children, the amount of benzo(a)pyrene dermally absorbed from sediment does not exceed ATSDR's oral chronic MRL. Therefore, noncanceroushealth effects are not a concern. This was based on the assumption that only 3% of thecontaminated sediment is absorbed through the skin into the body (13).
Estimates of lifetime cancer risk using 1986 sediment sampling data suggested no apparentincreased risk of developing cancer over a lifetime for children, and no increased risk ofdeveloping cancer over a lifetime for adults. IDPH assumed that exposure to children would be12 years and adult exposure would be 30 years. These assumptions are very conservative since itis unlikely that exposure would be continuous throughout the year.
Past exposure to chlordane may have occurred through skin contact with contaminated sedimentsin leachate seeps. An estimate of long-term dermal exposure to chlordane was achieved byassuming 4.2% skin absorption and at least 50% exposure time (14). For adults and children, theestimated dermal dose did not exceed ATSDR's oral MRL of 0.00006 mg/kg/day for chronic exposure to chlordane. Because the level of exposure is so low, thesepeople are not likely to experience harmful health effects. Estimates of lifetime cancer risksuggested no apparent increased risk of developing cancer over a lifetime.
Although past exposure to some heavy metals may have occurred through skin contact with thecontaminated sediment, absorption through the skin is highly unlikely. No negative healthimpact is expected.
Exposure to bis(2-chloroethyl)ether may occur from leachate migrating to off-site tributaries. However, this potential exposure is limited to rainstorm events that overflow the leachatecollection system. Limited sampling data suggest that diluted leachate is not likely to causeadverse health effects. Estimates of lifetime cancer risk suggest no apparent increased risk ofdeveloping cancer due to exposure to on-site concentrations of bis(2-chloroethyl) ether.
There was no identified site-specific adverse health outcome data related to this site. Accordingto the local county health department, there are no records of studies that may have been done inthe community. There are no plans to perform an evaluation of health outcome data becauseexposure was limited to only five residences and possibly some intermittent exposure tounidentified ball players, spectators, and trespassers. The small size of the exposed populationwould not provide any statistically significant data.
Community health concerns are addressed as follows:
- Is the drinking water east of the site safe to use?
Contamination was detected in private drinking water wells east of the site. However, thisthreat was eliminated by the extension of a chemical-resistant drinking water line to servethose residences living east of the site.
- Is the contamination from the site harming the water quality of the Vermilion River?
Surface water, sediment, and fish samples were collected from the Vermilion River, andthe test results indicated no adverse impact. A variety of metals were present in the riversediment at concentrations considered normal in urban industrial areas. However, somewater samples exceeded Illinois Water Quality Standard concentrations for iron and manganese. These concentrations were attributable, at least in part, to past leachate flowfrom the site. Nevertheless, over the short term, they did not appear to adversely affectthe river. The operating leachate collection system should prevent any future migration ofsite contaminants into the river.
- Are the fish in the Vermilion River safe to eat?
IDPH issues health advisories when a fish sample is confirmed to contain more than theallowable amount of pesticides or heavy metals. The small concentrations of chlordanefound in the fish near the site did not warrant a health advisory.
- Is the air near the site safe to breathe?
In the past, air samples collected on and off the site showed that the highest levels ofVOCs detected were associated with the on-site seep area. Samples taken directly overleachate seeps showed concentrations that might, under certain conditions, cause short-term health effects, such as eye, nose, and throat irritation, headache, and nausea. Whilethe long-term health effects of breathing on-site contaminant concentrations are largelyunknown, there is a slight chance for some hypersensitive individuals to develop chronichealth problems. No apparent increased or low increased risk of developing cancer over alifetime is expected from exposure to concentrations of contaminants found on the site. Presently, exposure to on-site contaminants has been reduced by restricting site access andinstalling a leachate collection system. The number of odor complaints has decreased.