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PUBLIC HEALTH ASSESSMENT

PALMETTO RECYCLING, INCORPORATED
COLUMBIA, RICHLAND COUNTY, SOUTH CAROLINA


ENVIRONMENTAL CONTAMINATION AND OTHER HAZARDS

Data in this section are from the November 16, 1994 Remedial Investigation report and represents the latest information available for this site.

The tables in this section list the contaminants of concern. We evaluate these contaminants in thesubsequent sections of this public health assessment and determine whether exposure to them haspublic health significance. SCDHEC and ATSDR select and discuss these contaminants based upon the following factors:

  1. Concentrations of contaminants on and off the site.
  2. Field data quality, laboratory data quality, and sample design.
  3. Comparison of on-site and off-site concentrations with public health assessment comparisonvalues for (1) non-carcinogenic endpoints and (2) carcinogenic endpoints.
  4. Community health concerns

In the data tables that follow under the On-site and the Off-site Contamination subsections, thelisted contaminant does not mean that it will cause adverse health effects from exposures. Instead, the list indicates which contaminants will be evaluated further in the public health assessment.

The data tables and narrative include the following abbreviations:
  • CREG
= Cancer Risk Evaluation Guide
  • EMEG
= Environmental Media Evaluation Guide
  • RMEG
= Reference Dose Media Evaluation Guide
  • ppm
= parts per million
  • ppb
= parts per billion

Comparison values for public health assessments are contaminant concentrations in specific mediathat are used to select contaminants for further evaluation. These values include EMEGs,CREGs, and other relevant guidelines. CREGs are estimated contaminant concentrations basedon one excess cancer in a million persons exposed over a lifetime. CREGs are calculated fromEPA's cancer slope factors. EMEGs are derived from ATSDR Minimal Risk Levels (MRL), theestimate of a daily human exposure to a chemical likely to be without an appreciable risk ifnon-carcinogenic adverse effects, generally for a period of a year or longer. RMEGs aremedia-specific comparison values derived from EPA reference doses and are used to select contaminants of concern at hazardous waste sites.

Of the contaminants detected at the PRI site, we will evaluate arsenic, iron, lead, and manganese further. The remaining contaminants are not present at levels that represent a public health concern.

Toxic Chemical Release Inventory (TRI)

TRI was developed by the EPA from chemical release information provided by certain industries. The chemical release information is based on contaminants found in air, surface water, groundwater, and/or soil.

Project staff conducted a search of the TRI database for 1988, 1989, and 1990. The searchincluded the site and a 1-mile radius around the site. As the site was not operable during theseyears, no listing was found. No other facilities were identified within a 1-mile radius of the site as part of this search.

A. On-site Contamination

Soil

As part of the RI, CDM and the EPA collected soil samples from on-site locations to determinethe extent of contamination at the site. CDM and the EPA collected 17 surface soil samples and48 subsurface soil samples from on-site locations (Figure 4). The RI defines surface soil samplesas samples collected from 0" to 12" below the land surface; however, ATSDR defines surface soilsamples as those collected from 0" to 3" in depth. ATSDR's definition is representative of depthsof soil that people are most likely to be exposed to. Therefore, this Public Health Assessment willaddress the RI surface soil samples as Soil Samples (0-12 inches deep).

PRI is situated in the Piedmont Physiographic Province and the Carolina Slate Belt GeologicProvince of South Carolina. The soils around the site consist of residual soil (soils that areformed by mechanical and chemical weathering of rocks and other materials). Samples collectedfrom the site demonstrate that the soil is composed of gravel, sand, silt, and clay.

    Soil Samples (0-12 inches deep)

CDM collected 17 on-site soil samples (0-12 inches deep). These samples were collected fromprevious storage/disposal area and a former trailer parking area (Figure 4). The samples wereanalyzed for inorganic compounds.

Aluminum and lead were detected at levels higher than background concentrations. Theconcentration of aluminum in the soil is within the range that is expected for the eastern region ofthe United States; however, the concentration of lead in the soil is higher that the range expected. Table 2 presents the contaminants of concern identified for this medium.

TABLE 2:

ON-SITE SOIL SAMPLES (0-12 INCHES DEEP)*
ContaminantConcentration
Range - ppm
Location Of
Maximum
Value
Comparison Value
ppmSource
Aluminum5,600 - 10,000PR03
No Value
Lead6.3J - 6400D2
No Value
*
J
= Data Source: CDM Federal Programs Corporation, 1994 RI
= Estimated Value
    Subsurface Soil Samples

As part of the RI, CDM collected 48 on-site subsurface soil samples (Figure 5). CDM collectedon-site samples from known waste areas, around office buildings, and from other work areas. Samples were analyzed for volatile organic compounds, semivolatile organic compounds,inorganic compounds, pesticides, and Polychlorinated Biphenyls (PCBs).

Table 3 presents contaminants of concern identified for this medium. However, the concentrationof metals detected in the environmental samples fall within the range that would be expected in the Eastern United States.

TABLE 3:

ON-SITE SUBSURFACE SOIL SAMPLES*
ContaminantConcentration
Range - ppm
Location Of
Maximum Value
and Depth
Comparison Value
ppmSource
Aluminum1,200 - 19,000BH-10, 5 ft.
No Value
ArsenicND - 46JBH-02, 43 ft.20Chronic EMEG (Child)
BerylliumND- 2.9BH-01, 18 ft.0.2CREG
Cobalt1.2 - 110BH-07, 20 ft.
No Value
CopperND- 170JBH-01, 18 ft.
No Value
Iron2,300 - 72,000BH-07, 15 ft.
No Value
Lead2.8J - 160JBH-02, 28 ft.
No Value
MercuryND - 0.37JBH-01, 10 ft.
No Value
*
ND
J
= Data Source: CDM Federal Programs Corporation, 1994 RI
= The contaminant was not detected in the sample
= The value for the contaminated is an estimated value

Groundwater

The PRI site is located within the drainage basin for the Broad River. An unnamed tributarylocated north of the site receives runoff from the site. Water from the unnamed tributary flowsinto Dry Fork Creek within a few hundred feet of the site. The site topographic elevations rangefrom 235 feet above mean sea level (msl) in the northwestern portion of the site to 255 feet abovemsl. The topographic slope is toward the north, northeast, and east.

In 1983, SCDHEC conducted an initial assessment of the hydrogeological conditions at the PRIsite. SCDHEC collected water table measurements from five monitoring wells; this investigationfound that the depth to groundwater was 5 to 11 feet below the land surface and groundwaterflow beneath the site is to the southeast toward Dry Fork Creek. CDM confirmed this information as part of the RI.

As part of the RI, additional monitoring wells were installed to evaluate the hydrauliccharacteristics of the aquifers beneath the site. The wells were installed in clusters; each cluster iscomposed of one shallow, one intermediate, and one deep well. CDM installed two on-sitemonitoring well clusters (six monitoring wells) as part of the RI (Figure 6). Monitoring wellcluster #01 was used to determine the background levels of contaminants.

Table 4 presents the contaminants of concern identified for this medium. The concentrations ofaluminum, cobalt, manganese, and nickel detected in these samples are representative ofbackground levels in the eastern United States. Arsenic, iron, and lead levels detected exceed thebackground levels expected for these metals.

TABLE 4:

ON-SITE GROUNDWATER SAMPLES*
ContaminantConcentration
Range - ppb
Location Of
Maximum
Value
Comparison Value
ppbSource
AluminumND - 13,000MW-01S
No Value
ArsenicND - 38MW-02I3Chronic EMEG (Child)
CobaltND - 8.1MW-01S
No Value
Iron6,000 - 44,000MW-02I
No Value
LeadND - 15MW-02I15EPA Action Level
Manganese530 - 1,800MW-01I50RMEG (Child)
NickelND - 5,300MW-01I200RMEG (Child)
*
ND
S
I
D
= Data Source: CDM Federal Programs Corporation, 1994 RI.
= The contaminant was not detected in the sample
= Shallow monitoring well
= Intermediate monitoring well
= Deep monitoring well

Surface Water

In April 1993, the EPA collected two surface water samples from an excavation pit located in thetruck scale area on the PRI site (Figure 7). The EPA deemed that the level of contaminantspresent in the liquid in the pit were at levels that did not pose a threat to the environment or publichealth; therefore, the EPA pumped the liquid from the pit into a nearby tributary of an unnamedstream. After the EPA pumped the liquid out of the excavation pit, the EPA backfilled the pit with soil.

Table 5 presents contaminants detected in the liquid of the excavation pit. The EPA did not collect sediment samples from the excavation pit.

TABLE 5:

ON-SITE SURFACE WATER SAMPLES
ContaminantConcentration
Range - ppb
Location Of
Maximum
Value
Comparison Value
ppbSource
Dieldrin0.032JSW-070.002CREG
Iron260-370SW-07
No Value
LeadND-16SW-0715EPA Action Level
Manganese37 - 110SW-0750RMEG - Child
*
ND
J
= Data Source: CDM Federal Programs Corporation, 1994 RI.
= Not Detected
= Estimated Value

B. Off-site Contamination

Soil

As part of the RI, CDM collected 7 soil samples (0" - 12" in depth), and 14 subsurface soilsamples from off-site locations (Figures 4 and 5). The samples were collected to determinebackground conditions and the extent of site-related contaminants to have migrated off the site.

    Soil Samples (0-12 inches deep)

Off-site soil samples were collected from a drainage ditch along the southern border of the siteadjacent to Koon Store Road and from a suspected dumping area north of the site (Figure 4). The samples were analyzed for inorganic compounds.

Aluminum, arsenic, copper and lead were detected at levels greater than those expected ofbackground concentrations. The concentrations for aluminum, arsenic and copper were withinlevels expected for soils in the eastern United States. Table 6 presents the contaminants of concern identified for this medium.

TABLE 6:

OFF-SITE SOIL SAMPLES (0-12 INCHES DEEP)*
ContaminantConcentration
Range - ppm
Location
Of
Maximum
Value
Comparison Value
ppmSource
Aluminum4,600 - 7,800SS-04
No Value
ArsenicND - 3.9JSS-040.4CREG
CopperND - 11SS-04
No Value
Lead15.1 - 1,500SS-04
No Value
*
ND
J
= Data Source: CDM Federal Programs Corporation, 1994 RI
= The contaminant was not detected in the sample
= The value for the contaminated is an estimated value
    Subsurface Soil Samples

As part of the RI, 14 off-site subsurface soil samples were collected from locations along theeastern boundary of the site because these locations represent areas downgradient to the site(Figure 5). CDM analyzed the samples for volatile organic compounds, semivolatile organiccompounds, inorganic compounds, pesticides, and PCBs.

Table 7 presents contaminants of concern identified for this medium. The concentration of themetals detected fall within the range that would be expected in the eastern United States.

Groundwater

As part of the RI, groundwater monitoring wells were installed to evaluate the groundwater flowpatterns beneath the site. The wells were installed in clusters; each cluster is composed of oneshallow, one intermediate, and one deep well. CDM installed two off-site monitoring well clusters(six monitoring wells) as part of the RI (Figure 6).

Table 8 presents the contaminants of concern identified for this medium. The concentrations ofmanganese detected are below those expected as background levels; however, the concentrationsof aluminum, arsenic, cobalt, iron, lead, and mercury detected in this medium are higher than thebackground levels expected for these metals.

TABLE 7:

OFF-SITE SUBSURFACE SOIL SAMPLES*
ContaminantConcentration
Range - ppm
Location Of
Maximum
Value and
Depth
Comparison Value
ppmSource
Aluminum1,900 - 17,000BH-08, 35 ft.
No Value
ArsenicND - 56BH-03, 15 ft.
BH-08, 25 ft.
20Chronic EMEG (Child)
BerylliumND - 0.84BH-03, 15 ft.0.2CREG
Cobalt2.5 - 28BH-03, 30 ft.
No Value
Copper3.5J - 73JBH-08, 35 ft.
No Value
Iron11,000 - 50,000BH-03, 31 ft.
No Value
Lead3.6J - 18BH-08, 20 ft.
No Value
Manganese17 - 2,200BH-03, 31 ft.300RMEG (Child)
*
ND
J
= Data Source: CDM Federal Programs Corporation, 1994 RI
= The contaminant was not detected in the sample
= The value for the contaminated is an estimated value


TABLE 8:

OFF-SITE GROUNDWATER SAMPLES*
ContaminantConcentration
Range - ppb
Location
Of
Maximum
Value
Comparison Value
ppbSource
AluminumND - 20,000MW-03S
No Value
ArsenicND - 19MW-03S3Chronic EMEG (Child)
CobaltND - 25MW-03I
No Value
Iron4,600 - 42,000MW-03S
No Value
LeadND - 19MW-03I15EPA Action Level
Manganese290 - 1,600MW-03I50RMEG (Child)
MercuryND - 0.26MW-04I
No Value
*
ND
S
I
D
= Data Source: CDM Federal Programs Corporation, 1994 RI.
= The contaminant was not detected in the sample
= Shallow monitoring well
= Intermediate monitoring well
= Deep monitoring well

Surface Water and Sediment

CDM collected 2 surface water and 6 sediment samples at upstream and downstream locationsfrom the site to determine the extent of contaminant migration (Figure 7). Surface water andsediment samples collected from an unnamed tributary of Dry Fork Creek (SW-01 and SD-01)represent background sampling locations.

Table 9 presents contaminants of concern identified in surface water. The concentrations of ironand manganese detected in this medium represent background concentrations. The concentrations of aluminum detected exceed those representative of background levels.

Table 10 presents contaminants of concern identified in sediment. The concentrations of metals detected in this medium exceed those expected of background.

Table 9.

OFF-SITE SURFACE WATER SAMPLES*
ContaminantConcentration
Range - ppb
Location
Of
Maximum
Value
Comparison Value
ppbSource
Aluminum230 - 330SW-06
None
Iron1,000 - 3,000SW-01
No Value
Manganese49 - 610SW-0150RMEG (Child)
*
ND
= Data Source: CDM Federal Programs Corporation, 1994 RI.
= The contaminant was not detected in the sample


Table 10.

OFF-SITE SEDIMENT SAMPLES*
ContaminantConcentration
Range - ppm
Location Of
Maximum
Value
Comparison Value
ppmSource
Aluminum1,200 - 5,500SD-04
No Value
ArsenicND - 5.7JSD-020.4CREG
BerylliumND - 1.5SD-040.2CREG
CobaltND - 16SD-03
No Value
CopperND - 9SD-04
No Value
Iron5,000 - 32,000SD-04
No Value
Lead3.3J - 35SD-03
No Value
*
ND
J
= Data Source: CDM Federal Programs Corporation, 1994 RI
= The contaminant was not detected in the sample
= The value for the contaminated is an estimated value

C. Quality Assurance and Quality Control (QA/QC)

The data in this section are from the 1994 Remedial Investigation report and represents the latestinformation for this site. Quality Control and Quality Assurance (QA/QC) conclusions drawn forthis public health assessment are determined by the validity of the analysis and conclusions madeand the availability and reliability of the referenced information. SCDHEC assumes that adequatequality assurance and quality control measures were followed with regard to chain-of-custody,laboratory procedures, and data reporting. Overall, the data appears to be reliable. All data haveundergone a laboratory quality assurance review.

D. Physical and Other Hazards

As part of the 1994 site visit, project staff identified several physical hazards at the PRI site. Thesite is unrestricted and the partial fence that surrounds the site poses more of a physical hazard insome areas than it serves as a fence. It is heavily vegetative and this could create difficulities forpeople who may wander onto the site. The old office building is unrestricted and containshousehold/other debris that pose a physical hazard to anyone who may wander into the building; italso has broken windows and could injure someone that comes into contact with this area.

PATHWAYS ANALYSES

To determine whether nearby residents are exposed to contaminants migrating from the site,ATSDR evaluates the environmental and human components that lead to human exposure. Thispathways analysis consists of five elements: A source of contamination, transport through anenvironmental medium, a point of exposure, a route of human exposure, and an exposedpopulation.

ATSDR categorizes an exposure pathway as a completed or potential exposure pathway if theexposure pathway cannot be eliminated. Completed pathways have all five elements and indicatethat exposure to a contaminant has occurred in the past, is currently occurring, or will occur in thefuture. Potential pathways, however, have at least one of the five elements missing, but couldbecome completed. Potential pathways indicate that exposure to a contaminant could haveoccurred in the past, could be occurring now, or could occur in the future. An exposure pathwaycan be eliminated if at least one of the five elements is missing and will never be present. Acompleted exposure pathway and potential exposure pathways were identified for the PRI site. Table 11 identifies the potential exposure pathways. The discussion that follows incorporatesonly those pathways that are important and relevant to the site. We also discuss some of thoseexposure pathways that have been eliminated.

Contaminants may have migrated or may migrate from the former operational areas at the PRIsite in the future. The main sources of contamination appear to come from liquids and sludgesgenerated as a result of a lead reclamation operation. Generally, poor and illegal waste handlingpractices have lead to spills and on-site dumping that have impacted soils, surface water, andgroundwater. The soil pathway represents the most likely route of human exposures tosite-related contaminants. Exposures could occur through direct contact with the soil. Additionally, soil contamination could leach into the groundwater beneath the site.

A. Completed Exposure Pathways

Surface Soil

Past, current, and future exposure pathways may result from exposures to contaminated on-siteand off-site surface soil (0 - 3") at several points of exposure: the site, drainage ditches, andundeveloped areas. Surface soil samples meeting ATSDRs definition of surface soil samples werenot collected at the PRI site. However, soil samples collected from 0 - 12" indicate that contaminants are present in surface soil.

In the past, exposure to contaminants at the PRI site could have occurred to anyone who mayhave wandered onto the site or to on-site workers. While the site is not currently operable,available data do not indicate the type, if any, of dermal or respiratory equipment used by the PRIemployees. In addition, there is no data to indicate what types of exposures may have occurredand/or the length of exposures; therefore, adverse health effects from past exposures to on-sitesoils cannot be evaluated. Exposures could have occurred through ingestion, inhalation, ordermal contact with contaminated soil.

Currently, we believe that people occasionally trespass onto the site as evidenced by the amountof domestic garbage and debris on the property. We know that the site was used in the past as aparking area for recreational activities that occurred in the wooded areas surrounding the site. However, it is difficult to define an exposed population due to the lack of information pertainingto who may trespass onto the site or the frequency of the occurrence. Currently, the gate at theentrance of the site prevents cars from entering the site; therefore, we believe that the site is nolonger used as a parking lot for recreational activities and the numbers of occurrences oftrespassing may have decreased. However, people who enter the site or those who are exposedto contaminated off-site soil may be exposed to contaminants through incidental ingestion of ordermal contact with contaminated soil.

The RI identified that site-related contaminants have impacted off-site locations. The contaminantmigration is estimated to have resulted from surface water runoff from the site due to the site'stopographic features. The site slopes to the east and southeast toward Dry Fork Creek. The soilsfrom residential yards south and southeast of the site were not analyzed as part of the RI;therefore, we cannot estimate if contamination has impacted these areas. Presently, SCDHEC andthe EPA are evaluating the concentrations of contaminants detected in the off-site drainage ditchto determine whether removal actions are needed.

B. Potential Exposure Pathways

Surface Soil Pathway (0" - 3" in depth)

Past, current, and future exposure pathways may result from exposures to contaminated on-siteand off-site surface soil (0" - 3" in depth) at several points of exposure: the site, drainage ditches,and undeveloped areas. While no surface soil (0" - 3") exist, soil samples collected from (0" -12") indicate that contaminants are present in surface soil.

In the past, exposure to contaminants at the PRI site could have occurred to anyone who mayhave wandered onto the site or to on-site workers. However, we do not have adequate data tocharacterize the types or duration of exposures that may have occurred. Therefore, adversehealth effects from past exposures to on-site soils cannot be evaluated.

Currently, exposures to on-site and off-site soil could be occurring. The site is unrestricted andpeople who may wander onto the site could be exposed to contaminated soil through ingestion,inhalation, or skin contact with soil. Contamination was detected in the ditch between the site andKoon Store Road and people who walk in the ditch or children that play in the ditch could beexposed to contaminated soil through incidental ingestion, inhalation, or dermal contact with thecontaminated soil. However, surface soil samples were not collected as part of the RI. ATSDRdefines surface soils as soil from 0" to 3" in depth because it is representative of the depth atwhich most people would normally be exposed. Therefore, the potential for human exposures toconcentrations of contaminants found in on-site and off-site surface soil cannot be evaluated.

Table 11.

POTENTIAL EXPOSURE PATHWAYS
Exposure Pathway ElementsTime
SourceEnvironmental
Medium
Point of
Exposure
Route of
Exposure
Exposed
Population
PRISurface Soil(0-3 inchesdeep)On-Site
Off-Site
Ingestion
Dermal
Contact
Inhalation
Children
Adults
Workers
Past
Present
Future
PRISubsurfaceSoilOn-Site
Off-Site
Ingestion
Dermal
Contact
Inhalational
Children
Adults
Workers
Future
PRIGroundwaterOn-Site
Off-Site
Ingestion
Dermal
Contact
Children
Adults
Workers
Past
Present
Future
PRISurface
Water
and Sediment
Off-SiteIngestion
Dermal
Contact
Children
Adults
Workers
Past
Present
Future
PRISurface
Water
Excavation
Pit
On-SiteIngestion
Dermal Contact
Children
Adults
Workers
Past

If the site is developed in the future, people could be exposed to contaminants of concern throughincidental ingestion of or dermal contact with contaminated soil.

Subsurface Soil Pathway

If the site is developed in the future, exposures to contaminated subsurface soil may result at thePRI site. On-site and off-site areas represent likely points of contact. As the site is not currentlyactive, the potential for human exposures to subsurface soils is considered unlikely. Therefore,this public health assessment eliminates further consideration of the subsurface soil exposurepathway at this time. Should the area be excavated in the future, this pathway will be reevaluated.

Groundwater Pathway

Some of the contaminants present in on-site soil may leach into groundwater. Infiltration andprecipitation will aid in the leaching process. Once in groundwater, contaminants are transportedin the direction of groundwater, but at a slower rate. Groundwater flow beneath the site is to thesouth and southeast toward Dry Fork Creek.

As part of the RI, a private drinking water well survey was conducted. The RI identified 35private wells within a 1-mile radius of the site; of those wells, 20 are used as a drinking watersource and the remaining are used for irrigation or other household uses. Some residentsexpressed concerns that their private wells may be contaminated with site-related contaminants. Samples were not collected as part of the RI; therefore, this pathway cannot be evaluated for past,current, or future existing private well users.

In the future, exposures to contaminated groundwater could occur to anyone who installs aprivate drinking water well in the area of groundwater contamination. Exposures could occurthrough ingestion of or dermal contact with contaminated groundwater. However, the installationof a private well is considered unlikely since conditions at the site are not favorable for future development.

Surface Water and Sediment - Off-Site

Surface water drainage from the site is to the southeast toward Dry Fork Creek. During the RI,two surface water samples and six sediment samples were analyzed . One of these locations wasconsidered upgradient from the site and the others were downgradient from the site. Contaminants of concern were identified in the downstream samples.

Past, current, and future exposure pathways may result from exposures to contaminants detectedin surface water and sediment. Currently, there are no known routes of exposure associated withsurface water and sediments. However, this potential exposure pathway could become completedin the future to anyone who ingests or has skin contact with contaminated surface water andsediments. Past exposures cannot be evaluated due to lack of data from the past.

Surface Water and Sediment - On-Site Excavation Pit

A past potential exposure pathway exists for children or adults exposed to contaminants in surfacewater once contained in an on-site excavation pit at the PRI site. In 1993, the EPA determinedthat the contaminants in the pit were not at levels that threatened human health or theenvironment and pumped the water to a nearby tributary of an unnamed stream. After pumpingthe water from the excavation pit, the EPA backfilled the pit with soil. Before the EPAcompleted these actions, humans may have been exposed to contaminants through dermal contactor accidental ingestion of the water in the pit. Since we can neither define a receptor populationnor an exposure duration for this pathway, we are unable to assess this pathway and it will not bediscussed further in this public health assessment.

PUBLIC HEALTH IMPLICATIONS

A. Toxicological Evaluation

Introduction

In this section, we will discuss the health effects in persons exposed to specific contaminants,evaluate state and local health databases, and address specific community health concerns. Toevaluate health effects, ATSDR has developed Minimal Risk Levels (MRL) for contaminantscommonly found at hazardous waste sites. The MRL is an estimate of daily human exposure to acontaminant below which non-cancer, adverse health effects are unlikely to occur. MRLs aredeveloped for each route of exposure, such as ingestion and inhalation, and for the length ofexposure, such as acute (less than 14 days), intermediate (15 to 364 days), and chronic (greaterthan 365 days). ATSDR presents these MRLs in Toxicological Profiles. These chemical-specificprofiles provide information on health effects, environmental transport, human exposure, and regulatory status.

To determine the public health implications for this site, we considered several different exposurescenarios based on the age of the person exposed to the contaminants. The people that could beexposed to contamination are defined as:

1)adults are considered to be 18 years old or older and weigh 70 kilograms (kg). Thescenarios assume that adults ingest 2 liters of water per day (l/day) and ingest 100milligrams of soil per day (mg/day).
2)older children are considered to be 10 years old and weigh 35 kg. The scenariosassume that older children ingest 1 L/day of water and ingest 200 mg/day of soil.
3)younger children are considered to be 6 years old and weigh 16 kg. The scenariosassume that younger children ingest 1 L/day of water and ingest 200 mg/day of soil.
    Surface Soil (0-3 inches deep)

    In this scenario, we assume that adults or older children may trespass onto the site 2 times perweek for 10 years. And that younger children may trespass onto the site 3 times per week for fiveyears. We adopted the same assumptions for exposures to off-site soil contaminants.

    If the site is developed in the future, we considered a scenario in which people could be exposedto contaminants on a daily basis. Special consideration is given to young children under theseconditions because they may display the characteristics of a pica child (a child that ingests largeamounts of soil by mouthing or ingesting nonfood items). Pica behavior is most evident in children from 1-3 years old.

    Groundwater

    In our assessment, we evaluate a worse case scenario for groundwater exposure in the event thata private drinking water well is installed in a contaminated area. No data are available aboutexisting private drinking water wells and these were not included in this evaluation.

    Surface Water and Sediment

    In this scenario, adults or older children may have been exposed to contaminants in surface wateror sediments 2 times per week for six months over a 10 year period. We assume that youngerchildren may be exposed to surface water or sediments 4 times per week for six months over a 5 year period.

Arsenic

Arsenic is a naturally-occurring element found in the earth's crust. Pure arsenic is a graymetal-like material; however, this form is not found in the environment. Arsenic is usually foundcombined with other elements. Most arsenic compounds are white or colorless powders that donot evaporate. They have no smell and most have no special taste. It is used as a woodpreservative and in several types of insect and weed killers (ATSDR 1993).

This public health assessment identified a completed exposure pathway and potential exposurepathways for arsenic. Past, present, and future exposures could occur too anyone who ingests orcomes into contact with off-site contaminated soil. Potential pathways may be completed in thefuture if humans ingest of have dermal contact with contaminated groundwater, soil, or sediments.

ATSDR has established a chronic oral MRL of 0.0003 milligrams per kilogram per day(mg/kg/day) for arsenic. The MRL is based on a study of 17,000 people who were exposed to0.0008 mg/kg/day of arsenic in their food and water. No adverse human health effects wereobserved in this study. People exposed to 0.01 to 0.1 mg/kg/day of arsenic for several yearsexperienced darkening of the skin and the appearance of small "corns" or "warts" on their palms,soles, and torso. High levels of arsenic, 300 to 30,000 ppb, in food or water can cause stomachpain, nausea, vomiting, and diarrhea.

Under the assumptions stated in the introduction of this section, people exposed to arsenic at thelevels detected in on-site and/or off-site soil are not expected to experience adverse health effects.

If the site is developed in the future, a child that exhibits pica behavior may be exposed to arsenicat levels greater than the MRL. However, the concentration of arsenic that a pica child would beexposed to is less than levels known to cause adverse health effects in humans. More studies areneeded to determine what adverse health effects, if any, may occur from exposure to low levels of arsenic.

If a private drinking water well is installed in an existing groundwater contaminated area, humansmay be exposed to arsenic through ingestion or dermal contact with water. The dose that anadult and older children would receive from exposure to arsenic would slightly exceed the MRL;the dose younger children and infants would receive would exceed the MRL. However, the levelsof arsenic that a person would be exposed to are less than the levels known to cause healtheffects. No health effects are anticipated from dermal exposure to arsenic; however, more studiesare needed to determine what health effects, if any, may occur from ingestion of watercontaminated with low levels of arsenic.

The concentration of arsenic contamination detected in off-site sediments are not expected tocause adverse health effects.

Iron

Iron is essential in the human diet. The Recommended Daily Allowance for iron in the diet is10-18 mg/day. However, excess iron in the diet may result in adverse health effects. Ingestion oflarge amounts of iron may cause vomiting, liver damage, and renal failure. Excessive iron in thediet over time may lead to the accumulation of iron in the liver, disturbance of liver function, andeven cardiovascular effects (Klaassen 1986).

This public health assessment identified potential exposure pathways for iron. Exposure to ironmay occur in the future through the ingestion of or dermal contact with contaminatedgroundwater or off-site surface water or sediment.

ATSDR has not established an MRL for iron and the EPA has not established an RfD for iron. However, available data indicate that the levels of iron in surface water and sediment are notsufficient to cause health effects. The levels of iron present in groundwater are sufficient to causethe water to have a bad taste. No adverse health effects are expected from ingestion of iron orfrom dermal contact with iron. However, some people are genetically sensitive to iron and shouldconsult their physicians before consuming water with high levels of iron.

Lead

Lead is a naturally-occurring element which may be found in most environmental media. It has awide range of uses including storage batteries (automobile batteries) solders, pipes, variouschemicals, and gasoline additives (ATSDR 1990).

This public health assessment identified a completed exposure pathway and potential exposurepathways for lead. Humans may have been exposed to lead in on-site and off-site contaminatedsoil by ingestion or through dermal contact with the contaminated media. Potential pathways maybecome completed in the future if humans ingest or have dermal contact with contaminatedon-site and off-site soil and groundwater and/or off-site sediments.

ATSDR has not set an MRL for lead and the EPA has not set a reference dose for lead. However, lead may cause acute and chronic health effects. Major concerns from exposures focuson two chronic effects of lead toxicity: irreversible central and peripheral nervous system damagein children (manifested as learning difficulty); and, hypertension in adult males (studies disagree asto whether this effect is more pronounced in white or black males).

In assessing the scenarios for the PRI site, additional human data is needed to better evaluatepotential human health effects anticipated from exposures to the concentrations of lead detectedin the on-site and off-site media. Additional data such as sex, age, and dietary habits help todetermine the amount of lead that could be absorbed by the body and what toxicological effects may result.

Currently, individuals who ingest or have dermal contact with the concentrations of lead detectedin on-site and off-site soil or groundwater are not expected to experience adverse health effects.

If the site is developed in the future, young children or pica children may ingest contaminated soilat levels that could cause adverse health effects. Short-term health effects include minor changesin the chemistry of the blood. Studies indicate that intermediate exposures may cause minorchanges in blood chemistry, effects to the male reproductive system, and/or learning difficulty.

The EPA has not set an estimate of the human carcinogenic potency of lead. Studies indicate thatanimals that ingest lead salts demonstrate an increased rate of cancer. However, the potential, ifany, for humans developing cancer from the levels of lead at the PRI site are unknown.

Manganese

Manganese is a naturally occurring element. Small amounts of manganese are an essential part ofthe human diet. Some manganese compounds are used in the production of batteries and as acomponent of some ceramics, pesticides, fertilizers, and nutritional supplements (ATSDR 1991).

This public health assessment identified potential exposure pathways for manganese. Exposure tomanganese may occur in the future through the ingestion of or dermal contact with contaminatedon-site and off-site groundwater or off-site surface water.

The EPA established a chronic oral RfD of 0.005 mg/kg/day for manganese. The concentrationof manganese detected in groundwater exceed EPA's RfD for adults and children. Current studiessuggest that long term exposures to the levels of manganese found in groundwater may causemild neurological effects in older people. However, the scope of these studies is limited and morestudies are needed to fully assess the toxicological implications from human exposure to manganese.

The concentrations of manganese detected in surface water do not exceed the chronic oral RfD. Therefore, no adverse health effects are anticipated from incidental ingestion of contaminated surface water.

Dermal exposure to manganese in surface water and groundwater are not anticipated to result inadverse health effects.

Contaminants Not Considered of Public Health Concern

Based on available data, the following compounds are not present at levels considered to be ofpublic health concern: aluminum, beryllium, cobalt, copper, mercury, and nickel.

B. Health Outcome Data Evaluation

As no health outcome data is available for the Palmetto Recycling Incorporated site, there is nofurther discussion at this time.

C. Community Health Concerns Evaluation

The community was concerned that the abandoned scale pit was filled with water and posed aphysical hazard to anyone who may wander onto the site. As part of the activities at the site, thepit was filled and no longer poses a physical hazard. The site was restricted by a gate and an EPAidentifier sign was posted at the site's entrance.

As part of the RI, the EPA conducted a private well survey and determined the number ofhouseholds within a 1-mile radius of the site that utilize private drinking water wells. While thereare several private wells within a 1-mile radius of the site, the EPA and SCDHEC believe that thecurrent private drinking water wells are not located in an area that will be impacted by site-related contaminants.

Local residents wanted to know how the site may affect deer and livestock; they were referred tothe South Carolina State Veterinarian for answers to their concerns. Some residents were alsoconcerned about eating fish from the streams near the site; however, the residents and the EPAdetermined that people fish in the stream at locations upgradient from the PRI site.

A resident was concerned that children who wait for the school bus in front of the site may beexposed to harmful levels of lead. Additional data are needed to better assess the potential foradverse health effects associated with exposures to surface soil. As surface soil data becomeavailable, we will re-evaluate this concern.



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