PETITIONED PUBLIC HEALTH ASSESSMENT
NEWTOWN COMMUNITY
GAINESVILLE, HALL COUNTY, GEORGIA
Figure 1. TRI Facility Locations Around the Newtown Community (Area Map)
Figure 2. TRI Facility Locations Around the Newtown Community (Wide Area Map)
Figure 1. Age Distribution in Newtown
Table 1. Block Group and County Age Group Data, 1998 Projection*
| Age Group | Block Group 2 Population | % of total Block Group 2 Pop. | County Population | % of total County Pop. |
| Less than 6 years | 60 | 7.3% | 10,186 | 8.6% |
| 6-17 years | 115 | 14% | 20,088 | 17% |
| 18-24 years | 44 | 5.4% | 11,305 | 9.5% |
| 25-34 years | 125 | 15.3% | 17,577 | 14.8% |
| 35-44 years | 108 | 13.2% | 18,918 | 16% |
| 45-54 years | 108 | 13.2% | 15,944 | 13.5% |
| 55-64 years | 80 | 9.8% | 10,139 | 8.6% |
| 65+ years | 179 | 21.8% | 14,222 | 12% |
APPENDIX C: EVALUATION OF
ENVIRONMENTAL CONTAMINATION AND EXPOSURE PATHWAYS METHODOLOGY
EXPOSURE PATHWAYS TABLE
Quality Assurance
In preparing this report, ATSDR relied on the information provided in the referenced documents and by contact with community members, the City of Gainesville Public Utilities Department, Georgia Department of Natural Resources, Georgia Department of Human Resources, and the Environmental Protection Agency. ATSDR assumes that adequate quality assurance measures were taken during chain-of-custody, laboratory procedures, and data reporting. The validity of the analyses and conclusions drawn in this document are determined by the availability and reliability of the data.
Methods of Evaluating Potential Public Health Outcomes
The Agency for Toxic Substances and Disease Registry (ATSDR) has determined levels of chemical contamination that can reasonably (and conservatively) be regarded as harmless, based on the scientific data the agency has collected in its toxicological profiles. The resulting comparison values and health guidelines, which include ample safety factors to ensure protection of sensitive populations, are used to screen contaminant concentrations at a site and select substances that warrant closer scrutiny by agency health assessors and toxicologists. These contaminants of concern (COC'S) may slightly or greatly exceed comparison values, or they may be a health concern to the community. It is important to note that ATSDR's comparison values and health guidelines do NOT represent thresholds of toxicity. Thus, although concentrations are at or below ATSDR's comparison values may be reasonably considered safe, it does NOT automatically follow that any concentration above a comparison values will produce toxic effects. To the contrary, ATSDR's comparison values are intentionally designed to be lower, usually in orders of magnitude lower, than the corresponding no-effect levels (or lowest-effect levels) determined in laboratory studies.
In the first step of the COC selection process, the maximum contaminant concentrations are compared directly to health comparison values. ATSDR considers site-specific exposure factors to ensure selection of appropriate health comparison. If the maximum concentration reported for a chemical was less than the health comparison value, ATSDR concluded that exposure to that chemical was not of public health concern; therefore, no further data review required for that chemical. However, if the maximum concentration was greater than the health comparison value, the chemical was selected for additional data review. In addition, any chemicals detected that did not have relevant health comparison values were also selected for additional data review.
Comparison values have not been developed for some contaminants, and based on new scientific information, other comparison values may be determined to be inappropriate for the specific type of exposure. In those cases, the contaminants are included as contaminants of concern if current scientific information indicates exposure to those contaminants may be of public health concern.
The next step of the process requires a more in-depth review of data for each of the contaminants selected. Factors used in the selection of the COCs included the number of samples with detections above the minimum detection limit, the number of samples with detections above an acute or chronic health comparison value, and the potential for exposure at the monitoring location.
When screening individual contaminants, ATSDR typically compares the lowest comparison values available, usually the cancer risk evaluation guide (CREG) or chronic environmental media evaluation guide (EMEG) for the most sensitive, potentially exposed individuals (usually the elderly, children, and children who exhibit pica behavior) with the highest single concentration of a contaminant detected at the site. The conservative nature of ATSDR comparison values result in the selection of many contaminants as chemicals of concern that will not, upon closer scrutiny, be judge to pose any hazard to human health. However, ATSDR judges it prudent to use a screen that lets through many harmless contaminants rather that one that overlooks potential hazards to public health. The reader should keep in mind how conservative these values are when considering potential health implications of ATSDR's toxicological evaluations.
The comparison values used in this evaluation are defined as follows: The CREG (Cancer Risk Evaluation Guide) is a concentration at which excess cancer risk is not likely to exceed one case of cancer in a million persons exposed over a lifetime. The CREG is a very conservative CV that is used to estimate cancer risk. Exposure to a concentration equal to or less than the CREG is defined as an insignificant risk and is an acceptable level of exposure over a lifetime. The risk from exposure is not considered as a significant risk unless the exposure concentration is approximately 10 times the CREG and exposure occurs over several years. The EMEG is a concentration at which daily exposure for a lifetime is unlikely to result in noncancerous adverse health effects.
To determine whether nearby residents are exposed to contamination migrating from the site, the Agency for Toxic Substances and Disease Registry (ATSDR) evaluates the environmental and human components that lead to human exposure. An exposure pathway contains the following five elements: a source of contamination, transport through some kind of environmental medium (such as air, soil, or water), a point of exposure (such as a water well, or emissions stack), a route of exposure (eating, drinking), and an exposed population. In this assessment, ATSDR evaluates chemicals in the soil, air, and groundwater that people living in the nearby residences may consume or come in contact with.
| Pathway Name | Contaminants | Source | Environmental Media | Point of Exposure | Route of Exposure | Exposed Population | Time | Comments |
| Completed Pathways | ||||||||
| Past Air Emissions | VOCs Metals SVOCs |
Industry Traffic |
Air | Community ambient air | Inhalation | Child Adult |
Past | Past levels are uncertain. Air Modeling is recommended. |
| Current Air Emissions | VOCs | Industry | Air | Community ambient air | Inhalation | Child Adult |
Present | Completed exposure pathway. Current levels (after 1997) are below health concern. However, data may not represent air conditions in the community. |
| Surface Soil Contamination | Metals Pesticides |
Industry | Soil | Community soils | Inhalation Ingestion |
Child Adult |
Past | The only past sampling data available is incomplete and limited. More soil sampling is recommended. |
| Potential Pathways | ||||||||
| Soil Gas | VOCs | Landfill | Air | Residential | Inhalation | Child Adult |
Present | All methane levels detected below 1% LEL. Although not likely, the potential exists for future exposure. |
| Tap Water | Lead | Municipal Water Supply | Drinking Water | Residential | Ingestion Inhalation |
Child Adult |
Present | Lead is below Clean Water Act drinking standards. Lead was detected, but not at levels of health concern. |
| Stormwater Runoff | Bacteria Metals |
Industry Warm-blooded animals |
Stormwater Runoff | Residential | Dermal Inhalation Potential Ingestion (by children) |
Child Adult |
Present | Fecal coliform sampled at very high levels. Other metals are below health concern. Incidental ingestion may occur through dermal contact. |
| Eliminated Pathways | ||||||||
| Groundwater | VOCs Metals |
Industry | Groundwater | NA | NA | NA | Present | Groundwater is not used for drinking water. Exposure to groundwater contamination is highly unlikely. |
APPENDIX D: AIR ENVIRONMENTAL SAMPLING RESULTS AND ATSDR COMPARISON VALUES
Explanation of Comparison Values
Comparison Values (CVs)
The conclusion that a contaminant exceeds the comparison value does
not mean that it will cause adverse health effects. Comparison values represent
media-specific contaminant concentrations that are used to select contaminants
for further evaluation to determine the possibility of adverse public health
effects.
Cancer Risk Evaluation Guides (CREGs)
CREGs are estimated contaminant concentrations that would be expected
to cause no more than one excess cancer in a million (10-6) persons exposed
over lifetime. ATSDR's CREGs are calculated from EPA's cancer potency factors.
Environmental Media Evaluation Guides (EMEGs)
EMEGs are based on ATSDR minimal risk levels (MRLs) and factors in
body weight and ingestion rates. An EMEG is an estimate of daily human exposure
to a chemical that is likely to be without noncarcinogenic health effects over
a specified duration of exposure.
Reference Media Evaluation Guides (RMEGs)
ATSDR derives RMEGs from EPA's oral reference doses. The RMEG represents
the concentration in water or soil at which daily human exposure is unlikely
to result in adverse noncarcinogenic effects.
Risk Based Concentrations
Risk-Based Concentrations (RBCs) are the estimated contaminant concentrations
in which no chance exists for carcinogenic or non carcinogenic health effects.
The RBCs used in this public health assessment were derived using provisional
reference doses or cancer slope factors calculated by toxicologists of EPA's
Region III.
Table 1. Contaminants exceeding ATSDR comparison values from Georgia DNR air monitoring*
|
1997 Air Monitoring Data from the Fair Street School Monitor |
||||
| Contaminant | Range of Detection Levels (µg/m3)* | Detection Frequency | Total number of samples | Comparison value* |
| Benzene | 2.6-0.1 | 5 | 21 | .25 µg/m3 EPA RBC |
| Methylene Chloride | 46.9-3.8 | 2 | 21 | 4.1 µg/m3 EPA RBC |
| Hexachlorobutadiene | 7.5-7.5 | 1 | 22 | .09 µg/m3 EPA RBC |
| Arsenic | .018-.002 | 12 | 22 | .0045 µg/m3 EPA RBC |
| Cadmium | .0042-.00071 | 2 | 22 | .0001 µg/m3 EPA RBC |
Table 2. Contaminants of Concern for ATSDR Exposure Investigation
of Air in and around the Newtown Community
|
Contaminants Exceeding ATSDR Comparison Values in Analysis of SUMMA Canisters |
||||
| Contaminant | Range of detection levels (ppb)1 | Detection frequency | Total number of samples | Comparison value |
| Methylene Chloride2 | .34-5.5 | 10 | 10 | 300 ppb ATSDR Chronic EMEG 3 ppb ATSDR CREG |
| Benzene | .65-23 | 6 | 10 | .1 ppb ATSDR CREG 4 ppb ATSDR Intermediate EMEG |
| 2-Butanone | 1.2-1200 | 5 | 10 | 1000 ppb ATSDR chronic inhalation RMEG/RFC |
| Toluene | 1.1-1300 | 9 | 10 | 400 ppb ATSDR chronic EMEG |
| Freon 11 | .28-.38 | 10 | 10 | No Cvs are available |
| Freon 113 | .60-.89 | 8 | 10 | No Cvs are available |
| 4-Ethyl toluene2 | .78-.79 | 2 | 10 | No Cvs are available |
APPENDIX E: SOIL ENVIRONMENTAL SAMPLING RESULTS AND ATSDR COMPARISON VALUES
Figure 1. Georgia Department of Natural Resources Soil Boring Locations in the Newtown Area
Figure 2. University of Georgia Soil Boring and Monitoring Well Location Map
Explanation of Comparison Values
Comparison Values (CVs)
The conclusion that a contaminant exceeds the comparison value does
not mean that it will cause adverse health effects. Comparison values represent
media-specific contaminant concentrations that are used to select contaminants
for further evaluation to determine the possibility of adverse public health
effects.
Cancer Risk Evaluation Guides (CREGs)
CREGs are estimated contaminant concentrations that would be expected
to cause no more than one excess cancer in a million (10-6) persons exposed
over lifetime. ATSDR's CREGs are calculated from EPA's cancer potency factors.
Environmental Media Evaluation Guides (EMEGs)
EMEGs are based on ATSDR minimal risk levels (MRLs) and factors in
body weight and ingestion rates. An EMEG is an estimate of daily human exposure
to a chemical that is likely to be without noncarcinogenic health effects over
a specified duration of exposure.
Reference Media Evaluation Guides (RMEGs)
ATSDR derives RMEGs from EPA's oral reference doses. The RMEG represents
the concentration in water or soil at which daily human exposure is unlikely
to result in adverse noncarcinogenic effects.
Risk Based Concentrations
Risk-Based Concentrations (RBCs) are the estimated contaminant concentrations
in which no chance exists for carcinogenic or non carcinogenic health effects.
The RBCs used in this public health assessment were derived using provisional
reference doses or cancer slope factors calculated by toxicologists of EPA's
Region III.
Table 1. 1994 Georgia Department of Natural Resources Soil Analysis
|
Contaminants in soil above ATSDR comparison values (CVs) |
||||
| Contaminant | Range of detection levels (ppm)* | Frequency of detection | Total number of samples | Comparison value |
| Aluminum | 7900-27,000 | 8 | 8 | 4000 ppm ATSDR interim oral EMEG pica child 100,000 ppm ATSDR interim oral EMEG child 1,000,000 ppm ATSDR interim oral EMEG adult |
| Arsenic | 6.9-6.9 | 1 | 8 | .43 ppm EPA RBC 0.5 ppm ATSDR chronic oral CREG 0.6 ATSDR chronic oral EMEG/RMEG pica child 20 ATSDR chronic oral EMEG/RMEG child 200 ATSDR chronic oral EMEG/RMEG adult |
| Vanadium | 6.6-39 | 8 | 8 | 6 ppm ATSDR interim oral EMEG pica child 200 ATSDR interim oral EMEG child 2000 ATSDR interim oral EMEG adult |
Table 2. 1994 Soil Analysis conducted by University of
Georgia
|
Contaminants in soil above ATSDR comparison values (CVs) |
||||
| Contaminant | Range of detection levels (ppm)* | Frequency of detection | Total number of samples | Comparison value |
| Aluminum | 4350-42,600 | 24 | 24 | 4000 ppm ATSDR interim oral EMEG pica child 100,000 ppm ATSDR interim oral EMEG child 1,000,000 ppm ATSDR interim oral EMEG adult |
| Iron | 23,600-50,700 | 24 | 24 | 23,000 ppm EPA RBC |
| Lead | 468-468 | 22 | 24 | 400 ppm EPA RBC |
| Manganese | 117-217 | 24 | 24 | 1600 ppm EPA RBC 100 ppm ATSDR chronic oral RMEG pica child 3000 ppm ATSDR chronic oral RMEG child 40,000 ppm ATSDR chronic oral RMEG adult |
Table 3. ATSDR Exposure Investigation Soil Analysis
|
Contaminants above ATSDR comparison values, collected during ATSDR's exposure investigation |
||||
| Contaminant | Range of detection levels (ppm)* | Frequency of detection | Total number of samples | Comparison value |
| Aluminum | 7400-15,000 | 5 | 5 | 4,000 ppm ATSDR interim oral EMEG for pica children 100,000 ppm ATSDR interim oral EMEG child |
| Cadmium | 2.6-2.6 | 1 | 5 | 78 ppm EPA RBC .4 ppm ATSDR chronic oral EMEG pica child 10 ppm ATSDR chronic oral EMEG child 100 ppm ATSDR chronic oral EMEG adult |
| Iron | 9200-26,000 | 5 | 5 | 23,000 ppm EPA RBC |
| Lead | 28-99 | 5 | 5 | 400 ppm EPA RBC |
| Magnesium | 330-4200 | 5 | 5 | No comparison values are available |
| Manganese | 63-610 | 5 | 5 | 1600 ppm EPA RBC 100 ppm ATSDR chronic oral RMEG pica child 3000 ppm ATSDR chronic oral RMEG child 40,000 ppm ATSDR chronic oral RMEG adult |
| Platinum | 69-87 | 3 | 5 | No comparison values are available |
| Selenium | 150-620 | 5 | 5 | 390 ppm EPA RBC 10 ppm ATSDR chronic oral EMEG/RMEG pica child 300 ppm ATSDR chronic oral EMEG/RMEG child 4000 ppm ATSDR chronic oral EMEG/RMEG adult |
| Sodium | 27-33 ppm | 2 | 5 | No comparison values are available |
| Thallium | 69-79 ppm | 2 | 5 | 5.5 EPA RBC |
| Vanadium | 14-64 ppm | 5 | 5 | 550 EPA RBC 6 ppm ATSDR interim oral EMEG pica child 200 ppm ATSDR interim oral EMEG child 2000 ppm ATSDR interim oral EMEG adult |
| Zirconium | .85-2.9 ppm | 5 | 5 | No comparison values are available |
APPENDIX F: WATER ENVIRONMENTAL SAMPLING RESULTS AND ATSDR COMPARISON VALUES
Figure 1. Georgia Department of Natural Resources Monitoring Well Locations
in the Newtown Area
Figure 2. University of Georgia Soil Boring and Monitoring Well Location Map
Figure 3. Stormwater Runoff Sample Locations Collected by the City of Gainsville
Explanation of Comparison Values
Comparison Values (CVs)
The conclusion that a contaminant exceeds the comparison value does
not mean that it will cause adverse health effects. Comparison values represent
media-specific contaminant concentrations that are used to select contaminants
for further evaluation to determine the possibility of adverse public health
effects.
Cancer Risk Evaluation Guides (CREGs)
CREGs are estimated contaminant concentrations that would be expected
to cause no more than one excess cancer in a million (10-6) persons exposed
over lifetime. ATSDR's CREGs are calculated from EPA's cancer potency factors.
Environmental Media Evaluation Guides (EMEGs)
EMEGs are based on ATSDR minimal risk levels (MRLs) and factors in
body weight and ingestion rates. An EMEG is an estimate of daily human exposure
to a chemical that is likely to be without noncarcinogenic health effects over
a specified duration of exposure.
Reference Media Evaluation Guides (RMEGs)
ATSDR derives RMEGs from EPA's oral reference doses. The RMEG represents
the concentration in water or soil at which daily human exposure is unlikely
to result in adverse noncarcinogenic effects.
Risk Based Concentrations
Risk-Based Concentrations (RBCs) are the estimated contaminant concentrations
in which no chance exists for carcinogenic or non carcinogenic health effects.
The RBCs used in this public health assessment were derived using provisional
reference doses or cancer slope factors calculated by toxicologists of EPA's
Region III.
Table 1. Monitoring Well Sampling Conducted by Georgia Department of Natural Resources (1993)
|
Contaminants of Concern, 1993 Groundwater Monitoring
|
||||
| Contaminant | Range of detection levels (ppb)* | Frequency of detection | Total number of samples | Comparison value |
| Iron | 2300-34,000 | 2 | 2 | 11,000 ppb (drinking water level) EPA RBC |
Table 2. Monitoring Well Sampling Conducted by University
of Georgia (1994)
|
Contaminants of Concern, 1994 UGA Groundwater Monitoring
|
||||
| Contaminant | Range of detection levels (ppb)* | Frequency of detection | Total number of samples | Comparison value |
| Chlorine | 8800-22,800 | 2 | 4 | 1000 ppb ATSDR chronic RMEG child 4000 ppb ATSDR chronic RMEG adult |
| Iron | <50-94 | 4 | 4 | 11,000 ppb EPA RBC |
| Magnesium | 7400-9200 | 4 | 4 | No comparison value available |
| Silicon | 1400-1800 | 2 | 4 | No comparison value available |
| Sodium (salt) | 11,700-19,400 | 4 | 4 | No comparison value available |
Table 3. Stormwater Runoff Analysis Conducted by the City
of Gainesville Public Utilities Department 1994.
|
Newtown Stormwater Runoff Analysis 1994 (measured
in mg/L and µg/L)*
|
||||||
| Constituent | Newtown Sample |
Georgia In-State Criteria | NURP Study | Atlanta Regional Stormwater Study Means | ||
| Median Concentration | Residential | Commercial | Industrial | |||
| BOD (mg/l) | 22 | -- | 9 | 15 | <12 | <16 |
| T. Suspended Solids (mg/l) | 117 | -- | 100 | 574 | 103 | 97 |
| TKN (mg/l as N) | 2.7 | -- | 1.50 | <1.35 | <2.57 | <1.63 |
| NH3 (mg/l as in N) | 0.02 | -- | <0.22 | <0.51 | <0.41 | |
| Fecal Coliform (per 100/ml) | 178,000 | 200 geo. mean 4000 single sample |
21,000 | 7653 | 2460 | 3436 |
| T. Phosphorous (mg/l P) | 0.63 | -- | 0.33 | <0.44 | <0.18 | <0.36 |
| Oil & Grease (mg/l) | 10 | -- | -- | <4.9 | <16.4 | <6.3 |
| T. Copper (Cu) ug/l (EPA 220.2) | 12 | 6.5 | 34 | <53.4 | <20.3 | <22.6 |
| T. Chromium (Cr) ug/L (EPA 218.2) | 3 | 11 | -- | -- | -- | -- |
| T. Lead (Pb) ug/L (EPA 239.2) | 21 | 1.3 | 144 | <35.7 | <24.3 | <24.3 |
| T. Zinc (Zn) ug/l (EPA 200.7) | 180 | 60 | 160 | 115.6 | 132.3 | 194.9 |
Table 4. Tap Water Analysis of Seven Newtown Homes, 2000
|
Newtown Tap Water Lead Analysis- City of Gainesville
2000 (µg/L)*
|
||
| Newtown Levels | EPA Risk Based Concentration Level | Does Newtown level exceed the EPA comparison value? |
| 2.0 | 15 | no |
| 5.6 | 15 | no |
| 3.9 | 15 | no |
| 8.1 | 15 | no |
| 7.2 | 15 | no |
| <.002 | 15 | no |
| 3.8 | 15 | no |
APPENDIX G: CANCER RISK EVALUATION FOR BENZENE
Air emissions concentrations were collected by the Georgia Air Protection Branch and the exposure investigation conducted by ATSDR. Benzene was chosen for evaluation because a spike was detected in a single air cannister sample, and benzene was the only contaminant detected that exceeded ATSDR CVs in residential air within the boundaries of the Newtown community. Other contaminants were detected at the Fair Street School monitor above comparison values, however, whether those levels are indicative of residential air conditions is unknown. The location of that monitor is under investigation. The spike of benzene was also elevated much higher than any other contaminant that exceeded comparison values. Benzene ranges from 2.8 to 20 ppb in background levels of air, and is a common contaminant in industrialized areas. The spike of benzene was detected on the perimeter of a Gainesville facility, approximately .55 miles from the Newtown Community. The levels of benzene detected in residential air were usually at or slightly above ATSDR's CV for the Cancer Risk Evaluation Guide (CREG). This is a very conservative level at which ATSDR believes is safe for exposure. Initial screening with CREGs are based on continuous air exposure for a lifetime (estimated at 70 years). Cancer risk evaluation involves a more realistic exposure scenario using site-specific conditions, if known. Assumptions used in the risk assessment of benzene air emissions are as follows:
The following table presents the results of the risk analysis. The level of benzene measured in each area of Newtown is presented in parts per billion (ppb), compared to a cancer comparison value (ATSDR CREG), the number of samples represented in each area are identified, and the results of the cancer risk evaluation are presented as a potential increase in cancer of 1 case per 100,000 people. These results indicate that all levels detected within residential areas indicate no apparent increase in cancer risk. The highest level, a spike detected at the perimeter of an area facility, over a half a mile from the community, indicated a low increased risk for cancer. This would be true only if benzene was consistently present at this elevated concentration, which is highly unlikely given that it was the only sample detected above 2.6 ppb. In conclusion, exposure to benzene air emissions is unlikely to result in increased cancer risk in the Newtown Community.
|
Benzene Cancer Risk Evaluation for Lowest to Highest Level Detected | |||
|
Area |
Range of Levels Detected (ppb) | ATSDR CREG (ppb) |
Estimated Increase in Excess Cancer Risk |
|
Newtown and Surrounding Area |
.65-23 |
.1 | 1.6E-05 to 5.8E-04 (1.6/100,000-5.8/10,000) |
|
Risk Category Definitions Used by ATSDR | |||
| Category | Fraction | Decimal | Exponential |
| No Increased Risk | <1/100,000 | <0.00001 | <1E-05 |
| No Apparent Increased Risk | 1/100,000 | 0.00001 | 1E-05 |
| Low Increased Risk | 1/10,000 | 0.0001 | 1E-04 |
| Moderate Increased Risk | 1/1,000 | 0.001 | 1E-03 |
| High Increased Risk | 1/100 | 0.01 | 1E-02 |
| Very High Increased Risk | >1/100 | >0.01 | >1E-02 |
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