PETITIONED PUBLIC HEALTH ASSESSMENT ADDENDUM
SOUTHERN WOOD PIEDMONT
AUGUSTA, RICHMOND COUNTY, GEORGIA
PETITIONED HEALTH ASSESSMENT
SOUTHERN WOOD PIEDMONT
AUGUSTA, RICHMOND COUNTY, GEORGIA
The Southern Wood Piedmont (SWP) site is located in Augusta, Georgia. Wood-treating operations were conducted at the site from 1923 until 1988. Closure operations at the facility were regulated under the Resource Conservation and Recovery Act (RCRA). When the facility was operating, wastewaters containing hazardous substances were discharged to an on-site, unlined surface impoundment and to off-site drainage ditches. These disposal practices resulted in contamination of groundwater with high concentrations of wood treatment chemicals including arsenic, pentachlorophenol, and polyaromatic hydrocarbons (PAHs). Private wells in residential neighborhoods located north and east of the facility have been contaminated with high concentrations of naphthalene and other PAHs. Although some residents were probably exposed to site-related contaminants through domestic potable water use, the health impact of these past exposures cannot be determined. The Richmond County water utility extended municipal water lines to residents with contaminated wells in 1976 and in 1989. Currently, all of the homes in the affected neighborhoods are reportedly connected to the public water system. Soil samples from residential lots north of the site and dust samples from attics of homes did not contain concentrations of inorganic contaminants that pose a public health hazard. Sediment samples from drainage ditches along the eastern border of the SWP facility were contaminated with site-related chemicals. The results of recent air monitoring studies did not indicate the presence of site-related contaminants at levels of significant health concern. There are insufficient air monitoring data from the period when the facility was operating to assess the health significance of past air exposures. Epidemiologic studies conducted at the site do not conclusively prove or disprove the presence of an increased incidence of disease or disease symptoms among residents living near the site.
The SWP site is categorized as an indeterminate public health hazard. Past exposures to on-site and off-site contamination may have exceeded current dose levels. However, the available information is not sufficient to assess the potential health impact of past exposures to site contaminants. Recent studies have demonstrated the presence of site-related chemicals in sediment from off-site drainage ditches. The health impact of contact with the contaminated sediment would depend on the frequency and length of exposure.
ATSDR has recommended to the U.S. Environmental Protection Agency (EPA) and the Georgia Environmental Protection Division (EPD) that the following actions be taken: restrict public access to the site; post warning signs around the perimeter of the site; remove from service private wells affected by contamination from SWP; conduct additional monitoring in soil and in ditch sediments east of the site to further characterize contamination; and conduct air monitoring during removal and remedial operations at the site. These actions have already been conducted under the regulatory authority of the EPA and EPD. In addition, EPA has indicated that further monitoring will be conducted at off-site locations to define the extent of soil and sediment contamination.
Based on its evaluation of the data and recommendations from the Agency for Toxic Substances and Disease Registry (ATSDR) Health Activities Recommendation Panel, ATSDR will conduct the following public health actions at the SWP site:
- a community health investigation to evaluate health concerns of the community living near the site and to assess whether those concerns are related to exposure to hazardous substances;
- a dose reconstruction investigation to assist in determining potentially exposed populations; and
- community health education to assist community members in understanding their potential for exposure to hazardous substances in the environment.
In addition, ATSDR held two public availability meetings on January 11, 1992 (one at Butler High School and one at Clara Jenkins Elementary School). ATSDR staff met with citizens one-on-one and in small groups to discuss the Public Health Action Plan and to gather community input.
ATSDR is authorized to perform health assessments for releases or facilities where individuals or licensed physicians provide information that people have been exposed to a hazardous substance. On February 15, 1988, ATSDR received a petition regarding the Southern Wood Piedmont facility. This health assessment responds to that petition.
A. SITE DESCRIPTION AND HISTORY
The Southern Wood Piedmont (SWP) wood treatment facility is located at 1650 Nixon Road in Augusta, Georgia (see map - Appendix I). The 78-acre site has been used for wood preserving activities dating back to the 1920s, although ownership has changed several times. An estimated 28 acres were used for wood preserving activities. The remainder of the 78 acres was either undeveloped wooded area or was used for preprocessing activities. The facility operated as Southern Wood Piedmont from 1971 until it closed in 1988. Cleanup and closure operations at the facility are regulated by the Resource Conservation and Recovery Act (RCRA).
Wood treatment preservatives used at the facility were creosote, pentachlorophenol (PCP), chromated copper arsenate (CCA), and zinc meta-arsenate (ZMA). SWP reported that the following wood treatment preservatives were used during the indicated dates:
|Creosote||1927 - 1984|
|PCP||Mid 1960s - 1988|
|CCA||1981 - 1988|
|ZMA||Mid 1930s - Mid 1940s|
During the operating life of the facility, plant wastewaters were handled in various ways. From approximately 1927 to 1973, plant effluent was processed through an oil/water settling separation and recovery system. The process water was then discharged to drainage ditches.
In 1973, an unlined surface impoundment was constructed to act as a biological treatment unit to process wastewater containing wood preserving constituents. Processed wastewater was then discharged to the municipal sewer system under an approved permit.
In 1986, the surface impoundment was closed under terms of a closure plan approved by the Georgia Department of Natural Resources. Wastewater was then processed in an on-site wastewater treatment facility. After treatment, process water containing wood preserving constituents was discharged to the municipal sewer system.
After closing the wastewater impoundment, the remaining sludge was removed and shipped off-site to an approved hazardous waste disposal facility. Closure of the impoundment was executed under RCRA regulations using a closure plan approved by the State of Georgia and reviewed by the U.S. Environmental Protection Agency. A RCRA post-closure care permit was signed on March 22, 1989.
Previous ATSDR activity at the SWP site included a health consultation, which was released on February 13, 1987 (1). This consultation was prepared in response to a request from the Division of Epidemiology, Georgia Department of Human Resources.
B. SITE VISIT
Representatives of the ATSDR headquarters and regional office visited the site and met with the petitioners on December 18, 1989.
The site has undergone extensive remediation, and clean-up operations were continuing at the time of the site visit. Most of the buildings, tanks, equipment, rail lines, and storage sheds have been removed from the site.
The terrain of the facility grounds and surrounding area is flat. The site was fenced except for a short open section along the back side (southwestern border) of the facility. At the time of the site visit, large mounds of black-colored dirt were piled at the rear of the site. Some of the mounds were covered with plastic sheets. Groundwater extraction sumps were observed at the northeastern corner and southern border of the facility. At the northeastern corner of the facility, plastic pipes crossed the site and discharged into a sewer manhole along Nixon Road. No liquids were being discharged at the time of the site visit, but a creosote odor was noted in the manhole.
A residential neighborhood consisting primarily of small, older homes is located north of the facility along Nixon Road. SWP purchased several property lots along Nixon and Winter Roads and demolished the buildings. Monitoring wells have been installed on some of these lots, which are now vacant. A small waste oil storage facility is located on Winter Road. There is also a large manufacturing facility (Thermal Ceramics, Inc.) located about 2,000 feet north of SWP.
The land south of SWP is vacant except for a warehouse located at the southwestern corner. This land is covered with heavy brush and trees. SWP recently graded the area outside of its southern border to remove the remaining debris. However, numerous pieces of wood were noted at the surface, and a creosote odor and sheen were noticed on rain puddles in the area.
Railroad tracks (Georgia/Florida Railway) border the western edge of the facility. On the opposite side of the tracks from SWP is a residential neighborhood. Railroad tracks (Central of Georgia Railroad) also run parallel to and within a few hundred feet of the eastern border of the facility.
C. COMMUNITY HEALTH CONCERNS
Residents living in neighborhoods near the SWP facility have reported numerous health problems. Medical conditions and illnesses reported include cancer (colon, skin, brain, lung, kidney, bladder, liver, leukemia, Hodgkins disease), kidney and bladder disease, skin lesions, allergies, sinus problems, and headaches. The residents expressed concern that these problems might be related to past or current exposures to contaminants from the site.
Citizens were concerned that chemicals from the site could contaminate fruit (peaches, pears) grown in the area or fish caught in nearby bodies of water (ponds, Rocky Creek). There have been reports that contact with soil in off-site drainage ditches resulted in skin irritation and lesions.
A class action suit has been filed against SWP on behalf of the residents. Specific illnesses that were attributed to exposures from the site included dermal keratosis, chronic conjunctivitis, and cancer (skin, leukemia).
D. STATE AND LOCAL HEALTH DATA
The plaintiffs' attorneys hired a consultant (Richard Bird) to conduct a health study of 58 residents who lived in the area adjacent to the SWP facility. The study, conducted in August 1987, consisted of a door-to-door survey of self-reported health symptoms and illnesses. The author of the study concluded that there were "significantly higher symptom and illness prevalence rates reported by residents living near the plant when compared to a control neighborhood." (2)
The Georgia Department of Human Resources reviewed death certificates from Richmond County to determine if there were increased incidences of nine types of cancer (bladder, Hodgkins, leukemia, liver, lymphoma, nasopharynx, scrotum/testicular, or soft tissue) in residents living near the site during the period from 1979 to 1986 (3). The results of this study and the Bird study are discussed in the Public Health Implications section of this petitioned Health Assessment.
The land surrounding the SWP facility is used for both residential and commercial purposes. Residential neighborhoods are located directly north and west of the facility, as well as further to the east. The land to the south and southeast is largely undeveloped.
The alluvial surficial aquifer beneath the site is not used for potable water. The Cretaceous-age Gaillard Formation (the Lower Sand Aquifer) is used for potable water. This aquifer is separated from the surficial aquifer by a thin, silty, clay aquitard which pinches out east of the site.
The Thermal Ceramics, Inc. facility is located about 2,000 feet north of the site. A cone of depression is formed in the potentiometric surface of the lower sand aquifer beneath the facility when the two on-site industrial water wells are pumped. The cone of depression from these wells does not extend beneath the Southern Wood Piedmont site, based on ground water elevation measurements in the Lower Sand Aquifer conducted on January 8, 1986, by consultants for Southern Wood Piedmont. However, a pumping test conducted by Geotrans, Inc. in April 1989 indicated that pumping in nearby water production wells could result in the formation of a cone of depression extending beneath the Southern Wood Piedmont facility.
Before the mid-1970s, residents in the area relied on private wells for potable water. In 1976, water lines from the Richmond County public water system were extended into the neighborhood north of the site. It is believed that all homes in the area are currently connected to the County water system (4), and remaining wells are not being used for either potable or nonpotable purposes (5).
In January 1989, elevated concentrations of PAHs were detected in private wells on Old Gravel Pit Road, which is located about 3,000 feet east of SWP. Public water lines have since been extended into this area.
A. ON-SITE CONTAMINATION
Analyses of groundwater samples from on-site monitoring wells indicated the presence of high concentrations of chemicals used in wood treatment operations.
|Phenanthrene + anthracene||2220|
|Chrysene + benzo(a)anthracene||43|
|Benzo(b)fluoranthene + Benzo(k)fluoranthene||12|
|m-Cresol + p-cresol||27|
The data in Table 1 were obtained in 1987 for the on-site monitoring well, MW-1C (6). This well, which is screened in the recent alluvium aquifer, was the most highly contaminated on-site well. Contaminant concentrations in the lower sand aquifer (monitoring wells 1B and 1C) were substantially lower.
Pentachlorophenol (PCP) was extensively used at the site and was found in on-site groundwater and soil samples. Commercial grades of PCP are often contaminated with chlorinated dibenzodioxins (CDDs) and chlorinated dibenzofurans (CDFs) (7). Furthermore, it has been suggested that lower chlorinated CDDs and CDFs (especially 2,3,7,8-substituted isomers) may be formed by the catalytic dechlorination/hydrogenation of hepta and octa CDDs/CDFs in metal containers during pressure treatment of wood with pentachlorophenol (8). As indicated in Table 2, several congeners of higher chlorinated CDDs and CDFs were detected in on-site environmental media at the SWP facility.
|CHEMICAL||CONCENTRATION (mg/kg) (*)|
|(*) Maximum on-site soil concentration detected in a 1977 industrial hygiene survey (9). The soil sample was collected at the mixing and silo area.|
|CHEMICAL||CONCENTRATION (ug/L) (**)|
|(**) Maximum concentration detected in on-site groundwater. The samples were collected on January 30, 1987 during a study conducted by the Environmental Services Division, Environmental Protection Agency (EPA) - Region IV (10).
(J) Estimated concentration
In April 1990, a contractor for SWP conducted on-site and off-site air monitoring while remedial activities (involving soil excavation) were in progress (11). The on-site air monitoring stations were located at the periphery of the facility, and the off-site air monitoring stations were located across from the facility, north of Nixon Road. In this study, air particulates were collected and analyzed for site-related contaminants, including CDDs and CDFs. Low concentrations of CDDs and CDFs were detected in on-site and off-site air particulate samples. For risk assessment purposes, the toxicity of CDD and CDF mixtures is sometimes expressed as an equivalent dose of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), which is the most toxic congener of the series (12). Using the EPA's Toxicity Equivalence Factor (TEF) approach (12), it was reported that the air concentrations of 2,3,7,8-TCDD equivalents ranged from 0.0074 to 0.0899 pg/m3. In these calculations, the TCDD equivalents were calculated by multiplying the measured congener concentration (or the detection limit concentration if none was detected) by the appropriate TEF.
B. OFF-SITE CONTAMINATION
The extent of off-site groundwater contamination in the Lower Sand Aquifer has been determined by collecting and analyzing ground water samples from monitoring wells and residential drinking water wells. Evidence of contamination of private wells with site-related chemicals is presented in Table 3. In one sampling event conducted by the U.S. Environmental Protection Agency - Region IV in 1989, trichloroethylene was detected in two private wells located on New Savannah Road at concentrations of 380 ug/L and 180 ug/L. Table 4 presents data from the analyses of samples of soil, sediment from drainage ditches, and dust from the attics of homes in the area.
(Lower Sand Aquifer)
|Nixon/Winter Road (a)||Old Gravel Pit Road (b)|
|ND = Not Detected
NR = Not Reported
(a) On June 9, 1988, Olfacto-Labs sampled four private wells located north of SWP (13). Two of the wells were on Nixon Road, and two were on Winter Road. These data show the maximum concentrations of contaminants detected in water samples from the four wells. At the time of the sampling, the wells were not being used for potable purposes.
(b) On January 26, 1989, the Georgia Department of Environmental Resources collected water samples from private wells on Gravel Pit Road. These data are for the most highly contaminated well.
|SEDIMENT (a)||SEDIMENT (b)||SOIL (c)||Dust (d)|
|* phenanthrene + anthracene
(a) Maximum concentration of contaminant detected in sediment samples collected from drainage ditches located along the northern or eastern border of the SWP facility (14). The samples were collected by the Georgia Department of Natural Resources on December 10, 1985. The facility was operating at the time the samples were collected.
(b) Soil samples collected from drainage ditches from residential areas north of Nixon Road. Samples were collected by Law Environmental Services on June 10, 1986 (15). The maximum concentration detected in six samples is reported.
(c) Maximum concentration of contaminant detected in surface soil samples (0-2 inches) collected from two lots located on Nixon Road across from SWP. The samples were collected November 7, 1988 (16).
(d) Dust samples collected from the attics of four private homes near the SWP facility. Samples were collected on November 11, 1988, by McCrone Associates. The maximum concentration of contamination that was detected in the four samples is reported.
Recently, two additional analytical studies of on- and off-site soil and sediment have been conducted. On June 28-29, 1990, employees of Geraghty & Miller, Inc., consultants for SWP, collected 23 surface and subsurface soil or sediment samples from on-site and off-site locations (17). Sampling locations included the drainage ditches along the eastern boundary of the SWP property and along the Central of Georgia Railroad tracks. Analyses of these samples revealed the presence of CDDs and CDFs. The contaminant concentrations in sample SD-2, which was the most highly contaminated sample, are shown in Table 5. Sample SD-2 was collected from the north-south drainage ditch along the eastern border of SWP.
A second study of off-site soil/sediment was conducted by the U.S. Environmental Protection Agency - Region IV on September 26-27, 1990 (18). In this study, 13 soil or sediment samples were collected from ditches and other locations near the SWP facility and analyzed for CDDs and CDFs. The most highly contaminated sample, SWP-07-S, was collected from a drainage ditch east of the SWP facility along the Central of Georgia Railroad tracks. The analytical results for this sample are shown in Table 5.
|2,3,7,8 Tetrachlorodibenzodioxin||0000.014||000.023 J|
|Tetrachlorodibenzodioxin (total)||0000.26||000.032 J|
|Pentachlorodibenzodioxin (total)||0001.3||000.510 J|
|1,2,3,6,7,8 Hexachlorodibenzodioxin||0000.34||003.1 J|
|1,2,3,7,8,9 Hexachlorodibenzodioxin||0000.85||001.5 J|
|Hexachlorodibenzodioxin (total)||0016||051 J|
|1,2,3,4,6,7,8 Heptachlorodibenzodioxin||0230||046 J|
|Heptachlorodibenzodioxin (total)||0530||130 J|
|Octachlorodibenzodioxin (total)||2000||320 J|
|Pentachlorodibenzofuran (total)||0000.82||000.046 J|
|Hexachlorodibenzofuran (total)||0014||007.1 J|
|1,2,3,4,6,7,8 Heptachlorodibenzofuran||ND||015 J|
|1,2,3,4,7,8,9 Heptachlorodibenzofuran||0002.5||001.3 J|
|Heptachlorodibenzofuran (total)||0098||041 J|
|Octacholordibenzofuran (total)||0450||220 J|
|J - estimated value
R - Quality Control indicates that data are unusable; compound may or may not be present
ND - not detected
(a) Off-site composite sediment sample SD-2. Collected from drainage ditch along eastern boundary of SWP facility on June 28, 1990 (17).
(b) Off-site soil sample SWP-07-S. Collected from drainage ditch along Central of Georgia Railroad tracks on September 27, 1990 (18).
C. QUALITY ASSURANCE AND QUALITY CONTROL
In preparing this Petitioned Health Assessment, ATSDR relies on the information provided in the referenced documents and assumes that adequate quality assurance and quality control measures were followed with regard to chain-of-custody, laboratory procedures, and data reporting. The validity of the analyses and conclusions drawn for this Petitioned Health Assessment is determined by the availability and reliability of the referenced information.
D. PHYSICAL AND OTHER HAZARDS
The facility is no longer operating and is fenced. The waste impoundment has been closed, and many of the structures and equipment on the site have been removed. No imminent physical hazards were observed at the site.
A completed exposure pathway consists of a source of contamination, a medium for contaminant migration in the environment, a point of human exposure, a route of contaminant entry into the human body, and a receptor population. Four exposure pathways have been evaluated by ATSDR: migration of contaminants in groundwater to drinking water wells, migration of contaminants in surface water drainage ditches to aquifers and then to water wells, migration of contaminants in air to residential areas, and bioaccumulation of contaminants in fish and edible plants in the vicinity of the Southern Wood Piedmont site. Following are analyses for each of these exposure pathways.
A. GROUNDWATER CONTAMINATION
- Sources of Contamination: The source of arsenic in groundwater may have been the old zinc meta-arsenate tank. Creosote operations on-site were the source of PAHs in groundwater. Tetrachloroethylene was detected in on-site groundwater (19), but the specific on-site source of tetrachloroethylene is not known.
- Environmental Media: Wood-treating chemicals were discharged to surface water drainage
ditches and subsequently percolated into ground water in the Lower Sand Aquifer (also known as
the Gaillard Formation).
Naphthalene was detected throughout most of the plume of contaminated groundwater, and it may be the most conservative (i.e. least attenuated) PAH contaminant in the plume. Therefore, naphthalene may be used as a tracer to estimate the rate and extent of contaminant migration in groundwater. ATSDR used naphthalene concentrations in groundwater monitoring results and solute transport parameters reported by Law Environmental Services, Inc. to analyze naphthalene transport and dispersion in the Lower Sand Aquifer. The results of these analyses indicate that naphthalene could migrate from contaminated ditches through the aquitard overlying the Lower Sand Aquifer, and enter the aquifer in one to five years. Naphthalene has been slowly advected (carried in a dissolved state with groundwater) and dispersed beyond points where it percolated into the Lower Sand Aquifer at a rate of about 8 feet per year. Wood-treating chemicals in the Lower Sand Aquifer remain within a few hundred feet of the overlying contaminated drainage ditches. The contaminated ditches extended at least as far as Hole #2 (2,400 feet southeast of the site) and may have extended to a groundwater discharge zone in Phinizy swamp, located about 4,000 feet east of the site. Groundwater contamination may have occurred within this area as a result of the migration of contaminants from the ditches to interconnected aquifers.
Non-aqueous phase liquid (NAPL) wood-treating contaminants were detected in the unconfined aquifer on-site. NAPLs were not detected off-site or in the semi-confined aquifer.
In addition to the wood-treating chemicals described previously, trichloroethene (TCE) was detected in two water wells along New Savannah Road at concentrations of 380 ug/L and 180 ug/L. The source of the TCE has not been identified. However, on July 8, 1989, the EPA issued an Administrative Order stating that off-site wells were contaminated with high concentrations of TCE as well as various extractable organics including phenanthrene, naphthalene, and dibenzofuran; that tetrachloroethylene was reported as a constituent appearing in a monitoring well on the RCRA site under "Appendix 9" sampling and reporting requirements of RCRA; and that tetrachloroethylene degrades in the environment into a number of other contaminants, including but not limited to TCE. EPA concluded that SWP caused or contributed to the endangerment of the underground source of drinking water (19).
- Points of Exposure: Groundwater monitoring results indicate that human exposure to
hazardous substances occurred at the following locations: water wells along Nixon Road from
Doughty Street to Winter Road; water wells along New Savannah Road from Nixon Road to a
point about 1,400 feet south of the intersection of Nixon and New Savannah Roads; and water
wells at residential areas along Gravel Pit Road.
Naphthalene may have migrated in the Lower Sand Aquifer to points of human exposure along Nixon and Winter Roads within 11 to 25 years after contaminants were discharged into ditches along these roads (about 1934 to 1948). Water wells along New Savannah Road are farther from the ditches than wells along Nixon and Winter Roads, and naphthalene may not have reached these water wells until about 61 to 66 years after contaminants were discharged into ditches (about 1984 to 1989). The dates when contamination of the residential area along Gravel Pit Road may have occurred cannot be estimated, because subsurface drainage pathways have not been located. The surface water drainage ditch apparently becomes a subsurface drainage path at the sampling location designated as "Hole #2" in reports prepared by Law Environmental Services, Inc.
- Routes of Human Exposure: Contaminants could have affected the human body via ingestion, inhalation, dermal contact, and dermal absorption.
- Receptor Population: Humans exposed to hazardous chemicals include residents consuming
drinking water or using water for other household purposes from off-site contaminated wells as
noted previously; and Southern Wood Piedmont employees who consumed contaminated water
from on-site drinking water wells.
The presence of PAHs in drinking water wells presented a completed exposure pathway in the past for Southern Wood Piedmont employees and residents. Municipal water lines were extended into contaminated areas in 1976 and in 1989 (4). There are no known current human exposures to contaminated groundwater.
B. SURFACE WATER AND SEDIMENT CONTAMINATION
- Source of Contamination: Wastewaters containing heavy metals, PAHs, and
pentachlorophenol were discharged to drainage ditches along the periphery of the Southern Wood
Piedmont property. Creosote discharges probably occurred from 1927 to the late 1960s. Zinc
meta-arsenate discharges probably occurred from the mid 1930s until zinc meta-arsenate use was
discontinued in the mid 1940s. No information was available regarding when discharges of
pentachlorophenol and chromated copper arsenate began, but Southern Wood Piedmont stated
that ditch discharges were discontinued in the late 1960s. Approximately 50,000 gallons of
pentachlorophenol were spilled on the site in 1973. The pentachlorophenol was contained at the
northeastern property boundary by damming a ditch.
When the plant was operating, before the late 1960s, wastewaters were discharged to drainage ditches that paralleled the northern and eastern borders of the facility. During periods of heavy rainfall, surface water runoff from the facility could also flow off-site into the drainage ditches. It is possible that wastewaters that were discharged to these ditches contained high concentrations of wood treatment chemicals. Environmental officials reported that oil sheens and phenolic odors were detected in these ditches when the plant was operating (14). However, there are no historical data to document water contaminant concentrations in these waste streams. Therefore, it is not possible to assess the potential health impact on individuals who may have come into contact with these wastewater streams.
- Environmental Media: Sediments in off-site ditches along the periphery of the facility were contaminated with wood treatment chemicals. No surface water bodies used for drinking water supplies were contaminated by discharges to the ditches.
- Points of Human Exposure: Sediment samples were collected from drainage ditches along
streets north and east of the site, from a ditch along the cross-country power line, and from a
ditch leading southeast from the cross-country power line.
Concentrations of heavy metals, PAHs, and pentachlorophenol were compared to background samples to locate points of potential human exposure to contaminants from the site. Background samples were collected by Law Environmental Services and by the Richmond County Commission at the Hyde Park Recreation Center, located about 4,000 feet north of the site. Low concentrations of heavy metals are naturally present in soils. Therefore, ATSDR used 95% confidence intervals for concentrations of heavy metals detected in background samples to estimate the range of natural background values. A 95% confidence interval is a statistically calculated range of expected values, such that there is a 95% chance that the true value will lie within the range, based on a normal distribution.
The results of the sediment analyses indicated that copper, chromium, lead, mercury, nickel, and zinc were present above background levels in sediments along Nixon Road (15, 20). All of these heavy metals, including arsenic, were present above background levels in ditch sediments along Winter Road. Arsenic, chromium, zinc, and PAHs were present above background levels in the cross-country power line ditch. Arsenic and PAHs were present above background levels in the ditch leading southeast from the cross-country power line ditch. An isolated portion of a ditch along the south side of Doughty Street, about 700 feet northeast of the intersection with Nixon Road, also contained PAHs and arsenic above background levels.
Several soil samples were collected in areas beyond the drainage ditches. Results from these samples indicate that contamination is primarily restricted to the ditches.
Studies conducted in June 1990 and September 1990 demonstrated the presence of low concentrations of CDDs and CDFs in soil/sediment from the drainage ditches located east of the SWP facility. These data are presented in Table 5.
- Routes of Human Exposure: Contact with sediment in the drainage ditches could result in dermal exposures to chemical contaminants and possibly the ingestion of small quantities of sediment. The reported concentrations of contaminants in the ditches north of SWP would not be expected to pose a significant health hazard. Elevated concentrations of site-related contaminants, including CDDs and CDFs, were detected in drainage ditches located east of the SWP facility. The potential health impact of exposure to soil and sediment in these ditches would depend on the frequency and length of exposure.
- Receptor Population: The potential receptor populations include former employees of Southern Wood Piedmont and residents of the neighborhoods surrounding the facility. Neighborhood children who play in the drainage ditches are a population of particular concern.
C. AIR CONTAMINATION
- Sources of Contamination: Heavy metals and organic compounds from wood-treating operations at the Southern Wood Piedmont facility may have been present in air on-site and off-site.
- Environmental Media: In February 1988, when the plant was operating, air monitoring for
pentachlorophenol was conducted at several locations on the plant site and along the northeastern
plant boundary, adjacent to residential areas along Nixon Road. A 24-hour sample was collected.
Pentachlorophenol was detected at a maximum concentration of 2.312 micrograms per cubic
meter at a point 355 feet northeast (downwind) from the treatment cylinders and tank farm (21).
During remedial activities in 1990, air particulates were collected at on-site and off-site air monitoring stations. Analyses of the samples revealed low concentrations of CDDs and CDFs (Table 2), but no detectable pentachlorophenol (11).
ATSDR evaluated the potential for migration of contaminated dust from ditches surrounding the site to neighborhoods using EPA methods for assessing particulate emissions from contaminated soils (22) and meteorological data for Augusta provided by the State. The results of the analysis indicated that fine-grained portions of soils on the site are moderately susceptible to erosion by wind.
- Points of Human Exposure: Human exposure to air contaminants would be greatest on the
Southern Wood Piedmont site. Off-site points of exposure to air contaminants might include
commercial and residential areas along a 280-degree arc extending clockwise from the
west-southwestern boundary of the site toward the north, then toward the southeast.
In 1988, dust samples were collected from the attics of four houses on Winter Road and analyzed for heavy metals. Analyses of undisturbed dust samples might give a cumulative indication of past contaminant levels in airborne particulates. As indicated in Table 4, attic dust samples did not contain heavy metal concentrations of health concern.
- Routes of Human Exposure: Inhalation of contaminated dusts and volatile compounds is the major route of human exposure to air contaminants. To a lesser extent, skin contact with some air contaminants (e.g., pentachlorophenol, PAHs) could result in dermal absorption.
- Receptor Population: The receptor population would have included employees of Southern
Wood Piedmont, and other businesses in the area, and residents in surrounding neighborhoods.
Air sampling was conducted for one organic contaminant (pentachlorophenol) while the plant was
operating. Past concentrations of other site-related contaminants in on-site or off-site air beyond
the facility property are not known.
The current potential for exposure to air contaminants is greatest for on-site workers conducting remedial activities. On-site excavations might uncover pockets of wastes containing high concentrations of volatile and non-volatile contaminants. If adequate dust suppression procedures are not implemented during remedial operations, off-site migration of contaminated dusts is possible.
D. CONTAMINANTS IN THE FOOD CHAIN
- Source of Contamination: Wood-treating chemicals from the Southern Wood Piedmont plant were discharged into surface water drainage ditches.
- Environmental Media: Heavy metals and PAHs were detected above background levels in
several drainage ditches adjacent to residential areas. One of the contaminated ditches, the
cross-country power line ditch, discharges into Rocky Creek about 3,800 feet south of Nixon
Road. Rocky Creek discharges into Phinizy Swamp about 4,000 feet downstream of the
confluence with the power line ditch.
In 1985, water and sediment samples were collected from Rocky Creek at locations upstream and downstream of the power line ditch discharge point. The samples were analyzed for water quality parameters and for site-specific chemicals. There was no significant difference in upstream and downstream water quality as judged by the parameters measured. The Chemical Oxygen Demand (COD) of the downstream sediment sample was higher than the upstream sample, but increased concentrations of site-specific chemicals were not detected (14).
The contaminants detected in the drainage ditches were evaluated to determine whether bioaccumulation might occur in fish and other aquatic species if contaminants were discharged to Rocky Creek and Phinizy Swamp. Arsenic, chromium, and zinc do not significantly bioaccumulate in fish. In general, PAHs are readily metabolized in fish and do not significantly bioaccumulate. In shellfish, PAH metabolism is much slower, and bioaccumulation may occur. Pentachlorophenol, CDDs, and CDFs may be significantly bioaccumulated in fish.
Contaminants detected in drainage ditches were also evaluated to determine whether they might bioaccumulate in plants. Arsenic, chromium and lead are absorbed from soil by plants, but are not translocated within the plant beyond the roots (23). Copper, mercury, nickel and zinc are also absorbed from soil by plants, and may be translocated within the plant beyond the roots. Plants do not bioconcentrate PAHs from the soil. When plants are grown in PAH-containing soil, the PAH concentrations are generally higher on the plant surfaces (such as peelings of fruit) than in internal plant tissues (24).
No fish or plant tissue analyses were included in the reference materials reviewed by ATSDR.
- Points of Exposure: Fishing areas may exist in Phinizy Swamp in locations where contaminated
sediments, surface water, or groundwater discharged or are currently discharging.
The state expressed concern about whether contaminants from the site may accumulate in fruit trees in residential areas. Because sediment and soil contamination are primarily restricted to drainage ditches, and neither crops nor fruit trees are present in these ditches, there are no known points of human exposure to edible plants contaminated by the site.
- Routes of Human Exposure: Ingestion of contaminants that have bioaccumulated in fish or edible plants is a potential route of human exposure.
- Receptor Population: It is not known if fish or other aquatic species from Rocky Creek or
Phinizy Swamp are consumed by local residents. No site-specific chemicals were detected in
water samples from Rocky Creek. ATSDR can not unequivocally determine whether fish
consumption poses a public health hazard because edible fish from potentially affected surface
waters were not analyzed for contamination.
The National Academy of Sciences and the National Academy of Engineering have established recommended land treatment loading rates for heavy metals in soils. None of the soil samples beyond the site property or contaminated drainage ditches exceeded these recommended soil concentrations for heavy metals. High concentrations of PAHs and pentachlorophenol were also restricted to the SWP facility and contaminated ditches. Since food crops are not grown or harvested from these ditches, it is not likely that residents would be exposed to contaminants from the site via consumption of edible plants.
A. TOXICOLOGICAL IMPLICATIONS
Groundwater from private wells surrounding the site is contaminated with high concentrations of polynuclear aromatic hydrocarbons (PAHs). Currently, it is believed that all homes in the area surrounding the site have been connected to the Richmond County public water system. However, it is likely that some residents were exposed to contaminated groundwater before their homes were connected to the public water system. Furthermore, as recently as January 1989, PAH contamination was discovered in private wells being used by residents on Gravel Pit Road.
Water samples collected from private wells contained concentrations of naphthalene in excess of 2 mg/L and lower concentrations of other PAHs (Table 2). In humans, the oral ingestion of large doses of naphthalene can cause hemolytic anemia (25). It has also been reported that oral ingestion of naphthalene can cause liver toxicity as evidenced by elevated levels of liver enzymes and jaundice (25). However, quantitative data on the toxicity of naphthalene are very limited, and it cannot be unequivocally determined whether the water concentrations of naphthalene detected in private wells were high enough to cause adverse health effects.
Certain individuals may be especially sensitive to the hemolytic action of naphthalene, including infants and individuals deficient in the enzyme, glucose-6-phosphate dehydrogenase (G-6-PD). This enzyme deficiency occurs in about 10 percent of African-American men and fewer African-American females. It also occurs at a lower frequency in people from the Mediterranean basin (Italians, Greeks, Arabs, Sephardic Jews) (26). These individuals, in particular, should avoid exposure to naphthalene.
Other PAHs detected in water samples from the private wells included acenaphthene and fluorene (Table 2). Exposure to high doses of these chemicals can be toxic to the liver, blood, and other body organs (27). However, the concentrations of these PAHs detected in water samples from private wells would not be expected to cause such toxic effects. The available toxicity information on other PAHs detected in private well water samples (methylnaphthalene, dibenzofuran, phenanthrene) is insufficient to assess their potential health impact.
High concentrations of trichloroethylene (380 ug/L and 180 ug/L) were detected in water samples from two private wells along New Savannah Road. These TCE concentrations significantly exceed the Maximum Contaminant Level (5 ug/L) promulgated under the National Safe Drinking Water Act; therefore, these wells should not be used for either potable or nonpotable purposes.
Residents near the site have complained of numerous skin problems including hyperkeratosis, skin cancers, dermatitis, and psoriasis. It has been reported that ingestion of arsenic may cause hyperkeratosis of the palms and soles and hyperpigmentation around the eyelids, temple, neck, nipples, and groin (28). To a lesser extent, dermal effects have also been reported to result from inhalation and/or direct skin contact with arsenic compounds. Epidemiologic evidence also suggests that oral ingestion of arsenic may cause skin cancer (squamous cell carcinomas), and inhalation of arsenic compounds may cause lung cancer.
No ambient air monitoring data for arsenic were available. However, dust samples from attics of homes in the area did not contain elevated arsenic concentrations. Although these data suggest that there was not a significant release of arsenic-containing particulates from the site, this conclusion is limited by the small number of samples tested.
The available data do not indicate that residents living near the site have been exposed to environmental arsenic contamination at levels that would pose a public health hazard. However, this conclusion is limited by the availability of off-site arsenic contamination data.
Pentachlorophenol (PCP) was detected at a maximum concentration of 2.3 ug/m3 during ambient air monitoring conducted near the site in February 1988 (21). Very little information exists on the toxic effects of inhalation exposures to PCP in humans or laboratory animals. Ingestion of large doses of PCP by laboratory animals may be toxic to the liver and kidneys (29). However, the concentrations of PCP that were detected in ambient air samples near the site would not be expected to cause such toxicity in humans. Several case studies have reported that dermal contact with PCP may cause dermatitis and other skin conditions in humans (29). Because most of these reports involved technical grade PCP (the type of PCP probably used at the SWP site), it is possible that contaminants in the PCP contributed to the dermal effects.
PCP-containing dusts are irritating to the eyes and nose. Nasal irritation has been reported to occur after exposure to PCP air concentrations of 300 ug/m3 (30). The Occupational Safety and Health Administration standard for occupational exposure to PCP (500 ug/m3) is more than 200 times greater than the maximum PCP concentration detected near the site. Therefore, it is unlikely that inhalation and dermal contact with PCP-contaminated dust from the SWP site would result in eye and nose irritation.
Recent studies conducted by the National Toxicology Program indicate that PCP is carcinogenic in laboratory mice (31). However, these experiments were conducted using technical grade PCP containing about 10 percent impurities. Because some of the impurities are carcinogens, the carcinogenic risks associated with exposures to PCP cannot be unequivocally determined.
Remedial activities conducted in April 1990 involved the excavation of on-site contaminated soils. The results of air monitoring studies performed at that time did not indicate the presence of PCP in airborne particulates at concentrations above the detection limit (< 0.01 ug/m3). Low air concentrations of CDDs and CDFs were detected during this monitoring. However, the reported air concentrations of TCDD equivalents (0.0074 - 0.0899 pg/m3) do not pose a significant health hazard. In this study, it was reported that the concentrations of contaminants in an air sample collected upwind of the soil excavation area were equal to or exceeded the air concentrations in downwind locations (11). Therefore, there may be other off-site sources in addition to the SWP facility.
No other monitoring data were available to determine if there are other ambient air contaminants that could be responsible for the conjunctivitis and other eye problems reported by neighborhood residents.
Also, no air monitoring data were available to determine if there have been elevated air concentrations of benzene or other site-related chemicals associated with leukemia and other types of cancer.
Recent studies have reported the presence of CDDs and CDFs in soil/sediment samples collected from drainage ditches east of the facility (Table 5). Octachlorodibenzodioxin and octachlorodibenzofuran, the least toxic congeners, were detected in the highest concentrations. However, low concentrations of TCDD, the most toxic congener, were also detected in some samples.
The results of laboratory studies have indicated that some CDD congeners are potent carcinogens in animals; however, the available evidence for the carcinogenicity of CDDs and CDFs in humans is inconclusive (32). In humans, the only confirmed health effects attributed to TCDD exposures are chloracne and transient increases in liver enzymes (32).
Contact with sediments in the off-site drainage ditches could result in exposure to CDDs, CDFs, and other site-related chemicals. The health impact of such exposures would depend on the frequency and length of exposure. Frequent and long-term exposure to these contaminated ditch sediments could pose a public health hazard. However, the ditches, where elevated concentrations of CDDs and CDFs were found, run parallel to Central of Georgia Railroad tracks and are located in a non-inhabited area. Therefore, contact with these ditches would likely be on an infrequent and short-term basis. Such contacts would not be expected to pose a significant public health hazard.
There have been reports from citizens of dermal irritation and burns resulting from contact with soil in these ditches. The available analytical data do not provide an explanation for such reports. It is possible that "hot spots" of contamination exist or previously existed in the ditches. Therefore, it would be prudent to discourage public access to the ditches until the contamination has been thoroughly characterized and remediated if necessary.
B. HEALTH OUTCOME DATA EVALUATION
As previously discussed in the Community Health Concerns section, a private consultant conducted a health survey of residents living near the facility. The study concluded that there was an increased incidence of subjective health symptoms (e.g., headaches, fatigue, eye or nose irritation) and specific illnesses (e.g., diabetes, hypertension, cancer) in residents living near the site (1). The Division of Health Studies (DHS), ATSDR, reviewed this study and determined that the conclusions were not valid. DHS noted the following deficiencies in the study:
(1) Comparison of the study and control groups is inappropriate without sociodemographic variables to demonstrate that the two groups are similar except for the presence of a putative source of exposure (i.e., the site). The report does not perform an adequate adjustment to make a valid comparison.
(2) Table 6 shows numerous disparate symptoms reported by the study group. Such disparity does not focus on a specific health complaint that may be related to a hazardous substance, and at times is associated with recall bias.
(3) The definition of statistical significance at p < 0.10 creates a greater possibility of accepting an association that is not causal in nature. A p-value of 0.05 is more commonly used, and the use of a p-value of 0.10 should be justified.
The Georgia Department of Human Resources (DHR) examined the incidence of nine types of cancer that they believed could be related to chemicals found at the site. The Georgia DHR concluded that "There was no indication of excess mortality due to the nine cancer types reviewed (3)."
The Division of Health Assessment and Consultation and the Division of Health Studies of ATSDR conducted an independent review of the DHR study. ATSDR concluded that the study was based on a survey of death certificates for the census tract encompassing the Southern Wood Piedmont site. The strength of the conclusion in studies of this type is limited by the resolving power of the study, which depends on factors such as (a) the relatively small population studied, (b) the inclusion of non-exposed people in the census tract that could dilute-out any positive associations, and (c) the long latency period between exposure and appearance of cancer. In addition, the DHR investigation was an ecological study in which exposure and outcome were determined at the group (census tract) level rather than at the individual level. Therefore, although the conclusion of the Georgia DNR study was valid, it is subject to the above limitations. Based on the available data, no definitive conclusion may be drawn concerning the risk of cancer for an individual living near the site based solely on this study's results (33).
C. COMMUNITY HEALTH CONCERNS EVALUATION
Community members expressed concern about adverse health effects that they believe are associated with exposure to hazardous substances from the SWP site (see Community Health Concerns section). Residents were exposed to hazardous substances in groundwater, and were potentially exposed to hazardous substances in off-site soil and ditch sediments. The existing environmental contamination and health outcome data are inconclusive regarding the public health implications of exposure to many of the hazardous substances detected near the site. Therefore, ATSDR will further evaluate these health concerns by conducting a community health investigation (see Public Health Actions in the Recommendations section).
Community members also expressed concern about contamination of fruits and vegetables grown near the site, and of fish in surface waters near the site. Exposure to hazardous substances in fruits and vegetables at levels of public health concern is not likely to occur, based on the information reviewed for this health assessment (see Pathways Analyses Section). Fish from Rocky Creek or Phinizy Swamp have not been analyzed for possible contamination with site-related chemicals. Therefore, it cannot be determined whether consumption of fish from these bodies of water pose a public health hazard. Additional sampling is being recommended to better characterize the potential for off-site migration of contamination into surface bodies of water.
Based on evaluation of the available information, the Southern Wood Piedmont site is categorized as an indeterminate public health hazard.
Contamination of on-site and off-site groundwater with site-related contaminants including polyaromatic hydrocarbons has been detected. The off-site groundwater contamination has affected numerous residential wells in the area. However, it is believed that all homes near the site have been connected to the Richmond County public water system. Therefore, there is currently no known exposure to groundwater contamination. Some residents were probably exposed to contaminants in private wells before their homes were connected to the public water system. ATSDR conducted analyses of exposure to groundwater contaminants during the period from 1985 to 1989, when monitoring data were available for residential wells. ATSDR did not evaluate past exposures to groundwater contaminants; that process would require extensive dose reconstruction procedures based on computer models. The presence of an off-site plume of groundwater contamination in the lower sand aquifer is a potential source of human exposure to hazardous substances if water wells are drilled into the plume in the future, or if existing contaminated wells are used for domestic purposes.
Limited analyses of soil samples from residences north of the site and dust samples from attics of homes near the site did not detect the presence of concentrations of heavy metals that would pose a public health hazard.
Sediment samples from drainage ditches along the eastern boundary of the SWP facility were contaminated with site-related chemicals, including chlorinated dibenzodioxins and chlorinated dibenzofurans. Frequent and long-term exposure to these contaminated ditch sediments could pose a public health hazard. However, the potential for such exposures is diminished because the ditches are located in a non-inhabited area along railroad tracks.
Low concentrations of PCP were detected in ambient air when the plant was operating, but the concentrations were below a level of acute toxicity. Air monitoring conducted recently during site remediation did not detect air contaminants at concentrations that may pose a public health concern.
The bioaccumulation of site-related contaminants in edible plants would not be expected to pose a health hazard. Insufficient information is available to assess the potential health impact on people who consume fish from surface waters in the area.
- Because of the presence of high concentrations of contaminants on the site, public access should be restricted. Warning signs, as required by RCRA regulations, should be posted at the periphery of the facility.
- Private wells that could be affected by contamination from the site should be removed from
service. This recommendation applies to wells being used for either potable or nonpotable
(showering, bathing, garden irrigation) purposes.
Several hazardous chemicals have been detected in residential water wells in the Lower Sand Aquifer beyond the site boundaries. Concentrations of some of these chemicals exceeded levels that are protective of public health. Future installation of water wells within the groundwater contamination plume should be prohibited until concentrations of hazardous substances are reduced to levels that are protective of public health.
- Soil and sediment in the drainage ditches east of the SWP facility should be further characterized to determine the extent and distribution of contamination with site-related chemicals. Time-activity profiles for human activity in the area are needed to assess the potential for human contact with contaminated areas.
- During removal or remedial operations at the site, air monitoring in the breathing zone should be conducted to ensure that contaminants are not released to ambient air at levels of public health concern. Appropriate dust suppression techniques should be used to prevent off-site migration of contaminated dusts. On-site workers should be protected in accordance with Occupational Safety and Health Administration regulations and National Institute for Occupational Safety and Health recommendations.
- In accordance with the Comprehensive Environmental Response, Compensation, and Liability
Act (CERCLA), as amended, the Southern Wood Piedmont Petition Site has been evaluated for
appropriate follow-up health activities. Based on the information reviewed, the community needs
assistance in assessing its potential for exposure; therefore, community health education is
indicated. In addition, the community has expressed concerns about adverse health outcomes.
Because of these concerns, the following activities will be considered: a case study, a disease and symptom-prevalence study, and a community health investigation. If additional data become available, ATSDR will reevaluate this site for any further follow-up.
PUBLIC HEALTH ACTIONS:
- Actions Taken:
- As of October 1991, EPA indicated that recommendations 1 - 4 had been implemented. In addition, EPA indicated that it intends to conduct studies to further characterize contamination in off-site soils and ditch sediments.
- At the community's request, ATSDR delayed its meetings until January 11, 1992. Two public availability meetings (one at Butler High School and one at Clara Jenkins Elementary School) were held. ATSDR staff met with citizens one-on-one and in small groups to discuss the Public Health Action Plan and to gather community input.
- Actions Planned:
Based on its evaluation of the data and the recommendations made by the Health Activities Recommendation Panel, ATSDR will conduct the following health actions.
- Community Health Investigation -- ATSDR will investigate health concerns of residents near Southern Wood Piedmont to find out if illnesses are caused by chemical exposure. To find out who may have been exposed in the past, a dose reconstruction investigation will be conducted.
- Community Health Education -- Community members will be given information and education to help them understand whether they have been or might be exposed to hazardous substances in the environment and what exposure could mean for their health. ATSDR will meet with the Richmond County Task Force on Southern Wood Piedmont to help exchange information with the community.
|PREPARERS OF REPORT|
|Health Effects and Environmental Assessors:||Kenneth G. Orloff, Ph.D, DABT|
Assistant Director for Science
|Joseph L. Hughart, MS, MPH, PG|
Environmental Health Specialist
|ATSDR REGIONAL REPRESENTATIVE|
|Regional Representative:||Chuck Pietrosewicz|
Senior Regional Representative
Regional Services - IV
(1) Lon Q. Hesla, Health Consultation: Southern Wood Piedmont Company, RCRA Site (RC-86-005) Augusta, Georgia, February 13, 1987.
(2) Richard Bird, Adult health problems reported by residents living near a wood preserving plant in Augusta, Georgia, February 1988.
(3) Thomas W. McKinley, Georgia Department of Human Resources, Cancer deaths among residents near Southern Wood Piedmont, Letter to Maurice G. Patton, April 4, 1988.
(4) George McElvene, Richmond County Water and Sewage Department, Personal communication, April 9, 1990.
(5) C. Pietrosewicz, Agency for Toxic Substances and Disease Registry, Memorandum to Ken Orloff, April 16, 1991.
(6) GeoTrans Inc., Analysis of groundwater flow in the recent alluvium and lower sand aquifers at the Southern Wood Piedmont site, Augusta, Georgia, November 1989.
(7) Edwin A. Woolson, Ronald Thomas, and Peter Ensor, Survey of Polychlorodibenzo-p-dioxin Content in Selected Pesticides, Jour. Agr. Food Chem. 20(2), pp. 381-384, 1972.
(8) H. Hagemmaier and H. Brummer; Isomerspecific Analysis of Pentachlorophenol and Sodium Pentachlorophenate for 2,3,7,8-substituted PCDD and PCDF at sub-ppb Levels; Chemosphere 16 pp. 1759-1764, 1987.
(9) D. E. Rapp, Industrial hygiene survey for pentachlorophenol exposures during wood treating operations, Southern Wood Piedmont Company, Augusta, Georgia, Dow Chemical Company, February 15, 1977.
(10) Environmental Services Division, Environmental Protection Agency - Region IV, Ground Water Monitoring Evaluation, Southern Wood Piedmont, Augusta, Georgia, November 1987.
(11) Geraghty & Miller, Inc., Air Quality Investigation During Soil Excavation/Remediation, Southern Wood Piedmont Company, June 1990.
(12) U.S. Environmental Protection Agency, Interim Procedures for Estimating Risks Associated with Exposures to Mixtures of Chlorinated Dibenzo-p-Dioxins and -Dibenzofurans (CDDS and CDFs) and 1989 Update, EPA/625/3-89/016, March 1989.
(13) Olfacto-Labs, Augusta Creosote Case: Chemical Analyses, El Cerrito, California, August 9, 1988.
(14) Sharon H. Snead, Georgia Department of Natural Resources, Southern Wood Piedmont, Augusta: Area survey and sample collection in cooperation with EPD hazardous waste program, March 28, 1986.
(15) Surface Drainage Map With Soil Quality Data, Wood Preserving Constituents, Law Environmental Services, July 1986.
(16) McCrone Associates, Letter to Mr. David Sapp - Long, Weinberg, Ansley and Wheeler, April 17, 1989.
(17) Geraghty & Miller, Inc., Soil and Ditch Sediment Investigation at the Southern Wood Piedmont Company, Augusta, Georgia, Former Wood Treatment Facility, September 1990.
(18) U.S. Environmental Protection Agency, Results of Specified Analysis, Corrected Data, 90-914, Southern Wood Piedmont, Augusta, Georgia, memo from Robert W. Knight to Bill Bokey, December 10, 1990.
(19) U.S. Environmental Protection Agency - Region IV, Facts, Findings, and Administrative Order, Docket No. 4-UICC-038-89, July 8, 1989.
(20) Law Environmental Services, Inc., Constituents Statistically Exceeding Background at 0-6" Depth, Figure 2, Job No. 55-5270, not dated.
(21) ERT, Ambient air sampling and analysis for chlorinated phenols at Southern Wood Piedmont Company, Augusta, Georgia, Draft Final Report, August 1988.
(22) Chatten Cowherd, Jr., et al, Rapid Assessment of Exposure to Particulate Emissions From Surface Contamination Sites, EPA/600/21, Office of Health and Environmental Assessment, EPA, Washington, D.C., 1985.
(23) U.S. Environmental Protection Agency, Hazardous Waste Land Treatment, EPA SW-874, Office of Water and Waste Management, September 1980.
(24) Nelson T. Edwards, Polycyclic Aromatic Hydrocarbons in the Terrestrial Environment - A Review, Jour. Environ. Quality, 12 427-441, 1983.
(25) ATSDR, Draft Toxicological Profile for Naphthalene and 2-Methylnaphthalene, October 1989.
(26) Robert Berkow, editor-in-chief, The Merck Manual, 14th edition, Merck Sharp & Dome Research Laboratories, Rahway, N.J., page 1089, 1982.
(27) S. Griffith, S. Irene, and H. Choudhury. Subchronic toxicity studies of PAHs in mice (abstract). The Toxicologist 10(1) 348, 1990.
(28) ATSDR, Toxicological Profile for Arsenic, ATSDR/TP-88/02, March 1989.
(29) ATSDR, Toxicological Profile for Pentachlorophenol, ATSDR/TP-89/19, December 1989.
(30) American Conference of Governmental Industrial Hygienists Inc., Documentation of the Threshold Limit Values and Biological Exposure Indices, 5th edition, Cincinnati, Ohio, 1986.
(31) S. Irene, R. Rubenstein, S. Segal, et al, Carcinogenicity assessment for pentachlorophenol (abstract), The Toxicologist, 10(1) 349, 1990.
(32) ATSDR, Toxicological Profile for 2,3,7,8-Tetrachlorodibenzo-p-dioxin, ATSDR/TP-88/23, June 1989.
(33) H.C. Selvin, Durkheim's "Suicide" and Problems of Empirical Research, Amer. Jour. Sociology , 63 607-619, 1958.
Southern Wood Piedmont Health Assessment - Response to Public Comments
Comment: During the operating life of the facility, plant wastewaters were handled in various ways. From approximately 1927 to 1973, plant effluent was processed through an oil/water settling separation and recovery system. Process water that could have contained wood preserving constituents was then discharged to drainage ditches.
In 1973, an unlined surface impoundment was constructed to act as a biological treatment unit to process wastewater containing wood preserving constituents. Processed wastewater was then discharged to the Publicly Owned Treatment Plant (POTW) under an approved permit.
In 1986, the surface impoundment was closed under terms of a closure plan approved by the Georgia Department of Natural Resources. Wastewater was then processed in an on-site wastewater treatment facility. After treatment, process water containing wood preserving constituents was discharged to the POTW.
Response: The Site Description and History section of the health assessment was expanded to include this additional information on wastewater discharges.
Comment: The commentor did not agree with the use of the word "high" to describe the concentrations of wood treatment chemicals in the groundwater.
Response: Groundwater from private wells surrounding the facility has been contaminated with concentrations of chemicals that render the wells unsuitable for potable and nonpotable purposes. Hence, the contaminant concentrations were characterized as "high."
Comment: Only an estimated 28 acres was used for wood preserving activities. The remainder of the 78 acres was either undeveloped wooded area, or used for preparation activities that would not be considered wood preserving activities.
Response: The health assessment was revised to include this information.
Comment: In the Site Description and History section, it is implied that all four wood preservatives were used from the time the plant was constructed. The approximate dates of wood treatment preservative use at the facility are as follows:
|PCP||Mid 1960s to 1988|
|CCA||1981 to 1988|
|ZMA||Mid 30s to Mid 40s|
Response: The health assessment was revised to include this information.
Comment: SWP was issued a final post-closure care permit with the signing of a consent order that settled the outstanding issues of SWP's appeal of the final permit issued by Georgia Department of Natural Resources. This agreement and effective date of Post-Closure Permit was March 22, 1989.
Response: The health assessment was revised to include this information.
Comment: Page 3: SWP has no on-site groundwater extraction wells. Groundwater extraction sumps are present.
Response: The text was revised as appropriate.
Comment: The health assessment stated that there is a large brick manufacturer (Babcock and Wilcox) located north of SWP. The commentor identified this facility as Thermal Ceramics, Inc.
Response: The health assessment was revised to include this information.
Comment: The commentor noted that there has been extensive remediation along the southern border of the facility since the ATSDR site visit.
Response: In the health assessment, the conditions at the site at the time of the ATSDR site visit on December 18, 1989 are reported. This information is included for historical reference purposes. ATSDR acknowledges that current conditions at the site may be different because of removal/remedial activities conducted since that time.
Comment: In the health assessment, it was stated that class action suits had been filed against SWP. The commentor stated that one class action suit had been filed against SWP.
Response: The health assessment was revised to include this information.
Comment: In the Community Health Concerns section, it was stated that several specific illnesses had been attributed to exposures from the site. The commentor stated that, "This sentence should be corrected to read: Plaintiff's attorneys have contended that specific illnesses such as dermal keratosis, chronic conjunctivitis, and cancer (skin, leukemia) are attributable to exposures from the site. To date no medical authorities have confirmed these allegations."
Response: The statement in the health assessment reflects information that was reported to ATSDR by residents and attorneys involved in the legal suit. ATSDR offers no opinion as to whether any individual adverse health outcome is attributable to hazardous chemical exposures from the facility.
Comment: The lower sand aquifer is separated from the surficial aquifer by a thin, silty, clay aquitard which pinches out east of the site.
Response: The health assessment was revised to include this information.
Comment: The commentor "believes page 7 to be an inaccurate representation of the facts. The analysis on Table 1 were obtained by analyzing MW-1C. This well is screened in the recent alluvium, not in the lower sand aquifer. The analysis is of the oil phase, not the dissolved constituents in groundwater." Table 1 should be more appropriately entitled, On-Site Characterization of Contamination in the Recent Alluvium. It might also be appropriate to have a Table 2 that shows the groundwater contamination in the production area in the lower sand aquifer.
Response: The health assessment was revised to indicate that the data in Table 1 were derived from samples collected in the recent alluvium. It is noted that the contaminant concentrations are lower in the Lower Sand Aquifer.
Comment: The commentor challenged a statement on page 8 of the draft health assessment, which described the formation of chlorinated dioxin congeners during pressure treatment of wood with pentachlorophenol.
Response: The statement in the health assessment was clarified, and a reference source was cited.
Comment: Table 2: The commentor asked where the groundwater samples were taken and what the actual results were. The commentor stated that SWP has analyzed the most representative on-site well for dioxins and furans and the results in all cases have shown no detectable levels. The commentor stated that, "estimated concentrations", as you indicate these are, serve no purpose in light of the above results over several periods."
Response: The information available to ATSDR did not indicate the specific location where the referenced groundwater sample was collected. The values in Table 2 are presented as they were reported in the referenced document. Dioxins were also found in on-site soil (Table 2) and are known contaminants of pentachlorophenol. Therefore, ATSDR believes the reported results are valid.
Comment: The commentor referred to the dioxin air monitoring data on page 10 of the draft health assessment. The commentor stated, "TCDD was found in only one sample. This was detected upwind of the site and in all likelihood from a source other than SWP. The ranges you have quoted as being between 0.0074 to 0.0899 pg/m3 are based on using one-half the detection limit for all non-detects. You have stated on page 31 that the only detected concentration of 2,3,7,8-TCDD was upwind of the SWP site. We feel that the statement should be revised as follows:
"Low concentrations of 2,3,7,8-TCDD were detected in only one sample at extremely low levels. The sample was collected at an upwind location from Southern Wood Piedmont indicating a source other than SWP. CDF's were detected in extremely low levels both upgradient and side gradient of SWP during one sample period. Using EPA's Toxic Equivalency Factor approach (11), it was reported that the air concentrations of 2,3,7,8-TCDD equivalents ranged from 0.0074 to 0.0899 pg/m3. It should be noted, however, that the TEFs are based on one-half the detection limit being used in the case of a non-detect for the development of the TEF ranges. Most of the actual analytical results indicated non-detect."
Response: In Table 11 of the referenced study, it is reported that 2,3,7,8-TCDD was detected in two samples (4L and 5L), not one. On page 12 of the referenced study, it is stated that the TCDD equivalents were calculated by multiplying the detection limit concentration (not one - half the detection limit) by the Toxicity Equivalent Factor. The health assessment was revised to include this information.
Comment: In reference to page 10 of the health assessment, the commentor stated that the term "lower aquifer" should be changed to "lower sand aquifer."
Response: The health assessment was revised as appropriate.
Comment: SWP is submitting the last status report on the site which indicates that the groundwater in the lower sand aquifer flows to the northeast. SWP does not agree with the Agency's conclusion regarding contaminated groundwater dispersion. Corrective action status report and Figure 1 are submitted so that groundwater flow and contamination can be properly analyzed by the Agency.
Response: ATSDR concurs that groundwater in the Lower Sand Aquifer flows northeast. ATSDR's conclusions regarding migration of contaminants in surface water and groundwater are consistent with conclusions developed by SWP's consultant in the Corrective Action Plan, Segment 3, dated July 18, 1986 (see pages 1-3, 1-4, 1-10, 1-11, 1-15 through 1-17, 3-1 and 3-2 of the Corrective Action Plan). ATSDR properly analyzed groundwater flow and contaminant migration in the health assessment. Contaminants migrated from the SWP site via a ditch to Hole #2, located 2,400 feet southeast of the site between New Savannah Road and Gravel Pit Road. Contaminants in the ditch would have been hydraulically connected to groundwater. Upon entering the Lower Sand Aquifer, contaminants would migrate northeast through ground water, and may have intercepted residential water wells along New Savannah Road and Gravel Pit Road. Surface water in streams located between New Savannah Road and Gravel Pit Road is hydraulically connected to Phinizy Swamp. Phinizy Swamp is located only a few hundred feet from the streams. Phinizy Swamp and its tributaries are discharge zones for surface water and for ground water.
Comment: Page 16: SWP has no record of any discharge in ditches on the north side of Nixon Road and no record of any discharges on Winter Road.
Response: See pages 1-10, 1-15, 1-16, and 3-3 of the Corrective Action Plan, Segment 3, prepared by SWP consultants, dated July 18, 1986, for descriptions of how contaminants may have migrated from the SWP site to ditches north of Nixon Road.
Comment: Page 16: This discussion implies that ATSDR believes that SWP is the source of groundwater contamination on Gravel Pit Road. SWP is submitting a location map with laboratory analytical sheets and chain of custody forms that SWP believes indicates that it is highly unlikely that SWP is the source of contamination along Gravel Pit Road.
Response: Groundwater monitoring results, ditch sediment results, and groundwater elevation data indicate that SWP was a potential source of contamination of wells located along New Savannah Road and Gravel Pit Road. TCE was not detected in groundwater at the SWP site, but it was detected in one residential water well along Gravel Pit Road. Therefore, other sources of groundwater contamination may have been present in the vicinity of Gravel Pit Road. Although the presence of groundwater contaminants that are not related to SWP was discussed on page 28 of the draft health assessment, a statement has been added to the section on Sources of Contamination in the Groundwater Contamination portion of the Pathways Analyses to indicate that other sources of groundwater contamination may have existed in the vicinity of Gravel Pit Road.
Comment: SWP acknowledges that wastewater discharges [that] may have contained wood preserving constituents were discharged into the ditches as the Agency states. What evidence does the Agency have which supports their statements regarding discharges of creosote, zinc meta-arsenate, PCP and CCA? SWP does not believe evidence supports the statement that these preservatives were discharged into ditches.
Response: See pages 1-2, 1-3, 1-9, 1-15, 1-16, 3-1 and 3-3 of the Corrective Action Plan, dated July 18, 1986, which was prepared by SWP consultants. The information reported by SWP consultants and a site visit report prepared by representatives of the Georgia Department of Natural Resources, dated March 28, 1986, formed the basis for the statement.
Comment: On page 18 of the health assessment, the commentor suggested the following change: "When the plant was operating, prior to the late 1960's, wastewaters were discharged to drainage ditches ..."
Response: The health assessment was revised as appropriate.
Comment: On page 21 of the health assessment, the commentor suggested the following change: "Analyses of the samples revealed the presence of low concentrations of CDDs and CDFs (Table 2), found upwind, but no detectable pentachlorophenol (10)."
Response: In Tables 11, 12, and 13 of the reference cited (10), it was reported that CDD and CDF congeners were detected in all samples - both upwind and downwind of the site. No change was made in the health assessment.
Comment: The commentor referred to the second paragraph on page 24. The commentor stated that concentrations of site-specific constituents were not detected at all. The corrected wording should be as follows: "Although the Chemical Oxygen Demand (COD) of the downstream water sample was higher than the upstream sample, concentrations of the site-specific chemicals were not detected (13)."
Response: The text was revised as appropriate.
Comment: Page 25, paragraph 2: Fish tissue samples were reported analyzed in the 1987 and 1988 TSSM studies reported by the Georgia Department of Natural Resources. The only chemical detected was zinc.
Response: This document was not provided to ATSDR for review.
Comment: Page 27, paragraph 2: SWP, in an earlier comment directed at statements on page 16 of the draft health assessment, stated that they believe it is highly unlikely that SWP contributed to the contamination in the private wells along Gravel Pit Road. They submitted a well location map and laboratory and field data sheets as verification of their position. The data that was attached is to allow ATSDR to form its own conclusion. For these reasons, SWP believed that the statement is more accurate if it is worded as follows, "Furthermore, as recently as January 1989, PAH contamination was discovered in private wells being used by residents along Gravel Pit Road, however, this contamination is not likely associated with Southern Wood Piedmont."
Response: ATSDR has concluded that SWP is a potential source of contaminants detected in residential water wells along Gravel Pit Road. Other sources of groundwater contamination may have existed in the vicinity of Gravel Pit Road (see page 28 of the draft health assessment). The health assessment has been revised to directly reflect the conclusion that other sources of contamination may have existed in the vicinity of Gravel Pit Road.
Comment: ATSDR received correspondence from several residents who lived in neighborhoods surrounding the SWP facility. These residents listed numerous health problems that they and other family members have experienced. Some of the medical conditions listed were cancer (colon, skin, brain, lung, kidney, bladder, liver, leukemia, Hodgkins disease), kidney and bladder disease, allergies, sinus problems, headaches, etc. The residents further expressed concern that these problems might be related to past or current exposures to contaminants from the site.
Response: Community health concerns are explicitly noted in the health assessment. In addition, the Public Health Implications section of the health assessment discusses adverse health effects that could result from exposures to site contaminants. However, it is not the purpose of a health assessment to evaluate the medical status of individuals to determine if their health problems are related to exposures to hazardous substances from the site. The establishment of causal relationships between site-related exposures and adverse disease outcomes in individuals is beyond the scope of the health assessment process.
Comment: The health assessment does not address the potential impact of contamination from the SWP facility on wildlife in Phinizy Swamp and Rocky Creek.
Response: ATSDR agrees that this is a valid concern. However, ATSDR's mandated responsibility is to assess the impact of environmental contamination on public health. ATSDR has no responsibility for assessing the impact of hazardous substances on wildlife in the environment. That responsibility rests with the U.S. Environmental Protection Agency and other federal, state, and local agencies.
Comment: The following comment was included in the Georgia Environmental Protection Division draft dated May 17, 1990:
"If CDDs and CDFs are present in off site media, their presence could pose a public health hazard since they are more toxic than PCP."
This significant statement about dioxins was deleted from the public draft dated September 1, 1990.
Response: At the time the May 17 draft was released, ATSDR did not have analytical data for CDDs and CDFs in on-site or off-site environmental media. Because these compounds are known to be contaminants of PCP, ATSDR acknowledged concern over their possible presence in environmental media (page 6).
After the May 17 draft was released, ATSDR received additional information which indicated that CDDs and CDFs had been detected in on-site and off-site environmental media. This new information was included in the September 1 draft health assessment (pages 9-10) and was further discussed in the Public Health Implications Section (pages 30-31). Therefore, the health assessment was revised to indicate that CDDs and CDF were documented contaminants rather than hypothetical contaminants.
Since the September 1 draft health assessment was released, ATSDR has received additional data on the presence of CDDs and CDFs in off-site soil/sediment samples. This information has been included in the final health assessment (Table 5). A discussion of the health effects of these compounds has also been added to the Public Health Implications section.
Comment: Recommendation number 5 of the May 17, 1990, health assessment was omitted, which read as follows:
"(5) When indicated by public health needs, and as resources permit, the evaluation of additional relevant health outcome data and community health concerns, if available, is recommended."
Response: This standard recommendation, which is included in all ATSDR health assessments, was inadvertently omitted from the September 1 draft health assessment. It has been included in the final health assessment.
Comment: A commentor noted from personal experience that contact with soil in a drainage ditch near the site resulted in dermal irritation and lesions.
Response: This information was added to the Community Health Concerns section of the health assessment.
Comment: A commentor asked if trichloroethylene (TCE) has been found at other wood treating sites.
Response: The major industrial use of TCE involves degreasing of metal parts. TCE has no direct use in the wood treating industry. TCE was not identified as a contaminant at the SWP facility.
Comment: A number of people fish in ponds in this area as well as Rocky Creek. The people report that the pears and peaches produced by trees in the area taste like contaminated water.
Response: ATSDR's ability to respond to these concerns is limited by the absence of relevant data. To the extent possible, these issues were addressed in the health assessment (Section D - Bioaccumulation of Contaminants in the Food Chain).
Comment: Workers and residents have used waste wood from the Southern Wood Piedmont site to heat their homes. Creosote treated wood was a favorite fire starter. The health assessment does not mention burning of treated wood either on-site or off-site.
Response: ATSDR recommends against the use of wood treated with creosote, PCP, CCA, or other wood preservatives for heating homes. ATSDR is not able to assess the potential health impact of previous exposures through this pathway. However, because the facility is closed and no treated wood remains, it does not appear that this exposure pathway is of current concern.
Comment: If the off site groundwater contains dioxins, then public water lines may not remove the threat of contamination. The December 30, 1988, Federal Register notes that equipment can be contaminated even after accumulated residuals are removed. Old water heaters and water lines from well connections could still pose a health hazard.
Response: To determine if such a problem exists, it would be necessary to analyze for dioxins in a tap water sample from a home that is currently connected to the public water system, but which previously used dioxin-contaminated groundwater. ATSDR is not aware that any such analyses have been conducted, hence no assessment can be offered.
Comment: The "Adult Health Problems Reported by Residents Living Near a Wood Treatment Plant in Augusta, Georgia" was not properly completed and was compared to the wrong population. Death certificates from 1979-86 covered too short a period for this study. A new health survey should be conducted with special emphasis on the diseases that the chemicals cause. Death certificates should be analyzed for not less than a 20-year period.
Response: A health assessment relies on available data and information. The weaknesses of the available health outcome studies were discussed in the health assessment. The final health assessment contains a statement regarding possible follow-up health studies by ATSDR.
Comment: On October 10-12, 1990, flooding occurred at the SWP facility. Concern was expressed about whether the flood could have transported contaminants from the SWP site to neighboring property.
Response: ATSDR agrees that flooding at the site may transport contaminants off-site. However, no post-flood sampling results have been provided to ATSDR for evaluation to determine if off-site transport of contamination has occurred. If such data become available, they will be addressed, if warranted, in an addendum to the health assessment.
Comment: The neurotoxic effects of lead and arsenic were cited, and it was noted that neurotoxic effects on the developing nervous system may occur at doses lower than those considered to be safe for adults. The commentor stated that, as a clinical psychologist, he had examined a number of children in the area and concluded that "A diagnostic finding has involved intellectual levels somewhat lower than prediction formulae." The commentor further recommended "... screening or testing for possible effects on neurocognitive and neurobehavioral sequelae to exposure."
Response: ATSDR concurs that children and the developing fetus are more susceptible than adults to the neurotoxic effects of lead. However, lead was not identified as a contaminant at the SWP site. Significant off-site contamination or exposure to arsenic has not been documented. Off-site contamination and exposure to polyaromatic hydrocarbons (PAHs) has probably occurred; however, neurotoxic effects have not been reported to result from PAH exposures.
ATSDR recommendations for follow-up health studies are presented in the Recommendations section of the final health assessment.
Comment: The commentor stated that the neurotoxic effects of airborne and waterborne exposures to benzene, toluene, xylene, and pentachlorophenol need to be assessed.
Response: Complete data for the concentrations of these chemicals in off-site environmental media are not available, particularly for ambient air while the facility was operating. However, the limited, available data do not document the presence of these contaminants in off-site environmental media at concentrations that would be expected to pose neurotoxic effects.
Comment: The commentor alluded to the air quality study conducted at SWP in April 1990. The commentor stated that the air monitoring was conducted at a time when "little or no remedial work was being done at the site." The commentor stated that much larger quantities of dust could be generated during the next two years when 90,000 cubic meters of soil will be removed. Air monitoring during this time would be necessary.
Response: According to the Air Quality Investigation report, several of the air samples were collected while dirt shaking and truck loading operations were in progress. ATSDR agrees that air monitoring should be included as part of the remedial action plans. This was stated in ATSDR Recommendation number 4. ATSDR will request a copy of the Site Remediation Workplan and review it to determine if adequate dust suppression procedures will be followed and if adequate air monitoring will be conducted during remedial operations.
Comment: The resident requested that an evaluation be made by the ATSDR to determine whether the general area within five hundred (500) yards of the facility should be evacuated during the upcoming two to three year remedial period when 90,000 cubic meters of soil are to be removed from the site.
Response: This concern was addressed in Recommendation number 4 in the health assessment.
Comment: The commentor expressed concern that contamination from the SWP site could reach the Peach Orchard County Well Field, which is located about one - half mile to the southwest of the site.
Response: Hydrogeological pump tests were conducted in the lower sand aquifer at the SWP facility in April 1989. The results of these tests indicated that reversal of the groundwater flow direction in the lower sand aquifer (such that flow is to the west or south) is not expected to have occurred due to short-term or long-term pumping rates at the Peach Orchard Well Field. (GeoTrans, Inc., Analysis of Groundwater Flow in the Recent Alluvium and Lower Sand Aquifers at the Southern Wood Piedmont Site, Augusta, Georgia, November 6, 1989.
Comment: The commentor expressed concern about why certain chemicals that have been reported to be constituents of creosote were not discussed in the health assessment. The specific chemicals mentioned were quinoline, isoquinoline, and beta-naphthylamine.
Response: No analytical data were provided to confirm or deny the presence of these chemicals in on-site or off-site environmental media. No assessment can be offered in the absence of this information.
Comment: Several of the public comments referred to recent reports that CDDs and CDFs had been detected in off-site drainage ditch sediments and soil. The public health impact of potential exposures to this contamination was questioned.
Response: Since the draft health assessment was released for public comment on September 1, 1990, two studies have investigated off-site contamination of soil/sediment with CDDs and CDFs. A study conducted by Geraghty & Miller, Inc. was completed in September, 1990, and a study conducted by the U.S. Environmental Protection Agency - Region IV was completed in December 1990. The results of these studies and a discussion of their public health significance have been added to the health assessment.
Comment: Residents were concerned that groundwater being discharged from the site into the POTW for wastewater contained dioxin, and that the dioxin may accumulate in sludge and eventually bioaccumulate in the food chain. The residents requested that the groundwater receive pretreatment before being discharged into the sewer leading to the POTW, and that the pretreated water be analyzed for the presence of dioxins.
Response: ATSDR agrees that, if present, dioxins may collect in sludge from a wastewater treatment plant and may bioaccumulate in the food chain if the sludge were used for agricultural purposes. It is not known if groundwater being discharged from the SWP facility to the Augusta POTW is contaminated with dioxins. The Georgia Department of Natural Resources (DNR) has authority to develop and enforce wastewater pretreatment standards. The DNR will be provided with a final copy of this health assessment for possible follow-up of this concern.
Comment: The commentor asked if any official from the Center for Environmental Health and Injury Control played a role in the preparation of the SWP Health Assessment.
Response: No official from the Center for Environmental Health and Injury Control played a role in the preparation of this health assessment.
Comment: The commentor provided information to ATSDR on the air release of pentachlorophenol and creosote from a treatment cylinder at the SWP East Point, Georgia, facility which occurred on November 7, 1977.
Response: Since this event occurred at a different facility, it has no direct bearing on the public health impact of operations at the SWP Augusta, Georgia, facility.
Comment: The commentor asked if the residential neighborhood located west of the SWP facility had been tested for site-related contamination, and if present, did the contamination pose a public health hazard?
Response: In 1988-1989, surface and subsurface soil samples from the residential neighborhood located west of the SWP facility were analyzed for copper, chromium, and arsenic. In 1990, surface soil samples from this area were analyzed for chlorinated dibenzodioxins and chlorinated dibenzofurans. The soil contaminant concentrations reported in these studies would not be expected to pose a public health hazard.
Comment: The commentor questioned the validity of the soil/sediment analyses conducted by EPA on September 27, 1990, because of excessive holding time of the samples before analyses.
Response: The data provided to ATSDR by the EPA noted that the acceptable holding time for the acid fraction (which would include phenolic compounds) was exceeded. Therefore, ATSDR did not use this data in its health assessment. The analytical data for chlorinated dibenzodioxins and chlorinated dibenzofurans was not subject to any qualification and was used as presented.
Comment: The commentor stated that two toxicology consultants had been hired by Geraghty & Miller to evaluate the public health impact of dioxin contamination detected in recently collected on-site and off-site soil/sediment samples. The commentor questioned whether the opinions of the consulting toxicologists were accurately communicated by SWP.
Response: ATSDR conducted its own independent assessment of the dioxin data provided by Geraghty & Miller and EPA. Both of these studies produced similar results (Table 5) and are discussed in the ATSDR health assessment. The evaluation conducted by the toxicology consultants described in this public comment period was neither received nor considered in ATSDR's evaluation. Therefore, the issue raised in the comment is not relevant to the ATSDR health assessment.