PETITIONED PUBLIC HEALTH ASSESSMENT
ESCAMBIA BRUNSWICK WOOD
(a/k/a BRUNSWICK WOOD PRESERVING)
BRUNSWICK, GLYNN COUNTY, GEORGIA
PETITIONED HEALTH CONSULTATION
GROUNDWATER PATHWAY EVALUATION
BRUNSWICK WOOD PRESERVING
BRUNSWICK, GLYNN COUNTY, GEORGIA
EPA FACILITY ID: GAD981024466
December 23, 1997
TABLE OF CONTENTS
Groundwater Exposure Pathway
Groundwater Quality Data
The Agency for Toxic Substances and Disease Registry (ATSDR) received a request from a Brunswick, Glynn County, Georgia, community member to investigate potential health concerns associated with the Brunswick Wood Preserving (BWP). One of the concerns expressed by the individual was about potential exposure to contaminated groundwater that may be migrating from the site (ATSDR, 1993a). In response to this concern, ATSDR reviewed available environmental site data, including information and analytical data provided by the U.S. Environmental Agency (EPA), Georgia Department of Natural Resources (GADNR), the Glynn County Health Department, and the Community Based Environmental Project (CBEP). This health consultation includes the review of available environmental data and an evaluation of potential pathways of exposure to contaminate groundwater.
BWP is a former wood preserving facility located on approximately 84 acres on Perry Lane Road, Brunswick, Georgia (see Figure 1). The site is situated in northwest Brunswick, approximately 5 miles from the downtown area. It is bounded to the south and east by railroad tracks, to the north by Perry Land, and to the west by Burnett Creek (ATSDR, 1992a). The 50-acre production area consisted of two wood treating process areas and a four-acre water-containing surface impoundment (see Figure 2). The site also contains four buried impoundments and a treated pole storage area. Currently, the site is inactive and is completely fenced and posted with a security guard (EPA, 1997a).
The BWP facility was one of four facilities that made up Brunswick Wood Treating Company (EPA, 1991b). BWP treated utility poles and marine piles from 1958 until 1991, when the site was abandoned. The Brunswick facility initially handled only oil-based preservatives (e.g., creosote and pentachlorophenol [PCP]), but by 1970, Brunswick Wood Preserving also had constructed a separate facility for chromated copper arsenate (CCA) wood treatment (EPA, 1991a).
Following treatment by either method, BWP's wood products were dried in drip tracks and stored in treated wood storage areas prior to shipment. The creosote and PCP pressure treatment process generated a large amount of wastewater , which was treated on site prior to its release to surface water bodies, the closest being Burnett Creek. Neither the process areas, the drying tracks, nor the storage areas were underlain with concrete slabs or other material that might prevent wood-preserving compounds from being washed into the surrounding soil (EPA, 1991a). Therefore, as a result of normal operations and storage practices, wood preservatives and spent wastewater were released to surrounding soil.
In early 1991, the BWP declared bankruptcy and completely ceased operations following a fire at the facility. Because of the facility's inability to take corrective actions or continue operating a wastewater treatment system, EPA entered into a Consent Decree with the various owners/operators and initiated a two-phase removal action program. The first phase began on May 29, 1991, and included 1) abating the emergency situation posed by surface water runoff from the site due to the wastewater treatment system, 2) draining several small holding tanks, and 3) disassembling the CCA process area (EPA, 1991a).
During the first phase, EPA also conducted a preliminary assessment of environmental media, determining that elevated levels of wood preserving compounds were present in the process area's soil at depths up to 9 feet below ground surface. Contaminants of concern identified in soils included PCP, polycyclic aromatic hydrocarbons (PAHs), arsenic, and chromium. EPA also identified dioxin, an impurity of PCP. Appendix A provides a description of these contaminants. In addition, EPA conducted limited on-site groundwater monitoring and found that wood preserving compounds released to the on-site soil had migrated vertically to the underlying surficial aquifer beneath the site (EPA, 1991a). EPA also identified and tested more than 50 private wells in the immediate area of the site.
The second phase of the removal action started in January 1992, and included demolition of the CCA process area, the construction of cells for staging of excavated soil, and the excavation of the soil underlying a creosote/PCP impoundment to the west of the creosote/PCP process area. EPA stored more than 127,000 tons of excavated contaminated soil in four on-site lined and covered cells. Depleted funding resources delayed removal activities and stockpiled contaminated soil remained on site for several years. GADNR secured funding in November 1996 to begin removing the cells containing stockpiled soils (Permar, 1996). Soil removal is expected to be completed by early 1998.
In 1992, ATSDR was requested by EPA to evaluate whether BWP site conditions posed health concerns for nearby residents or to individuals accessing the site (ATSDR, 1992a). ATSDR determined that additional data were needed to evaluate two potential exposure pathways that were identified. Those pathways were: 1) exposure may occur if contaminated groundwater beneath the site migrates to off-site areas where groundwater is the source for drinking water supplies, and 2) exposure may occur if people contact potentially contaminated soil on site.
Since the 1992 Health Consultation, ATSDR received a second petition for this site from a Brunswick community member also concerned about potential off-site contaminant migration (ATSDR, 1993a). As follow up to the ATSDR recommendations in the 1992 Health Consultation and in response to the community member's concern, an evaluation of current data concerning this issue is addressed in this consultation.
In February 1997, EPA placed the site on the National Priorities List (NPL) and began final cleanup measures at the site (EPA, 1997a). As a result of this action by EPA, the site was referred to the Superfund Site Assessment Branch at ATSDR where a Public Health Assessment (PHA) is in progress. The PHA will address the nature and extent of contamination, pathways of human exposure, demographics, health hazards, and comparison of mortality and morbidity data for the site.
The land in the vicinity of the BWP site is used for a combination of light industrial, commercial, and residential uses. The Brunswick area has been subject to pollution. The EPA is conducting Superfund cleanups at three other sites, and identified 17 other hazardous waste sites.
Much of the area encompasses large tidal marshes. The marshes are a habitat and feeding area for several species of animals and birds, including migratory birds and endangered species (EPA, 1991b). Tidal marshes border Burnett Creek as it extends from the site toward Cowpen Creek and then into Turtle River (EPA, 1991b). Because of its tidal influence, Burnett Creek flows upstream during high tide and downstream during low tide (EPA, 1991a). Another marsh area, Dixon Swamp, lies east of the site and is subject to seasonal flooding. A concrete flume connects Burnett Creek to the site. Because of the poor integrity of the flume, groundwater is probably leaching into the flume and traveling to Burnett Creek. Although the flume was plugged during removal measures, it has not effectively prevented contaminated groundwater from traveling to Burnett Creek (EPA, 1997a).
Commercial harvesting of shrimp and blue crabs occurs below the U.S. 341 bridge, one-half mile south of the site (EPA, 1991a). A strong commercial seafood fishing industry also prospers in Brunswick. In response to contamination detected in the area attributed to a variety of sources, the GADNR issued a fish consumption advisory for the Purvis Creek, Gibson Creek, and parts of the Turtle River, which are located approximately 2 to 3 miles south-southeast of the BWP site (EPA, 1995). Recreational harvesting of finfish and shellfish for local consumption also occurs along all reaches of Burnett Creek, including areas adjacent to the site (EPA, 1991a; EPA, 1997a). GADNR has not issued an advisory for Burnett Creek; fish monitoring has not been conducted along the creek.
For each environmental medium at a site, ATSDR examines the type and concentrations of relevant contaminants. In this document, ATSDR used comparison values in selecting contaminants for further evaluation within an exposure pathway. Because public water systems are monitored for compliance with EPA's Maximum Contaminant Levels (MCLs), ATSDR selected MCLs as comparison values for this site. MCLs are enforceable drinking water standards. ATSDR also used the Reference Dose Media Guides (RMEGs) for contaminants without established MCLs. ATSDR then considers how people might come into contact with the contaminants. Because the level of exposure depends on the route of exposure and the concentration of contaminants, this exposure information is essential to determine if a public health hazard exist.
Potential exposure pathways for BWP include groundwater and on-site soil pathways. The evaluation of the groundwater pathway is included in this consultation. Information gathered and removal or remedial activities conducted since ATSDR's 1992 Health Consultation is considered. The purpose of this consultation is to evaluate whether contaminants in the groundwater could represent a potential health concern for the public. Contaminants found in on-site soil that could migrate to the groundwater include PCP, PAHs, dioxin, arsenic, and chromium. These chemicals have documented human health effects.
Groundwater refers to bodies of water, or aquifers, that lie under the earth's surface. Groundwater can become contaminated when chemicals migrate or leach from soils or contaminated areas (e.g., lagoons, surface and buried impoundments) into an underlying aquifer. Water typically flows at a slow rate through the aquifer lessening the chance of contaminant migration. Wells and springs are supplied by groundwater, and it is only through drinking or other domestic uses of well and spring water that people are directly exposed to potentially contaminated groundwater. Because the groundwater flows towards Burnett Creek, exposure may also occur indirectly via contact with surface water or via consumption of Burnett Creek fish. ATSDR assessed available site data in its evaluation of the groundwater contamination at the site. A summary of the site's hydrogeology, groundwater use, and groundwater quality data are presented in the following discussion.
The aquifer beneath the site (local hydrogeology) has not been adequately characterized, making determination of groundwater flow and possible contaminant movement from the site difficult. Study of the regional hydrogeology suggests that the aquifer in the area of the site consists of three water-bearing layers: the surficial layer, the Miocene layer, and the deeper, Floridan layer (EPA, 1995). Groundwater beneath the site tends to flow primarily south-southwesterly and toward Burnett Creek; it may also be influenced by tidal fluctuations (Taylor, 1992). Recent observations also suggest that groundwater flow may have been strongly influenced by the drained surface impoundment, as the water- filled impoundment previously served to recharge the groundwater (EPA, 1996).
The Brunswick area relies on groundwater for its potable water supply. Drinking water supplied by groundwater sources are described below.
- Seven deep aquifer municipal wells service approximately 28,000 to 30,000 residents. This is the only source of water for Brunswick's municipal water supply (BWD, 1997). The municipal wells include the Glynco Wells 1 and 2, Brunswick Villa, Goodyear Park, Perry Park, Howard, and Coffin Park wells. These wells are located more than one-mile south of the site.
- More than fifty private wells in the immediate area of the site were identified by EPA in 1991.
During its 1991 preliminary site assessment, EPA collected eight on-site groundwater samples adjacent to the surface impoundment and in the CCA process areas. No samples were taken near the creosote/PCP process area in the southwestern portion of the site. The samples were analyzed for volatile organic compounds (VOCs), PAHs, PCP, and metals. Figure 3 shows the locations of monitoring wells and Table 1 presents the contaminant concentrations recorded at those monitoring wells (EPA, 1991c).
Several wells contained concentrations of VOCs, including benzene (2.3 ppb) and ethylbenzene (0.9 to 51 ppb) below the EPA MCLs. With the exception of chromium (220 ppb), beryllium (6.6 ppb), and lead (89 ppb) detected in Well 4 situated near the western edge of the Lagoon, metal concentrations were below EPA's MCLs or action level for lead. Chromium in the groundwater corresponds to levels (300 to 700 ppm) present in contaminated subsurface soils (3 to 8 feet below ground surface) and possible recharge from the buried impoundments (EPA, 1991a; EPA, 1991b; EPA, 1996). The presence of petroleum products was also noted in wells near the surface impoundment (Wells 2 and 4).
Analytical methods were not adequately sensitive to detect PCP and PAHs above the MCLs because the minimum quantitation limit (MQL) for these compounds exceeded the MCLs. The MQLs used for PCP (20 ppb or 400 ppb) and benzo(a)pyrene (10 ppb or 200 ppb) exceeded their MCLs of 1 ppb and 0.2 ppb, respectively. The MQL is the lowest concentration that is accurately detected by the analytical method.
EPA has installed approximately 12 additional groundwater monitoring wells as part of the remedial investigation (RI) and analyzed the samples for site-related contaminants. The forthcoming RI data will allow ATSDR to more fully evaluate potential exposure via the groundwater pathway. EPA will consider additional groundwater investigations if the RI data do not fully delineate the extent of groundwater contamination with a high degree of confidence (EPA, 1997a).
Brunswick's public water supply, by regulation, must meet EPA safe drinking water standards. The Southeast Region Office of the GADNR Environmental Protection Division (EPD), located in Brunswick, routinely monitors and ensures compliance of the Brunswick public water supply system with these standards. Because compliance is not required for some wood preserving compounds, routine monitoring may not discover the presence of some site-related contaminants. Therefore, to determine whether contaminants had migrated to off-site municipal wells, EPA's Environmental Services Division (ESD) sampled the Brunswick municipal wells in May 1995 and 1996 and analyzed the samples for the complete target compound list and target analyte list which includes site-related compounds. No site-related compounds were found in the municipal water supply wells at levels above their MCLs (EPA, 1997b).
In 1991 and 1992, EPA identified and sampled over 50 private wells adjacent to the site and downstream of Burnett Creek to determine whether off-site migration of site-related contaminants had occurred (see Figure 4) (EPA, 1991a, 1992). The majority of the wells are within a 1-mile radius of the site. Some private wells are as close as 200 yards of the process area, the drained surface impoundment, or the buried impoundments. The water samples were analyzed for wood preserving compounds, VOCs, and metals. The results are presented in Table 2. Of the more than 50 private wells sampled, only one well had detectable levels of wood-preserving compounds, containing the PAHs phenanthrene and pyrene at 10 ppb each (EPA, 1991). Follow-up samples collected from this well failed to confirm the presence of contamination. No VOCs (including benzene) or metals were detected in the samples.
PCP and benzo(a)pyrene were not detected above their respective minimum quantitation limit (MQL) in off-site private wells or on-site monitoring wells (Tables 1 and 2). However, because the MQLs exceeded the health standards (MCLs) for these contaminants, the risk from potential exposure to these contaminants cannot be thoroughly evaluated. In a worse case exposure scenario where contaminant concentrations at the exposure point are equivalent to the MQL, exposures would be considered a public health concern. However, to determine if potential exposure to these contaminants in private wells is a public health concern, the extent of the PCP and benzo(a)pyrene contamination should be determined using appropriate MQLs for PCP and benzo(a)pyrene.
Since the ATSDR 1992 Health Consultation, two additional private wells near the site have been sampled. One well located on Oak Bluff Road about 1.25 miles south of the site was sampled for PAHs and PCP in 1993, and the other well located on Marie Trace about 1 mile east of the site was sampled for VOCs, PAHs, PCP, and metals in 1995. Neither well contained site-related contamination (Lewis, 1993; Adams, 1995). In addition, the CBEP, a governmental, community, and business partnership created to assess environmental conditions in Brunswick, conducted a Brunswick area wide groundwater and a private well sampling effort in December 1996 (EPA, 1996). Four private wells within close proximity to the BWP were sampled. Two of the four wells had been previously sampled in 1991 for wood preserving compounds, but because they lie particularly close to the site or Burnett Creek, they were resampled. The analytical results were not available for review (EPA, 1997b).
Private wells in the immediate vicinity of the site have not been regularly monitored since 1991. EPA has conducted additional characterization of groundwater contamination in its recent RI. Forthcoming groundwater monitoring data from this effort should provide a clearer picture of the extent of groundwater contamination beneath the site and potential, present, and future groundwater pathways.
Consumption of fish from Burnett Creek was identified as a potential exposure pathway. Contaminated groundwater from the site appears to be migrating toward and releasing into Burnett Creek. Certain toxic compounds identified at BWP can accumulate in fish, including PAHs, dioxins, and metals. Because Burnett Creek is potentially contaminated with chemicals that are know to bioaccumulate in fish and no fish samples have been collected from the creek, it is unknown if this pathway is of public health concern. ATSDR cannot fully evaluate this exposure pathway without Burnett Creek fish monitoring data.
No community health concerns have been brought to ATSDR's attention by the Glynn County Health Department (GCHD, 1997). In 1993, ATSDR received a request from a Brunswick citizen to investigate potential exposures to site-related contaminants, including exposure through contaminated groundwater/drinking water supplies. Review of the current data concerning this concern is included in this health consultation. ATSDR will continue to monitor community concern (e.g., communicate with the Glynn County Health Department) as a continuation of the health consultation process.
Based on a review of available data and discussions with local, state, and federal environmental and health officials, ATSDR developed the following conclusions and assigned public health hazard categories to human exposure pathways of concern at the site. A description of ATSDR conclusion categories is provided in Appendix B.
- Consumption of contaminated groundwater associated with BWP is a potential pathway that is difficult to assess at this time. Although environmental media on the BWP property is known to be contaminated, the extent and magnitude of the groundwater contamination in the area has not been fully characterized. EPA completed groundwater monitoring during RI activities in March 1997. The forthcoming data should provide a clearer picture of the extent of contamination in the site area. ATSDR cannot determine whether potential public health hazards exist via this pathway until groundwater data that define the magnitude and extent of contamination are available.
- The Brunswick public drinking water supply poses no apparent public health hazard due to site-related contamination. Site related contaminants were not detected at levels associated with public health effects in EPA's sampling of the Brunswick municipal wells in 1995 and 1996.
- Private wells near the site pose an indeterminate public health hazard. EPA has identified and tested more than 50 private wells located in the immediate vicinity of the site and near Burnett Creek. However, the MQLs used for PCP and benzo(a)pyrene were inappropriate to determine the health risk associated with exposure to these contaminants. In addition, the extent and magnitude of groundwater contamination beneath the site has not been fully and adequately characterized. Many of the private wells have not been regularly sampled for site-related compounds since 1991.
- Consumption of fish from Burnett Creek pose an indeterminate public health hazard. Contaminated groundwater appears to be migrating toward and releasing into Burnett Creek. Therefore, fish in Burnett Creek may accumulate site-related contaminants. Environmental data characterizing contamination of Burnett Creek are needed to complete the evaluation of this pathway.
These recommendations identify actions that ATSDR has determined are necessary to reduce potential health hazards identified and to characterize further potential public health hazards associated with BWP.
- Implement analytical protocols for sampling of potable water using MQLs that are protective of public health.
- Restrict the use of groundwater at the site until extent and characterization of the potential contamination is completed.
- Verify that there are no additional private wells adjacent and down gradient of BWP than those identified in 1991. Determine if private wells immediately adjacent and down gradient of the BWP have been impacted by site related contaminants since 1991 and if the levels are a public health concern. Health standards should be considered when establishing the analytical protocol for sampling of private wells.
- Determine the extent of contamination in Burnett Creek and whether fish, commonly harvested for human consumption, are accumulating site-related contaminants to levels that might pose health hazards to individuals consuming the fish.
ATSDR will review additional data available from the forthcoming RI and include in the PHA.
Susan McAfee Moore
Environmental Health Scientist
Petition Response Branch
Division of Health Assessment and Consultation
ATSDR Regional Representative
Office of the Assistant Administrator
Adams, G. 1995. Memorandum from Glenn Adams, Toxicologist, U.S. Environmental Protection Agency to Jek Jimenez, Drinking Water Section, U.S. Environmental Protection Agency. RE: Results of Potable Wells Water Samples. Brunswick Wood Preserving Site. July.
ATSDR. 1989. Agency for Toxic Substances and Disease Registry. U.S. Public Health Service. Toxicological Profile for 2,3,7,8-Tetrachloro-dibenzo-p-dioxin (June).
ATSDR. 1990. Agency for Toxic Substances and Disease Registry. U.S. Public Health Service. Toxicological Profile for Creosote. TP-90-09. December.
ATSDR. 1992a. The Brunswick Wood Preserving Site Health Consultation. Brunswick Glynn County, Brunswick, Georgia. Agency for Toxic Substances and Disease Registry. May 15.
ATSDR. 1992b. Agency for Toxic Substances and Disease Registry. U.S. Public Health Service. Draft Toxicological Profile for Pentachlorophenol. October. (Update).
ATSDR. 1993a. The Brunswick Wood Preserving Site Petition Decision Summary. Brunswick, Glynn County, Brunswick, Georgia. Agency for Toxic Substances and Disease Registry. December 15.
ATSDR. 1993b. Agency for Toxic Substances and Disease Registry. U.S. Public Health Service. Draft Toxicological Profile for Polycyclic Aromatic Hydrocarbons. October. (Update).
ATSDR. 1993c. Agency for Toxic Substances and Disease Registry. U.S. Public Health Service. Toxicological Profile for Arsenic. TP-92/02. April.
ATSDR. 1993d. Agency for Toxic Substances and Disease Registry. U.S. Public Health Service. Toxicological Profile for Chromium. TP-92/08. April.
BWD. 1997. Personal correspondence between Eastern Research Group, Inc. and Bill Francis, Brunswick City Water Department. January.
EPA. 1991a. Memorandum from Greer C. Tidwell, Regional Administrator, U.S. Environmental Protection Agency to Don Clay, Assistant Administrator, Office of Solid Waste and Emergency Response, U.S. Environmental Protection Agency. Re: Request for a $2 Million Exemption for the Escambia Wood Preserving-Brunswick Site in Brunswick, Glynn County, Georgia.
EPA. 1991b. Removal Action Fact Sheet. Escambia Wood Preserving-Brunswick Site in Brunswick, Glynn County, Georgia.
EPA. 1991c. Groundwater Sample Log. Brunswick Wood Preserving. Brunswick, Glynn County, Georgia.
EPA. 1992. Private Well Water Sample Log. Brunswick Wood Preserving, Glynn County, Georgia.
EPA. 1995. Brunswick/Glynn County Community Based Environmental Project Brunswick, Glynn County Workplan. U.S. Environmental Protection Agency. November.
EPA. 1996. Personal correspondence between Eastern Research Group, Inc. and Brian Farrier, U.S. Environmental Protection Agency.
EPA. 1997a. Personal correspondence between Eastern Research Group, Inc. and Brian Farrier, U.S. Environmental Protection Agency.
GCHD. 1997. Personal correspondence between Eastern Research Group, Inc. and Jane Britt, Glynn County Health Department. January.
Lewis, R. 1993. Personal Correspondence between Richard Lewis, Thorton Laboratories, and Jennie Miller, Environmental Technology. August.
Permar, J. 1996. Toxic Wastes. The Islander. November 4.
EPA. 1997b. Personal correspondence between Eastern Research Group, Inc. and Dorothy Rayfield. Community Based Environmental Protection Agency. January.
Taylor, H. 1992. Letter from Howard Taylor, Removal Operations Section, U.S. Environmental Protection Agency to Rev. Tillman, Glynn County Commissioners January.
On-Site Monitoring Wells
|Lead||ND||ND||ND||45||ND||ND||89||15 (Action Level)|
|Key:||MCL = EPA's Maximum Contaminant Level; ND = Not detected above the minimum quantitation limit.|
|Notes:||(1)||The minimum quantitation limits used for pentachlorophenol (20 ppb for wells 1, 2, 4 and 5 and 400 ppb for wells 3 and 6) exceed the MCL (1 ppb).|
|(2)||The minimum quantitation limits used for benzo(a)pyrene (10 ppb for wells 1, 2, 4, and 5 and 200 ppb for wells 3 and 6) exceed the MCL (0.2 ppb).|
|Monitoring Well Locations|
|1 = North of the surface impoundment in wooded area.
2 = Between the surface impoundment and CCA area, southern most monitoring well.
3 = North of CCA area and west of surface impoundment.
4 = Northernmost monitoring well, west edge of the Lagoon.
|6 = Along the north edge of site (along Perry Lane).
7 = Along Perry Land Road.
8 = Near the southern of the site.
|Maximum Contaminant Concentration (ppb)||
Number of Detections/
||With the exception of two samples, the minimum quantitation limit used for pentachlorophenol (20 ppb) exceeds the MCL (1 ppb).|
|(2)||The minimum quantitation limit used for benzo(a)pyrene (10 ppb) exceeds the MCL (0.2 ppb).|
The wood preserving constituents used during plant operations included creosote and pentachlorophenol. The following is a summary of these wood preserving compounds.
Creosote and PAHs
The type of creosote used for wood preserving is a complex mixture of many chemicals created by high-temperature treatment of coal; it is also known as coal tar creosote. The primary way that creosote contaminates groundwater is through wastewater effluent leaching from unlined settling ponds at wood treatment facilities. Although approximately 300 chemicals have been identified in creosote, the major constituents of health concern are polycyclic aromatic hydrocarbons (PAHs) and phenols. PAHs typically represent 85 percent of a creosote mixture while phenols represent 2 percent to 17 percent (ATSDR, 1990).
Because creosote consists primarily of PAHs, the fate of the mixture often parallels that of PAHs. PAHs are formed during the incomplete burning of coal, oil, wood, or other organic substances. More than 100 PAHs exist and most are ubiquitous in air and soil. While PAHs do not dissolve readily in water, some PAHs may contaminate groundwater. Their mobility in groundwater correlates roughly to their molecular weight. Lower molecular weight PAHs or light PAHs (e.g., acenaphthene, acenaphthylene, anthracene, and naphthalene) tend to volatilize from water and exhibit moderate ability to adsorb to soils (which may hinder their solubility and movement in water). Heavy PAHs (e.g., chrysene, benzo(a)pyrene, and benzo(b)fluoranthene) do not readily volatilize from water and have a stronger tendency to adsorb to carbon in soils, thus impeding movement within groundwater (ATSDR, 1993b). Unlike PAHs, phenols may percolate readily through soils to the underlying groundwater.
Pentachlorophenol is another man-made substance used for wood preserving that does not occur naturally in the environment. Impure pentachlorophenol, the form typically found at hazardous waste sites, exists as dark gray to brown dust, beads, or flakes. Like creosote, the pentachlorophenol found in groundwater is most likely the result of waste leaking from unlined storage lagoons at former wood preserving facilities. Although pentachlorophenol can leach through soils to contaminate groundwater, certain conditions (e.g., acidic soil) may encourage adsorption of pentachlorophenol to soil and reduce the potential for leaching to groundwater (ATSDR, 1992b).
Although metals such as arsenic and chromium are chemicals associated with the CCA wood preserving activity. Although metals can attach strongly to soil and sediment, they often dissolve in water or release from industrial discharges and move deeper in the soil to the underlying groundwater (ATSDR, 1993c, 1993d).
Dioxins and Furans
Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDF) are common impurities in technical grade pentachlorophenol. PCDDs and PCDFs are classes of compounds that are loosely referred to as dioxins and furans, respectively. The more than two hundred possible dioxin and furan isomers belong to one of eight different homologue categories or series. (1) The potency of these isomers varies with structure, with the maximum potency belonging to isomers containing chlorine in the 2,3,7,8-lateral ring positions. Current evidence indicates that the most toxic dioxin is 2,3,7,8-tetrachlorodibenzodioxin (2,3,7,8-TCDD).
No Public Health Hazard
Sites for which data indicate no current or past exposure or no potential for exposure and therefore no health hazard.
No Apparent Public Health Hazard
Sites where human exposure to contaminated media is occurring or has occurred in the past, but the exposure is below a level of health hazard.
Potential/Indeterminate Public Health Hazard
Sites for which no conclusions about public health hazard can be made because data are lacking.
Public Health Hazard
Sites that pose a public health hazard as the result of long-term exposures to hazardous substances.
Urgent Public Health Hazard
Sites that pose a serious risk to the public health as the result of short-term exposures to hazardous substances.
|ATSDR||Agency for Toxic Substances and Disease Registry|
|BWP||Brunswick Wood Preserving|
|CBEP||Community Based Environmental Project|
|CCA||Chromated copper arsenate|
|EPA||U.S. Environmental Protection Agency|
|EPD||Georgia's Environmental Protection Division|
|EDS||EPA's Environmental Services Division|
|GADNR||Georgia's Department of Natural Resources|
|MCL||EPA's Maximum Contaminant Level|
|MQL||Minimum Quantitation Limit|
|NPL||National Priorities List|
|PAH||Polycyclic aromatic hydrocarbon|
|PHA||Public Health Assessment|
|ppb||parts per billion|
|ppm||parts per million|
|RMEG||Reference Dose Media Evaluation Guide|
|VOCs||Volatile organic compounds|
- A permeable rock stratum below that earth's surface through which groundwater moves. The aquifer generally is capable of producing water for a well.
- Any substance that may produce cancer.
- Comparison Values:
- Estimated contaminant concentrations in specific media that are not likely to cause adverse health effects, given a standard daily ingestion rate and standard body weight. The comparison values are calculated from the scientific literature available on exposure and health effects.
- The amount of one substance dissolved or contained in a given amount of another. For example, sea water contains a higher concentration of salt than fresh water.
- Any substance or material that enters a system (the environment, human body, food, etc.) where it is not normally found.
- Detection Limit:
- A minimum concentration that must be accurately and precisely measured by the laboratory and/or specified in the quality assurance plan.
- The amount of a substance to which a person is exposed. Dose often takes body weight into account.
- Environmental Contamination:
- The presence of hazardous substances in the environment. From the public health perspective, environmental contamination is addressed when it potentially affects the health and quality of life of people living and working near the contamination.
- Contact with a chemical by swallowing, by breathing, or by direct contact (such as through the skin or eyes). Exposure may be short term (acute) or long term (chronic).
- Water beneath the surface of the ground in a saturated zone.
- Health Consultation:
- A response to a specific question or request for information pertaining to a hazardous substance or facility (which includes waste sites). It often contains a time-critical element that necessitates a rapid response; therefore, it is a more limited response than an assessment.
- The science of encompassing the behavior of water as it occurs beneath the ground surface.
- Swallowing (such as eating or drinking) chemicals that have gotten in or on food, drinks, utensils, cigarettes, or hands. After ingestion, chemicals can be absorbed into the blood and distributed throughout the body.
- Soil, water, air, plants, animals, or any other parts of the environment that can contain contaminants.
- Petitioned Public Health Consultation:
- A public health consultation conducted at the request of a member of the public. When a petition is received, a team of environmental and health scientists is assigned to gather information to ascertain, using standard public health criteria, whether there is a reasonable basis for conducting a public health consultation. Once ATSDR confirms that a public health consultation is needed, the petitioned health consultation process is essentially the same as the public health consultation process.
- Potentially Exposed:
- The condition where valid information, usually analytical environmental data, indicates the presence of contaminant(s) of a public health concern in one or more environmental media contacting humans (i.e., air, drinking water, soil, food chain, surface water), and there is evidence that some of those persons have an identified route(s) of exposure (i.e., drinking contaminated water, breathing contaminated air, having contact with contaminated soil, or eating contaminated food).
- In risk assessment, the probability that something will cause injury, combined with the potential severity of that injury.
- Route of Exposure:
- The way in which a person may contact a chemical substance. For example, drinking (ingestion) and bathing (skin contact) are two different routes of exposure to contaminants that may be found in water.
- Volatile organic compounds (VOCs):
- Substances containing carbon and different proportions of other elements such as hydrogen, oxygen, fluorine, chlorine, bromine, sulfur, or nitrogen; these substances easily become vapors or gases. A significant number of the VOCs are commonly used as solvents (paint thinners, lacquer thinner, degreasers, and dry cleaning fluids).
1 A homologue is a group of structurally related chemicals that have the same degree of chlorination. There are eight homologues of dioxins, monochlorinated through octachlorinated. An isomer is a substance that belongs to the same homologue class.