PUBLIC HEALTH ASSESSMENT
ALABAMA ARMY AMMUNITION PLANT
TALLADEGA COUNTY, ALABAMA
The Alabama Army Ammunition Plant (ALAAP), a former manufacturer of explosives and chemicals, is situated in Talladega County, Alabama, about 4 miles north of the town of Childersburg. Established in 1941 to produce nitrocellulose (NC), single-base smokeless powder, and nitroaromatic explosives (e.g., 2,4,6-trinitrotoluene [TNT], 2,4-dinitrotoluene [2,4-DNT], 2,6-dinitrotoluene [2,6-DNT], and tetryl), ALAAP was a government-owned, contractor-operated facility during World War II. The plant stored process wastes in unlined ditches and discharged them into several drainage ditches. Operations ceased in 1945, and the facility was on standby status until the 1970s. The facility finally closed in 1988.
As a result of past waste-processing activities and normal facility operations, it seemed likely that explosive materials and other chemicals had contaminated soil and other environmental media. The property consists of the 2,187-acre former manufacturing area (Area B) and the storage portion of the site (Area A). Area A was sold in 1990 to private owners; however, the Army, through the U.S. Army Environmental Center, retains responsibility for its environmental characterization. Both areas are fenced to restrict access.
To address potential health hazards at the site, ATSDR released a public health assessment (PHA) in 1987 and conducted a site visit and released a site summary report in 1995 (ATSDR, 1987, 1995). On the basis of these activities and a review of the available data, ATSDR did not identify any completed exposure pathways but determined that additional data were needed to evaluate potential exposures to contaminated soil, groundwater, and surface water.
Since ATSDR's previous activities, the Army has collected additional environmental samples to further characterize the nature and extent of contamination at ALAAP. On the basis of a review of the additional environmental data and evaluation of potential exposure pathways, including soil, groundwater, surface water/sediment, food chain, and air, ATSDR concludes that the ALAAP site poses No Apparent Health Hazard under current site conditions.
On-site soil samples collected from Area B contained high levels of nitroaromatic compounds and lead; lower and less frequent contamination is present in Area A. Despite these findings, human exposure to on-site contaminated soil at levels associated with health effects is not occurring. A perimeter fence restricts access to soil contaminants thereby limiting the general public's exposure. Hunters and loggers are not expected to have had or continue to have long-term or frequent contact with localized areas containing the highest concentrations of contamination. The Army has remediated several of the contaminated sections in both Area A and Area B and proposed additional cleanup measures for remaining on-site hot spots of contamination. On the basis of available data, access restrictions, and proposed use restrictions, ATSDR concludes that on-site soil should not pose a threat to human health, either now or in the future.
High levels of nitroaromatic compounds and lead have been detected in the groundwater beneath Area B. ATSDR has determined, however, that no one drinks water supplied by Area B contaminated groundwater. Area B obtains water from the county water treatment plant (which draws water from the Coosa River) rather than from on-site groundwater sources. Future developers of Area B would most likely continue to use the county water treatment plant because groundwater use restrictions have been proposed to accompany any land transfer of Area B. Finally, existing municipal and private wells are located more than 2 miles from Area B, or they are located away from the predominant direction of groundwater flow from the site.
Low levels of site-related contamination have been detected in on-site surface water bodies, the Talladega Creek, and the Coosa River. The site fence restricts access to on-site surface water bodies, and Talladega Creek is not used for recreational activities. ATSDR has concluded that the minimal contamination detected in the Coosa River should not pose a health hazard to boaters and anglers who use the river.
Because hunting and fishing have occurred at or near the site, ATSDR evaluated the potential exposure to site-related contaminants through consumption of area game and fish. On the basis of a review of scientific literature on bioaccumulation of contaminants in biota and human exposure dose estimates, ATSDR concluded that consumption of area game by hunters and their families is unlikely to pose any human health hazards. Although fish monitoring data are not available for the Coosa River, unfavorable fishing conditions in the area of the site are likely to reduce fishing activity and potential health hazards associated with consumption of large quantities of potentially contaminated fish.
The Alabama Army Ammunition Plant (ALAAP) is situated in Talladega County, Alabama, about 4 miles north of Childersburg, Alabama (see Figure 1). Although the facility originally consisted of 13,233 acres, after several land transactions, 2,187 acres remain the responsibility of the U.S. government (SAIC, 1996a). The ALAAP site is bounded to the north and northeast by Little Blue Creek and an undeveloped wooded area, to the south and southeast by the Talladega Creek and a mixture of agricultural and residential areas, and to the west and northwest by the Coosa River. Currently, the site consists of paved roads, logging roads, railroad tracks, and bridges. Most of the buildings have been destroyed and the land is overgrown with dense vegetation (SAIC, 1996a).
ALAAP was established in 1941 to produce nitrocellulose (NC), single-base smokeless powder, and nitroaromatic explosives (e.g., 2,4,6-trinitrotoluene [TNT], 2,4-dinitrotoluene [2,4-DNT], 2,6-dinitrotoluene [2,6-DNT], and tetryl). The E.I. DuPont Company operated the facility as a government-owned, contractor-operated facility during World War II. Peak monthly production consisted of 15.6 million pounds of NC, 21.8 million pounds of TNT, and 2.4 million pounds of tetryl. The plant also produced chemical intermediates, including sulfuric and nitric acids, aniline, diphenylamine (DPA), oleum, and sellite. In 1945, the government placed the facility on standby status.
Between 1947 and the 1970s, site property was periodically sold or leased to private holders. The Tennessee Copper Corporation leased the acid plant between 1947 and 1966 for manufacturing acids and organic compounds, and the Beaunit Corporation leased a property north of the site for manufacturing rayon. During this time, the Army also initiated programs to improve conditions in selected manufacturing areas. In the mid-1950s, the government and the Liberty Powder Defense Corporation launched a site rehabilitation program. Approximately 75% of the rehabilitation had been addressed when limited funds prevented completion of the program. In 1973, the Army conducted a controlled burning program to destroy chemical and explosive manufacturing buildings and explosive residues. In the same year, the Army released all but 1,620 contaminated acres of the site to the General Services Administration (GSA) for coordination of sale activities.
In 1977, the Army sold an uncontaminated 1,354-acre parcel containing the NC manufacturing area, the smokeless powder manufacturing area, and 247 associated buildings to Kimberly-Clark, Inc, but they leased back 272 acres to remove equipment from the premises and decontaminate the property. By 1985, the Army had divided the remaining property into Area A, consisting of the eastern portion of the site used primarily for storing and shipping finished explosives and a parcel of woodland outside the site security fence, and Area B, consisting of the former manufacturing area (US AEC, 1997).
Process wastes generated during operations were stored in unlined ditches (i.e., the Aniline Sludge Basin and the Red Water Storage Basin). Two natural culverts (the Crossover Ditch and the Beaver Pond Drainage) conveyed runoff from these waste areas to the Coosa River. In addition, a man-made channel (the Red Water Ditch) originating in the Tetryl Area within Area B transported liquid process wastes to the Coosa River. As a result of the waste handling practices described above and the normal operation of the facility, site-related materials contaminated soil, groundwater, surface water, and sediment.
The Army began investigating environmental conditions at ALAAP in 1977 with an exploratory survey, continuing with Phase I (1980 to 1981) and Phase II (1982) confirmatory studies, and following with a remedial investigation (RI) (1985 to 1986). Data collected through these investigations indicated that widespread contamination by nitroaromatic substances, asbestos, and lead was present in on-site soil, in the shallow groundwater beneath the site, and in sediments in several process and waste areas of the site.
In 1987, the U.S. Environmental Protection Agency (EPA) placed ALAAP on the National Priorities List (NPL) under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), and in 1988, the U.S. Army placed the site on the Department of Defense Base Realignment and Closure (BRAC) list (ESE, 1995a). The facility was closed under the recommendation of the Secretary of Defense in 1988, and the government auctioned Area A to a private buyer in 1990. (Although the former Area A is privately owned, the Army, through the U.S. Army Environmental Center (U.S. AEC) (formerly known as the U.S. Army Toxic and Hazardous Materials Agency), retains responsibility for environmental investigation of both Areas A and B [ESE, 1995a].) In addition to RIs required under CERCLA, the Army conducted investigations under the Community Environmental Response Facilitation Act (CERFA) through the environmental restoration program as mandated by Public Laws 100-526 and 101-510 (SAIC, 1996a).
A total of 12 study areas in Area A and 19 study areas in Area B containing or suspected of containing waste were identified through the RI process, and an additional six waste areas were identified through CERFA activities. Table 1 provides a brief description of the study areas and figures 3 and 4 display the locations of the study areas within Areas A and B, respectively. The specific waste areas are described in greater detail in the Supplemental Remedial Investigation/Feasibility Study for Area A (ESE, 1995a) and Supplemental Remedial Investigation for Area B (SAIC, 1996a) and in Table 2.
The Army, through the U.S. AEC and other Army agencies, implements public involvement and response plans (PIRPs) to establish a communication network between the Army, other federal, state, and local government agencies, and the public (US ACE, 1991). To establish and maintain this network for the ALAAP site, the Army has held public meetings, issued news releases and fact sheets, and established information repositories at the Earle R. Rainwater Memorial Library in Childersburg, Alabama.
Currently, the post is completely shut down and has no ongoing military activity (ESE, 1995a). A perimeter security fence restricts access to the site by unauthorized persons, although breaches were reported in the mid-1980s (ESE, 1986). The former Area A is currently privately owned and used primarily for logging and, to a lesser extent, for grazing approximately 100 head of cattle and hunting. The Army maintains control of Area B. Although the Army has not developed specific arrangements for release of the property, Area B will most likely be used for industrial purposes upon completion of remedial activities (SAIC, 1996a). On rare occasions, and with EPA approval, some of Area B property may be transferred before completion of remediation measures (e.g., before completion of long-term groundwater treatment) (US AEC, 1997). If this occurs, industrial land use restrictions will be imposed.
ALAAP is located 4 miles from the municipality of Childersburg, Alabama. According to a 1990 census, the population of Childersburg is approximately 5,000 people. Figure 5 presents demographic data within a 1-mile buffer of the site. An estimated 1,996 people (including 156 children under the age of 7 and 268 adults over the age of 64) reside within this area. ATSDR reviews demographic information to identify potentially sensitive populations living near or working at the site. The demographic information provided in Figure 5 should not, however, be interpreted as representing the total population exposed to site-related contamination.
Land use in the vicinity of the site consists of a mixture of undeveloped wooded, agricultural, residential, and limited industrial/commercial areas. Approximately 140 residences are located within a 1- to 2-mile radius of ALAAP. Residential property nearest to ALAAP include three farms abutting the southern perimeter of the site and Kymulga, a small residential community located several thousand feet southeast of the site along the Talladega Creek (ESE, 1995b). The closest industrial or commercial properties to the site are Hawk Plastics, a plastics manufacturing facility located along the northern boundary of Area B; Kimberly-Clark facilities, a paper manufacturing plant located just south of the current site boundaries; and a golf course across the Coosa River from the site (US AEC, 1997).
Both Area A and Area B have been used for deer and small game hunting. Between 1969 and 1985, approximately 2,000 bow hunters and 200 gun hunters were permitted for deer hunting annually (ALAAP, 1997a). In 1985, ALAAP closed Area B to hunting but continued to permit approximately 120 hunters per weekend to Area A during hunting season (October and November) (ESE, 1986; ALAAP, 1997a). In 1990, Area A was sold to private holders and has since been unavailable to the public for hunting. Currently, approximately 70 people associated with Area A (owners and their guests) may hunt there between November and January (Heath, 1997).
Both Areas A and B have been used for commercial logging. During the past 5 or 10 years, Area B loggers clear-cut areas to be remediated. Loggers entering areas to be remediated are required to wear Occupational Safety and Health Administration protective gear for logging activities (ALAAP, 1997b). Although logging activities in Area A were discontinued after its sale, commercial logging resumed in 1997 and is expected to continue there for several months, until the area is cleared of trees (Heath, 1997).
The Coosa River and Talladega Creek flow near the site (see Figure 1). The Coosa River may be used for boating and fishing; however, muddy water and thick vegetation create less than favorable fishing conditions (US AEC, 1997). The Coosa River is not used for swimming. Talladega Creek is not used for any known recreational purposes.
Groundwater beneath the site is located in a shallow aquifer consisting of clay residum and in a deep aquifer of fractured carbonate bedrock. Groundwater flows from Area B predominantly in a west north-west direction toward the Coosa River; however, the karstic nature of the aquifer makes it difficult to predict localized groundwater movement (US AEC, 1997). A groundwater divide located approximately between Area A and Area B (near study areas 16 and 19) diverts Area A groundwater toward Talladega Creek (SAIC, 1996a). Recent investigations indicate that groundwater flows into Area A from the north and west (Area B), merges with flow in the Magazine Area (study area 11), and continues flowing toward the Talladega Creek.
Most people residing in the Childersburg's area (living north-northeast of the site) obtain drinking water from the Childersburg's municipal water system, which is the only municipal water system in the vicinity of the ALAAP site that is supplied by groundwater. The wells serving the municipal water works draw water from the deep bedrock aquifer, which lies approximately 300 feet below ground surface. The nearest municipal well to the ALAAP site is located 2.2 miles south of the current installation boundary and not in the predominant direction of groundwater flow from the site. The remaining municipal wells are either located at the water works on the eastern side of Childersburg or located several miles from the site on the western and southern sides of the town. Currently, the ALAAP site does not contain any groundwater supplied drinking water wells, and EPA plans to require groundwater use restrictions as a necessary concomitant to release of the remaining portions of the site (ATSDR, 1995).
Several smaller communities and trailer areas located north of the site are supplied by smaller public systems or private wells that rely on groundwater. No private wells are known to exist within 2-miles downgradient and in the predominant direction of groundwater flow from the site (ESE, 1986; ADPH, 1996).
Drinking water also may be obtained from the county water treatment plant. The treatment plant, which is upstream from the facility, draws water from the Coosa River, and supplies drinking water to Area B, the Kimberly-Clark facility, and the golf course (SAIC, 1996a; ATSDR, 1987).
On February 5, 1987, ATSDR released a public health assessment (PHA), and as a continuation of the PHA process, ATSDR personnel conducted a site visit on August 7 and 8, 1991, and in 1995, further evaluated the site and prepared a site summary report. On the basis of these activities, ATSDR concluded that no completed exposure pathways existed at the site; however, potential exposure pathways requiring further evaluation included contact with nitroaromatic and lead contaminated soil (by hunters and loggers), consumption of contaminated groundwater, and uses of the Coosa River. ATSDR conducted a PHA of the site to determine, if, given no restrictions on land use, it would represent a threat to public health.
In preparing this public health assessment, ATSDR relied on the information provided in the referenced documents. The environmental data presented in this public health assessment are from the remedial site investigations for Area A and Area B. The limits of these data have been identified in the associated reports.