PUBLIC HEALTH ASSESSMENT
NAVAL AIR STATION WHITING FIELD
MILTON, SANTA ROSA, FLORIDA
Naval Air Station (NAS) Whiting Field is a 2,560-acre installation devoted to training naval aviators. It is located in Santa Rosa County, in the northwest portion of the Florida panhandle, approximately 20 miles northeast of Pensacola and 8 miles north of Milton. Past handling and disposal of chemicals used at NAS Whiting Field, including solvents, paints, degreasers, oil, and fuels, resulted in releases to the environment, either due to accidental spills or leaks or to surface disposal or burial of these substances. Efforts to identify contamination at the installation began in 1985. Since then, 29 sites have been identified under the Department of Defense's Installation Restoration Program (IRP). An investigation of each has been completed, is underway, or is planned. An appropriate remedial alternative that is protective of human health will be selected for each IRP site. There are several plumes of trichloroethylene and its breakdown products, and of benzene, toluene, ethylbenzene, and xylenes (petroleum byproducts) within the installation. Contaminants are thought to be migrating off site in only one location, near the southeast corner of the installation.
In 1986, two of NAS Whiting Field's three water supply wells were closed because volatile organic compounds (VOCs) were detected in the wells at concentrations exceeding safe drinking water standards. Benzene concentrations exceeded the state drinking water standard in one well, and trichloroethylene concentrations exceeded the state and federal drinking water standards in the other. Each well reopened after a treatment system was installed to remove the contaminants. As a precautionary measure, a treatment system was also installed on the third water supply well. NAS Whiting Field was placed on the U.S. Environmental Protection Agency's National Priorities List on June 30, 1994, due to contamination detected at the installation, particularly groundwater contamination that had affected the on-site water supply.
The Agency for Toxic Substances and Disease Registry (ATSDR) visited the site in 1994 and 1999 to collect information about how people on and off site might be exposed to environmental contamination and to obtain environmental sampling results. During its review of available information, ATSDR identified the ways that people might be exposed to environmental contamination. Since groundwater is the source of drinking water both on and off site, the most widespread potential pathway for exposure is through drinking contaminated groundwater. Recreational users of Clear Creek and its floodplain may also come into contact with contaminated surface water, sediment, and fish. The exposure scenarios that ATSDR identified and evaluated are detailed below.
No Apparent Public Health Hazards
After evaluating available data, ATSDR concluded that past exposure to water from the NAS Whiting Field water distribution system poses no apparent public health hazard. No sampling data are available to assess the levels of contaminants, if any, in NAS Whiting Field drinking water prior to 1984. Limited sampling collected from the NAS Whiting Field distribution system in 1984 did not contain detectable concentrations of contaminants. However, levels of VOCs exceeding safe drinking water standards were detected during sampling of supply wells and the distribution system in 1985 and 1986. Use of the contaminated supply wells was suspended in 1986 until they were fitted with treatment systems. Because of the relatively low levels detected, and the short period of exposure, it is very unlikely that adverse health effects would result from exposure to the maximum levels of VOCs detected in the NAS Whiting Field drinking water. Levels of VOCs detected in more than one sample were several orders of magnitude lower (i.e., 1,000 to 100,000 times lower) than the lowest doses found to cause adverse health effects in animal studies. Thus, ATSDR concludes that it is unlikely that levels of VOCs were high enough to cause adverse health effects to NAS Whiting Field employees and on-site residents.
Exposure to off-site groundwater presents no apparent public health hazard because no one has or is expected to consume drinking water containing site-related contaminants. Groundwater contamination has only been found migrating beyond NAS Whiting Field boundaries near the southeast corner of the installation. In a water well survey, the U.S. Navy determined the locations of private wells near NAS Whiting Field. From this survey, the Navy found one well located in an area downgradient of on-site groundwater contamination, which might be subject to contamination. However, no VOCs were detected in tap water collected from this well. In addition, at the request of homeowners, two other private wells have been sampled. These samples did not contain any VOCs. To ensure that no exposures of health concern occur, ATSDR recommends that the U.S. Navy continue to fully delineate the extent of off-site groundwater contamination and develop and implement a plan to monitor any private wells in the path of contaminant migration and address any detected contamination.
Exposure to surface water, sediment, and fish in the Clear Creek floodplain poses no apparent public health hazard. Clear Creek is difficult to access and thought to infrequently be used for recreation. Furthermore, signs have been posted by the U.S. Navy to warn people of contaminants in the floodplain. Surface water and sediment contaminant levels are too low to cause adverse health effects. No fish tissue data have been identified by ATSDR. However, contaminants that might accumulate in fish were detected in sediment samples only sporadically. This suggests that the contaminants are unlikely to accumulate in fish to levels that would cause adverse health effects to people occasionally consuming the fish. Since exposure to Clear Creek and its floodplain pose no apparent public health hazard, ATSDR recommends that use of this area not be curtailed. The U.S. Navy is planning to conduct further sampling of the creek and floodplain to more fully characterize the contaminants present in the area and to ensure the future safety of this area.
No Public Health Hazard
Current and future consumption of on-site drinking water poses no public health hazard because any VOC contamination is removed by a treatment system at each supply well, water is mixed prior to distribution, and drinking water is monitored regularly to ensure that it meets federal and state safe drinking water standards. Thus, no exposure to contaminants at levels of health concern will occur. In addition, NAS Whiting Field is planning to remediate sources of groundwater contamination to the extent possible.
A summary of exposure scenarios identified at NAS Whiting Field is presented below.
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Exposure Hazard Summary Table--Naval Air Station Whiting Field |
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Exposure Scenario |
Time Frame |
Exposure? |
Public Health Hazard? * |
Actions Taken/ |
| Consumption of contaminated on-site drinking water | past current future |
yes no no |
no apparent no no |
• VOCs of concern were detected at concentrations
unlikely to cause adverse health effects • In 1986, after VOC contamination was detected, supply wells were closed until activated carbon adsorption filtration systems were installed • Monitoring of water supply wells is ongoing • Remedial actions are underway or planned to address some of the sources of groundwater contamination |
| Consumption of contaminated drinking water from off-site wells | past current future |
unlikely unlikely unlikely |
no apparent no apparent no apparent |
• A well survey was performed in 1995, and
efforts to identify any other private wells in use are ongoing • Tap water at a house served by a private well near site-related contamination was sampled and did not contain VOCs • Two private wells were sampled at the request of homeowners, and no VOCs were detected • ATSDR recommends that the full extent of the contamination near installation boundaries be delineated • If it appears that any private wells might be affected by groundwater contamination migrating from NAS Whiting Field, ATSDR recommends that the U.S. Navy develop and implement a plan for monitoring these wells and addressing any detected contamination |
| Contact with contaminated surface water, sediment, and/or fish in Clear Creek | past current future |
yes yes yes |
no apparent no apparent no apparent |
• Detected levels of contaminants are too
low to pose a health hazard • Signs warning of contamination in the floodplain have been posted in the vicinity • Based on the results of site investigations, an appropriate remedial alternative will be implemented, if needed • ATSDR recommends that recreational use of the Clear Creek area not be curtailed |
Naval Air Station (NAS) Whiting Field is located in the northwest portion of the Florida panhandle, in Santa Rosa County. It is approximately 20 miles northeast of Pensacola and roughly 8 miles from downtown Milton (see Figure 1). The mission of NAS Whiting Field is to train naval aviators in the use of basic instruments, in formation and tactical phases of fixed-wing, propeller-driven aircraft operation, and in the basic and advanced aspects of helicopter operation (ABB-ES 1998a; U.S. Navy 1995).
NAS Whiting Field currently encompasses approximately 2,560 acres and consists of two air fields separated by an industrial area. The air fields are known as North Field, which serves as the fixed-wing aircraft training base, and South Field, where helicopter training occurs. The industrial area contains facilities for industrial and administrative support, as well as military quarters (ABB-ES 1998a; U.S. Navy 1995). Land adjacent to the facility is primarily used for agriculture and forestry. However, within several miles of the facility (primarily to the southwest) are numerous residences and businesses associated with Milton (ABB-ES 1998a; NASWF 1999).
The facility was commissioned as Naval Auxiliary Air Station Whiting Field in 1943. During World War II, naval aviators were trained at the field. Subsequently, the facility was elevated to naval air station status and became the backbone of the Navy's flight training program. NAS Whiting Field has become known as the busiest naval air station in the world (U.S. Navy 1995).
The primary mission of the NAS Whiting Field has always been to train naval aviators, and various training squadrons have been stationed there over time. For example, the Navy's precision flying team, the Blue Angels, was stationed at NAS Whiting Field in 1949 and 1950. Helicopter squadrons have been active at the facility since 1974. Currently, NAS Whiting Field is home for the Training Air Wing Five, which includes fixed-wing squadrons VT-2, VT-3, and VT-6 and helicopter squadrons HT-8 and HT-18. Other groups are stationed at the field to provide support (ABB-ES 1998a; U.S. Navy 1995). There are 12 geographically separate installations associated with NAS Whiting Field. Known as Outlying Landing Fields, they range from 10 to 60 miles from the installation (Armed Forces. com, n.d).
The majority of contamination identified at NAS Whiting Field has resulted from the handling and disposal of products used at the facility over time, including solvents, paints, degreasers, oil, and fuels. Old landfills and disposal areas have also contributed to site-related contamination, as have accidental spills and leaks (U.S. Navy 1995).
Remedial and Regulatory History
In May 1985, an Initial Assessment Study of NAS Whiting Field was released. Available records, site reconnaissance, and interviews with long-standing and former employees indicated that most waste generated at the installation was disposed of on site until hazardous waste management programs and oil recycling programs were instituted in the 1970s. The report identified 16 areas (designated Site 1 through Site 16) where contaminants may have been used, stored, treated, or disposed of and concluded that further study of them was warranted (Envirodyne Engineers 1985; ABB-ES 1998a). In December 1985, two sites (termed Sites 17 and 18) were added to the list of areas warranting further study. Data regarding one site identified during the Initial Assessment Study, Site 5, were compiled in a 1985 report. This site, the Battery Acid Seepage Pit, had been the subject of a consent order issued by the Florida Department of Environmental Regulation, later renamed the Florida Department of Environmental Protection (FDEP) (ABB-ES 1998a). Soil and/or groundwater sampling at most of the remaining sites commenced in 1986 (Geraghty & Miller 1986).
On August 18, 1986, the state of Florida requested that one of the installation's water supply wells, known as South Well (Well W-S2), be shut down due the detection of benzene levels exceeding the state's drinking water standard of 1 part per billion (ppb). On September 25, 1986, the State requested that an additional well, known as West Well (Well W-W3), be shut down because the level of trichloroethylene in the water exceeded the state's drinking water standard of 3 ppb. Filtration systems were subsequently installed on the wells to reduce concentrations of volatile organic compounds (VOCs), including benzene and trichloroethylene, to levels below health concern (USEPA n.d.).
Because of the documented contamination of the installation and its water supply, the U. S. Environmental Protection Agency (USEPA) placed NAS Whiting Field on the National Priorities List, pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), on June 30, 1994.
In 1990, under the Department of Defense's Installation Restoration Program (IRP), a remedial investigation (RI) at NAS Whiting Field commenced to characterize the nature and extent of contamination at the 18 identified sites. During Phase I of the RI, five additional sites requiring study were identified. These sites were designated Sites 29(1) through 33 and were to be investigated during Phase II of the RI. The six separate locations comprising site 31 were later assigned the designations 31A through 31F (ABB-ES 1995b). Three sites meriting investigation that had been identified in July 1993 were added to the IRP in 1995 (Sites 35(2), 36, and 37). Contamination in these areas was characterized in 1996 and 1997 (ABB-ES 1998b). Site 38 was added to the IRP in 1996.
In 1993, during Phase II RI activities, four drums were found in the Clear Creek floodplain and subsequently removed. Reportedly, this was an isolated incident (ATSDR-DHAC 1995; NASWF 1999). The floodplain was sampled in 1993 and 1997 and was added to the list of IRP sites in 1997 (as Site 39), as was facility-wide groundwater (Site 40). (See Appendix A, which summarizes available information about identified sites and Figure 2.) Pesticide Storage Building 1485C may be added to the list of IRP sites if planned soil and groundwater sampling reveal contamination. The building, which was used for storage of maintenance equipment and pesticides, caught fire in the late 1980s (Tetra Tech, 2000). As a potential site, the area is known as Potential Source of Concern (PSC) 1485C.
In September 1999, a record of decision (ROD) for surface and subsurface soil contamination at Site 1 was issued. The remedial action selected is land use controls, which prohibit residential use of the site and require periodic site inspections, among other things. Activities involving limited human exposure to the site, such as recreation, industrial or commercial uses, or limited agriculture, will be allowed on site (HLA 1999a). A September 1999 ROD for surface and subsurface soil at Site 2 also calls for the adoption of land use controls (HLA 1999b).
RIs and/or feasibility studies (FS) at IRP sites numbered 3 and higher are ongoing. A pilot study to remove petroleum products from soil at Site 4 is underway (Martin 2000). Nine petroleum-contaminated sites have been investigated by NAS Whiting Field's Underground Storage Tank (UST) program. At seven of the sites, sampling did not indicate related groundwater contamination. Appropriate remediation, such as the removal of contaminated soil, is planned at the other two sites, a JP-5 release from a pipeline at the intersection of Hornet and Saratoga Streets and a release of aviation gasoline (AVGAS) from Tanks 1438 and 1439 (Holland 2000b).
In December 1994, the Agency for Toxic Substances and Disease Registry (ATSDR) conducted an initial site visit and met with representatives of NAS Whiting Field, the Naval Environmental Health Center, and other interested governmental agencies, including FDEP (ATSDR-DHAC 1995). After the site visit, ATSDR recommended that a private well survey be performed and potentially-impacted wells be sampled. The U.S. Navy conducted a well survey of private well use within 4 miles of NAS Whiting Field in 1995. During the site visit, warning signs clearly marking most IRP sites were observed (NEHC n.d.).
In June 1999, ATSDR conducted another site visit to gain an understanding of current site conditions and of the status of remedial actions, as well as to collect site-related documents and environmental data (NASWF 1999).
At the time of the 1990 U.S. Census, the total off-site population within one mile of the site was 1,371. Of these individuals, about 82% were white, 13% were black, and the others were of other racial origin. There were 166 children under the age of 6, 38 adults over the age of 65, and 334 females of reproductive age (15-44 years). (These numbers were calculated by ATSDR from 1990 U.S. Census data using an area-proportion spatial analysis technique.)
As of 1995, NAS Whiting Field employed approximately 3,800 military and civilian personnel. At that time, about 600 aviators were earning their wings at the facility each year (U.S. Navy 1995). The average tour of duty at NAS Whiting Field is 1 year, but aviators undergoing training at the installation may reside on site for up to 3 years (NASWF, 1999). An on-site housing facility known as the bachelors' quarters (BQ) typically houses from 100 to 300 military personnel on regular tours of duty (Brown & Root Environmental 1997). During the year ending in October 1999, the average daily residency of the BQ was 362 people (Durbin 2000). Just outside the main gate, there are 82 housing units available to NAS Whiting Field employees. This community, referred to as Magda Village, uses the installation's water supply (ATSDR-DHAC 1995). A larger housing development, called Whiting Pines, also served installation personnel and is located 7 miles south of the installation.
Milton is the largest incorporated municipality in Santa Rosa County. The site vicinity, in northern Santa Rosa County, is largely rural. Downtown Milton is approximately 6 miles southwest of NAS Whiting Field. Other nearby communities are East Milton (approximately five miles to the south), Point Baker (approximately 1.5 miles to the southwest), and Allentown (approximately 2 miles to the north). The 1990 U.S. Census reported 29,520 residents of Milton. According to the Navy, Santa Rosa County has experienced and is still experiencing significant population growth. The population of the county has grown from 55,988 in 1980 to over 90,259 (U.S Navy, 1995).
As of 1983, almost 65% of the county was forested, about 13% was used for agriculture, and only 4% was developed. The primary industries in the county as a whole are agriculture, U.S. Navy activities, manufacturing, forestry, oil, and tourism/recreation. Land to the northwest of NAS Whiting Field is primarily used for agriculture, land to the south and southwest is primarily residential or forested, and land surrounding the remaining borders of the facility is forested (Envirodyne Engineers 1985; U.S Navy, 1995).
Other military facilities in the vicinity are Pensacola NAS, located approximately 23 miles to the southwest, and Eglin Air Force Base, located approximately 10 miles to the southeast of NAS Whiting Field. Eglin Air Force Base is the largest military base in the nation and spans three counties on the Florida panhandle, including 10% of Santa Rosa County. The Blackwater River State Forest, occupying about 60,000 acres of land, is approximately 10 miles northeast of NAS Whiting Field (Envirodyne Engineers 1985).
Access to NAS Whiting Field is restricted to military personnel, civilian employees, and authorized visitors. The installation is surrounded by a perimeter fence. Signs posted on the fence warn that trespassing is not permitted. People entering the facility must pass through staffed entrance gates. Within installation boundaries, certain contaminated sites are fenced (NASWF 1999).
There are no schools at NAS Whiting Field, although there is an on-site child development center that opened in 1988 (NASWF 1999). The installation also supports a community center, which opened subsequently (Holland 2000b).
NAS Whiting Field is located on a plateau that slopes to the south. Elevations range from 150 feet to 190 feet above sea level. The land is well-drained; Clear Creek is to the west and south, and Big Coldwater Creek is to the east. The eastern floodplain of Clear Creek is within the boundaries of NAS Whiting Field, but outside of the fencing surrounding the installation (ATSDR-DHAC 1995; ABB-ES 1998a). Big Coldwater Creek is about 2 miles west of the installation boundary. Both creeks are tributaries to the Blackwater River, which feeds the Blackwater Bay, about 7 miles due south of NAS Whiting Field (U.S. Navy 1995). No drinking water intakes on Clear Creek, Big Coldwater Creek, or Blackwater Creek exist (ABB-ES 1998a).
Clear Creek and Big Coldwater Creek have been designated by FDEP as Class III surface waters, a designation applied to water bodies suitable for the propagation of fish and aquatic life and for recreational uses that involve body contact with the water. The Blackwater River is classified as an Outstanding Florida River, affording it recognition as a water body of exceptional recreational and ecological significance (ABB-ES 1998a).
When land was cleared for North and South Fields in the 1940s, concerns about the possibility of erosion led to the implementation of several soil conservation measures. Slope contouring and a system of concrete-lined drainage ditches were instituted to channel surface water runoff from runway, support, and industrial areas at NAS Whiting Field to either Clear Creek or Big Coldwater Creek. Five ditches run southwest from points on the west side of the facility to Clear Creek. From north to south, they are E Ditch, C Ditch, New A Ditch, New M Ditch, and New S Ditch. "New" ditches were reconstructed in the 1950s. Two ditches originating on the east side of the facility, P Ditch and Y Ditch, run east to a tributary of Big Coldwater Creek (ABB-ES 1998a; NASWF 1999).
Studies of hydrogeologic conditions at NAS Whiting Field indicate that some groundwater on the west side of the installation, flowing to the south or southwest, recharges Clear Creek. In addition, until April 1998, discharge of "secondary-treated" sewage effluent from the Sanitary Wastewater Treatment Plant at NAS Whiting Field, several hundred feet north of Site 31A, entered Clear Creek. Since April 1998, wastewater has been routed to the Milton wastewater treatment plant (ABB-ES 1993a; NASWF 1999).
Big Coldwater Creek, about 2 miles from the facility, is reportedly heavily used for recreation. However, this creek is not thought to be affected by NAS Whiting Field-related contamination. Clear Creek runs through the southwest corner of the installation. However, in this area, the creek is surrounded by dense vegetation, and few locations for public access exist. A small number of nearby residents are, however, thought to access the creek (NASWF 1999). Furthermore, there was a portion of NAS Whiting Field, at the southwest corner of the facility, that the Boy Scouts of America were permitted to use by the installation. Occasional Boy Scout use occurred from approximately 1987 to 1994. A fence separated the area used by the Boy Scouts from the remainder of the installation. Most Boy Scout activity is thought to have been restricted to a cleared area within a loop at the end of the access road to the camp. This area is about 1,000 feet from Clear Creek. The remainder of the 41-acre camp is forested (Gibson 2000).
Quality Assurance and Quality Control
In preparing this public health assessment (PHA), ATSDR reviewed and evaluated information provided in the referenced documents. Documents prepared for the CERCLA and Resource Conservation and Recovery Act programs must meet specific standards for adequate quality assurance and control measures for chain-of-custody procedures, laboratory procedures, and data reporting. The environmental data presented in this PHA are from U.S. Navy reports, including investigations of the IRP sites, as well as from information provided by FDEP and NAS Whiting Field on samples collected from the NAS Whiting Field drinking water supply system and from private wells. Based on our evaluation, ATSDR determined that the quality of environmental data available in site-related documents is adequate to make public health decisions.
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