• Home
• About ATSDR
• Press Room
• A-Z Index
• Glossary
• Employment
• Contact Us
• CDC

ATSDR en Español

Search:

Skip directly to: content | left navigation | search

---

Find a Publication

1. ATSDR > Public Health Assessments & Consultations

Tinker Air Force Base (Tinker), an active industrial complex for overhauling, modifying, and repairing aircraft, was activated in 1942. The 4,277 acre base is in central Oklahoma in the southeast section of Oklahoma City and Midwest City. The base is surrounded by residential and commercial property.

In May, 1988, The Agency for Toxic Substances and Disease Registry (ATSDR) issued a public health assessment pertaining to Tinker. A copy of that public health assessment appears as an attachment to this document. The public health assessment addressed concerns related to contamination at Building 3001, the National Priorities List site at Tinker. The health assessment also addressed, to a lesser extent, contamination of Soldier Creek. Since the release of the public health assessment, new public health concerns information and environmental data have become available that warrant an addendum to the health assessment. The contents and conclusions in this addendum supersede those in the 1988 Tinker Air Force Base Public Health Assessment.

Groundwater

Off-base private wells
Current and Future Exposures: Potential Public Health Hazard
Most residences were connected to the municipal water system in 1993-1994. However, hookups have been refused by some residents with contaminated wells. As of November 1995, 12 wells were not plugged. It is not known if all 12 wells are contaminated at levels that pose a public health hazard or if people are using the well water for potable purposes. Construction of new wells in the area northeast of Tinker is prohibited. Since groundwater remediation is incomplete, the potential exist for contamination to migrate to the 12 unplugged wells if they are near sources of groundwater contamination. Thus, current and future exposures are a potential public health hazard.
Past Exposures: Public Health Hazard
In the past, people were exposed to volatile organic compounds (VOCs) in contaminated private residential wells in the area northeast of Tinker. Contamination levels that may increase the risk of developing cancer after prolonged exposure were detected in several (6-8) of these wells. However, it is not known how long the wells were contaminated. The residences with well contamination above the Environmental Protection Agency's Maximum Contaminant Levels were supplied bottled water by the Air Force the same year contamination was detected (1990). A contamination source for the private wells still has not been identified.

Base Supply Wells

Current Exposures: No Public Health Hazard
Currently the base supply wells in use are in compliance with the Safe Drinking Water Act; and no one using base water is being exposed to contaminant levels that pose a health hazard.
Past Exposures: Public Health Hazard
Contamination was detected in base supply wells 18 and 19 at levels that would have posed a public health hazard if people were exposed directly to those concentrations. However, the contaminant concentrations that people were exposed to are unknown but are expected to be less than those in the contaminated base wells. Water from several wells enter the base water distribution system and is combined in holding tanks. Therefore, water from contaminated wells was diluted by uncontaminated water from other base wells. However, because trichloroethylene (TCE) concentrations reached as high as 1642 parts per billion (ppb) in well 18, it is likely that people were exposed to concentrations of TCE above the maximum contaminant level (MCL) of 5 ppb, even with dilution. The Air Force removed the contaminated wells from service permanently the same year (1983) contamination was detected.

Air

Current Exposures: No Apparent Public Health Hazard
ATSDR concluded that current ambient air emissions (based on the 1993 air monitoring study) from the Industrial Wastewater Treatment Plant (IWTP) pose no apparent public health hazard. However, the ambient air concentrations of hydrogen sulfide were determined to be at levels that may be perceived as a nuisance to the nearby community. Since the study, the Air Force has made and continues to make numerous upgrades to the IWTP unit processes to reduce air emissions.
Past Exposures: Indeterminate Public Health Hazard
ATSDR was unable to evaluate past exposure to the IWTP air emissions because appropriate environmental data were not available. Past emissions may have been greater than the concentrations detected in the 1993 IWTP air study because process modifications to reduce emissions had already been implemented. To help determine if exposures to past air contamination may have caused health problems, ATSDR's Division of Health Studies is in the preliminary stages of conducting a review of health statistics and cancer mortality data.

Creek Surface Water and Sediments

Current and Past Exposures: No Apparent Public Health Hazard
Exposures to surface water and sediment in East Soldier, West Soldier, Elm, Kuhlman, and Crutcho Creeks pose no apparent public health hazard. However, ATSDR recommends that children not use East Soldier Creek as a frequent play area because the base is permitted to discharge treated wastewater from the IWTP to the creek and an atypical/unexpected release could pose a health hazard if people were exposed. The Air Force plans to begin discharging wastewater to the Oklahoma City Regional Water District System by the end of March 1996, however, they will still maintain their permit for discharge to East Soldier Creek.

ATSDR's Division of Health Education will provide fact sheets regarding IWTP discharges into East Soldier Creek. Fact sheets should be available by Spring 1996.

BACKGROUND

Site Description and History

In May 1988, ATSDR issued a public health assessment addressing the contamination associated with the Building 3001 complex at Tinker Air Force Base (Tinker). The Public Health Assessment is included in Appendix A. That document addressed groundwater and soil contamination under Building 3001 and sediment contamination in East and West Soldier Creeks to a limited degree. Since the public health assessment was issued, additional information has been provided to ATSDR concerning these sites. Information is also available for other sites listed on Tinker's Installation Restoration Program (IRP). Therefore, this addendum has been provided to update the previous public health assessment. New information included in this addendum is from site-specific documents and information provided by state and local officials and area citizens. The contents and conclusions in this addendum supersede those in the 1988 Public Health Assessment.

Tinker was activated in March 1942. The base is a major industrial complex for overhauling, modifying, and repairing military aircraft engines and accessory items. Tinker is the home of the Oklahoma City Air Logistics Center for the U.S. Air Force. The 4,277 acre base is in central Oklahoma in the southeast section of metropolitan Oklahoma City and adjacent with Midwest City (Figure 1). The base is surrounded by residential and commercial development to the north, west, and east, with industrial and commercial development to the south.

The IRP includes 36 sites including one National Priorities List (NPL) site, Building 3001 with its several operable units. Figure 2 shows the locations of all sites on the IRP agenda, including the NPL sites. Available information concerning contamination is discussed in the "On-Base Contamination" section of this document.

Descriptions of the IRP/NPL sites follow: ¹

The public health evaluation of Tinker determined that 12 of the 36 IRP/NPL sites are potential sources and/or areas of contamination that have public health significance (i.e., each of these sites have or may contribute to contamination of environmental media that people come in contact with). These 12 sites are sites 1, 2, 4-9, 14, 15, 30, and 31. The environmental media of concern include private and base supply wells, surface water and sediments in the creeks associated with the base, and air emitted from the IWTP.

Figure 1. Site Vicinity, Tinker Air Force Base

Figure 2.

Site 1--Building 3001

Building 3001 occupies approximately 50 acres and houses an industrial complex used in the overhaul and modification of aircraft. All phases of aircraft disassembly, engine overhaul, inspection, plating, testing, repair, and reassembly are conducted within Building 3001. Before the mid-1970s, industrial wastes were stored in concrete or steel-lined pits at various locations around and inside Building 3001. In the early 1970's pits were replaced with degreasing equipment.² Also, some solvents and wastewaters were drained to the storm drain system in the building due to improper tie-in connections between industrial waste lines and storm drains. In 1987, Building 3001 was placed on the NPL. Numerous cross-connections to the storm water sewer were identified in 1989 and have been eliminated.^3,4 By fall 1993, the Air Force had replaced over half of the industrial waste lines with a double walled system.⁵ The replacement of the remaining industrial wastewater lines is progressing at this time.

The past activities within Building 3001 have resulted in contamination of the on-base groundwater with chlorinated solvents and heavy metals. A Record of Decision (ROD) was signed August 1990 for Building 3001.¹ The ROD includes provision for a groundwater treatment system. This system includes 33 extraction and containment wells, 5 horizontal wells and 28 vertical wells. Construction began on the five horizontal wells in October 1992 and was completed in January 1993.⁶ These wells are primarily for extraction of contamination below Building 3001. The vertical wells are located around Building 3001 and are used primarily for containment of contamination. The Air Force began intermittent pumping of this system in February 1993. The wells were pumped continuously beginning August 1994.⁶

Site 2--Drinking Water Wells 18 and 19

Wells 18 and 19 were base drinking water supply wells. These wells were removed from service in 1984 after trichloroethylene (TCE) and tetrachloroethylene (PCE) were detected in samples drawn at the wellhead. Both wells were plugged in September 1986. No further response action is planned.⁷ Past activities within Building 3001 resulted in contamination of the groundwater with chlorinated solvents and heavy metals. Wells 18 and 19 were inside Building 3001 near the area of maximum groundwater contamination.

Site 3--Pit Q-51

Pit Q-51 was inside Building 3001. It was a 8 x 10 x 20 feet concrete-lined pit. Pit Q-51 was used from the 1940s to the 1970s to hold industrial solvents and wastewater from industrial operations. The pit contained approximately 45 gallons of liquid; contaminants detected included 42 ppm TCE, 3 ppm cadmium, 4 ppm chromium, and 22 ppm lead.^8,9 The pit showed no signs of leakage into the subsurface. The contents of the pit were removed and the pit was cleaned, backfilled with sand, and capped in 1991.⁹ The site cleanup was coordinated with the Oklahoma State Department of Health and the U.S. Environmental Protection Agency (EPA), Region VI.⁹

Site 4--North Fuel Area

This site is at the northwest corner of Building 3001 and covers approximately one acre. Site 4 is surrounded by an asphalt and concrete parking lot. The area is about 1000 feet east of West Soldier Creek and 1650 feet northwest the nearest on-base water supply well, WS-15. Five underground storage tanks were installed at this site between 1943 and 1963. Tank 3404, a 235,000 gallon heating oil tank, is known to be the main source of contamination at the site.¹⁰ Fuel oil is the primary hazard at the site and has been released over several decades.¹¹ Appreciable soil contamination has not been discovered at the site.¹¹ Forty-three monitoring wells were installed at this site between 1985 and 1993 to investigate subsurface contamination.

Site 5 - Soldier Creek

Soldier Creek Site was placed on the NPL July 22, 1987.¹² The Soldier Creek Site includes Soldier Creek and its tributaries (East and West Soldier Creek and tributaries A and B) and any area underlying or adjacent to the waterway that may be contaminated by the migration of contaminants from Tinker (Figure 3). Soldier Creek is primarily east of the base and flows north from its headwaters just north of Southeast 59th Street. It joins Crutcho Creek approximately six miles downstream. West Soldier Creek is the tributary that originates on the west side of Building 3001. East Soldier Creek is the tributary which flows along the east side of Building 3001 and past the Industrial Wastewater Treatment Plant (IWTP).

The primary sources of contamination at Tinker include leaks from on-base storage tanks and pits, discharge from industrial outfalls (cross connections corrected in 1990), contaminant spills, and runoff from runways and industrial facilities.¹² Soldier Creek and its tributaries receive surface runoff from an area consisting of approximately 9,000 acres which includes the IWTP, Building 3001, and North and Southwest Fuel Areas. East and West Soldier Creek receive discharges or runoff directly from Tinker. East Soldier Creek receives discharge directly from the IWTP.

Figure 3. Phase I and Phase II Sampling Locations for Soldier Creek, Tinker AFB.

Site 6--IWTP/Sewage Treatment Plant Soil
Site 7--IWTP Groundwater

Industrial wastewater used at the base is treated at the IWTP and then discharged to East Soldier Creek. The groundwater under the treatment plant has been determined to contain contaminants similar to those found at Building 3001.¹³ Eleven groups (16 tanks total) of concrete tanks used for processing were removed July-December 1992.⁹ One group of tanks contained industrial wastewater containing cyanides. Another set of tanks contained wastewater with chromium and one tank held wastewater with phenols. Two groups of tanks were used as chemicals addition tanks for the combined waste stream and six groups of tanks were used to adjust the pH of the combined waste stream.⁹ Soils under two of the groups of tanks contained contaminants, some of which were also found in the groundwater.¹³ These sites are currently under evaluation.

Site 8--Southwest Tanks Area

The Southwest Tanks Site consists of 17 abandoned fuel and solvent tanks. The site covers about 2.5 acres and is southwest of Buildings 3001 and 3108. Records indicate that the tanks have held gasoline, lubricating oil, naphtha, Stoddard solvent, JP-1 (jet fuel) and PD 680 solvent since their installation in the 1940's. Six of the seventeen tanks were removed. Three of the seventeen tanks were closed in-place. The remaining tank and vault (with seven tanks) are being investigated and will be scheduled for closure following completion of the ongoing investigations.

Several Innovative Technology Demonstration projects (in situ sensors, soil gas monitoring, soil fracturing and bioventing) are currently being used at the Southwest Tanks site. Toluene, benzene, xylene, ethylbenzene, DCE and TCE have been detected in the groundwater or soil in this area. Contamination may have resulted from past leaks or spills from the tanks.²

Site 9--Fuel Farm

The original Fuel Farm consisted of five 18,000-gallon underground storage tanks (USTs) and twenty 25,000-gallon USTs. Motor fuel, aviation gasoline, and JP-4 were stored in the tanks. The USTs were drained and replaced with above-ground storage tanks in 1988. In 1979 and 1980, two spills of 6,000 and 10,000 gallons occurred. Investigations in 1985, 1987, and 1988 detected fuel-related contaminants in the soil and groundwater at the site. Currently, the site is being investigated to determine the amount of contamination in the soil and the extent of groundwater contamination.^6,7

Site 10--Four Fuel Sites

These sites are in two distinct locations: near Building 201 and near Building 214. Sites near Building 201 are the South Alcove Site, West Alcove Site, and North Side Site. The site near Building 214 is the Southwest Corner Site. Fuels, primarily diesel fuel, and solvents were stored in underground storage tanks in these areas. Leaks from the underground storage tanks and/or lines resulted in contamination of soils and groundwater.¹⁴

The South Alcove Site is south of site 22. The abandoned underground storage tank is apparently under a pump and fill pad. The Phase I RI reports that the Air Force identified the tank as Tank 204, a 500 gallon steel tank used to store solvents from 1944 until 1972, when it was abandoned. Equipment left near the area suggests that the tank may have also been used for hydraulic fluid.¹⁴

The West Alcove Site lies within a narrow, grass covered alcove west of Building 201. Nothing is present at ground surface to indicate the presence of an underground storage tank. The Phase I RI describes the tank as a 500 gallon diesel tank. Air Force documents describe the tank as #201A, a 500 gallon steel tank constructed in 1944 and abandoned in 1975. The tank reportedly stored fuel for an emergency generator. No record of tank removal has been found by the Air Force.

The North Side Site is in a concrete, paved, fenced, hazardous materials storage area on the north side of Building 201. When the Phase I investigation was performed, the tank was reported to be filled with liquid that may have been water. The Air Force listed the tank as a 1500 gallon steel tank constructed in 1942 for solvent storage.² The Phase I RI reports that workers said the tank may have been used for sewage storage rather than waste solvents and that another tank may be in the vicinity. Chemical analysis of the water in the tank indicated that the tank likely contained some solvents.¹⁴

The Southwest Corner Site is at the test bay portion of Building 214. The Air Force lists the tank as #214, constructed in 1944 for the collection of unspecified wastes from the engine test bays. The tank was abandoned in 1987.¹⁴

Sites 11, 12, and 13--Fire Training Areas 1, 2, and 4

Fuel oils mixed with other wastes were burned in unlined pits at these sites by the Tinker Fire Department. Some of the areas have been tentatively identified through old records and aerial photographs.

Site 11, Fire Training Area 1, was used from 1959 to 1962. The site is on the west side of Tinker and is bounded by Crutcho Creek to the southwest, Patrol Road to the east, and the old municipal sewage treatment plant site to the north. The area is circular with a diameter of approximately 125 feet. No documents or records are available to identify the chemicals used during training. The remedial investigation was completed in May 1992.

Site 12, Fire Training Area 2, was used between 1962 and 1966. The site is on the southern portion of Tinker, northwest of the control tower, and near Crutcho Creek. No records were found to identify the actual frequency of use and amount of fuel burned at the site.¹⁵ The site is a level grassy area with no visible signs of use as a fire training area. No significant contamination was detected at the site.¹⁶

Site 13, Fire Training Area 4, was suspected as a fire training area. Investigations confirmed that this area was not used as a fire training area.⁶

Site 14--Area A Fuel Station (POL Area "A")

Area A Fuel Station is centrally located along the north boundary of the base at the northeast corner of the 5th Street and E Avenue intersection. The site was the base's service station for military vehicles from 1942 until 1990.¹⁷ Leaded and unleaded gasoline and diesel fuel were stored in four underground storage tanks. Two of the tanks, both with 12,000 gallon capacity, were installed in 1942 and suspected of leaking in 1978. The tanks were emptied, steam cleaned, and taken out of service in May, 1978.¹⁷ The other two tanks were installed in 1975; one leaked in 1982 and was replaced. The station ceased operation in October, 1990.¹⁷

A pumping system for the recovery of free fuel product was installed in 1991. The main components of this system are recovery wells, recovery pumps and controls, an oil/water separator, and an air stripper. Recovered fluids are processed through the oil/water separator. The effluent from the separator is then treated by the air stripper to decrease the concentration of dissolved fuel components prior to discharge to the treatment system.¹⁷ Samples of water from the separator discharge and the treated water effluent will be sampled monthly for oil and grease, BTEX (benzene, toluene, ethylbenzene, and xylene), and total lead content. The system will be operated until the floating product has been recovered.

Site 15--3700 Fuel Yard (POL Area "C")

Site 15 is in the east central part of the base. The site, an aviation fuel storage depot in the mid-1950s, was next to a railroad spur to facilitate fuel delivery. It contained six 25,000 gallon underground storage tanks, which were removed in 1991. About 1,500 cubic feet of backfill material contaminated with fuel was also removed.¹⁸ The excavation was backfilled with uncontaminated sand and the surface of the site was restored. JP-4 fuel is now delivered to the site via tanker truck where it is off-loaded to two surface storage tanks.¹⁸

Sites 16, 17, and 19-Landfills 1, 2, and 4

These sites, operated between 1942 and 1968, are on about 50 acres southwest of Reserve Road. The landfills accepted general refuse, industrial wastes, and petroleum products. Wastes were buried in trenches at the sites. Groundwater contamination has been confirmed to be migrating from the landfills. Drainage from the landfills is toward Crutcho Creek. Landfill 1 was capped in April 1991.

Site 18--Landfill 3

Landfill 3 is in the same area as Landfills 1, 2, and 4. The south end of the landfill had a sludge dump area which operated between 1961 and 1968 and reportedly received waste oils and liquids from Building 3001 and waste fuels and sludge from the Petroleum Oil Lubricant Facility.¹⁹ There are four trench holes on the landfill outside the sludge dump area. The three monitoring wells adjacent to Landfill 3 did not have a floating free product layer in January 1989.¹⁹ The landfill was capped in 1992.

Site 20--Landfill 5

Site 20 is at the corner of Tower Road and Patrol Road. This landfill, approximately 6 acres, was used as a disposal area for general refuse and possibly some industrial wastes from 1968 to 1970.

Studies indicate that contaminant migration is minimal.²⁰ A clay cap was installed on the landfill in the spring of 1990.⁶

Site 21--Landfill 6

Landfill 6 is off-base, southeast of Tinker. The landfill contains approximately 500,000 cubic yards of general refuse with some industrial wastes. The landfill operated between 1970 and 1979. Contamination has been detected in monitoring wells on the eastern, southern, and western perimeters of the site. Three monitoring wells were installed on the northern boundary of the landfill in 1984.²¹ This landfill was capped in January 1986.⁶ Approximately five acres of this landfill was damaged by off-road vehicles. In 1991, the damaged portion was recapped, monitoring wells were installed on the northern perimeter, and the site was fenced.²²

Sites 22-26--Radioactive Waste Disposal Sites

The past and present industrial activities have utilized many different types of radiological materials in the construction and repair of aircraft. Until 1951 radioactive waste considered to be of significant nature was sent to the Canadian Radium and Uranium Corporation in Mt. Kisco, New York. From 1951 until the 1960s radiological waste that was considered insignificant was disposed in the landfills in the southwest portion of the base.²³

Site 22, Radioactive Waste Site 201S, is adjacent to the south side of Building 201. The site is marked with a concrete monument and is posted. A survey of the site indicates that there is radium-226 in the top 1-2 feet of soil and that there are no buried radioactive objects at the site. A radium paint room in Building 201 in the 1950s may be the source of this contamination. Approximately 45 cubic yards of soil is contaminated with radium-226.⁹

Site 23, Radioactive Waste Site 1022E is northwest of site 18 and southwest of the Supernatant Pond. The site was identified through a records search conducted in 1989 and through interviews of base personnel conducted in 1981 and 1982. The site was excavated July 8-12, 1991. The site was excavated to the depth required to resolve anomalies and to reach undisturbed soils.^23,24 Disposal of contaminated soil has been completed by Tinker through their Defense Reutilization and Marketing Office (DRMO). All of the soils excavated were below the site release limit based on 10 mrem/yr above background. The detected activity was also below the EPA standard of < 5 pCi/g above 15 cm depth. The cap for Landfill 3 extends over Site 23.⁶

Site 24, Radioactive Waste Site 1030W, is within Landfill 2 (site 17) on the south end of the base. A tributary of Crutcho Creek flows through the site. The area is adjacent to a picnic area and was fenced in 1991.²⁵

The site was used to burn and bury radium dial waste (rags and solvents) in the 1950s. In the early 1970s, Pistol Pond was constructed on top of Landfill 2 and reportedly covered the site.²⁵ The pond was drained in 1986. The 1988 survey of the approximate site location identified no elevated readings. However, as a result of a surface survey (1990) and a intrusive survey (1991) a removal action was initiated in 1992. Approximately 920 cubic yards of radium contaminated soil were removed (1993) and taken to Envirocare in Utah for disposal. It is estimated that 420 cubic yards of contaminated soil still exist at the site. Following heavy rainfalls, water samples were taken (May 24, 1993) from the tributary to Crutcho Creek; one upstream, one downstream, and one on-site. No elevated levels of radium-226 were detected.⁹ Picnic tables in the area were removed in June 1993. The picnic tables were sampled and no radiological contamination was detected.⁹

Site 25, Radioactive Waste Site 62598, is north of Crutcho Creek and south of Facility 1025. The site is marked with a concrete monument and a radiation warning sign. The site reportedly contained a lead still (vault) containing radium paint solids. The Record Search report states that one Air Force document indicated that the waste had been removed at the site, but no records were located to confirm the removal.²³ No elevated gamma radiation levels were reported in the 1990 Phase II investigation, but some subsurface anomalies were detected during the geophysical survey.²³ Soil was excavated to the depth required to resolve the anomalies and to reach native soils. No waste or contaminants of any kind were found at the site during excavation. All soils removed were below the release limits for organics and metals and the 10 mrem/yr Total Effective Dose Equivalent. The detected activity was also below the EPA standard, < 5 pCi/g above 15 cm depth.

Site 26, Radioactive Waste Site 4000 is at a tributary of Elm Creek near Douglas Boulevard and 59th Street. The site is not physically marked as a suspected radioactive waste disposal site (). The 1989 Records Report states that a base employee remembers burying engine stader cases in a ravine on the eastern side of an Elm Creek tributary. The engine cases were marked as radioactive and indicated they contained thorium. The 1990 Phase II radiological and geophysical survey found no radioactive waste disposal on the site.^24,9

Site 27--Industrial Waste Pit 1

Site 27 is in the south central portion of the base, southwest of Building 2121. This shallow, unlined pit was used from 1947 to 1958 to receive industrial wastes streams from various aircraft plating and maintenance facilities. The pit was closed in 1958 by filling it with soil and grading it. Investigations of the site were conducted from 1982-1983, and the RI was issued in August, 1991. Metals were detected in both soil and groundwater samples, however the results for the one soil sample were in the low end of the detection range and the metal concentrations in groundwater were below the maximum contaminant levels (MCLs).²⁶ The RI concludes that no further action is required at the site.²⁶

Site 28--Industrial Waste Pit 2

This pit was used to bury industrial wastes including oils, cyanides, chromates, and acids from 1958 when Industrial Waste Pit 1 was closed until the waste treatment plant was built in 1963.²⁷ The pit was filled and graded in 1965. The site was investigated in 1984 by Radian Corporation at the request of the Air Force.²⁷ Minor groundwater contamination was reported, but the document did not specify the types of contaminants or their concentrations found at that time. Groundwater sampling conducted from June 1989 to April 1990 revealed that no significant contamination had migrated from this site into the perched water zone or top-of-regional zone. The final decision document for this site states that no further action is necessary.²⁸ However, the perimeter wells (MWs 80-82) will continue to be monitored on an annual basis for any possible migration of contaminants.

Site 29--Supernatant Pond

This site covers approximately 25,000 square feet and is directly east of Fire Training Area 1 along Air Depot Blvd. The site appears on Tinker base maps in 1954. The unlined pond was used as an impoundment for sewage effluent from the 1950s to the 1960s until the sewage treatment plant was constructed.²⁹ The pond continued to be used for disposal of liquid wastes until 1984. Those wastes reportedly contained petroleum hydrocarbon sludge, solvents, and cyanide-contaminated liquids.²⁹ The pond overflowed periodically during rain storms, and the overflow entered Crutcho Creek. The pond was filled with soil in 1984. Based on the outcomes of the 1991 RI and the Risk Assessment (RA), it was determined that the site did not pose an immediate threat to human health or the environment.³⁰ Because of this, the limited site size, and the extent of contamination, the Supernatant Pond was selected for demonstrating the innovative technology of soil solidification/stabilization.³⁰ The demonstration project began in June 1992 and the soils were solidified and stabilized in place.

Sites 30 and 31--Crutcho and Kuhlman Creeks

Crutcho Creek originates south of Tinker and flows northward through the base to the North Canadian River. Kuhlman Creek is a tributary of Crutcho Creek and originates in the north area of the base. These two creeks receive runoff, drainage from some base industries, and groundwater discharge from various IRP sites. Baseline field activities were conducted in July and October 1991. Confirmation data collection was confined to base boundaries and was performed in February and May 1992. The RI was issued in October 1992 and the Final Decision Document was signed in September 1993. These two documents state that known conditions at these creeks pose no current or potential threat to human health or the environment.^31,32 A long-term monitoring program is planned for these sites.

Site 32--Facility 1123

Building 1123 was part of the Directorate of Distribution storage area near the south boundary of the base. Hazardous material drums containing flammable materials and solvents, such as methyl ethyl ketone and tetrachloroethylene, were stored in this building.³³ Spills are reported to have occurred and in 1984 to 1985 the dirt floor was covered with a concrete floor. During the installation of the new floor, about six inches of soil were removed and replaced. The building was removed for the construction of the Navy runway approach project. In March 1990, eight soil samples from this site were analyzed for metals, volatiles, and semi-volatiles and none exceeded EPA guidelines.³³ The Air Force decided on a "no action" decision for this site and it was removed from the IRP in June 1991.³³

Site 33--Multiple Creeks

This site was deleted as an active IRP site in 1991 and is now divided into two sites, Crutcho Creek and Kuhlman/Elm Creeks.³⁴

Site 34--Bonnewell

Bonnewell was deleted as an active IRP site in 1991 and is being addressed as part of the IWTP/Soldier Creek Groundwater Operable Unit.³⁴

Site 35--Discharge Ditch - Building 17

Building 17 is in the north central portion of Tinker and was built in the 1950s as a paint shop and remains in that capacity. Over the years, chemicals associated with painting such as solvents were stored outside in a fenced, paved area, approximately 50 by 60 feet, next to Building 17. This area drains to a storm water culvert. The site was discovered in May 1989. Chemicals have not been stored at this site since that time.³⁵ Based on visual indication of contamination and employee interviews, the Air Force decided to remove the discolored pavement and contaminated soil underneath. Samples were taken from the removed material and no contaminants were detected.³⁵ Following completion of the investigation, this site was removed from the IRP in September 1992.

Site 36--Purge Facility (Waste Fuel Dump Site)

This site covers an area about 500 feet in an east-west direction by 600 feet in a north-south direction. It is in the southeast corner of Tinker approximately 400 feet south of Building 2121 along 59th Street. This facility was in operation from 1975 to 1990. Waste fuels (JP-4 and JP-5) from aircraft in the maintenance facility were drained and then transported by truck to this site for disposal. Numerous spills allegedly occurred in this area during its operation.³⁶ Surface runoff flows from the Purge Facility in a southwesterly direction to an unnamed intermittent stream that flows to the northwest towards Crutcho Creek. In 1990, this facility underwent modifications which included a new concrete pad and a new bunker with spill-containment protection. From 1990 through 1992, three subsurface investigations were conducted to delineate the hydrocarbon contamination. The second investigation identified two areas of contamination at this site: one area is around the old bunker site and the other lies about 15 feet west of the first area. ³⁶ The Air Force has no plans for interim measures at this site and none are currently required.

Site Visit

On May 13-16, 1991, ATSDR staff conducted a site visit to Tinker Air Force Base. During the site visit, ATSDR attended a base-sponsored Technical Review Committee (TRC) meeting. ATSDR met with state and local agencies to discuss their environmental sampling data and concerns about the installation. ATSDR also accompanied local health department representatives into the off-base communities while the county representative collected private well water samples for analyses. ATSDR gathered community concerns from local citizens at that time.

On May 4-6, 1992, ATSDR staff met with representatives of Tinker Air Force Base, Wright-Patterson Air Force Base, and Brooks Air Force Base at Tinker to collect data generated since the site visit the previous year. ATSDR learned that new information on many of the sites was available and would be provided. Sites were re-visited to clarify questions about previous observations. ATSDR also met with Oklahoma State Health Department representatives for clarification of data and to request information about new concerns expressed since the last site visit.

On May 19-20, 1993, ATSDR staff again met with Tinker officials to review new environmental sampling data and plans. Several of the hazardous waste sites were toured. Public availability meetings were held in the local community to gather community concerns.

On November 1-3, 1994, ATSDR met with Tinker officials, Oklahoma Department of Environmental Quality, and Oklahoma City/County Health Department to discuss issues related to the public health assessment. ATSDR held a public meeting on November 3, 1994 to update the community on ATSDR activities at the site.

During the site visits, ATSDR toured the sites that were determined to be of concern. Access to many of the sites toured was not restricted to base personnel and residents. Observations of the sites toured are discussed below:

Site 1--Building 3001

ATSDR toured the work areas of Building 3001. Both forced and natural ventilation are used in the building. Work areas include degreasing operations, plating operations, painting operations, aircraft hangers, and other activities involving the refurbishing of aircraft and aircraft engines.

Site 4--North Fuel Area

ATSDR observed progress on remediation activities during the 1992 site visit. The remediation plan is described in documents issued in March, 1992. At the time of the site visit, the tank top was off for sampling and cleaning.

Site 5--Soldier Creek

The creek flows through neighborhoods and trailer parks where children were seen in yards. During the May 1993 site visit, ATSDR staff walked the bank of East Soldier Creek from Douglas Boulevard past Evergreen Trailer Park. Most of the area had limited access due to the heavy vegetation along the creek. However, along the creek just behind the Evergreen Trailer Park the banks were relatively clear of vegetation. The area had trails along the creek.

Sites 6 and 7--Industrial Wastewater Treatment Plant

In 1992 and 1993, ATSDR toured the IWTP area accompanied by Tinker representatives. Batch processing tanks were being removed in 1992 and the removal had been completed by the 1993 site visit. The facility is about 200 yards south of a residential community and the future Child Development Center. Wastewater discharges to Soldier Creek that flows on the east side of the facility.

Sites 16-19 and 24--Landfills 1-4 and Radiation Waste Site 1030W

Landfill 2 is adjacent to a family camp ground, a recreational pond, and play area. The recreational pond that is part of the camp ground is bermed. Drainage from the site does not appear to flow in the direction of this pond. Radiation Waste Site 1030W is in the northwest portion of Landfill 2 at an area that was Pistol Pond before the pond was drained. The radiation waste site was unrestricted at ATSDR's initial site visit, but was fenced in 1992. During the May 1993 site visit, a couple of hundred shipping containers and approximately 75 drums containing excavated soil were in a roped off area. The radiation waste site is near one of the former picnic areas.

Crutcho Creek flows along the eastern borders of Landfills 1 and 3. Drainage from these landfills flows toward the creek. A cap was under construction at Landfill 3 in 1991 and was complete at the 1992 visit.

Site 21--Landfill 6

Landfill 6 is on 59th Street 1/2 mile ease of Douglas Boulevard near a communications and radar facility owned by Tinker. A depression, which acts as a drainage ditch, transects the site in a north/south direction. County potable water lines were being installed along the roadside adjacent to the northern border of the site in 1991. At the time of the site visit in 1991, monitoring wells were on all sides of the site. At the time of the site visit in 1992, the landfill cap had been repaired and a fence had been installed around the landfill.

Sites 11 and 29--Fire Training Area 1 and Supernatant Pond

During the 1991 site visit, piezometers and other signs of site investigations were present on both sites. In 1992, site investigations were continuing.

Site 28--Industrial Waste Pit 2

Industrial Waste Pit 2 is fenced. Drainage is toward ditches which carry runoff into Crutcho Creek and Elm Creek.

Site 30--Crutcho Creek

ATSDR observed two areas of Crutcho Creek: an area that receives drainage and runoff from Landfill 3 (Site 18) and the Supernatant Pond (Site 29) and an area that flows near a recreational area near the golf course. Access to the area receiving runoff is not restricted; however, the area is not likely frequented by base residents because of the proximity to the landfills. At the area near the golf course, the creek is separated from the recreational area by a chainlink fence. A foot bridge provides access from one side of the creek to the other. A large number of at least two species of turtles were swimming in this area of the creek.

The creek flows through the base housing area in the western section of the base. The creek near the school is posted "Playing in Creek Prohibited".⁵ The posting is due to potential physical hazards.³⁷

Demographics, Land Use, and Natural Resource Use

Demographics

Demographic information is included in the public health assessment to characterize people (by number, race, ethnicity, gender, etc.) potentially exposed to site contaminants. Particular attention is paid to people known to be susceptible (often the young, immunocompromised, or elderly). Although census data provide general information about population and household characteristics, they cannot be used to help interpret exposures of people who live in one area, but are exposed to site contaminants where they work. Personal habits that affect the results of exposure to contaminants (e.g., smoking) also cannot be measured.

Tinker is located on the eastern fringe of the Oklahoma City metropolitan area. The base is immediately south of Midwest City and east of Del City. Summary statistics from the 1990 Census are presented in Table 1a for the base, the area adjoining Crutcho Creek, and an area to the north and east of the base (see Figure 4a).³⁸

There were 3,699 persons living in the census tract that contains the base in 1990. Over 25 percent were under age 10. This figure is high relative to the general population but is typical of areas near military installations where high percentages of young couples with children reside. Nearly all households are renter-occupied, which reflects the transient nature of military populations. Base housing consists of 530 family housing units and seven dormitories. Less than 800 people lived in barracks in 1990. The Navy Facilities, completed in 1993, added two dormitories housing 208 personnel.

The area near Crutcho Creek (Figure 4) had a population of over 400 people. This neighborhood is racially diverse with a slightly above average percentage of persons under age 10 and a low percentage age 65 and older. Only 2.17 persons per household live in this area. This is a lower number than would be expected in a neighborhood with a high percentage of children.

One conclusion that can be drawn from these data is that a number of single-person households are in the area. This is consistent with the large percentage of rental units (82.4%).

The area north and east of the base (Figure 4b) had a 1990 population of 945. Nearly two-thirds of the households are owner-occupied, which indicates a nontransient population. This population is further subdivided into areas 1, 2, and 3; the statistics are presented in Table 1b. Those are the areas with confirmed contamination in drinking water wells. However, a large portion of residences and businesses in the three areas receive municipal water as the drinking water source.

Tinker is the largest single site employer in the state with approximately 22,000 employees.

Figure 4a.

Figure 4b.

Land Use

Midwest City is primarily composed of residential areas with small businesses, such as convenience stores, automotive repair shops, and rental storage, in neighborhoods adjoining the base. Del City is also composed primarily of residential areas and small businesses. Four elementary schools, three junior high schools, three high schools, and one junior college are within three miles of Tinker's northern border. Small home gardens are present in residential areas near Tinker, but no major agricultural operations are on base or within the immediate area.

One major industry, the General Motors Assembly Plant, is at the southern border of the base. The other major industrial facility in the area is Building 3001 at Tinker.

Base housing is on the west side of the installation near Crutcho Creek. A family campground, picnic area, and fishing pond are available for recreational purposes for base personnel and visiting military families at Tinker. A recreational park is near the golf course at Tinker. Two parks are within three miles of Tinker's northern border.

Natural Resources

Groundwater is used extensively in the area as a source of drinking water. Wells in the Kimsey residential area are within 50 yards of Tinker. Most of the wells in the area adjacent to Tinker (northeast of base) have been abandoned and plugged. Those residences have been provided municipal water.

Drinking water at Tinker is obtained from two sources. The first source is on-base groundwater wells (Figure 5).³⁹ Water is pumped out, chlorinated, and fluoridated at the pump stations. This comprises about 80 percent of the total amount of drinking water consumed on base. The second source is purchased water from Oklahoma City. Oklahoma City water may come from the Stanley Draper Lake System which is subsidized by the Otoka pipeline. Oklahoma City also provides water from Lake Hefner and Lake Overholser. City water enters the base at two locations. On the eastern side of the base, city water is pumped to a 500,000 gallon storage tank before entering the base-wide distribution system. On the south perimeter, city water is connected to the base-wide distribution system at facility 1106. Both base water and city water blend randomly in the system.

Crutcho Creek flows to the north and northwest of Tinker and empties into the North Canadian River about 5.5 miles north of the base. Both Kuhlman and Soldier Creeks empty into Crutcho Creek north of Tinker. Soldier Creek, which flows from Tinker into adjacent neighborhoods, is reportedly used for wading and playing by area children. Crutcho and Kuhlman Creeks are likely used by children for play areas since they flow through residential neighborhoods. Elm Creek is an intermittent stream that flows through an undeveloped area on base and an industrialized area off base. However, the area is not heavily populated with private residents. Therefore, it is unlikely that area children play in Elm Creek. This creek, however, discharges to Stanley Draper Lake.

Tinker has a small fishing pond at the campground area that is fished by base residents, personnel, and visitors. Soldier and Crutcho Creeks are large enough to support edible fish.⁴⁰ People fish in the Canadian River and in Stanley Draper Lake. No hunting or fishing has been reported to occur in the immediate area outside of Tinker, and hunting is not permitted on base.

Health Outcome Data

Health data that are available for the Tinker area include:

1. Vital statistics data (birth certificates, death certificates, and fetal death reports) at the state level.

2. A state tumor registry, currently being developed, that will provide cancer incidence data at the zip code level.

3. Riggin's Mortality Tapes are produced by the National Cancer Institute and EPA. They provide a comparison of the number of deaths resulting from a specific cancer type in a specified county and state with the number of deaths from the same cancer for the entire United States over a period of 30 years (in 10-year increments).

These data are further discussed in the "Health Outcome Data Evaluation" section of this document.

Figure 5.

ATSDR held public availability sessions on July 7 and 8, 1992, at the First Church of the Nazarene in Midwest City. Over 30 citizens attended and discussed their health and environmental concerns with ATSDR staff. Also, ATSDR held public availability sessions on May 19 and 20, 1993, at the Midwest City Public Library. Twenty eight citizens attended those sessions. The health concerns discussed are listed below. The health concerns are evaluated in the Community Health Concerns Evaluation section. The environmental concerns are listed in Appendix B.

The public availability sessions held July 7 and 8, 1992, and May 19 and 20, 1993, allowed citizens to talk about their concerns one-on-one with ATSDR staff. In addition, ATSDR talked with citizens and state and local health and environmental agency representatives during the site visits conducted at Tinker. Tinker's Community Relations Plan dated July, 1990, summarizes the concerns about the installation that were expressed to ATSDR by the state and local health departments and citizens. The health concerns are:

1. How extensive and harmful is the contamination of the Garber-Wellington aquifer? What about future water use?

2. How safe are the drinking water supplies?

3. Is the drinking water and coffee made with it safe to consume in building 3001?

4. Is our well water safe for laundry and showering --it has black particles in it and is greasy?

5. Could washing a parking lot with well water cause rashes and sores on legs?

6. Could past exposures to contaminated groundwater cause heart defects or chronic diarrhea in my daughter?

7. I live near the base. Is my fetus safe from contamination?

8. Is there an unusually high cancer rate in the communities surrounding Tinker?

9. Could lupus be related to base contamination?

10. How can the volatilization of jet fuel from the recent fuel spills affect our health?

11. Can children wading in Soldier Creek develop chloracne?

12. Is it safe for children to play in or around Soldier Creek?

13. Two children developed skin irritations after playing in East Soldier Creek downstream of the IWTP in August 1993. Could chemicals from Tinker have caused their skin irritations?

14. When wastewater from the base overflows into Crutcho and Soldier Creeks, can contaminants that are harmful enter these water systems?

15. Are the fish caught in Soldier Creek safe to eat?

16. Is it possible that contaminants have entered yards adjacent to Soldier Creek and would garden vegetables from those yards be harmful if consumed?

17. Our garden vegetables and plants have black, oily particles on them? What could it be and is it safe?

18. Is the air safe in the vicinity of the IWTP?

19. I live adjacent to the base and experience sinus problems and a tight chest periodically. Could this be caused by contaminated water and air pollution from the IWTP?

20. I live adjacent to the base and have experienced dermal reactions such as dry and itchy scalp, rashes, open sores, and skin growths. Could this be caused by contaminated water and air pollution from the IWTP?

21. Will children enrolled at the Childhood Development be safe from contamination?

22. Is it safe for employees to work near the hazardous waste sites?

23. Is it safe to hunt? Is the wildlife safe?

These concerns are evaluated in the Public Health Implications: Community Health Concerns Evaluation section of this document.

Agency for Toxic Substances and Disease Registry, 1825 Century Blvd, Atlanta, GA 30345
Contact CDC: 800-232-4636 / TTY: 888-232-6348 

Department of Health and Human Services