PUBLIC HEALTH ASSESSMENT
KELLY AIR FORCE BASE
SAN ANTONIO, BEXAR COUNTY, TEXAS
In response to a petition requesting an ATSDR investigation of potential health issues in the neighborhoods north and southeast of Kelly by the late Congressman Frank Tejeda, ATSDR conducted an initial site visit in late August 1996.
A site summary document describing ATSDR's preliminary evaluation of issues at Kelly AFB was published and distributed in October 1996. In March and May of 1997, ATSDR published health consultations which described the evaluation of potential health effects of specific, independent events that occurred in the East Kelly neighborhood, an area not included in the original petition. (These consultations are available in the repositories or can be obtained by contacting ATSDR).
This document is a public health assessment and describes ATSDR's evaluation of potential releases of hazardous substances from Kelly AFB. The public health assessment for Kelly AFB will consist of three phases.
- Phase I is represented by this document and consists of ATSDR's evaluation of community concerns involving environmental contamination from Kelly AFB and health outcome data, as addressed in the original petition.
- Phase II will address those issues identified in Phase I as warranting further evaluation, including the evaluation of past air emissions and the continued evaluation of health outcome data as identified herein.
- Phase III will address issues identified outside the purview of the original petition, but expressed as concerns by the community. Phase III will include an evaluation of the potential environmental contamination of East Kelly and an evaluation of the potential contamination of on-base drinking water.
Phase I of the public health assessment is composed of four primary sections:
- The Exposure Pathways and Human Health Assessment section addresses potential environmental exposures and health implications that may be predicted from the potential exposures.
- The Community Health Concerns section relates concerns expressed by community members in addition to ATSDR activities involving the communities around Kelly AFB.
- The Health Outcome Data section contains documented health outcomes reported by hospitals, physicians, clinics, and others, and is organized into sections on cancer, birth outcomes, and lead.
- The Child Health Issues section addresses general child health issues as well as child health issues specific to the site.
ATSDR makes conclusions about the health implications associated with a site and designates a health hazard category which describes the health implications for each pathway. A complete description of the hazard categories is presented in Appendix A. The Exposure Pathways and Human Health Assessment section has been organized into three distinct divisions, relating to the level of public health hazard categories designated at Kelly AFB.
- The indeterminate category in used when critical data are insufficient with regard to extent of exposure and/or toxicologic properties at estimated exposure levels. This category includes the air exposure pathway in which exposure has occurred in the past. The past air exposures are categorized as indeterminate because critical information must be obtained and evaluated before determination of the public health issues. Exposure to lead in soils is also included in the indeterminate category because ATSDR has limited environmental data for soils in the neighborhood but believes that levels in soil are likely to be below levels of health concern. However, exposure can come from other sources, such as lead-based paint, soldered water pipes, and pesticides. ATSDR needs additional information before it can determine a public health hazard due to exposures to lead.
- The no apparent public health hazard category contains those issues for which ATSDR has found that exposure may have occurred, may be occurring, and/or may occur in the future, but for which the exposure is not expected to cause adverse health effects. No further investigation by ATSDR is indicated for issues in this category, unless new data or information suggests that additional investigation is warranted.
- The no public health hazard category contains issues for which no further action by ATSDR is indicated because no exposure has occurred.
Where possible, data and other technical material from those sections requiring more extensive analysis (air modeling evaluation, Leon Creek evaluation, demographic and health outcome data) have been placed in the appendixes, to enable a more readable text. Also included in the appendixes are the incomplete Health Outcome Data and evaluations of Community Reports, comprised of the District 4 Primary Health Care Review and the North Kelly Gardens Comprehensive Symptom Survey.
Kelly Air Force Base (AFB) was founded on May 7, 1917. It is located in Bexar County, Texas, approximately 7 miles southwest of downtown San Antonio (Figure 1, page 7). The base encompasses 4,660 acres and is bounded on the west by Lackland AFB and to the south by Military Drive and Leon Creek. The northern and eastern boundaries are Growdon Road and the Union-Pacific Railroad Yards, respectively. The surrounding community is mostly residential, commercial, and light industrial with limited agriculture. Although aircraft repair and maintenance was continuous from the time flying began at Kelly in 1917, the base became a major overhaul and logistics center with the move of the Army Air Service Aviation Repair Depot to Kelly from Dallas in 1921. This move created the San Antonio Intermediate Depot, the predecessor of today's San Antonio Air Logistics Center (SA-ALC). The SA-ALC manages an extensive inventory for the USAF, including aircraft engines, weapons systems, support equipment, and aerospace fuels. Since 1954, Kelly AFB has been involved with logistics and maintenance for the SA-ALC. Kelly AFB hosts the 433rd Airlift Wing, which operates the C-5 aircraft, and the 147th Fighter Wing, which operates the F-16 aircraft. In addition, aircraft such as C-5s, T-38s, B-52s, C-130s, B-58s, and F-100s are or have been maintained and repaired at Kelly AFB (1).
Environmental restoration activities were initiated at Kelly AFB in 1982 under the Air Force's Installation Restoration Program (IRP). Between 1982 and 1988, remedial investigations consisting of preliminary assessments and site inspections were performed to identify areas of the base which contained hazardous wastes. Fifty-two areas were discovered and potential alternatives for cleanup are being addressed. Feasibility studies have been conducted and, where appropriate, interim remedial actions to contain or abate contamination have been initiated or are planned. The environmental work at Kelly AFB continues, as characterization of groundwater plumes and cleanup is not complete (2).
In 1995, the independent Base Realignment and Closure Commission (BRAC) selected the eastern portion of Kelly AFB for closure of the San Antonio Air Logistics Center (SA-ALC). The western portion was targeted for realignment of the flight line, various tenant organizations, and select properties adjacent to Lackland AFB (3). Closure of the SA-ALC and realignment of the remaining facilities is currently scheduled to begin in 2001. An attempt to privatize portions of the base scheduled for closure is under consideration. Future owners and activities have not been finalized.
The geography around Kelly AFB consists of gently undulating prairie, generally sloping to the southeast toward the Gulf of Mexico. The topography of Kelly AFB is generally flat with elevations ranging from 610 to 730 feet above sea level. Kelly AFB is situated over a shallow aquifer and a deeper, confined aquifer (Edwards aquifer). The shallow aquifer occurs in alluvial sediments that overlie various clays, marl, and rock; and water is present at depths of 3 to 37 feet across the base. The layer of clay under the shallow aquifer is found at depths to 50 feet and is about 450 feet thick. Under the clay layer lie 300 feet of marl and 500 feet of limestone and shale. These layers overlay and confine the deeper Edwards aquifer, which is the main source of drinking water for the San Antonio area. The shallow aquifer is therefore separated from the Edwards aquifer by this very thick, impermeable layer of mostly clay, marl, and rock (4).
The climate of San Antonio is continental and subtropical and has two main seasons consisting of a dry, mild winter and a hot, humid summer. Northerly winds prevail during most of the winter (October through February), while southeasterly winds from the Gulf of Mexico prevail during the summertime (March through September). Southeasterly winds may also be experienced for long periods during the winter (4).
Precipitation is well distributed throughout the year, with the heaviest amount historically occurring during May and October. Precipitation between April and September usually occurs as thunderstorms, with heavy rains falling in short periods of time. Most of the winter precipitation occurs as light rain or drizzle (4).
Demographics were compiled from the 1990 Census from summary tapes on Texas (5) and are presented in Figure 5 (page 27) and Appendix B. Demographics from the zip codes of primary interest, 78211 (Quintana Road area) and 78237 (North Kelly Gardens area), were assembled as well as individual Track 1607.85, Block Group 4 (located in North Kelly Gardens) and individual Track 1609, Block Group 4 (located in the Quintana Road area), which were located within the zip codes.
Demographic data provide information on population characteristics and can sometimes help provide explanations for elevated disease incidence. Demographic information will help define special populations at risk. In addition, relevant information about the community living near hazardous waste sites may include the number and location of health care providers, schools, hospitals, day care centers, and nursing homes in relation to specific hazardous waste sites.
The neighborhoods surrounding Kelly AFB are predominately Hispanic (89%-94%), compared to 50% for Bexar County and 26% for Texas, with slightly more females (52%-53%) than males. Residents less than 10 years of age comprise 22%-24% of the population, and 6%-8% of the population are 65 years of age and older. The population is slightly younger than that of Bexar County or Texas with the majority of residents being under 30 years of age. Residents own their home slightly more than the county or state average. The population below the poverty level ranges from 26%-39% (5). Seventy percent of the housing in the Quintana Road community (population 1700) was constructed in the 1950s and 1960s, and 65% of the housing in the North Kelly Gardens community (population 800) was constructed during the 1960s and 1970s (6,5). Fifty-seven percent (57%) of the North Kelly Gardens community lived there before 1980. Fifty-five percent of the current residents of the Quintana Road community lived there before 1980. The population in these areas is relatively stable because approximately half have continued to live in this area for nearly 20 years.
Prior to development in the 40s and 50s, the area was mostly agricultural and consisted of cultivated fields. Agriculture is presently limited, and land use is mostly residential, commercial, and light industrial.