PUBLIC HEALTH ASSESSMENT
(a/k/a FORT RILEY MILITARY RESERVATION)
FORT RILEY, GEARY COUNTY, KANSAS
The Agency for Toxic Substances and Disease Registry (ATSDR) has prepared this public health assessment to evaluate the potential for contaminants from Fort Riley Military Reservation (Fort Riley) to cause harm to people living near or accessing the installation. Based on a review of the available information, ATSDR finds that Fort Riley poses no apparent public health hazard.
Fort Riley is an active military facility occupying over 101,000 acres in Riley, Geary, and Clay Counties, Kansas. Founded in the 1850s, Fort Riley has served as a center for military education and readiness. Over the years of operations, hazardous materials used in light industrial or general post support operations have been spilled or released to the soil or the underlying groundwater due to accidents and/or poor past waste management practices. Principal contaminants at the installation are volatile organic compounds (VOCs)—primarily trichlorethylene (TCE) and tetrachloroethylene (PCE)—pesticides, and metals. As a result of these releases, the U.S. Environmental Protection Agency (EPA) placed Fort Riley on the National Priorities List of hazardous waste sites to be investigated on October 30, 1990.
As part of the public health assessment process, ATSDR conducted site visits and met with representatives from the community, Fort Riley, the Army, and local health departments in 1991 and 1994. During the site visits, ATSDR did not identify any immediate public health hazards or completed exposure pathways of concern but determined that more information was needed to more fully evaluate potential exposure to contaminated groundwater and on-post soil.
Since ATSDR’s initial site visits, ATSDR revisited the installation in 1998 and reviewed data gathered to date from additional site investigations. Groundwater monitoring data revealed that concentrations of VOCs in a number of on-post groundwater monitoring wells located at the Marshall Army Airfield Former Fire Training Facility (MAAF-FFTA) exceeded the maximum contaminant levels (MCLs), drinking water standards for public water supplies considered protective of public health by EPA. While no harmful levels of VOCs were found in on-post drinking water supply wells or in off-post municipal wells, VOCs were detected at concentrations above MCLs in off-post private wells serving the downgradient auto speedway. Despite these detections, ATSDR determined that limited consumption of water from these private wells in the past did not pose a public health hazard. No exposure is occurring, nor is expected in the future, because the wells have not been used for drinking water since 1993. Fort Riley continues to clarify the extent to which TCE/PCE groundwater contamination associated with the MAAF-FFTA has migrated beyond installation boundaries.
ATSDR did not identify any past, current, or future public health hazards associated with on-post or off-post soil. Although isolated areas of the installation contained elevated levels of lead or pesticides in the past, contact with the most contaminated soil, if any, was likely brief and infrequent, and not at levels of health concerns. No harmful exposures are occurring now, nor are they expected to occur, because Fort Riley has excavated lead- and pesticide- contaminated soil from the contaminated areas. Fort Riley will excavate lead-contaminated soil from an off-post area of contamination (the Southeast Funston Landfill and Incinerator Area) before use of the area increases; past and current use of the area has been limited and thus contamination does not pose a public health hazard.
Fort Riley Military Reservation (Fort Riley) is an active military facility located on approximately 101,000 acres north of Junction City in Riley, Geary, and Clay Counties, Kansas (see Figure 1). Fort Riley is largely comprised of undeveloped land dedicated to military training, but portions of the installation are developed for military support operations. Developed areas include an approximately 20-square-mile Multipurpose Range Complex, the Artillery and Mortar Impact Area, and six cantonment areas. The six cantonment areas, which include the Main Post, Camp Forsyth, Camp Funston, Camp Whitside, Marshall Army Airfield (MAAF), and Custer Hill, are geographic areas grouped together because of similar functional histories (see Figure 2). Camp Funston, Camp Whitside, and the Main Post are situated on the lowlands of the alluvial plains along the northern bank of the Kansas River. Camp Forsyth is located along Republican River, before its confluence with the Smoky Hill River. Custer Hill is above these areas in the uplands. MAAF lies on the south side of the river, just across from the Main Post. Land surrounding the installation consists of undeveloped land and small nearby communities, including Junction City and Grandview Plaza to the south; Ogden to the southeast; Milford to the west, and Riley to the north (Louis Berger & Associates, Inc., 1993a).
Fort Riley was established in 1852 as a military outpost near the confluence of the Smoky Hill and Republican Rivers. Over its years of operations, the post has served as a center of military readiness, primarily training troops and supplying and maintaining military equipment. In carrying out its mission, the post performs light industrial or general post support operations, including dry cleaning, furniture repair, printing, solid waste disposal, wastewater treatment, wastewater discharge, pesticide applications, landfilling, and general infrastructure maintenance. As a result of some of these installation activities, hazardous materials and chemicals have been released to the soil in portions of the installation either inadvertently or because of poor past waste management practices, eventually reaching the underlying groundwater (Louis Berger & Associates, Inc., 1993a).
Environmental contamination at Fort Riley first became evident during the closing of the 120-acre Southwest Funston Landfill (SFL) in 1981. At the time, groundwater monitoring required by the state of Kansas Department of Health and Environment’s (KDHE’s) landfill closure approval process, revealed the presence of volatile organic compounds (VOCs) in groundwater beneath the landfill (Fort Riley, 1998a). In 1983 and 1984, the Army detected polychlorinated biphenyls (PCBs) (related to transformers) and pesticides (related to pre-1976 pesticide storage and application practices) in the soil and sediment of a drainage channel of the Pesticide Storage Facility (PSF) located on the Main Post (Fort Riley, 1995, 1997).
The U.S. Environmental Protection Agency (EPA) placed Fort Riley on the National Priorities List on October 1, 1990, based on an aggregated hazard ranking for the PSF and the SFL (Fort Riley, 1995, 1997). EPA’s reasoning for combining the two contaminant source areas was that they potentially affected the same shallow aquifer and target population. Principal site contaminants associated with these areas include VOCs—primarily trichloroethylene (TCE) and tetrachloroethylene (PCE)—pesticides, and metals. Table 1 provides a detailed description of contaminant source areas.
EPA Region VII, the Army, Fort Riley, and KDHE negotiated a Federal Facility Agreement (FFA) (also known as the Interagency Agreement) to integrate the Army’s Resource Conservation and Recovery Act (RCRA) corrective actions with obligations of EPA’s Superfund program so that any required future investigations for contaminants regulated by Superfund laws are based on Superfund guidelines. (Petroleum, oil, and lubricant contamination is not part of the Superfund program and is investigated at Fort Riley under RCRA Subpart I using guidance from the state of Kansas [Fort Riley, 1999a) At the time, the FFA specified that the Army conduct a remedial investigation (RI) and feasibility study (FS) at both the PSF and the SFL. The FFA also required the Army to conduct a systematic installation assessment in which they identified all other areas of contamination located at Fort Riley (Louis Berger & Associates, Inc., 1993a).
In carrying out their obligation under the FFA, the Army conducted an Installation Wide Site Assessment in 1992. Through this assessment, they identified 24 groupings of potential areas of contamination (PAOCs) consisting of over 45 individual PAOCs; some of these were thought to potentially pose a significant threat to human health and the environment (Louis Berger & Associates, Inc., 1993a). The Army determined that 11 of the groups of PAOCs required further environmental evaluation (Fort Riley, 1998b).
The Army has designated five operable units (OUs) at Fort Riley, encompassing areas containing significant contamination from past and present operations that caused spills and releases to the environment. The OUs are: the SFL (OU1), the PSF (OU2), the Dry Cleaning Facility (DCF) (OU3), Marshall Army Airfield-Former Fire Training Area (MAAF-FFTA) (OU4), and Building 354 Area Groundwater Solvent Detections (OU5). The OUs are in various phases of field investigations or cleanup as follows: OUs 1 and 2 have record of decisions (RODs) that outline the cleanup process; OUs 3 and 4 have had contaminated soil removed via SVE extraction pilot studies and/or bioventing; and OU5 is in early phases of RI field investigations (Fort Riley, 1999b). Table 1 also describes the OUs in greater detail.
As part of the public health assessment process, the Agency for Toxic Substances and Disease Registry (ATSDR) conducted an initial site scoping visit and met with representatives from the Army and Fort Riley on July 31 and August 1, 1991. At the time of the visit, ATSDR toured the installation, reviewed installation files, and interviewed installation personnel to gather information about potential pathways of human exposure to contaminants at the installation. ATSDR revisited the installation between October 29 and November 1, 1991, to meet with community members and representatives from the cities of Manhattan and Junction City and from the Riley County and Geary County Health Departments. ATSDR visited the installation again in 1994 to discuss findings of ongoing investigations. From these meetings and a review of the data then available, ATSDR determined that no completed pathways of human exposure existed, but that additional site information was needed to more fully evaluate several potential exposure pathways.
Since 1994, additional site information has become available. ATSDR revisited the installation between December 7 and 9, 1998, to meet with representatives from the KDHE, Army, and Fort Riley, and to gather more recent environmental monitoring data. ATSDR also attended a Restoration Advisory Board (RAB) meeting where ATSDR staff listened to community issues and presented an overview of the public health assessment process. About 20 community members representing diverse backgrounds attended the meeting. During the site visit, ATSDR determined that no immediate threats to public health existed, but that two potential human exposure pathways required further evaluation. The first pathway involves ingestion of contaminated drinking water from a well that served the concession stand at the nearby auto speedway in the past. The second pathway involves exposure to pesticides and lead-contaminated soil that has been found in secured work areas or residential areas on post and one site off post. These pathways are further evaluated in the "Evaluation of Potential Exposure Pathways" section of this document.
ATSDR examines demographic information, or population information, to identify the presence of sensitive populations, such as young children and the elderly, in the vicinity of a site. Demographics also provide details on residential history in a particular area—information that helps ATSDR assess time frames of potential human exposure to contaminants. Demographic information for the residential areas surrounding Fort Riley is presented in this section.
Today, the population at Fort Riley exceeds 30,000 persons with approximately 10,000 military personnel, 12,400 family members, 6,000 retirees, and 3,300 civilians. To accommodate its large military population, Fort Riley provides a multitude of housing options, including family quarters (2,922 units), bachelor officer/senior enlister quarters (47 units), transient quarters (119 rooms), and barrack capacity (4,531 units). Young children living at Fort Riley are likely to attend one of six on-post schools (five elementary and one middle/junior high school) or one of the several child care centers (Fort Riley, 1998c).
ATSDR also reviewed land use at or near Fort Riley to identify valuable information on the activities conducted in the surrounding area and the possibility of exposure through these activities. As mentioned, Fort Riley functions as a small municipality and light industrial complex. Much of the vast, undeveloped land serves as grounds for military training. Fort Riley’s undeveloped land and rivers and ponds also serve as popular outdoor recreational spots for hunting and fishing. Its wide open fields support a large quail and deer population and the largest elk herd (200 to 225 free-ranging elk) in Kansas. According to Fort Riley’s Conservation Division, hunters make more than 6,500 hunting trips annually to Fort Riley (Louis Berger & Associates, Inc., 1993a; Fort Riley, 1999c).
The land surrounding Fort Riley consists of undeveloped and agricultural land and scattered residences. Several small communities towns border Fort Riley, including Junction City adjacent to the south (approximately 20,000 persons), Grandview Plaza adjacent to the south (less than 1,000 persons), Ogden adjacent to the southeast (approximately 1,400 persons), and Riley adjacent to the north (approximately 800 persons). Also, the Manhattan Municipal Airport is located within 1 mile to the east of Fort Riley (Louis Berger & Associates, Inc., 1993a).
Fort Riley and the surrounding communities rely on groundwater for their primary source of drinking water. Several municipal wells are located in the alluvial (river) and valley fill deposits of the Kansas River and the Republican River. These alluvial deposits produce groundwater that is recharged, or replenished, through direct infiltration of rain and, to a limited extent, from seepage from the adjacent limestone aquifers. Groundwater is also produced, to a lesser degree, from solution channels and fractures in the Permian Age limestone bedrock aquifer that underlies the unconsolidated overburden.
The depth and presence of groundwater varies depending on local physiographic, geologic, and hydrologic conditions, but the alluvial aquifer is encountered at between 10 and 30 feet below ground surface (bgs) and the bedrock aquifer is encountered between 60 and 100 feet bgs. The regional direction of shallow groundwater flow is generally toward the Kansas River, though the groundwater flow direction near the Kansas River can be toward or away from the river depending on the stage fluctuations of the river (Law Engineering and Environmental Services, Inc., 1995). Groundwater flow from the majority of the post is from the uplands to the south and southeast toward the river. Flow at the MAAF-FFTA is generally north, paralleling the river for some distance, then intersecting with it (Louis Berger & Associates, Inc., 1997a).
Fort Riley sits along the banks of the Kansas River, which is formed by the convergence of the Republican and Smoky Hill Rivers. Flooding may occur in the lowlands, along the Republican and Kansas Rivers; portions of the Main Post are located in the 100-year floodplain (Louis Berger and Associates, Inc., 1993a; Law Engineering and Environmental Services, Inc., 1995). Camp Forsyth, Camp Funston, and MAAF are protected from a 100-year flood event by levees (Fort Riley, 1999a). Many other large water bodies associated with the Kansas River system, such as Milford Lake, are situated around Fort Riley. Intermittent and perennial creeks that flow through Fort Riley, eventually empty into one of the larger nearby area water bodies or rivers. Many of the area water bodies and rivers are used for fishing and boating, but there are no documented drinking water uses of surface water downstream of the installation, including in the immediate downstream areas of the Kansas River. As mentioned, most of the nearby communities rely on groundwater-supplied municipal wells for their source of drinking water, all of which are located several miles from the Main Post of Fort Riley (Louis Berger & Associates, Inc., 1993a).
In preparing this public health assessment, ATSDR relied on the information provided in the referenced documents. Documents prepared for Fort Riley meet specific standards for adequate quality assurance and control measures for chain-of-custody procedures, laboratory procedures, and data reporting. The validity of the analyses and conclusions drawn in this document are dependent upon the availability and reliability of the referenced information. The environmental data presented in this public health assessment are from reports produced by the environmental investigations at Fort Riley and discussions with KDHE and local officials.