PUBLIC HEALTH ASSESSMENT
WELDON SPRING SITE REMEDIAL ACTION PROJECT
(CHEMICAL PLANT, RAFFINATE PITS, QUARRY)
ST. CHARLES, ST. CHARLES COUNTY, MISSOURI
The U.S. Department of Energy Weldon Spring Site Remedial Action Project (chemical plantsite), is a former uranium processing facility located in eastern Missouri on the property of theformer U.S. Army Weldon Spring Ordnance Works. The chemical plant site consists of twononcontiguous areas: 1) the 205-acre chemical plant area which includes several raffinate pits,and 2) the quarry. Surface water, soil, sludge, sediment, and groundwater within the chemicalplant site contain chemical and radioactive contaminants.
The Agency for Toxic Substances and Disease Registry (ATSDR) reviewed on-site chemicalexposure information and site conditions. Currently, public access to the chemical plant site isrestricted by fences and 24-hour guards at entry gates. Therefore, current public exposurepathways to on-site chemical contaminants are incomplete, and no exposure exists to pose apublic health hazard. However, in the past, trespassers may have gained access to the site andswam in the quarry and raffinate pits. ATSDR evaluated their potential exposure and found thattrespassers' infrequent short-term exposure to chemical contaminants was highly unlikely toresult in health effects.
The chemical plant site is surrounded by the U.S. Army Weldon Spring Ordnance Works Sitewhich includes the August A. Busch Memorial Conservation Area, Weldon Spring ConservationManagement Area, the Weldon Spring Training Area, and other small properties. These areas areconsidered the off-site areas. ATSDR completed a Public Health Assessment on the WeldonSpring Ordnance Works Site in March 1995. ATSDR scientist re-evaluated potential exposuresin those areas and concluded that exposure to chemical contaminants in surface water,groundwater, water from the St. Charles County well field and off-site private wells, and effluentreleases from the chemical plant site to the Missouri River does not pose a public health hazard.In addition, recreational consumption of fish and game within the training area and theconservation areas poses no apparent public health hazard. ATSDR also prepared severalHealth Consultations on chemical and radioactive contaminants in areas on and off the DOEchemical plant site. The findings of these prior ATSDR evaluations are included whereappropriate in this Public Health Assessment on the chemical plant site.
ATSDR also reviewed on-site and off-site radiological exposure information and conditions. Theexposure scenarios ATSDR evaluated include: trespassers swimming in quarry or raffinate pits;reservists performing field activities in the training area; anglers fishing, hunters hunting, andhikers hiking in the conservation areas; residents drinking from off-site private wells; staff andstudents attending the Francis Howell High School; and consumers of crops (e.g., corn) grown inconservation areas. In all of the scenarios evaluated, past and current exposures to radionuclidespose(d) no public health hazard or no apparent public health hazard.
Through a series of meetings, telephone calls and correspondence, ATSDR has obtainedinformation on the community's concerns about contaminant exposures and specific healtheffects related to the chemical plant site. Local residents have expressed concern about: (1)exposures to airborne radioactive contamination at the Francis Howell High School, (2)consumption of contaminated fish from lakes in the conservation areas, (3) contaminantmigration to the St. Charles County well field and potential contamination of the County watersupply, and (4) a potential increased incidence of childhood leukemia in St. Charles County.ATSDR has evaluated these community concerns as part of this health assessment. In summary,
- Air monitoring conducted at the site boundary and the high school has shown that airborne radioactive contaminants are not moving beyond the site boundary, and radiation levels at the high school are within normal background ranges.
- Contaminant concentrations in fish are very low, and recreational consumption of fish from the conservation areas does not pose a public health hazard.
- Groundwater contaminants from the Weldon Spring quarry have not migrated to the St. Charles County well field, and ongoing remediation at the quarry will further reduce the potential for contaminant migration. Current groundwater monitoring procedures are adequate to determine the distribution of contaminants.
- Cancer incidence data from the Missouri Cancer Registry indicate that there may have beenhigher than expected rates of childhood leukemia for several years during the period 1983-1992.However, the geographical distribution of these cases suggests that these cases are not related tocontaminant exposures at the chemical plant site. In addition, exposure to the types and levels ofcontaminants present at the site has not been shown to cause childhood leukemia. ATSDR willwork cooperatively with the Missouri Department of Health to further investigate possibleenvironmental factors for the childhood leukemia cases in St. Charles County.
ATSDR evaluated available environmental monitoring data obtained from the U.S. Departmentof Energy, the Missouri Department of Natural Resources, St. Charles County, and the U.S.Department of the Army. ATSDR evaluated human exposure pathways to chemical andradioactive contaminants at the site. ATSDR also evaluated health information from the MissouriDepartment of Health to address community health concerns.
Based on these evaluations of environmental data, human exposure pathways, human healthoutcomes, and community concerns, ATSDR has determined that the chemical plant site posesno apparent public health hazard to the general public. Access restrictions prevent publicexposure to chemical and radioactive contaminants on-site. In general, the public is not exposedto chemical and radioactive chemicals off-site. However, any exposures to off-site contaminantsare expected to be infrequent and short-term and do not pose a public health hazard.
The Weldon Spring Site Remedial Action Project (chemical plant site) is in southern St. CharlesCounty, Missouri, about 30 miles west of St. Louis (see Figure 1). The chemical plant site,currently administered by the U.S. Department of Energy (DOE) for environmental restorationand site cleanup, is a former uranium refining facility. DOE is responsible for chemical andradioactive contaminants within the chemical plant site and all off-site radioactive contaminantsfrom the site. The chemical plant site is on the U.S. Environmental Protection Agency's (EPA)National Priorities List (NPL), and restoration is overseen through the EPA Superfund process.
The DOE's chemical plant site consists of two noncontiguous areas: (1) the chemical plant areaand (2) the quarry (see Figure 2). The 205-acre chemical plant area includes buildings, supportstructures, Ash Pond, Frog Pond, and raffinate pits (see Figure 3). The chemical plant area wasfirst used to produce 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), and 2,6-dinitrotoluene (DNT) and later to process uranium and thorium. The Ash Pond is a surfaceimpoundment, and the Frog Pond is a waste settling basin within the chemical plant area. Fourraffinate pits are waste settling basins used in the processing of uranium and thorium. The nine-acre quarry was used for waste disposal.
This public health assessment on the Weldon Spring Site Remedial Action Project (chemicalplant site) addresses public exposures to chemical and radioactive contaminants within the DOEchemical plant site (chemical plant area, raffinate pits, and quarry) and to radioactivecontaminants released from the chemical plant site into the off-site environment. The assessmentalso addresses the health concerns voiced by members of the surrounding community. Thesecommunity concerns include exposure concerns (ways that people may have eaten, drunk, orinhaled contaminants) and health concerns (specific illnesses those community members feel thatexposure to site contaminants may have caused).
The DOE chemical plant site is surrounded by the U.S. Army Weldon Spring Ordnance Workssite, which is also listed on the EPA NPL because of contamination from the production of TNTand DNT (explosives) during World War II. The Weldon Spring Ordnance Works NPL Siteincludes the Weldon Spring Training Area, August A. Busch Memorial Conservation Area,Weldon Spring Conservation Management Area, and many other small properties within theoriginal 17,232 acres of U.S. Army property (see Figure 2) . The Army is responsible for allchemical contamination within the Weldon Spring Ordnance Works NPL Site . The Agencyfor Toxic Substances and Disease Registry (ATSDR) completed a Public Health Assessment onthe Weldon Spring Ordnance Work Site in March 1995. The 1995 public health assessmentaddressed issues related to chemical exposures at the Weldon Spring Ordnance Works Site.ATSDR also prepared several health consultations on chemical and radioactive contaminants inthe chemical plant site and in the Weldon Spring Ordnance Works Site. The findings of theseprior ATSDR evaluations are included, where appropriate, into this Public Health Assessment onthe chemical plant site to address community exposure concerns.
This public health assessment does not address exposure to past chemical plant workers or toworkers involved in remediation-related activities. EPA and the Department of Labor,Occupational Safety and Health Administration (OSHA) require that workers involved in siterestoration be trained in the use and safe handling of hazardous materials and follow strict site-safety plans and operational procedures
In 1941, the U.S. Department of the Army procured approximately 17,000 acres of land in St.Charles County to build the Weldon Spring Ordnance Works facility. From 1941 to 1946, thefacility produced 2,4,6-trinitrotoluene (TNT) and 2,6-dinitrotoluene (DNT) on 20 chemicalprocess lines. The facility was declared surplus property in 1946, and between 1947 and 1949,approximately 15,000 acres were transferred to the State of Missouri, the University of Missouri,and the St. Charles County Public School District.
Of the remaining 2,000 acres under control of the U.S. Department of Army in 1955, 205 acreswere transferred to the Atomic Energy Commission for the construction of a uranium refiningfacility. This 205-acre parcel consisted of the chemical plant site. The Mallinckrodt ChemicalWorks processed uranium and thorium ores into metal compounds from 1957 until the plantclosed in 1966. The chemical plant site was returned to the U.S. Department of Army control in1967 for construction of a herbicide production facility. Decontamination of the uranium refiningfacilities was attempted from 1968 to 1970, but abandoned because of cost. In 1972, St. CharlesCounty acquired the plant well field and water treatment plant.
The U. S. Department of Energy (DOE) regained control of the chemical plant site in 1984 andbegan site characterization and remediation in 1986. The quarry was placed on the NationalPriorities List (NPL) in 1987, the listing was expanded to include the chemical plant area andraffinate pits in 1989. The U.S. Army-controlled Weldon Spring Ordnance Works site was listedseparately in 1990.
The chemical plant site is in eastern Missouri, within the confluence of the Mississippi andMissouri rivers. The Weldon Spring Ordnance Work Site which surrounds the chemical plantsite (chemical plant area and quarry) covers two land types. The northern portion, including thechemical plant area, is characterized by moderately hilly, northward dipping topographycomprising thin glacial deposits overlying limestone bedrock . The southern portion of thesite, including the quarry, is characterized by rugged topography with narrow irregular drainagesystems with short and steep gradient streams. The transition between these land types occursjust south of the chemical plant area and corresponds with a primary drainage basin and agroundwater divide that diverts water north to the Mississippi River and south to the MissouriRiver .
Annual precipitation for this area averages approximately 37 inches per year, with more than halfoccurring as rainfall between March and July. Annual evaporation, based on average free watersurface evaporation (1956-1980 data) is approximately the same as precipitation (~37 inches peryear). Prevailing winds are from the south during summer and fall and from the northwest andwest-northwest during winter and spring. Average wind speeds are about 8.7 miles per hour(mph) for May through November and 10 mph for December through April .
Three aquifers are present within the region of the chemical plant site: an alluvial aquifer in thesaturated sand and gravel next to the Mississippi River and the Missouri River, a shallowbedrock aquifer that occurs throughout most of the area, and a deep bedrock aquifer.
The alluvial aquifer is unconfined, and the water table surface is at or within a few feet of theland surface. Thickness of the alluvial aquifer decreases rapidly away from the rivers, but in theSt. Charles County municipal well field, the alluvial aquifer has a thickness of 100 to 110 feet.Water in the alluvial aquifer generally moves to and discharges into the adjacent rivers .Hydraulic conductivities are very high in this aquifer, calculated to be between 535 and 600 feetper day .
The upper portion of the shallow bedrock aquifer exhibits some karstified features with fracturesand joints enlarged by dissolution; however, it is not strictly classified as karst . Theuppermost limestone has weathered to clay, but fracture permeability is high so overallpermeability/hydraulic conductivity decreases downward into the unweathered, competentlimestone. In areas where the overlying glacial till or weathered limestone is absent or eroded, theshallow bedrock aquifer may discharge either to springs or to surface streams that may rechargethe aquifer at swallow holes . A groundwater divide follows surface topography and streams,with groundwater flowing northward from most of the site and southward from the southernportions of the site .
The St. Charles County Water Department currently owns and operates the municipal well fieldalong the Missouri River. The well field is approximately one-half mile south of the quarry.Eight municipal wells pump an average of 12 million gallons of water per day from the alluvialaquifer. These wells can pump a maximum of 22 million gallons per day. Well depths vary from100 to 130 feet in depth. Water from this Weldon Spring municipal well field is sold to theMissouri American Water Company, formerly the Missouri Cities Water Company, which servesabout 60,000 people throughout St. Charles County. Also, approximately 60 private water wellsare near the chemical plant site . We do not know the details of well construction and usage.However, the State of Missouri has conducted a well survey (although it was not a completecensus of the entire area) and monitors many of these wells for site-related contaminants(unpublished well survey and analytical results, summary data in ).
The DOE chemical plant site (chemical plant area and quarry) is surrounded by the U.S. ArmyWeldon Spring Ordnance Works Site (Weldon Spring Training Area, August A. Busch MemorialConservation Area, and Weldon Spring Conservation Management Area) (see Figure 2).
The U.S. Army Weldon Spring Training Area comprises about 1,700 acres, with approximately200 acres used for training troops and the remaining portion dedicated to site cleanup anddecontamination activities. Remaining areas surrounding the chemical plant site are within theAugust A. Busch Memorial Conservation Area and the Weldon Spring ConservationManagement Area (conservation areas).
The August A. Busch Memorial Conservation Area consists of about 8,000 acres on the northboundary of the chemical plant site, and the Weldon Spring Conservation Management Area isabout 7,000 acres to the south. The Missouri Department of Conservation maintains andadministers both conservation areas. The department has a multiple-use philosophy of landmanagement. The conservation areas serve as forest and refuge for a variety of wildlife and birds;32 stocked lakes provide fishing opportunities; and approximately 1,000 acres south of the quarryand along the Missouri River floodplain are used for land lease farming of grains and foragecrops. No livestock are raised on the leased land. Several employees of the Missouri Departmentof Conservation live with their families in the August A. Busch Memorial Conservation Area.
Seasonal hunting for squirrel, groundhog, dove, rabbit, white-tailed deer and wild turkey occursby special permit. Edible aquatic species in the lakes in the August A. Busch MemorialConservation Area include black bass, white bass, channel, flathead and blue catfish, crappie,bluegill, carp, sunfish, and crayfish. Hunting dog field trials take place on portions of the WeldonSpring Conservation Management Area, and the August A. Busch Memorial Conservation Areahas a practice shooting range. Other recreational use of the land includes hiking trails, bird-watching, and a variety of educational conservation activities. The Katy Trail, a MissouriDepartment of Natural Resources park, is a major east-west hiking and bicycling trail along theformer Missouri-Kansas-Texas railroad right-of-way; the trail passes within several hundredyards of the quarry.
A Missouri Department of Transportation road maintenance facility is east of the chemical plantsite (see Figure 4). Approximately 35 employees work at this facility, which houses roadconstruction equipment and equipment repair activities. The Francis Howell High School isapproximately one-half mile east of the chemical plant site (see Figure 4). The high school hasoccupied the site for 33 years. The student/staff population has varied greatly during this periodand currently includes approximately 2,000 individuals.
Two residential areas located approximately 2 to 3 miles east of the chemical plant site, the townof Weldon Spring and the Weldon Spring Heights community, have a combined population ofabout 1,250. The area north of the August A. Busch Memorial Conservation Area supports lowto moderate density residential use, some commercial activity, and a trailer park along Highway40/61. Land west of the Weldon Spring Conservation Management Area is predominantlyfarmland. Also, a limited amount of cattle grazing may occur in this area.
Figure 5 shows population densities (based on 1990 census block estimates). The only residentsin the original boundaries of the 17,000 acre Weldon Spring Ordnance Works are less than tenMissouri Department of Conservation personnel and families at the August A. Busch MemorialConservation Area (see Figure 4). Population densities for census blocks north and northeast ofthe chemical plant site are generally less than 100 residents per block but have been increasing,with some blocks having densities of 500 or more residents.
Available health outcome data include information about the relative frequency of specificillnesses, cancers, causes of death, and the general health status of a community. This publichealth assessment features two uses of health outcome data: (1) to evaluate the frequency ofknown health effects from contaminants at the site to determine whether St. Charles Countyresidents have higher than expected rates relative to state or national rates; (2) to addresscommunity concerns about the occurrence (frequency) of specific diseases by evaluating anddetermining whether St. Charles County residents had contracted those diseases at rates differentfrom state and national rates.
The Missouri Department of Health furnished the following list of available health outcome data.ATSDR epidemiologists evaluated these data only in the context of this public health assessmentand reported all results to the Missouri Department of Health:
- Cancer registry data for all of St. Charles County, by zip code for 1980-91;
- Vital statistics (birth and death records) for all of St. Charles County, by address location, for 1972-92; and
- Birth defects records for all of St. Charles County, by zip code, for years 1980-87.
ATSDR staff members did not receive personal identifiers (e.g., names, addresses) for personsincluded in these data sets. The Missouri Center for Health Statistics published the specific dataitems in each set .
ATSDR completed a Preliminary Public Health Assessment for the Weldon Spring Site,concentrating on the 9-acre abandoned limestone quarry, in 1988 (see Appendix E). Theassessment concluded that the quarry is a public health concern because likely human exposureto on-site gamma radiation poses a significant health risk to persons having access to the quarry. ATSDR recommended additional characterization of the quarry and off-site sampling .
ATSDR completed an Addendum to the Preliminary Public Health Assessment for the WeldonSpring Site, in 1990 (see Appendix E). The addendum responds to a U.S. EnvironmentalProtection Agency (EPA) request for ATSDR to evaluate the health threat posed to U.S. Armyreservists training in designated areas of the Weldon Spring Training Area . This training area contained lead, TNT, and other TNT-related compounds. ATSDR concluded that the lead, TNT,and TNT-related compounds in the designated training areas pose a minimal health risk toreservists and recommended a radiological survey of the designated training areas .
In 1989, in response to an EPA request, the ATSDR Emergency Response Branch conducted ahealth consultation on consumption of fish collected from lakes within the August A. BuschMemorial Conservation Area (see Appendix E). The consultation evaluated concentrations ofheavy metals (arsenic, lead, and mercury) in composite samples of whole fish, cleaned fish(scaled, beheaded, and eviscerated), and fillets of fish . ATSDR concluded that theoccurrence of metals in composite fish samples from these lakes does not present a public healththreat to area residents who have occasional meals of locally caught fish . ATSDRrecommended limiting fish consumption to once per month, collecting additional fish samples,and identifying and educating anglers who fish in these lakes .
In response to another EPA request, ATSDR conducted another health consultation in 1993 onadditional whole fish and fish fillet data collected from Lake 36 within the August A. BuschMemorial Conservation Area (see Appendix E). ATSDR concluded that the levels of arsenic,lead, and mercury in these fish samples did not represent a health threat for either infrequent or subsistence consumption . Additionally, based on the decrease in lead levels from 1988analyses to the 1992 analyses, Missouri Department of Health staff members do not consider anadvisory for these lakes necessary .
In 1993, ATSDR evaluated the public health implications of contaminant clean-up levels thatDOE staff members proposed for remedial action at the site. ATSDR determined that there areno completed chronic exposure pathways for public exposure to contaminated soils at thechemical plant site or in adjacent off-site areas (see Appendix E) . Also, the proposedclean-up levels are protective of public health for accidental or intermittent exposures but wouldnot be protective under any future residential occupancy conditions at the site . Additionally,off-site areas have not been evaluated for non-radioactive soil contamination . ATSDRrecommended that DOE maintain site access restrictions and institutional control, evaluate off-site areas for non-radiologic contamination, and modify dose assessment procedures if the site isreleased for public access .
In 1994, at the request of DOE, ATSDR conducted a health consultation on the human healthhazard posed by the interim remedial action plan for removing bulk wastes from the quarry(Appendix E). As the Record of Decision describes it, the remedial action plan called forremoval of bulk waste from the quarry and transporting the waste to a temporary storage area inthe chemical plant area . ATSDR concluded that the remedial action plan for excavating,transporting, and temporarily storing the quarry bulk waste does not present a potential forpublic exposures to hazardous wastes . The consultation did not identify any specific healthconcerns related to excavating or transporting the bulk wastes but did recommend the use of dustcontrol techniques to minimize worker exposures .
In 1994, in response to a request from local citizens, ATSDR completed a health consultation onpotential exposure of Francis Howell High School students and staff to airborne radionuclidesfrom the chemical plant site (see Appendix E). Results from DOE air monitoring did not indicateany airborne radioactive materials above background concentrations at the school . Also,measurements from monitoring stations at the site boundary and at the high school during sitebuilding demolition (1993 calendar year) did not show any air concentrations of site-relatedcontaminants, including alpha emitting materials (uranium, thorium, etc.), above background. ATSDR concluded that off-site migration of contaminants to the Francis Howell HighSchool was not occurring and that contamination from the chemical plant site does not pose apublic health concern for students and faculty at the school .
ATSDR staff members have made several visits to the Weldon Spring area to meet with sitepersonnel; local, state, and federal officials; and concerned citizens. The first visit was a tour ofthe Weldon Spring Training Area and former Weldon Spring Ordnance Works facility onFebruary 6-8, 1991. ATSDR staff members met with representatives of the U.S. Army, theMissouri Department of Health, and the Missouri Department of Conservation. The second visitto the DOE chemical plant site on June 8-12, 1992, included a tour of the DOE facility andmeetings with representatives of federal and state regulatory agencies, the St. Charles Countyschool administration, and The St. Charles Countians Against Hazardous Waste.
ATSDR staff members attended a December 16, 1992, public hearing sponsored by the DOE andthe EPA, which attracted approximately 150 concerned residents. Twenty-five people presentedspecific comments regarding the "Proposed Plan for Remedial Action at the Chemical PlantArea." Other individuals or group representatives said they would provide written comments tothe DOE and EPA. The Community Health Concerns section of this public health assessmentcontains a list of community health concerns collected at this meeting and other meetings.
ATSDR staff members joined representatives of Boston University in a series of meetings withlocal health officials, St. Charles County government officials, area residents, and members ofThe St. Charles Countians Against Hazardous Waste and the Coalition for the Environment (St.Louis area). These meetings took place May 24-26, 1993, and focused on identifying communityhealth concerns and verifying a list of previously identified concerns. Community concern overpossible exposure to airborne radioactive materials at the Francis Howell High School promptedATSDR to conduct the 1994 health consultation on that issue.
ATSDR staff members attended an EPA-sponsored demonstration of bioremediation of the U.S.Weldon Spring Ordnance Works' soil contaminants during a trip to the site April 5 - 8, 1994.ATSDR staff members also met with representatives of EPA, the Army, and the MissouriDepartments of Health and Conservation. During that visit, ATSDR representatives met withmembers of the public and the medical community to discuss specific health concerns. Publicavailability sessions July 11-12, 1994, at two public schools near the Weldon Spring NPL siteswere an outgrowth of that visit. Approximately 24 members of the community gave ATSDRspecific health concerns.
The community concerns obtained at these site visits and through related telephone conversationsand correspondence fall into two general categories: (1) concerns about exposure to contaminantsand (2) concerns about specific health effects or disease. The following Community HealthConcerns section contains descriptions of these concerns.
We obtained community health concerns from local residents, health care providers, andgovernment representatives in a series of meetings, telephone calls and correspondence. Severalmeetings with representatives of The St. Charles Countians Against Hazardous Waste haveallowed us to verify the resulting list of community health concerns. The community concernsare categorized as concerns about contaminant exposures (Table 1) and concerns about specific health effects (Table 2).
The list of community exposure concerns in Table 1 identifies the areas, times (e.g., past, present,future), and populations of concern. Most exposure concerns involved residents living adjacentor close to the site or exposures occurring in the adjacent conservation areas. Exposure occurringas a result of releases of treated water from site water-treatment plants to the Missouri River andto food crops grown in nearby areas are the only community health concerns that involveresidents outside the Weldon Spring area.
The Environmental Contamination and Public Health Implications section of this public healthassessment addresses the community exposure concerns with evaluations of human exposurepathways. An exposure pathway includes both environmental and human components that lead tohuman exposure. After evaluating the status of each exposure pathway, Agency for ToxicSubstances and Disease Registry (ATSDR) health assessors evaluate the public healthsignificance of completed exposure pathways by determining the likelihood that sitecontaminants will produce adverse health effects.
Most of the community health concerns listed in Table 2 are for different types of cancer. Themost common concern was about higher-than-expected leukemia rates for children of St. CharlesCounty. Residents expressing these concerns did not have any information about the possibleroutes or times of exposure to contaminants for most of the health concerns. No specific healthoutcome concerns appeared for populations outside St. Charles County, although several peopleexpressed concern about contamination of potential drinking water from the Missouri River. TheEvaluation of Community Health Concerns section of this public health assessment addressesthese concerns about specific diseases through evaluations of the likelihood that sitecontaminants will produce a particular disease and whether that disease is occurring at normal orexpected rates for the area.
Many Weldon Spring residents also had concerns about the reliability of the environmentalmonitoring data collected by the U. S. Department of Energy (DOE) and its contractors. ATSDRassessors did not evaluate the reliability of DOE monitoring data as part of this assessment.However, in the past, ATSDR staff members attempted to evaluate the adequacy of DOEparticulate air monitoring at the Francis Howell High School. EPA's National Air and RadiationEnvironmental Laboratory staff said the information provided was not sufficient to allow them todetermine the adequacy of the data . However, based on the information and dataprovided, ATSDR concluded that contamination from WSS and building demolition did not posea public health concern [hazard] for persons at the Francis Howell High School. That conclusionwas based on the following information: the characterization study, which indicates that propertyat the high school is not contaminated; gross alpha measurements, which show that no airbornemigration of alpha-emitting radionuclides is occurring from the site to the high school; and radondata, which indicate that radon emissions from WSS do not contribute to radon exposures at thehigh school .
In addition to collecting community concerns, we released the Public Comment draft of thePublic Health Assessment of the Weldon Spring Quarry/Plant/Pits (USDOE) on September 30,1996. The comment period ended November 29, 1996. During that period, we received onecomment from the public. A summary of the comment and our response is provided in Appendix F.
|Exposure Concerns||Area ofConcern||Time ofConcern||Population ofConcern|
|1) Private, off-site wells: Contamination of private wells bytoxic substances migrating from theWeldon Spring Training Area andchemical plant site.||North (downgrade) oftraining areaand chemicalplant site||Past||Residents andbusinesses withprivate wells|
|2) Fish and game: Ingestion ofcontaminants that havebioaccumulated in fish and gamefrom the conservation areas.||Conservationareas||Past, presentand future||Hunters, fishers,and theirfamilies|
|3) Airborne radioactivity, past: Exposure to airborne releases ofradioactive contamination (includingradon).||Off site||Past||Francis HowellHigh Schoolstudents/staff, Weldon SpringHeightsCommunity andother residents|
|4) Off-site soil: Past and currentexposure to areas of off-site soilcontamination during recreationalactivities in the adjacent conservationareas.||Discrete areaswithin thetraining areaandconservationareas||Past, present,future||Conservationareas visitors andmilitarypersonnel in thetraining area|
|5) Surface water: Past exposure toon-site surface water at the quarryand raffinate pits or off-siteconservation area lakes.||On-site pits/quarry;Off-siteconservationarea lakes||Past||Site trespassers,conservationarea visitors.|
|6) Airborne radioactivity,present/future: Exposure to airbornereleases of radioactive contaminationduring site cleanup for students andstaff of the Francis Howell HighSchool.||Off site||Present, future||Francis HowellHigh Schoolstudents/staff, Weldon SpringHeightsCommunity andother residents|
|7) Incinerator: Construction of an on-site incinerator to dispose ofhazardous materials.||Off site||Future||Francis HowellHigh Schoolstudents/staff,.and other nearbyresidents|
|8) Remedial workers: Site remedialworker exposure to asbestos andother hazardous materials due toinsufficient worker training.||On site||Present, future||Site remedialworkers|
|9) County Municipal Wells: Contamination of the St. CharlesCounty municipal well field by toxicsubstances migrating from the quarry.||Public wellfield downgrade fromquarry||Future||St. CharlesCounty residents|
|10) Missouri River: Contaminationof Missouri River because of releaseof water from water treatment plantsat quarry and chemical plant .||Missouri Riverdownstream ofrelease outfalls||Present, future||Residents of St.Louis County|
|11) Waste storage cell: Potentialreleases of toxic substances from theWeldon Spring waste storage cellbecause of earthquakes or karstdissolution and collapse in limestoneterrain.||North (downgrade) oftraining areaand chemicalplant area||Future||Residents andbusinesses withprivate wells|
|12) Food crops: Crops are grown nextto site and on ; there is concern thatthese crops may be contaminated bysite-related hazardous materials andconsumed by people (According to U.S. Department of Energy staff no oneeats the crops grown on theconservation areas).||Conservationareas andUniversity ofMissouriResearch farm||Past, presentand future||General public|
|Health Outcome Concerns orQuestions||ExposureRoute||Area ofConcern||Time ofconcern||Sub-Populationof Concern|
|Childhood leukemia||Unknown||St. CharlesCounty||Past duringproductionreleases1957-66and cleanup1967-72||Students atFrancisHowellHighSchool andchildrenlivingadjacent tosite|
|Unspecified health effects fromformer workers exposure toradioactive materials||Multipleexposureroutes||On site||Past 1957-66||Siteworkers|
|Renal cell cancer||Unknown||Residentialareasadjacent tosite||Unknown||Arearesidents|
|Alopecia||Unknown||Residentialareas northof site||1980-present||Children|
Potential site hazards due tolocalized concentrations ofexplosive materials at the FormerOrdnance Works
|NotApplicable||Chemicalplant siteand trainingarea; oldwastepipelines||Present andfuture||Siteremedialworkers|
|Unknown means community members did not know about exposure times or areas forspecific medical concerns.|