PUBLIC HEALTH ASSESSMENT
LINDSAY MANUFACTURING COMPANY
LINDSAY, PLATTE COUNTY, NEBRASKA
The Lindsay Manufacturing site is located in the village ofLindsay, in Platte County, Nebraska. An irrigation systemmanufacturing plant has operated at the site since 1958. Spentacid wastewater was discharged to an unlined surface impoundmentfrom 1971 to 1983. Solvents were discharged into the surfaceimpoundment, and also were dumped onto the ground.
Soils and drainage ditch sediments are contaminated with heavymetals and volatile organic compounds (VOCs) on the LindsayManufacturing site. Ground water is contaminated on-site andoff-site with heavy metals and VOCs. The plume of ground watercontamination extends at least 2,250 feet south-southeast of thesite.
Analyses of exposure pathways for contaminants in on-site soil,drainage ditch sediments, surface water, and air indicated thatsignificant human exposure to contaminants in these pathways isnot occurring, and that these pathways may be eliminated fromfurther analysis. Surface water discharges are negligible, andstreams in the area are intermittent and are not used as sourcesof drinking water. Exposure to soil contaminants and airemissions are unlikely since the area where VOCs were dumped hasbeen paved since 1971.
One potential exposure pathway was identified: the plume ofcontaminated ground water has reached two irrigation wells andone livestock watering well. Agricultural workers may be acutelyexposed to contaminants in the irrigation wells and livestockwatering well via inhalation and dermal absorption. Concentrations of heavy metals and VOCs in the irrigation wellsare below levels that may result in significant bioaccumulationof heavy metals in crops or in food products from livestock.
One completed exposure pathway was identified: the plume ofcontaminated ground water extended to one domestic drinking waterwell. Two VOCs were detected in this well at concentrationsbelow levels that may represent a public health hazard. Residents in the home served by the contaminated drinking waterwell may be chronically exposed to low (insignificant) levels ofthe VOCs via inhalation, ingestion, and dermal absorption. Because of the low levels of contaminants, this pathway may beconsidered of no apparent public health concern. A home watertreatment unit has been installed at the residence to preventexposure to the VOCs.
Estimated doses for VOCs in the irrigation wells, the livestockwatering well, and the domestic drinking water well did notexceed Minimum Risk Levels (MRLs) for noncarcinogenic healtheffects developed by the Agency for Toxic Substances and DiseaseRegistry (ATSDR) or Subchronic Reference Doses developed by theU.S. Environmental Protection Agency (EPA). Some of the VOCs arecarcinogenic in laboratory animals; therefore, human exposure tothese compounds should be minimized.
Lindsay Manufacturing installed two on-site extraction wells in1983 and in 1989 to pump and treat contaminated ground water. Concentrations of contaminants in ground water have been steadilydecreasing since these wells were installed. A third well hasbeen proposed to intercept the off-site portion of the plume. ATSDR concurs with this remedial action since it will preventcontaminants from migrating to the irrigation and drinking waterwells. ATSDR concluded that the Lindsay Manufacturing site posesno apparent public health hazard.
Since humans have been exposed to hazardous substances migratingfrom the site, but concentrations of those substances are belowlevels of public health concern for noncarcinogenic effects, andsince levels of probable human carcinogens detected at humanexposure points were very low, follow-up health activities arenot being considered for this site at this time. However, ifadditional information becomes available in the future indicatingthat significant human exposure to hazardous substances isoccurring or has occurred in the past, ATSDR will evaluate thatinformation to determine whether further public health actions are necessary. EPA will continue to monitor water quality at theresidential water well discussed previously.
The Lindsay Manufacturing site is located in the village ofLindsay, in Platte County, eastern Nebraska. The site consistsof several large manufacturing buildings located along thenorthern border of the village. A surface impoundment is locatedat the northern boundary of the site. Spent acid wastewater wasdischarged to this impoundment from 1971 to 1983. The surfaceimpoundment did not contain a liner during this period. Solventswere also discharged to the impoundment, and were dumped ontosoil at the site. Access to the site is restricted by achain-link fence about eight feet high which surrounds thefacility. The site is connected to municipal water and sewageutilities.
A brief history of the facility is outlined in Table 1 ofAppendix 1. The surface impoundment is regulated under theResource Conservation and Recovery Act (RCRA). TheU.S. Environmental Protection Agency (EPA) has delegatedauthority to operate this program to the State of Nebraska. Since off-site ground-water contamination was identified prior tothe 1984 Hazardous and Solid Waste Amendments to RCRA, the sitewas proposed for the National Priorities List (NPL) under the Comprehensive Response, Compensation and Liability Act (CERCLA)in 1984. The site was placed on the NPL in 1988. ATSDR prepareshealth assessments for all sites placed on the NPL underauthority of the Superfund Amendments and Reauthorization Act of1986. A Record of Decision (ROD) was signed on September 28,1990, by the EPA Regional Administrator. This ROD stated thatthe remedy for cleaning up the site will consist of a pump andtreat groundwater system and a soil vapor extraction pilot studyto determine whether this method is practicable for soil clean-up. The EPA and Lindsay Manufacturing Company entered into aconsent decree which requires Lindsay Manufacturing to design thepump and treat system and to conduct the pilot study. TheDepartment of Justice has not yet signed the consent decree.
A site visit was conducted by a ATSDR regional representative inAugust 1990. The ATSDR representative viewed the LindsayManufacturing site from beyond the property boundary. Nophysical hazards were noted. As groundwater contamination cannotbe seen, as quarterly monitoring data indicates no furthercontamination, and as no subsequent activity has occurred on thesite, ATSDR has determined that additional visits to the site arenot necessary at this time.
During the August 1990 visit, the ATSDR representative alsovisited the home of a citizen whose drinking water well had beencontaminated with hazardous substances migrating from the LindsayManufacturing site. The citizen had no health concerns. Therepresentative then attended a public meeting to discuss the sitewith other representatives of other government agencies and withthe public. The ATSDR representative answered citizens' healthquestions and the representatives of all the various agenciespresent referred citizens with occupational health questions toappropriate state and federal occupational health agencies.
The population of Lindsay was estimated to be 392 in 1986 (1). The population is mostly Caucasian with median socioeconomicstatus. About 58 percent of the population of Platte County isless than 18 years of age or older than 54 (1). Approximately 80percent of the population is employed by Lindsay Manufacturing.
The site itself is bordered on the north by farmland, and on thewest, south and east by residential areas of the village ofLindsay (1). A high school and an elementary school are locatedwithin one-quarter mile of the site. There are no hospitals,health clinics, or long-term health care facilities within twomiles of the site.
Lindsay is located along the eastern boundary of the NebraskaSand Hills Region, and is characterized by rolling hills(dissected loess plains).
Natural resource use consists of farming and pumping ground water for irrigation and for human consumption. The surficial soils consist of silty clay loam, which are underlain by about 30 feet of low-permeability silts and clays that were deposited by wind during the Quaternary geologic period. These deposits are underlain by about 35 to 50 feet of Quaternary sand and gravel deposited by glaciers and streams. The sand and gravel deposits are part of the High Plains Aquifer, and comprise the sole source aquifer for the village of Lindsay. Thirteen irrigation and livestock watering wells, one domestic drinking water well and one public water supply well are located in the High Plains Aquifer within one mile of the site. The sand and gravel deposits are underlain by the Upper Cretaceous Niobrara Limestone, which has low ground water yield, and is not used as a source of drinking water or irrigation water in the area. Surface water is not used for drinking water, swimming, or fishing within two miles of the site (1).
ATSDR has identified the following state and local health datasources as potentially pertinent to this site:
*Nebraska Vital Statistics
*Registries of cancer incidence and mortality in Nebraska
*Registry of birth defects in Nebraska.
The Bureau of Vital Statistics captures the Vital Statisticsinformation; however, the Health Data Support Division of theNebraska Department of Health analyzes the information andgenerates reports based on the data. In addition, the HealthData Support Division collects, analyzes and reports on theinformation for the registries. Information for the cancerregistries is collected by zip-code; however, printouts andanalyses are routinely performed at the county level. The cancerincidence registry covers the years 1987, 1988, and 1989; thecancer mortality registry goes back for several decades. Information for the birth defects registry is collected bycounty. The birth defects registry began in approximately 1975.
Citizens have expressed several concerns to representatives ofEPA and the Nebraska Department of Environmental Controlregarding ground-water quality. At an EPA-sponsored publicmeeting concerning the Lindsay site, citizens and workers at theLindsay Manufacturing plant spoke anonymously and confidentiallyto representatives of government agencies regarding their healthcomplaints. They specifically mentioned cancer and femalereproductive system disorders. A resident whose well is known tohave been contaminated has indicated to representatives of theAgency for Toxic Substances and Disease Registry (ATSDR) that heis concerned about the quality of his drinking water, but had nospecific health complaints. No other concerns have been voicedto any of the above-mentioned agencies. There are no citizens'advocacy groups involved with this site known to the ATSDR.
Volatile organic compounds (VOCs) were dumped onto the ground onthe site, and were also discharged to the unlined surfaceimpoundment along with spent acid wastewater containing heavymetals. These activities resulted in soil and ground watercontamination on the site. Heavy metals and VOCs were alsodetected in sediments in a drainage ditch that discharges throughthe center of the site. Brief descriptions of maximumconcentrations of hazardous substances detected in soil,sediment, and ground water on the site are shown on Table 2 ofAppendix 1. Detailed descriptions of on-site contamination arecontained in the Remedial Investigation/Feasibility Study (RI/FS)prepared by Lindsay Manufacturing for the State of Nebraska (1). No on-site air monitoring has been conducted, but releases to airwould have been limited to volatilization of VOCs from soil andthe impoundment. The soil dumping area was paved in 1971, andVOC releases to the impoundment ceased in 1983. Therefore,on-site air monitoring during the RI/FS was not necessary.
Off-site contamination consists of ground-water contamination inthe High Plains Aquifer. The extent of off-site ground-watercontamination was defined during the RI by installation ofoff-site monitoring wells, sampling off-site drinking water wellsand irrigation wells, and computer modeling of ground-water flowand contaminant transport in the High Plains Aquifer. Theoff-site ground-water contamination plume extends at least 2,250feet south-southeast of the site, and intersects two irrigationwells, one livestock watering well, and one domestic drinkingwater well. The New Lindsay public water supply well is locatedabout 1,200 feet northwest (hydraulically up-gradient) of thesite, and no site contaminants have been detected in that well. Site contaminants were not detected in the former Lindsay publicwater supply well located 300 feet west of the site during theperiod that it was used (1975 to 1983).
Lindsay Manufacturing concluded that contaminants entered thesemi-confined High Plains Aquifer beneath the site throughleaking annuli at monitoring wells installed on the site in 1982. A comparison of ground water monitoring data collected before andafter the 1982-series monitoring wells were installed supportsthis conclusion. Construction details of the 1982-seriesmonitoring wells indicate that annuli were filled with "roadgravel," providing a conduit for contaminant migration to theaquifer.
Maximum concentrations of contaminants detected in off-siteground water are shown on Table 2 of Appendix 1. These resultsare summaries of monitoring conducted from 1977 to 1990. Detailed descriptions of off-site monitoring are included in theRI/FS report (1).
One off-site domestic drinking water well was found to be contaminated with site-related contaminants, although at levels below health concern. These contaminants are 1,1,1-trichloroethane (at a maximum concentration of 0.008 milligrams trichloroethane per liter water [mg/L]) and trichloroethene (0.0006 mg/L).
No off-site soil, surface water, sediment, or air monitoringresults were reported in the RI.
Environmental monitoring samples were collected and analyzedaccording to procedures in standard EPA guidance documents (EPASW-846, EPA 600/4-82-057) from 1983 to 1988. Samples werecollected and analyzed according to EPA Contract LaboratoryProcedures from 1989 to 1990. Data validation and qualityassurance/quality control (QA/QC) reviews were conducted on thesamples collected from 1989 to 1990. No QA/QC problems werenoted in the information reviewed by ATSDR.
No physical or other hazards were presented in the informationreviewed by ATSDR, nor were any physical hazards noted by theATSDR representative during the site visit conducted in 1990.
A pathway consists of a source of contamination, an environmentalmedium to transport the contaminant, a point of human exposure tothe contaminant, a route of human exposure to the contaminantsuch as ingestion or inhalation, and a receptor population. Contaminants detected in the environment on-site and off-site arerelated to pathways components in Table 2 of Appendix 1.
Current human exposure to contaminants in air, subsurface soils,and surface water are unlikely at this site. Although someexposure to volatilized solvents may have occurred in the past,the solvent dumping area was paved in 1971 and human exposure tosolvents in air from dumping probably ceased at that point. Heavy metals were present on-site in the surface impoundment andwere covered by water. The water prevents wind erosion andsubsequent human exposure. High concentrations of heavy metalsshown on Table 2 of Appendix 1 were detected below land surface,where human exposure is unlikely unless the soils are disturbedduring remedial actions in the future. Due to the alkalinenature of the soil, the potential for heavy metals to leach toground water is minimal, unless an acidic solution is applied tothe soil. Concentrations of contaminants detected in drainageditch sediments were very low. Surface water is not used forhuman consumption, swimming, or fishing within two miles of thesite. Discharges to surface water are regulated under a NationalPollutant Discharge Elimination System permit. Therefore, humanexposure to significant concentrations of contaminants in surfacewater or sediments is not likely.
A soil vapor extraction system has been proposed to removecontaminants from on-site soils. This method may be useful inthe sand channel on-site, but since silts and clays have lowpermeability to fluids (such as air, water, and vapors),extraction of contaminated soil vapor in silts and clays on-sitemay prove difficult.
As stated previously, a plume of contaminated ground waterextends from the Lindsay Manufacturing site south to twoirrigation wells and one livestock watering well. Agriculturalworkers may inhale VOCs volatilizing into air from contaminatedwater at the irrigation well and the livestock well, or they maydermally absorb VOCs in water discharging from these wells thatcome into contact with skin. These exposures would probablyoccur intermittently.
Contaminants from the irrigation and livestock wells may comeinto contact with crops and livestock. Concentrations of heavymetals in water pumped from the irrigation wells were belowlevels that would result in bioaccumulation of toxicconcentrations of those metals in crops, according to theNational Academy of Engineering (2). ATSDR evaluated the heavymetals detected in these wells with transfer coefficients listedin the draft EPA Exposure Assessment Methods Handbook. None ofthe transfer coefficients were sufficiently high to indicate thatheavy metals would bioaccumulate in livestock and be passed on tohumans via food products. Based on this information, heavymetals in irrigation water and livestock water should not beconsidered contaminants of public health concern. VOCs detectedin the wells would not be expected to bioaccumulate in crops orlivestock.
Humans are currently being exposed to contaminants from theLindsay Manufacturing site via ground water. A plume ofcontaminated ground water extends from the Lindsay Manufacturingsite south to one domestic drinking water well. Residents atthat home may inhale, ingest, or dermally absorb VOCs dischargingfrom the domestic drinking water well while showering, bathing,cooking with or drinking the contaminated water. However,exposures associated with this pathway are to contaminants atdoses below health concern. Refer to the Public HealthImplications section below for a discussion of why these exposuredoses are considered below health concern.
Lindsay Manufacturing installed two ground-water extraction wellson-site to pump and treat contaminated ground water. Monitoringresults indicate that contaminant concentrations in on-siteground water have decreased significantly since the extractionwells were installed. Lindsay Manufacturing proposed to installa third extraction well off-site to break the ground-waterexposure pathway between the site and the domestic and irrigationwells off-site. After this well begins to operate, humanexposure to contaminants in ground water will eventually cease.
Adverse health effects associated with exposures to specificcontaminants of concern in potential and completed pathways arediscussed below.
Non-carcinogenic and Carcinogenic Health Effects
ATSDR has developed Minimal Risk Levels (MRLs) as comparisonguidelines of contaminant exposure. An MRL is an estimate ofdaily human exposure to a chemical that is likely to be withoutan appreciable risk of deleterious noncancerous effects over aspecified duration of exposure. Noncancerous health effects maybe acute--resulting from a short-term exposure of less than 14days, or chronic--resulting from an exposure over at least ayear's duration. An MRL can correspond to an acute or chronicexposure.
The mere presence of a contaminant does not imply that harm willresult from exposure. A contaminant at a concentration whichwould lead to an estimated exposure at a dose lower than thatchemical's MRL should pose no appreciable public health hazardwith respect to noncancerous health effects.
Cancer is a large group of diseases characterized by uncontainedgrowth and spread of abnormal cells. Cancer cells multiplyuncontrollably, destroying normal cells, and can spread to otherparts of the body (5). A chemical which is capable of causingdamage leading to cancer is called a carcinogen. Some scientistsbelieve there is no safe level of exposure to any carcinogen (6). The latency period, or amount of time between exposure anddisease, may range from years to decades (7). One contaminant ofconcern at this site (tetrachloroethene) has been classified asProbable Human Carcinogens--chemicals which have been shownexperimentally to cause cancer in animals, but evidence for theircarcinogenicity in humans is inadequate. One contaminant ofconcern (1,1-dichloroethene) has been classified as a PossibleHuman Carcinogen--chemicals which have limited experimentalevidence of causing cancer in animals and no evidence of causingcancer in humans. One contaminant of concern (trichloroethene)has inconclusive evidence of causing cancer in animals or humans.
Health Effects By Chemical
Farm workers may be exposed to PCE from water pumped in theirrigation wells via inhalation of PCE volatilized into air orfrom dermal absorption. ATSDR estimated the dose that mightresult from inhalation of PCE that volatilizes from irrigationwater into air assuming that 100 percent of the PCE from oneliter of water volatilizes into one liter of air at the point ofhuman exposure (2). The estimated dose is below the ATSDR MRLfor acute inhalation of PCE. Therefore, noncarcinogenic adversehealth effects would not be expected to occur via inhalation. ATSDR has not developed an MRL for dermal absorption of PCE.
PCE has been classified by EPA as a Probable Human Carcinogen. Animal studies indicate that inhalation of PCE leads to leukemia and liver cancer in rats. The EPA bases its determination that PCE is a Probable Human Carcinogen in part on these animal studies. Currently available information is not sufficient to determine whether PCE causes cancer in humans (8). ATSDR estimated the cancer risk that may result from exposure to PCE volatilized into air at the irrigation wells. The estimated level of risk may be considered negligible.
Agricultural workers may be acutely exposed to 1,1-DCE viainhalation and dermal absorption in the irrigation wells. Theestimated dose that may result from inhalation of 1,1-DCE wasbelow the ATSDR MRL for acute exposure to 1,1-DCE. Therefore,noncarcinogenic adverse health effects would not be expected tooccur via inhalation. ATSDR has not developed an MRL for dermalabsorption of 1,1-DCE.
1,1-DCE has been classified by EPA as a Possible HumanCarcinogen. Human studies have determined no relationshipbetween the occurrence of cancer and exposure to DCE, but studydesigns suffered from severe design flaws. Some animal studiesindicate that inhalation of DCE is associated with an increase inlung and kidney tumors, but other inhalation studies withlaboratory animals have provided negative or inconclusivefindings with respect to the carcinogenicity of DCE (10). ATSDRestimated the level of cancer risk associated with exposure to1,1-DCE in the irrigation well water. The estimated risk ofcancer is very low.
Individuals using a contaminated residential well may be exposedto TCE. The duration of exposure will depend on theeffectiveness of remediation efforts. The estimated dose whichwould result from using water contaminated at the maximum TCEconcentration detected in the well water is below ATSDR MRLs forlong-term exposure via ingestion and inhalation. Therefore,noncarcinogenic adverse health effects would not be expected tooccur. ATSDR has not developed Minimum Risk Levels for dermalabsorption of TCE.
TCE has inconclusive evidence regarding its carcinogenicity. Increased incidences of tumors have been observed in some animalsthat were experimentally exposed to TCE by ingestion orinhalation. Some laboratory studies indicate that some miceexposed to TCE by ingestion developed liver cancer. Additionalstudies in mice suggest that inhalation exposure may result inliver and lung cancer. Yet the TCE studies use questionablemethods and have inconclusive results, making it difficult toconclude that TCE is an animal carcinogen. Furthermore,information currently available is not sufficient to determinewhether TCE causes cancer in humans (9). Until adequateexperimental evidence is available, either from human or animalstudies, we cannot conclude that exposure to TCE is likely tocause cancer.
Residents at the home with the contaminated water well may bechronically exposed to 1,1,1-TCA via ingestion, inhalation, anddermal absorption. The estimated doses that may result fromingestion and inhalation of 1,1,1-TCA in the domestic water wellwere below ATSDR MRLs. Therefore, noncarcinogenic adverse healtheffects would not be expected to occur via ingestion andinhalation. ATSDR has not developed an MRL for dermal absorptionof 1,1,1-TCA.
1,1,1-TCA has not been associated with carcinogenic healtheffects in man or in laboratory animals.
Based on the review of the nature and extent of possibleexposures and on the toxicologic and physiologic possibleoutcomes resulting from those exposures, ATSDR staff havedetermined that there are no plausible adverse health effectsassociated with this site that warrent analysis of health outcomedata. Furthermore, although one completed pathway has beenidentified, the number of people exposed to contaminants via thatpathway is insufficient to allow analysis of available healthoutcome data.
Citizens and workers at the Lindsay Manufacturing plant expressedconcern about the possibility of cancer and female reproductivesystem disorders associated with exposure to site-relatedcontaminants. The estimated risk of cancer associated withexposure to contaminants detected at the site is very low ornegligible. Likewise, adverse female reproductive system effectsare not associated with exposure to contaminants at theconcentrations detected at this site. ATSDR has not reviewed anydata collected in the occupational setting of the LindsayManufacturing plant, as occupational issues are to be taken up bythe State or Federal occupational health agencies. Citizens werereferred to occupational agencies at the August 1990 publicmeeting.
- Based on the information reviewed, ATSDR has determinedthat there are no completed pathways with contaminants atlevels of public health concern. In addition, the EPA hasbegun to pump-and-treat the ground water in extractionwells and ATSDR believes contaminant levels aredecreasing. ATSDR has determined that there is noapparent public health hazard associated with the LindsayManufacturing site.
- Soil and ground water are contaminated on the LindsayManufacturing site due to operation of a unlined surfaceimpoundment and dumping of solvents onto the ground. Ground-water contamination resulting from these activitiesextends off-site.
- Waste disposal activities at the Lindsay Manufacturingsite resulted in one potential exposure pathway (potentialacute exposure to heavy metals and VOCs in two irrigationwells and in one livestock watering well by agriculturalworkers) and one completed exposure pathway (chronicexposure to VOCs in a residential drinking water well). This completed pathway has been determined to be of noapparent public health concern.
- Because of their low concentration, migrating contaminantsdetected off the site are of no apparent public healthconcern.
- As the contaminants are all at levels below that of healthconcern and as the number of people exposed tocontaminants via that pathway is insufficient to allowstatistical analysis of available health outcome data, nostatistical analysis of community-specific health outcomedata is neccesary to indicate whether the site has had anadverse effect on human health.
- Extraction wells have been installed to extract and treatcontaminated ground water. A soil vapor extraction systemhas also been recommended by EPA. Extraction ofcontaminants in soil and ground water will reduce thepotential for exposure to contaminants in the potentialand completed pathways.
- Citizens expressed concerns regarding associations betweenreleases of contaminants from the site into theenvironment and cancer and female reproductive systemdisorders. As discussed previously, the estimated dosesfor contaminants were below ATSDR Minimum Risk Levels fornoncarcinogenic effects, and lifetime cancer risks fromexposure to these contaminants are believed to beinsignificant. No association between exposure tosite-related contaminants and the expressed healthconcerns can be established.
- In accordance with the Comprehensive EnvironmentalResponse, Compensation, and Liability Act of 1980, asamended, the Lindsay Manufacturing Site has been evaluatedfor appropriate follow-up with respect to healthactivities. Humans have been exposed to hazardoussubstances migrating from the site, but concentrations ofthose substances are below levels of public healthconcern. Citizens with concerns about exposures outsidethe workplace have received health education materialsfrom ATSDR representatives. Citizens concerned aboutexposures received in the workplace have been referred tostate and federal occupational health agencies. For thesereasons, follow-up health activities are not beingconsidered for this site at this time. However, ifadditional information becomes available in the futureindicating that human exposure to hazardous substances isoccurring or has occurred in the past at levels of publichealth concern, ATSDR will reevaluate this site for anyadditional indicated follow-up.
- ATSDR concurs with the installation of a third off-sitemonitoring well to intercept contaminants in ground waterbefore they reach the domestic drinking water well andalso concurs with installation of the on-site soil vaporextraction system.
- When indicated by public health needs, and as resourcespermit, the evaluation of additional relevant healthoutcome data and community health concerns, if available,is recommended.
1. Actions Taken:
ATSDR recommends that quarterly monitoring be conducted on thedomestic water well contaminated with VOCs, and concurs that theplume of contaminated ground water should be extracted from theaquifer and treated. These actions are already being conductedby EPA and the State of Nebraska. EPA will continue to monitortreated and untreated water quality in the residential water welldiscussed previously to insure that the water treatment systeminstalled at the home is functioning properly, and to determinewhen water treatment is no longer necessary.
2. Actions Planned:
EPA may incorporate a third extraction well installed by LindsayManufacturing into the Remedial Action Plan.
Since the Lindsay Manufacturing site presents no apparent publichealth hazard, followup health activities are not being plannedby ATSDR at this time. However, if additional environmentalmonitoring or health outcome data become available in the future,ATSDR will review that information and determine whetheradditional public health actions are necessary.
The Lindsay Manufacturing Public Health Assessment (PHA) wasavailable for public review and comment from September 1 throughSeptember 30, 1991. ATSDR received no responses pertaining tothe Lindsay Manufacturing Public Health Assessment.
Joseph L. Hughart, MS, MPH, PG
Environmental Health Specialist
Division of Health Assessment and Consultation
Remedial Programs Branch
Stephanie Prausnitz, MS
Environmental Health Scientist
Division of Health Assessment and Consultation
Remedial Programs Branch
David Parker, MPH, RS
Office of the Assistant Administrator, ATSDR
- Draft Remedial Investigation, Lindsay, Nebraska, by Damesand Moore, March 1, 1990.
- Hazardous Waste Land Treatment, EPA SW-874, Office ofWater and Waste Management, Washington, D.C., September1980.
- Health Assessment Documents, Lindsay ManufacturingCompany, Vols. 1-7, by Ecology and Environment, July 25,1988.
- Health Assessment Guidance Manual (Draft), ATSDR, Atlanta,GA, July 1990.
- American Cancer Society. Answering Your Questions AboutCancer. 71-1MM-Rev.2/84-No.2025-LE. 1984.
- Lu Frank C. Basic Toxicology: Fundamentals, Target Organsand Risk Assessment. Washington: Hemisphere PublishingCorporation, 1985:85.
- Sherman Janette. Chemical Exposure and Disease: Diagnostic and Investigative Techniques. New York: van Nostrand Reinhold, 1988:19.
- Agency for Toxic Substances and Disease Registry.Toxicological profile for tetrachloroethylene. Atlanta,Georgia: ATSDR, 1990.
- Agency for Toxic Substances and Disease Registry.Toxicological profile for trichloroethylene. Atlanta,Georgia: ATSDR, 1989.
- Agency for Toxic Substances and Disease Registry.Toxicological profile for 1,1-dichloroethane. Atlanta,Georgia: ATSDR, 1989.
|1958||Sprinkler manufacturing begins on-site.|
|1971||Spent acid disposal pit began to be used.|
|1971||Solvent dumping area on-site paved over.|
|1975||Lindsay public water supply well west of site began operation.|
|1977||Samples collected from 3 off-site wells.|
|1980||"Old Well" monitoring well installed west of pit.|
|1981||Samples collected from "Old Well" monitoring well on-site. No contamination detected.|
|1982||82-series monitoring wells installed.|
|1982||Contaminants leak through annuli of 82-series wells to aquifer.|
|1983||Samples collected from "Old Well" monitoring well on-site. Evidence of ground-water contamination detected.|
|1983||Samples collected from 3 off-site wells.|
|1983||On-site interceptor well installed to extract contaminated ground water.|
|1983||Lindsay public water supply well west of site ceased operation. No contamination detected in monitoring from 1983 to 1987.|
|1983||New Lindsay public water supply well northwest of site began operation.|
|1983||Last discharge to unlined spent acid disposal pit.|
|1983||Liners placed in spent acid disposal pit.|
|1984||Site proposed for National Priorities List.|
|1984||Interceptor well began pumping.|
|1987||82-series monitoring wells plugged to prevent further ground-water contamination.|
|1988||Site reproposed for National Priorities List.|
|1989||Second on-site interceptor well installed to extract contaminated ground water.|
|1990||Draft Remedial Investigation/Feasibility Study Developed.|
|1990||Third interceptor well proposed to collect off-site contamination.|
|1990||Record of Decision signed, Consent Decree entered to Department of Justice.|
|Cadmium||On-site soil. |
|On-site ground water.||8.4 mg/L ||None. |
|Off-site ground water.||0.02 mg/L||Irrigated crops.||NA||NA||NA||NA||Bioaccum unlikely.|
|Chromium||On-site soil.||20.4 mg/kg ||45 ft below surface.|
|On-site sediments.||1.1 mg/kg|
|On-site ground water.||2.35 mg/L|
|Off-site ground water.||Below MCL|
|Iron||On-site soil. ||21591 mg/kg||33 ft below surface.|
|On-site sediments.||9879 mg/kg|
|On-site ground water.||5400 mg/L|
|Off-site ground water.||513 mg/L||Irrigated crops.||NA||NA||NA||NA||No bioaccum in crops.|
|On-site sediments.||65.8 mg/kg |
|On-site ground water.||3.4 mg/L|
|Off-site ground water.||Below MCL|
|On-site ground water.||81.6 mg/kg|
|Off-site ground water.|
|Zinc||On-site soil. ||6840 mg/kg|
|On-site sediments.||4881 mg/kg|
|On-site ground water.||8000 mg/L|
|Off-site ground water.||35.9 mg/L||Irrigated crops.||Ingestion||NA||Zinc is phytotoxic below |
human toxicity levels.
|On-site ground water.||165000 mg/L|
|Off-site ground water.||3970 mg/L||Irrigated crops.||Ingestion||Acute|
|PCE||On-site soil.||6.8 mg/kg||38 ft below surface.|
|On-site sediments.||0.1 mg/kg|
|On-site ground water.||1.2 mg/L|
|Off-site ground water.||0-0.380 mg/L||Air (irrigation). ||Inhalation. ||Acute ||0.000125 ||1-ppm-MRL||Minimal |
|1,1,1-TCA||On-site soil.||14.1 mg/kg ||32 ft below surface.|
|On-site sediments.||2.1 mg/kg||18-43 ft below surface|
|On-site ground water.||6.5 mg/L|
|Off-site ground water.||0-0.2.1 mg/L||Residential well.||Ingestion||Chronic||0.0008||0.09 mg/kg/d-RfD||Below comparison value|
|(Max. 0.008 mg/L)||Inhalation||Chronic||0.0000038||0.3 mg/kg/d-RfD||Below comparison value|
|1,1-DCE||On-site soil.||1.9 mg/kg||13-38 ft below surface|
|On-site sediments.||.008 mg/kg||42 ft below surface.|
|On-site ground water.||1.6 mg/L|
|Off-site ground water.||0.006-0.280 mg/L||Air (irrigation).||Inhalation.||Acute||0.000092||0.09 ppm-MRL||Air concen. assumed to be 0.00028 mg/cu m (7.06E-05 ppm).|
|1,1-DCA||On-site soil.||0.4 mg/kg ||18 ft below surface.|
|On-site ground water.||0.14 mg/L|
|Off-site ground water.|
|Toluene||On-site soil.||0.033 mg/kg||45 ft below surface.|
|On-site sediments.||0.008 mg/kg||At land surface.|
|On-site ground water.||0.13 mg/L|
|Off-site ground water.||ND|
|TCE||On-site soil. ||"< 0.05 mg/kg" ||13-18 ft below surface|
|On-site ground water.||0.012 mg/L|
|Off-site ground water.||0.0006 mg/L||Residential well||Ingestion.||Chronic||0.00006||3.0-Intermed MRL|
|Inhalation||Chronic||0.000000288||0.3 ppm-Acute |
|Air concen. assumed to |
be 6.0E-07 mg/cu m