EPA Superfund Record Of Decision: Perham Arsenic Burial .
EPA Region 5 Records Ctr.205516PB94-964101EPA/ROD/R05-94/247July 1994EPA SuperfundRecord of Decision:Perham Arsenic Burial Site,Perham, MN,3/31/1994
DECLARATION FOR THE RECORD OF DECISIONSITE NAME AND LOCATIONPerham Arsenic Burial SitePerham, MinnesotaSTATEMENT OF BASIS AND PURPOSEThis decision document presents the selected remedial action forthe Perham Arsenic Burial Site, in Perham, Minnesota, chosen inaccordance with the Comprehensive Environmental Response,Compensation, and Liability Act of 1980 (CERCLA) , as amended bythe Superfund Amendments and Reauthorization Act of 1986 (SARA),the Minnesota Environmental Response and Liability Act of 1990(MERLA) , and, to the extent practicable, the National ContingencyPlan (NCP) . The decision is based on the Administrative Recordfor the Perham Arsenic Burial Site. The attached indexidentifies the items which comprise the administrative recordupon which the selection of the remedial action is based.The State of Minnesota has been consulted and concurs with theselected remedial action.ASSESSMENT OF THE SITEActual or threatened releases of hazardous substances from thissite, if not addressed by implementing the remedial actionselected in this Record of Decision, may present an imminent andsubstantial endangerment to public health, welfare, or theenvironment.DESCRIPTION OF SELECTED REMEDYThe selected remedial action for the Perham Arsenic Burial Siteaddresses the source of the contamination by remediation ofgroundwater. The major components of the selected remedialaction include:*Institutional Controls*Recovery Wells*Filtration*Alumina Adsorption*Infiltration Gallery*Municipal Water to Resident
STATUTORY DETERMINATIONSConsistent with CERCLA and, to the extent practicable, the NCP, 40C.F.R. Part 300, the selected remedial action is protective ofhuman health and the environment, complies with Federal and Staterequirements that are legally applicable or relevant andappropriate to the remedial action, and is cost-effective.Theremedy utilizes permanent solutions and alternative treatmenttechnologies to the maximum extent practicable and satisfies thestatutory preference for remedies that employ treatment and reducestoxicity, mobility, or volume as a principal element. Because thisremedy will result in hazardous substances remaining on site abovehealth based levels, the five year review will apply to thisaction.Valdas V. AdamJcusRegional AdministratorDate
TABLE OF CONTENTSTITLEPAGE MO.I.SITE NAME, LOCATION AND DESCRIPTION1II.SITE HISTORY AND ENFORCEMENT ACTIVITIES1III.COMMUNITY RELATIONS HISTORY6IV.SCOPE AND ROLE OF REMEDIAL ACTIVITIES7V.SUMMARY OF SITE CHARACTERISTICS8VI.SUMMARY OF SITE RISKS13VII.DESCRIPTION OF ALTERNATIVES18VIII. SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES. .24IX.THE SELECTED REMEDY27XI.STATUTORY DETERMINATIONS28
LIST OF FIGURESPAGE MO.FIGURE MO.TITLEFIGURE 1SITE LOCATION MAP2FIGURE 2LOCATION OF ARSENIC BURIAL PIT3FIGURE 3ARSENIC ISOCONCENTRATION MAP-SHALLOW9FIGURE 4ARSENIC ISOCONCENTRATION MAP-DEEP10FIGURE 5STRATIGRAPGHIC SEQUENCE12FIGURE 6CONCEPTUAL PLAN OF TREATMENT-ALTERNATIVE 220FIGURE 7CONCEPTUAL PLAN OF TREATMENT-ALTERNATIVE 322ii
LIST OF TABLESTABLE NO.TITLEPAGE MO.TABLE 1TOXIC EFFECTS FOR CHEMICALS OF CONCERN15TABLE 2TOXICITY VALUES FOR CHEMICALS OF CONCERN16TABLE 3SUMMARY OF RISK AND HAZARD CALCULATIONS17TABLE 4COST SUMMARY FOR ALTERNATIVE 221TABLE 5COST SUMMARY FOR ALTERNATIVE 323iii
LIST OF ATTACHMENTSATTACHMENT MO.ATTACHMENT 1MPCA LETTER OF CONCURRENCEATTACHMENT 2RESPONSIVENESS SUMMARYATTACHMENT 3INDEX OF THE ADMINISTRATIVE RECORDiv
DECISION SUMMARYI.SITE NAME, LOCATION AND DESCRIPTIONThe Perham Arsenic Burial Site is located in the southwest cornerof the East Otter Tail County Fairgrounds in Perham, Minnesota.The City of Perham is an agricultural-based village in northwestern Minnesota with a population of 2,086. (See Figure 1).The East Otter Tail County Fairgrounds was used as a mixingstation and as a depository for pure (unmixed) lead arsenate andunused arsenic-based grasshopper bait. In 1947, pure leadarsenate and unused arsenic-based grasshopper bait were buried ina shallow pit in the southwest corner of the fairgrounds.(SeeFigure 2). The shallow pit area, and associated groundwaterplume which emanated from the pit area, are considered the PerhamArsenic Burial Site (site). Adjacent fairground properties areused for community and recreational purposes.The topography around site is flat and gently slopes eastwardtoward the Otter Tail River which is approximately 1.8 miles tothe east. The site surface consists largely of open, grassyfields and dirt roads. Several brick, wood, and aluminumbuildings exist on the site. Subsurface features under the siteare characterized by a massive unit of glacial outwash sands andgravel. In the Perham vicinity, a confining clay unit isreported to exist within the glacial overburden, however, theconfining clay unit was not encountered during drilling at thePerham site.Groundwater in the vicinity of the site flows in an east tosoutheast direction towards the Otter Tail River.The City of Perham uses a municipal well system to supplyresidents with potable water. A total of four municipal wellsare used to supply residential and commercial demands. Two wellsare located in the southern section of the city limits,approximately 1/2 mile due west (hydraulically upgradient withrespect to groundwater) of the site. Two additional municipalwells are located to the north approximately 1/2 to 3/4 milesfrom the site. At the current operating conditions, the municipalwell system is not expected to influence contaminant migration atthe site.II. SITE HISTORY AND ENFORCEMENT ACTIVITYDuring the grasshopper infestation of the 1930s and 1940s, theU.S. Department of Agriculture distributed lead arsenate to beused as grasshopper bait to several counties in the state ofMinnesota. Technical grade lead arsenate was mixed with sawdustand molasses to form the grasshopper bait. The bait wasdispersed around farm fields to prevent crop loss. The EastOtter Tail County Fairgrounds in Perham, Minnesota was a mixing
oSOURCE: U.&G.S. PERHAM, MN-OTTER TAIL CO.7.5 MINUTE SCRIES PHOTORCVISCD 1S73iSCALE 1:24000. ofUTRGURE1SITE LOCATION MAPPERHAM ARSENIC BURIAL SITE
station for the arsenic-laden grasshopper bait. In 1947, leadarsenate and unused grasshopper bait were buried in a shallow pitin the southwest corner of the fairgrounds. It is reported thatbetween 200 and 2,500 pounds of grasshopper bait containing over50 pounds of technical grade lead arsenate is thought to havebeen buried in the pit in burlap bags, wood or other decomposablematerial.Groundwater samples from monitoring wells havequarterly or semi-annually since 1980 by stateagencies. Analytical data does not indicate adecrease nor increase in arsenic concentrationmonitoring began.been collectedand federalsignificantlevels sinceThe following is a chronological summary of the history of thePerham Arsenic Burial Site, including site investigation andremedial activities.1931:The Grasshopper Control Campaign Committee was foundedby the Minnesota Department of Agriculture, Universityof Minnesota Agricultural Extension Service and StateEntomologist.1932:Five hundred railroad cars of arsenic bait weredelivered to 55 of Minnesota's 87 counties.19361947:The U.S. Congress spent 27.3 million on grasshoppercontrol, 1.9 million of which was spent in Minnesota.1947:Grasshopper control was terminated. Remaining leadarsenate and remaining arsenic bait were buried in thesouthwestern corner of the fairgrounds in Perham. Itis estimated that approximately 200 to 2,500 pounds ofgrasshopper bait containing over 50 pounds of technicalgrade arsenic were buried in the pit.1971:Hammers Construction Company purchased land from theCity of Perham and erected an office and a constructionwarehouse, adjacent to the arsenic pit.1972:In May, a 31-foot deep, 1.25-inch I.D. galvanized steelwell was installed for Hammers Construction Company.In June, eleven employees became sick as a result ofdrinking water from the well. Two employees sufferedpermanent effects.In July, water samples were collected for arsenicanalysis from Hammers' well, seven private wells thatwere within 120 to 1000 feet of Hammers' building, andthree municipal wells within 1/2 mile of the site. Themaximum arsenic concentration found in Hammers' well
was 11,800 parts per billion (ppb). The well wascapped and city water was extended to the building.In August, the Minnesota Department of Agriculturecollected soil samples at the burial site. Analyticalresults detected arsenic concentrations up to 12,600parts per million (ppm).In October, the Minnesota Department of Agriculturecollected additional soil samples at the site tofurther define the extent of buried arsenic.1974Minnesota Department of Health continued a semi-annualgroundwater sampling program for private and municipalwells within the site's vicinity.1980:In September, U.S. EPA began soil sampling andmonitoring well installation. The investigationdiscovered that arsenic-contaminated groundwaterextended approximately 600 feet downgradient (east) ofthe burial pit on the fairgrounds. Elevated levels ofsoil contamination were found in a 15 by 40 foot areajust north of Hammers Construction Company's propertyand well.1982:The burial pit was capped with a clay cover to reducethe amount of rainwater infiltration thus reducingleaching of the arsenic.1983:The Minnesota Pollution Control Agency (MPCA) issued aRequest for Response Action (RFRA) to East Otter TailCounty Fairboard and the City of Perham. The site wasincluded on the MPCA's Permanent List of Priorities andon the U.S. EPA's National Priorities List (NPL).1984MPCA completed the first Remedial Investigation/Feasibility Study (RI/FS) for the site. In 1984 thefollowing remedial action was proposed, and in 1985, itwas implemented.1.Excavation of approximately 200 cubic yards ofarsenic wastes and contaminated soils containinggreater than 500 ppm, with subsequent disposal atan approved hazardous waste disposal facility.Backfilling the excavated pit with clean fillmaterial.3.Reestablishment of the clay cap and impermeablemembrane to minimize leaching of any residualarsenic.
4.Continuation of groundwater monitoring untillevels of arsenic in the monitoring wells fellbelow the federal drinking water maximumcontaminant level (MCL) of 50 micrograms per liter(ug/L).After completion of this initial remedial actiongroundwater was expected to attenuate. Groundwatermonitoring has continued on a semi-annual basis to thepresent.1989:The Agency for Toxic Substances and Disease Registry,U.S. Public Health Service, conducted a HealthAssessment for the site and recommended post-remedialsampling of the groundwater to define the extent of thearsenic plume.Because arsenic concentrations in groundwater have notsignificantly decreased, as assumed at the time of the1985 remedial action, the EPA developed a RI/FS WorkPlan to define the extent of the arsenic plume, anddetermine whether residual soil contamination remained.1992/1993EPA conducted a two phase RI of the site, whichincluded the installation of twenty-five (25)monitoring wells and twelve (12) soil borings.The Potentially Responsible Party (PRP) search for the sitelisted several persons and entities who could have exposure underCERCLA 107. However, to date, no general or special noticeletters have been issued.III. COMMUNITY RELATIONS HISTORYSince the discovery of arsenic in Hammers' well, the PerhamArsenic Burial site has been a topic of conversation for thecitizens of Perham. Citizens of Perham, members of Perham'smunicipal government, and civic organizations in Perham wereactive in lobbying the state legislature for passage of aSuperfund law.U.S. EPA and MPCA have kept Perham residents informed of alldevelopments at the site. News releases, news media contact, andmeetings have provided the community with information of variousremedial events throughout the clean up process. Investigationsregarding soil contamination were discussed with city staff andofficials, and members of the Arsenic Action Committee on October11, 1983. When the investigation commenced, MPCA issued a newsrelease on the project, and members of MPCA staff wereinterviewed by local reporters. The City of Perham newspaper,The Enterprise Bulletin, provided frequent coverage of MPCA'sprogress.
7At the conclusion of the first RI/FS in 1984, MPCA held a publicmeeting to discuss investigation results and invite comments onthe proposed remedy to clean up soils. On July 19, 1984,approximately 30 people attended the meeting at which MPCA, U.S.EPA, and MPCA's contractors presented information and respondedto questions. The meeting was covered by regional as well aslocal news media. Fact sheets outlining the results of the RI/FSand the Minnesota Superfund were available at the meeting.On March 31, 1992, U.S. EPA and MPCA personnel visited Perham tomeet with the city manager, city engineer, school districtmembers, county fair board members, newspaper editor, andadjacent property owners. During the meetings attendees wereinformed of the upcoming investigation and the rationale for it.Also, a tentative schedule for completion of the RI/FS, ProposedPlan, public meeting, and Record of Decision was discussed.Meetings with various city and private personnel were held inJuly 1992, February 1993, and January 1994. An RI Fact sheet wasissued explaining the findings of the investigation in January1994.Following completion of the second RI/FS in 1994, the U.S. EPApublished a Proposed Plan for remedial action, on February 15,1994. The RI/FS Report, Proposed Plan for remedial action andthe Administrative Record, have been placed in an InformationRepository located at the Perham Public Library, 100 3rd StreetNE, Perham, Minnesota. Consistent with Section 113 of CERCLA,the Administrative Record includes all documents such as the workplan, data analyses, public comments, transcripts, and otherrelevant information used in developing remedial alternatives forthe site. These documents were made available for public reviewand copying at the Perham Public Library.To encourage public participation in the remedy selectionprocess, consistent with Section 117 of CERCLA, the U.S. EPA seta 30 day public comment period from February 15, through March16, 1994, on the Proposed Plan. A Public Meeting was held onFebruary 22, 1994, to answer questions regarding the ProposedPlan and to accept verbal public comment on the Proposed Plan.Interested parties provided comments on the alternativespresented in the Proposed Plan and elaborated upon in the FS.The remedy for the Perham site described herein was selectedafter a detailed review of public comments received. Theattached Responsiveness Summary addresses those public commentsreceived.IV.SCOPE AND ROLE OF REMEDIAL ACTIVITIESIn 1985, the first remedial action for the site was implemented.Approximately 200 cubic yards of arsenic wastes and contaminatedsoils were excavated and disposed of at an approved hazardouswaste disposal facility. The excavated pit was backfilled withclean fill material. A clay cap and impermeable membrane tominimize leaching of any residual arsenic was installed.Groundwater monitoring was implemented and scheduled to continue
until levels of arsenic in the monitoring wells fell below theMCL.Because the source of arsenic contamination had been removed andsurface water infiltration into the pit area was limited, thearsenic plume was expected to eventually dissipate. Groundwatersamples, which have been collected twice a year since 1984, showthat arsenic contamination has not decreased significantly sincethat time.The RI/FS conducted in 1992/1993 was designed to determine thepresent extent and movement of arsenic contamination in thegroundwater and whether residual levels of arsenic contaminationwere present in the soil. The 1992/1993 RI/FS concluded thatarsenic is present in the groundwater at concentrations rangingfrom below detection limit (2 ppb) to 1260 ppb within a 600 X 400foot plume. (See Figure 3). The vertical extent ofcontamination is approximately 85 feet below grade. (SeeFigure 4) .Residual soil level results indicate that arsenic concentrationsare below published background concentrations for soils inMinnesota. U.S. EPA and MPCA agree that no further action onsoils is necessary.The remedial action selected for the site will eliminate thethreats associated with ingestion and direct contact withcontaminated groundwater. The remedial action, in combinationwith the 1985 remedial action regarding arsenic contaminatedsoils at the site, should be considered a complete site remedy.When this remedial action is completed, no further remedialaction is expected, other than groundwater monitoring. Themonitoring of groundwater would be conducted to assure that thearsenic concentration in groundwater remains below the cleanuplevel. Since the time to achieve the cleanup level is estimatedto take longer than five years, a five year review would benecessary.V.SUMMARY OF SITE CHARACTERISTICSA. Soil ContaminationThe source of contamination at the site was arsenic-ladengrasshopper bait and technical grade lead arsenate buried in apit located in the southwest corner of the East Otter Tail CountyFairgrounds. The arsenic was buried approximately 3 to 6 feetbelow grade. The dimension of the burial pit was 10 by 20 feet.Soils around the pit area also became contaminated with arsenic.The burial pit and surrounding soils are the only confirmedsource of contamination. An additional source was reported underthe Hammers construction company building. During the 1992/1993investigation, borings were completed to determine if residualsoil contamination existed below the pit area and under Hammers'building. Results of the soil investigation indicate that
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11arsenic levels were below published background concentrations forsoils in Minnesota and are not considered a direct contact threator a source of groundwater contamination.Due to the presence of lead in the unmixed lead arsenate, soilsamples were also analyzed for lead. Lead analysis indicatedthat levels found were slightly above background levels in onesoil boring. However, concentrations of lead in that boring didnot pose an unacceptable risk.B. GroundwaterContaminationContaminated groundwater, resulting from water infiltratingthrough the former pit area prior to removal of unmixed leadarsenate and arsenic bait, is the media of concern. Arsenic ingroundwater is at concentrations ranging from below detectionlimit (2 ppb) to 1260 ppb within a 600 X 400 foot plume. Thevertical extent of contamination is approximately 85 feet belowgrade. Analytical results at the site indicated that 99% of thearsenic in groundwater is in the arsenate (As 5) state. Arsenicin this state strongly adsorbs and does not tend to move far.This appears to be the situation at the site. In 46 years, theedge of the plume has migrated approximately 600 feetdowngradient of the initial source.Because lead was in the unmixed lead arsenate, groundwatersamples were analyzed for lead. Concentrations of lead ingroundwater across the site do not indicate a clearly definableplume. However, since lead is site related, it was evaluated inthe baseline risk assessment (BRA) . The BRA determined that leadconcentrations at the site did not pose an unacceptable risk.The groundwater recovery well network will be designed to capturethe arsenic plume. Lead concentrations encompassed within thisplume will be recovered and treated along with the arsenic.Groundwater samples were collected and analyzed for the TargetAnalyte List (TALs), to confirm the presence or absence of otherinorganic analytes. Results indicated that arsenic was the onlycontaminant of concern.C.Geology/HydrogeologySite geology consists of a massive unit of outwash sands andgravels. Thickness of the outwash deposits under the site aregreater than 122 feet below grade.A confining clay unit isreported to exist within the glacial overburden, however, theconfining clay unit was not encountered at the site. (SeeFigure 5).Groundwater in the vicinity of the site flows in an east tosoutheast direction towards the Otter Tail River which isapproximately 1.8 miles to the east of the site. Groundwaterlevels at the site are approximately 22 to 24 feet below grade.
SLMfACC O V. 0»4O'tffSANOAoumSA1UUTEDSP TO SW100*1a.100' o120-140-IALOCADONSOf 1MBCIMTSAHC\ttr AMD ONMFOR1CDLY CA ABU OT SUSTAWMOSUBSTANTIAL OUANTITCS OF ! :OOKST «dt IMUD AT IMC SICIIEICALF & EDDYRGURE 5PERHAM ARSENIC BURIAL SITEPERHAM. MINNESOTAGENERALIZED STRAT1GRAPHIC SEQUENCE
13The glacial outwash aquifer at the site is characterized by fineto coarse sands and gravels, admixed or interbedded, withsporadic silty areas. The sustained yield rating for thisaquifer is estimated to be 100 to 500 gallons per minute.D.Groundwater UseWater supplies obtained from the aquifer present in the Perhamvicinity are used for industry, agriculture (irrigation),municipal, and residential demands for potable water.The nearest residential well currently in use as a domestic watersource is located approximately 700 feet to the south of theformer arsenic pit, perpendicular to the groundwater flowdirection. The well was sampled and analyzed on three separateoccasions during the course of the RI. Arsenic concentrationsdetected in the residual well averaged 6 ppb. Leadconcentrations were below the instrument detection limit. Thebackground concentration for arsenic was determined by analyzinggroundwater samples collected from the upgradient well MEW-8.Background arsenic concentration is 5 ppb. Therefore, arsenicconcentrations in the residential well are at background levels.VI.SUMMARY OF SITE RISKSA. Human RisksInformation contained in the BRA of the RI Report indicates thatcurrent and future potential health risks to individuals at thesite are related to exposure of arsenic contaminated groundwatervia ingestion and dermal contact. A current and futureresidential use scenario was used for arsenic in groundwater.Arsenic is classified as a Group A Human Carcinogen.Concentrations of chemicals of concern (arsenic & lead), on whichthe risk assessment was based, were determined by following U.S.EPA guidance which requires a 95% upper confidence limit on thearithmetic mean, assuming a log-normal distribution. Exposurepoint concentrations were determined by either the maximumconcentration within the contaminant plume, or the 95% upperconfidence limit, which ever was lower. Maximum concentrationsof arsenic from the existing residential well were used as theexisting groundwater exposure source.Exposure pathways considered were ingestion and dermal contactwhile showering with arsenic contaminated groundwater.Potentially exposed populations under the current use scenarioidentified the closest residential well. Under future usescenario, primary receptors were children and adults that wouldreside directly on site and would receive their drinking waterfrom a groundwater well installed on site. Exposure intakevariables used in the risk assessment were selected so that thecombination of all intake variables resulted in an estimate ofthe Reasonable Maximum Exposure (RME) for each pathway.
14Cancer potency factors (CPFs) have been developed by U.S. EPA'sCarcinogenic Assessment Group for estimating excess lifetimecancer risks associated with exposure to potentially carcinogenicchemicals. CPFs, which are expressed in units of (mg/kg-day)-1are multiplied by estimated intake of potential carcinogen(mg/kg-day), to provide an upper-bound estimate of the excesslifetime cancer risk associated with exposure at that intakelevel. The term "upperbound" reflects the conservative estimateof the risks calculated from the CPF. Use of this approach makesunderestimation of the actual cancer risk highly unlikely. CPFsare derived from the results of human epidemiological studies orchronic animal bioassays to which animal-to-human extrapolationand uncertainty factors have been applied.Reference doses (RFDs) have been developed by U.S. EPA forindicating the potential for adverse health effects from exposureto chemicals exhibiting noncarcinogenic effects. RFDs, which areexpressed in units of mg/kg-day, are estimates of lifetime dailyexposure levels for humans, including sensitive individuals.Estimated intakes of chemicals from environmental media (e.g.,the amount of a chemical ingested from contaminated drinkingwater) can be compared to the RFD. RFDs are derived from humanepidemiological studies or animal studies to which uncertaintyfactors have been applied (e.g.,.to account for the use of animaldata to predict effects on humans). These uncertainty factorsassure that the RFDs will not underestimate the potential foradverse noncarcinogenic effects to occur.Excess lifetime cancer risks are determined by multiplying theintake level with the CPF. These risks are probabilities thatare generally expressed in scientific notation (e.g., 1X10-6).An excess lifetime cancer risk of 1X10-6 indicates that, as aplausible upper bound, an individual has a one in a millionchance of developing cancer as a result of site-related exposureto a carcinogen over a 70-year lifetime under the specificconditions at the site.Toxicity value information used in the risk assessment forchemicals of concern at the site are summarized in Tables 1 & 2.The findings of the non-carcinogenic hazard assessmentdemonstrated that the total non-carcinogenic hazard indices forthe future adult and child receptor populations exceed thecriterion value of 1.0, and are above acceptable levels. Resultsindicate that ingestion of arsenic in groundwater is the exposureroute primarily responsible for the increased hazard.Unacceptable cancer risk estimates calculated in the riskcharacterization were associated with ingestion of groundwaterfor both the adult and child future receptor populations.(SeeTable 3).
15Tablel i Critical Toxic Effects for Chemicals of Concern at the Pertain SiteANALYTEArsencNONCARCENO6ENIC EFFECTSINHALATIONORALtomtomNAly wl pr pM Vl IvBUWI 1Leadcentral nervoustoncttycentral nervoustoncty(1) Source: Annual FY-1992 HaaRh Effects Assessment Summary Tables(9 US. EPA Weight of Evidence tor Carcinogens:Group A, Human CarcinogenGroup B, Probable Human CarcinogenGroup C, Possible Human Carcinogen Group 0, Not ClassifiableGroup E. Evidence of Noncarcinogenicit/NA«Not ApplicableCARCINOGENIC EFFECTS (2)ORALINHALATIONskinrMpratory tract(group A)(group A)MANA(group B2)(group 82)
gsIkii91
17Table 3MatrixGroundwaterMatnxI GroundwaterISummary of Risk and Hazard on6.34E-02IHazard2.74E 02!! Dermal5.18E-05I2.24E-0116.35E-02I2.74E eIngestonlOermal2J1E-02I1.42E-05IHazard5 96 -M)2I3J7E-01I2J1E-02ISJ9E-H)2IRiskI
18B. ENVIRONMENTAL RISKSThe ecological assessment in the RI concluded that environmentalimpacts on surface soil (0-2') and subsurface soil (2-10') wereimportant because most exposure to site contaminants would occurthrough soil. Exposure pathways from on site soils involve threeindicator species. Selected indicator species are not expectedto be negatively impacted by contamination on site. Althoughconcentrations of lead exceeded Minnesota background levels, acomparison of ingestion and uptake rates with toxicologicalvalues indicated that the risks associated with lead were at anacceptable level.Conclusions made from site observation during the RI indicatethat no signs of stress on indicator species (grasshoppers) orvegetative stress (yellow sweet clover) were observed.VII.DESCRIPTION OF ALTERNATIVESThe objective of the FS and the Proposed Plan was to evaluateremedial alternatives consistent with the goals and objectivesof CERCLA, as amended by SARA.Health and environmental risks identified in the BRA for thesite provide the basis for establishing the remedial actionobjectives for the site. The BRA indicates that the onesignificant contaminant pathway is exposure associated withingestion of contaminated groundwater. All remedial actionalternatives in the FS involved a combination of extractinggroundwater and various treatment options. A treatabilitystudy was conducted in the RI phase.Results of the studywere used to develop the treatment component of remedialalternatives.A.Alternative 1No ActionIn this alternative, no remedial action would be performed atthe site. No efforts would be undertaken to contain, remove,monitor, or treat contaminants in the groundwater at the site.Evaluation of the no action alternative provides a baselineagainst which action alternatives can be compared andevaluated.B.Alternative 2Institutional Controls, Recovery Wells, Precipitation,Filtration, Alumina Adsorption and an Infiltration GalleryAlternative 2 involves institutional controls (e.g., deedrestrictions), recovery wells, groundwater treatment byprecipitation, filtration, and alumina adsorption, with treatedgroundwater discharge via an infiltration gallery.
19Institutional controls (deed restrictions) would
1932: Five hundred railroad cars of arsenic bait were delivered to 55 of Minnesota's 87 counties. 1936- The U.S. Congress spent 27.3 million on grasshopper 1947: control, 1.9 million of which was spent in Minnesota. 1947: Grasshopper control was terminated. Remaining lead arsenate and remaining arsenic bait were buried in the
Rapid Flow, Titration, Turbidimetry, Ultraviolet- Visible Spectroscopy (UV/VIS) Parameter/Analyte Water pH EPA 150.1 Turbidity EPA 180.1 Calcium EPA 200.7 Iron EPA 200.7 Magnesium EPA 200.7 Potassium EPA 200.7 Silica, Total EPA 200.7 Sodium EPA 200.7 Aluminum EPA 200.8 Antimony EPA 200.8 Arsenic EPA 200.8 .
EPA Test Method 1: EPA Test Method 2 EPA Test Method 3A. EPA Test Method 4 . Method 3A Oxygen & Carbon Dioxide . EPA Test Method 3A. Method 6C SO. 2. EPA Test Method 6C . Method 7E NOx . EPA Test Method 7E. Method 10 CO . EPA Test Method 10 . Method 25A Hydrocarbons (THC) EPA Test Method 25A. Method 30B Mercury (sorbent trap) EPA Test Method .
FALCON REFINERY EPA Publication Date: 7/10/2015 1 FALCON REFINERY SUPERFUND SITE San Patricio County, Texas EPA ID# TXD086278058 Site ID: 0602349 EPA Region 6 State Congressional District: 27 Contact: Brian Mueller 214.665.7167 Updated: July 2015 Current Status
vii References The following resources were used in producing this manual: EPA: Package Treatment Plants MO-12, EPA 430/9-77-005, April 1977 EPA: Summary Report: The Causes and Control of Activated Sludge Bulking and Foaming, EPA 625/8-87/012, July 1987 EPA: Manual: Nitrogen Control, EPA 625/R-93/010, September 1993 EPA: Handbook: Retrofitting POTWs, EPA 625/6-89/020, July 1989
EPA Method 7E –NO, NO 2, NOx Yes EPA Method 8 –SO 2, SO 3 Yes EPA Method 10 –CO Yes EPA Method 11 –H 2 S ( 50 ppm Yes EPA Method 16 –TRS Yes, including mercaptans and other reduced sulphurs EPA Method 18 –VOC’s Yes EPA Method 26 –HCl, HF Yes EPA CTM 027 –NH 3 Yes. ADVANTAGES OF FTIR
EPA/ROD/R10-00/043 2000 EPA Superfund Record of Decision: MIDWAY LANDFILL EPA ID: WAD980638910 OU 01 KENT, WA 09/06/2000
3.4.3. Superfund Sites A Superfund site is any land in the United States that has been contaminated by hazardous waste and identified by EPA as a candidate for cleanup because it poses a risk to human health or the environment.68 Using Superfund and brownfield sites for renewable energy development allo
EPA employees can obtain copies of this guidance, or copies of documents referenced in this guidance, by calling the Superfund Docket at 703-603-9232. Non-EPA employees or members of the public can order a limited number of paper copies of EPA documents at no fee from EPA's National Service Center for Environmental Publications
