WS-3967 _13231_CA_RMR_20221230_MMPE Report

TABLEOFCONTENTS

EXECUTIVESUMMARY..................................................................................................1
1.0INTRODUCTION.....................................................................................................2
2.0SITEHISTORY.........................................................................................................4
2.1UNDERGROUNDSTORAGETANKINFORMATION................................................................4
2.2SITEHISTORY.............................................................................................................4
3.0RISKCHARACTERIZATION......................................................................................6
4.0RECEPTORINFORMATION.....................................................................................6
4.1WATERSUPPLYWELLS................................................................................................6
4.2PUBLICWATERSUPPLIES.............................................................................................6
4.3SURFACEWATER........................................................................................................6
4.4WELLHEADPROTECTIONAREAS.....................................................................................6
4.5DEEPAQUIFERSINTHECOASTALPLAINPHYSIOGRAPHICREGION..........................................7
4.6SUBSURFACESTRUCTURES............................................................................................7
4.7LANDUSE.................................................................................................................7
5.0SITEGEOLOGY&HYDROGEOLOGY........................................................................7
6.0SOILINVESTIGATION.............................................................................................7
7.0GROUNDWATERINVESTIGATION..........................................................................9
7.1MONITORINGWELLINSTALLATION.................................................................................9
7.2MONITORINGWELLSAMPLING.....................................................................................9
7.3GROUNDWATERGAUGING&FLOWDIRECTION..............................................................10
7.4FREEͲPHASEPETROLEUMPRODUCT..........................................................................10
7.5MONITORINGWELLANALYSES....................................................................................10
7.6DESCRIPTIONOFCURRENTGROUNDWATERPLUME.........................................................11
8.0MNA&SOURCEDEPLETION................................................................................15
9.0ASSESSMENTSUMMARY.....................................................................................16
10.0RECOMMENDATIONS......................................................................................17
11.0LIMITATIONS...................................................................................................17

PageI

TABLEOFCONTENTS
(Continued)

FIGURES:
1. USGSTopographicMap
2. SiteMap
3. ReceptorSurveyMap
4. SoilCrossSectionLocationMap
5. SoilCrosssectionAͲA’
6. SoilCrossSectionBͲB’
7. PotentiometricSurfaceMap(10/04/2022)
8. BenzeneIsoconcentrationMap(10/04/22)
9. TolueneIsoconcentrationMap(10/04/22)
10. EthylbenzeneIsoconcentrationMap(10/04/22)
11. XylenesIsoconcentrationMap(10/04/22)
12. MTBEIsoconcentrationMap(10/04/22)
13. GroundwaterCrossSectionLocationMap
14. GroundwaterCrosssectionAͲA’
15. GroundwaterCrosssectionBͲB’


TABLES:
1. USTInformationonPage2
2. RiskBasedSoilAnalyticalResults(April2021)
3. RedLabTPHSoilResults(Sept2021)onPage8
4. MonitoringWellConstructionDetails
5. GroundwaterGaugingData
6. GroundwaterAnalyticalResults(2022)
7. HistoricalGroundwaterAnalyticalResults
8. MMPEPerformanceResults(AugͲSept)2022


APPENDICES:
A. SignedePATAforMMPEEvent
B. 1995CSA&Soil&GroundwaterMaps&Data
C. StandardFieldProcedures
D. RedLabsData(Sept2021)
E. WellRecords(MWͲ7,MWͲ8,MWͲ9,MWͲ10)
F. LaboratoryReportforGroundwaterSamples
G. BenzeneConcentrationsOverTime–MWͲ1
H. LPTMMPEPerformanceReport
I. VaporͲPhasePetroleumHydrocarbonMassRemovalCalculations
J. LaboratoryResultsforAirSamples
K. EstimatedVaporͲPhaseGasolineMassRemovalCalculations

PageII

GreensboroChildren’sMuseumͲFormerGateCityMotorCo.–GroundwaterMonitoring&MMPEReport1
PyramidProject#2022Ͳ11712/30/2022
GROUNDWATERMONITORINGREPORT
GREENSBOROCHILDREN’SMUSEUM–DEQ#13231

EXECUTIVESUMMARY

OnbehalfoftheGreensboroChildren’sMuseum(GCM),PyramidEnvironmental&
EngineeringP.C.(Pyramid)hascompletedtheGroundwaterMonitoringReportforthe
FormerGateCityMotorCompanysite.Thesiteislocatedat220N.ChurchStreetin
Greensboro,GuilfordCounty,NCandisthesiteofapetroleum(gasoline)underground
storagetank(UST)release.TheUSTreleasewasdetectedin1995duringtheremovalof
theformergasolineUSTsystemsanddispenserislandsatthesite.TheNCDepartment
ofEnvironmentalQuality(NCDEQ)assignedDEQIncident#13231totheGateCityMotor
site.ThelocationofthesiteisshownonFigure1,aportionoftheGreensboro,NC,
USGStopographicmap.

ThesitewaspreviouslyownedbyGateCityMotorCompanywhooperatedtwo4,000Ͳ
gallongasolineUSTsatthesite.TheUSTswereremovedbyPyramidinJanuary1995,
alongwith110cubicyardsofpetroleumcontaminatedsoil(approximately165tons).
PostͲexcavationsoilsamplesshowedthatthepetroleumcontaminationpersisted
outsidetheinitialexcavationarea.Soilandgroundwaterassessmentwascompletedfor
thesitebyothers,andtheassessmentshowedanoffͲsiteincidenttotheeast.
Between1998andJune2020severalgroundwatersamplingeventswereconductedon
theproperty,andMWͲ1continuedtoshowelevatedbenzenelevelsabovetheGross
ContaminantLevels(GCLs).Intheearly2000s,GateCityMotorCompanydonatedthe
propertytotheGreensboroChildren’sMuseum(GCM).

InJune2020,theNCDEQsentaregulatorylettertoGateCityMotorsattheGreensboro
Children’sMuseum(GCM)addressconcerningtheUndergroundStorageTank(UST)
incident#13231.TheNCDEQrequiredcontinuationofthepriorworkforgroundwater
assessmentandremediationatthesite.TheNCDEQletterstatedthatmanyofthe
previousgroundwatermonitoringwellshadbeenabandoned,andthatadditional
assessmentwasrequired.The2020benzeneconcentrationdetectedinMWͲ1was
aboveNCGrossContaminantLevel(GCL)forbenzene(>5,000ug/L).

AfterdiscussingthesitewiththeNCDEQthesitewasnotyet“Directed”tocomplete
assessmentsincethesiterankingwasintermediaterisk.PyramidworkedwithGateCity
MotorCompanyandGCMtotransfertheTrustFundEligibilityforthesitefromGate
CityMotorCompanytoGCM.ThelettertransferringtheNCTFEligibilitytoGCMwas
receivedinJanuary4,2021anddesignatedGCMastheResponsibleParty.Thisdecision
wasagreeduponbybothpartiesasthemostworkablelongͲtermsolution.

GreensboroChildren’sMuseumͲFormerGateCityMotorCo.–GroundwaterMonitoring&MMPEReport2
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InNovember2020,theNCDEQTrustFundloweredthefundingleveltoincludeall
IntermediaterankedsitesliketheGCMsite.ThisallowedGCM/Pyramidtosubmita
PreͲApprovalforthesitetoprovideadditionalassessmentfortheformerUSTarea.
Sincethattime,Pyramidhasbeenconductingassessmentactivitiesatthesiteinorder
tomoveIncident#13231towardsregulatoryclosure.

InAugust/September2022,atthedirectionoftheNCDEQ,PyramidcompletedaweekͲ
longMMPEeventatthesite.Thepurposeoftheeventwastoactivelyremovethe
petroleumhydrocarbonsatthesiteinordertobringthebenzeneconcentrationsto
belowtheGrossContaminantLimitof5,000ug/LinMWͲ1.AcopyofthesignedePATA
isincludedinAppendixA.

1.0INTRODUCTION

ThegasolinepetroleumUSTreleasedetectedattheGCMsiteoccurredinthe
downtownurbanareaofGreensboroNC.Therearenosensitivereceptorsnearthesite,
andnowatersupplywellsarelocatedwithin1,000feetofthesite.Thesiteislocated
immediatelytothewestoftheDukePowerFormerManufacturedGasPlant(MGP#2).
ThisMGPsiteisunderreviewandassessmentthroughtheNCDEQSuperfundSection,
anditsimpactonthesitewillbediscussedlaterinthisreport.

TheformerautoservicecentercontainedtwogasolineUSTsystemswhichwere
removedin1995.TheUSTswereownedandoperatedbyGateCityMotorCompany
whowastheresponsiblepartyatthetimeoftheUSTremovalandassessmentinthe
1990s.
Table1ͲFormerGateCityMotorsUSTInformation

Intheearly2000sGateCityMotorsgiftedthepropertyandbuildingstotheGreensboro
Children’sMuseum(GCM).TheNCDEQRequiredadditionalassessmentand
remediationatthesitein2020,andthetransferoftheTrustFundEligibilitywas
arrangedfromGateCityMotorstotheGreensboroChildren’sMuseum(GCM).From
nowon,GCMisactingastheresponsibilitypartfortheUSTincidentandclaimingTrust
FundreimbursementfortherequiredUSTassessmentandremediation.

Tank
No.
Install
Date
Sizein
Gallons
Tank
Dimensions
Last
Contents
AdditionalComments
T119764,00064”’dia.x24’LGasolineConfirmedrelease–Removed1995
T219764,00064”dia.x24’LGasolineConfirmedrelease–Removed1995

GreensboroChildren’sMuseumͲFormerGateCityMotorCo.–GroundwaterMonitoring&MMPEReport3
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SiteInformation:
GroundwaterIncident#: DEQ#13231
ResponsibleParty:GreensboroChildren’sMuseum
ReleaseDate:01Ͳ04Ͳ1995duringUSTremovals
110CubicYards(165tons)ofsoilremoved
SiteName:FormerGateCityMotorCompany
SiteAddress:220N.ChurchSt.,Greensboro,NC27401
County:GuilfordCounty,NC
SourceofGPSlocation:GoogleEarth
GPSLocation:FormerAutoServiceGasolineUSTSystems
Latitude/LongitudeofSource:N36.074473°/WͲ79.785834°

USTOwner/USTOperator:BruceW.Benton/GateCityMotorCo.
300N.ChurchStreet,Greensboro,NC

ResponsibleParty:GreensboroChildren’sMuseum
220N.ChurchStreet,Greensboro,NC

PropertyOwner:GreensboroChildren’sMuseum

PropertyOccupant:GreensboroChildren’sMuseum

ConsultantContractor:MikeJones,OperationsManager
PyramidEnvironmental&Engineering,PC
503IndustrialAve.,Greensboro,NC27406
(336)335Ͳ3174
[e-mail]

AnalyticalLaboratory:PaceAnalyticalServices,LLC
9800KinceyAve.,Suite300
Huntersville,NC28078
(615)258Ͳ5858

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2.0SITEHISTORY

2.1UndergroundStorageTankInformation
Asdescribedearlier,thetwogasolineUSTswereusedattheformerautoservicecenter
locatedasshownonFigure1andFigure2.Basedontheavailableinformation,the
USTsweresingleͲwalledsteelUSTsinstalledinthelate1960s,andthedetailsofthe
USTsaresummarizedinTable1.TheUSTsystemswereremovedinJanuary1995,and
subsequentsoilresultsshowedcontaminationremainedintheUSTarea.TheNC
DepartmentofEnvironmentalQuality(NCDEQ)assignedDEQIncident#13231tothe
GateCityMotorsite.Additionalassessmentandremediationwerecompletedinthe
1990sfollowingtheUSTremoval.

Althoughnotonthesubjectproperty,thepriorconsultantidentifiedtwoheatingoil
tankslocateddirectlytotheeastanddowngradientoftheGCMgasolineUSTs.Thetwo
offͲsiteUSTswerereportedlyusedtofuelboilersonthedowngradientproperty.
AppendixBpresentsaportionofthe1995ComprehensiveSiteAssessmentwhich
includesabriefdescriptionoftheDukePowerMGP#2sitelocatedontheadjoining
propertytotheeastoftheGCMsite.TheheatingoilUSTswerelocateddirectlytothe
eastofthegasolineUSTs,andthe1995reportshowed1.74feetoffreeͲphase
petroleumproductinMWͲ6whichwaslocatedoffͲsite.ThelocationoftheoffͲsiteUSTs
andMWͲ6areshownonFigure2.

2.2SiteHistory
TheGateCityMotorservicecenterwasformerlylocatedat200NorthChurchStreetin
Greensboro,GuilfordCounty,NC.TwoUSTsystemsconsistingoftwo4,000Ͳgallon
unleadedgasolineUSTsandassociatedpipingwereexcavatedandremovedfromthe
siteonJanuary4,1995.LaboratoryanalysisofsoilsamplescollectedbeneaththeUSTs
detectedTotalPetroleumHydrocarbon(TPH)concentrationsbetweennonͲdetectand
6,056milligramsperkilogram(mg/kg)inexcessoftheNCActionLevels.TheNCDEQ
requestedadditionalassessmenttoincludeaComprehensiveSiteAssessment(CSA).

AfterreceivinglaboratoryconfirmationofthepetroleumreleaseinJanuary1995,the
USTͲ61FormwascompletedforthesiteandsenttotheDEQtodocumenttherelease.
TheNCDEQassignedincidentnumber#13231totherelease.InFebruary1995,aNotice
ofRegulatoryRequirement(NORR)wassenttoGateCityMotorsrequestingassessment
oftheUSTrelease.InMay1995,MWͲ1wasinstalledonthepropertyandsoilborings
wereconducted.


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InNovember1995,aComprehensiveSiteAssessment(CSA)wascompletedfortheGate
CityMotorsite.Aspartoftheassessment,soilsampleswerecollectedfromfoursoil
boringsatthesite.Four(4)typeIIshallowgroundwatermonitoringwells(MWͲ2,3,4,&
5)andtwo(2)typeIIIdeepmonitoringwells(DWͲ1&2)wereinstalledontheproperty.
GroundwateranalyticalresultsindicatedthatbenzenelevelsinMWͲ1wereaboveGross
ContaminantLevels(GCLs)forgroundwater.SoilanalyticalresultsshowedTPH
concentrationsaboveNCDEQActionLevels.

InJuly1996,aCorrectiveActionPlan(CAP)reportwassubmittedtotheNCDEQ.The
reportrecommendedthatnaturalattenuation/passiveremediationbeimplementedat
thesite.

InMarch1998andJune1998additionalgroundwatersampleswerecollectedfromthe
siteforlaboratoryanalyses.Subsequently,groundwatersampleswerecollectedand
analyzedinJune2001andOctober2002,focusingonMWͲ1.Thesesamplingevents
showedthatonlybenzeneexceededtheGCLsinMWͲ1atthesite.

In2003,aMobileMultiͲPhaseExtraction(MMPE)eventwasconductedontheproperty.
Fluidsandvaporswereextractedfromthesiteforatotalof96hours.Theevent
removed9.01gallons(55.98pounds)ofpetroleumhydrocarbonsfromthesite.

Between2003and2019onlyonegroundwatersamplingeventwasconductedonthe
propertyinMarch2011.TheeventconsistedofsamplingMWͲ1.Laboratoryanalysis
indicatedconcentrationsofbenzeneat5,990ug/LwhichwasstillabovetheGCL.

TheJune9,2020,groundwatersamplefromMWͲ1showed10,300ug/Lbenzenewhich
iswellovertheNCAC2LGroundwaterStandardandGCLsforbenzene.

InSeptember2021,Pyramidcollectedsoilandgroundwatersamplesatthesite.Atrack
mountedGeoprobe™wasusedtoinstalltwomonitoringwells(MWͲ9andMWͲ10)to
20feetBLSusingaugers.TheSeptember2021groundwatersampleshowed7,610ug/L
benzenewhichisovertheNCACGroundwaterStandardsandGCLsforbenzene.

TheNCDEQrequestedactionsforthesitefromGateCityMotorsattheGreensboro
Children’sMuseum(GCM)addressconcerningtheUSTincident#13231

GreensboroChildren’sMuseumhasacceptedresponsibilityfortheUSTreleasecanhas
acceptedtheNCTrustFundEligibilityforthesitefromGateCityMotors.Thecurrent
rankingofthesitewaslistedasintermediate(IͲ75ͲR).

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3.0RISKCHARACTERIZATION

TheLSARiskClassificationandLandUseFormwascompletedbytheNCDEQonMay15,
1995,andthesitewasinitiallyranked50/E.InOctober2003,thesitewasreͲrankedby
theNCDEQasanintermediaterisksite(IͲ75ͲR).

Sinceareceptorsurveyhadnotbeenconductedinthelast25years,Pyramid
researchedthesurroundingpropertieswithin1,000feetofthesite.Pyramidperformed
adrivingandwalkingsurveyofthearealookingforwatersupplywells.Theresultsof
the2021receptorsurveyindicatethattherearenoactivewatersupplywellslocated
within1,000feetofthesourcearea(MWͲ1).Surfacewaterfromthesiteisdirectedto
stormwaterdrainsandditchesandeventuallyflowsintoMuddyCreeklocated
approximately1,200feeteastͲnortheastofthesite.Nosurfacewaterislocatedwithin
500feetofthesite.AcopyoftheReceptorSurveyMapisincludedasFigure3.

4.0RECEPTORINFORMATION

InMarch2021,PyramidcompletedthereceptorsurveyupdatefortheformerGateCity
Motorsite.Thepropertiessurroundingthesiteareallretailorcommercialproperties.
ThesiteisintheCityofGreensboro,andtheCityprovidesmunicipalwatertoall
propertieswithin1,000feetofthesite.AvisualsurveywasconductedinMarch2021
anddidnotindicatethepresenceofwatersupplywellswithin1,000feetofthesite.
Figure3isamapofthesurroundingareashowingthe1,000Ͳfootradiusaroundthe
petroleumplume.

4.1WaterSupplyWells
AsshownonFigure3,nowatersupplywellswereidentifiedwithin1,000feet.

4.2PublicWaterSupplies
Thesubjectsiteandallpropertieswithin1,000feetofthesiterelyonmunicipalwater
providedbytheCityofGreensboro.

4.3SurfaceWater
SurfacewaterfromthesitedrainstoditchesandintoMuddyCreeklocated
approximately0.36mileseastͲnortheastofthesite.Thereisnosurfacewaterwithin
500feetofthesite.

4.4WellheadProtectionAreas
Therearenodesignatedwellheadprotectionareaswithin1,500feetofthesite.

GreensboroChildren’sMuseumͲFormerGateCityMotorCo.–GroundwaterMonitoring&MMPEReport7
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4.5DeepAquifersintheCoastalPlainPhysiographicRegion
ThissiteisnotintheCoastalPlain;therefore,thissectiondoesnotapplytothissite.

4.6SubsurfaceStructures
AshallowtelecommunicationslineislocatedcrossingtheformerUSTareaandisnot
expectedtoaffectthespreadofpetroleumcontamination.

4.7LandUse
Theareasurroundingthepropertyisprimarilycommercial.


5.0SITEGEOLOGY&HYDROGEOLOGY

Pyramidreviewedthe1985GeologicMapofNorthCarolinaforinformationconcerning
localgeologyandhydrogeology.Basedonthisreview,thesiteisinthe
CarolinaSlateBeltofNorthCarolina.Thesurfacegeologyconsistsofregionalsoils
createdbytheweatheringoftheunderlyingbedrock.Accordingtothe1985Geologic
MapofNorthCarolina,theunderlyingbedrockbeneaththesiteincludes
metamorphosedgraniticrock,mapsymbolCZg.

Ingeneral,bothsurfaceandgroundwaterflowdirectionsarecontrolledbytopographic
contoursoflandforms,withflowoccurringperpendiculartothecontoursfromhighto
lowelevations.Thesiteelevationisapproximately810Ͳ820feetabovemeanseaͲlevel.
Surfacewaterfromthesiteisdirectedintostormdrainsandditchesandeventually
flowsintoMuddyCreeklocatedapproximately1,200feeteastͲnortheastofthesite.The
locationofthesiterelativetosurfacewaterisshowninFigure1.

6.0SOILINVESTIGATION

SoilsamplingwascompletedaspartoftheGCMassessmentintheareaspreviously
identifiedascontainingthehighestpetroleumconcentrations.Twosoilborings(GPͲ1
andGPͲ2)wereadvancedtoadepthof15feetintheformerUSTareausingatrack
mountedGeoprobe™.DuetotheelevatedPhotoionizationDetector(PID)readings
wheninstallingMWͲ8,andthelimitednumberforsoilanalysespreͲapprovedbythe
NCDEQ,soilsampleswereanalyzedfromGPͲ2andMWͲ8.Thesampleswereshippedto
PaceAnalyticalinHuntersville,NCforlaboratoryanalysis.Thesampleswereanalyzed
forTotalPetroleumHydrocarbons(TPHs)andMADEPVolatilePetroleumHydrocarbons
(VPHs).StandardproceduresusedbyPyramidareincludedinAppendixC.

GreensboroChildren’sMuseumͲFormerGateCityMotorCo.–GroundwaterMonitoring&MMPEReport8
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AnalyticalresultsforsoilfromGPͲ1showednocompoundsaboveResidentialMaximum
SoilContaminantConcentrations(MSCC);however,C5ͲC8andC9ͲC12Aliphatics,nͲ
butylbenzeneandnͲpropylbenzeneexceededsoilͲtoͲgroundwaterMSCCsinGPͲ1.

InMWͲ8atadepthof17.5feetto20feetBLS,resultsshowedC5ͲC8andC9ͲC12
AliphaticsC9ͲC10Aromatics,ethylbenzene,isopropylbenzene,naphthalene,nͲpropyl
benzene,toluene,1,2,4Ͳtimethlybenzene,1,3,5Ͳtrimethylbenzene,andtotalxylenesat
concentrationsthatexceededthesoilͲtoͲgroundwaterMSCCs.Theresultsfromthe
April2021soilsamplingaresummarizedonTable2.

HistoricalsoildatafromNovember1995tankpullreportwerealsoreviewed.Soil
samplescollectedfromunderthetankpitfollowingtheinvestigationrangedfrom356
mg/kgto6,056mg/kgTotalPetroleumHydrocarbons(TPH).

HistoricalsoildatafromNovember1995,ComprehensiveSiteAssessment(CSA)were
alsoreviewed.ThehistoricaldataindicatedelevatedlevelsofTotalPetroleum
Hydrocarbons(TPH)inBͲ1,SBͲ2andMWͲ3.AcopyofthesoildatafromtheNovember
1995CSAisincludedinAppendixB.

Thesoilanalyticalresultsindicatethatpetroleumhydrocarbonsarestillpresentinthe
smearzoneandbelowthewatertableatthesite.Acrosssectionlocationmapis
includedasFigure4.CrosssectionsAͲA’andBͲB’showthecurrentandhistoricalsoil
dataandarepresentedasFigures5&6.

DuringtheinstallationofMWͲ9andMWͲ10,twosoilsampleswerecollectedand
analyzedforGasolineRangeOrganics(GRO)andDieselRangeOrganics(DRO).The
resultsofthesamplingareshownonTable3below.ThelabreportfortheRedLab
samplesisincludedinAppendixD.
Table3
SoilAnalysisofMWͲ9&MWͲ10(September2021)

SampleIDDateGRO(mg/kg)DRO(mg/kg)
MWͲ95’9/28/202129.6190.4
MWͲ107.5Ͳ10’9/28/202191.796.3
NCActionLimit50100

ResultsfromtheRedLabanalysesindicatethatthereisstillpetroleumcontamination
presentinthesoilsatconcentrationsthatexceedNCActionLimitsforbothGROand
DRO.TheseresultswerenotriskͲbasedanalysesandareexpectedtobebelowthe
eventualUSTclosurestandardofIndustrial/CommercialMSCCs.


GreensboroChildren’sMuseumͲFormerGateCityMotorCo.–GroundwaterMonitoring&MMPEReport9
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7.0GROUNDWATERINVESTIGATION

Thegroundwaterassessmentandremediationwerecompletedusingseveral2Ͳinch
diametershallowanddeepergroundwatermonitoringwells.ManyoftheoriginalMWs
wereabandonedduringdevelopmentintheearly2000sandthedeepwellswere
specificallyrequestedtobeabandonedbytheNCDEQ.

7.1MonitoringWellInstallation
Tofurtherinvestigatecurrentgroundwaterconditions,inMarch2021,MWͲ7andMWͲ8
wereinstalledatthesite.LaterthatyearinSeptember2021,twoadditional
groundwatermonitoringwells(MWͲ9&MWͲ10)wereinstalledatthesiteasdirected
bytheNCDEQ.Thewellswereinstalledtoadepthof20feetbelowlandsurface(BLS),
andthewelllocationsareshownonFigure2.Thewellswereconstructedusing15feet
of2ͲinchdiameterscheduleͲ40PVC0.010Ͳinchslottedscreen,andtheremaining
portionofthewellswasconstructedofschedule40PVCsolidwellcasing.Thesoil
boringlogsandwellconstructionrecordsarepresentedinAppendixE.TheMonitoring
welldetailsarepresentedasTable4.

7.2MonitoringWellSampling
SAMPLINGDATE:10/4/2022
WELLSGAUGED:MWͲ1,MWͲ7,MWͲ8,MWͲ9&MWͲ10
WELLSSAMPLED:MWͲ1,MWͲ8,&MWͲ10
FREEPRODUCT:AheavysheenofproductwasobservedinMWͲ8nearest
totheformeroffͲsitefueloilUSTs.
TABLES:Table5:GroundwaterElevationData
FIGURES:Figure2:SiteDetailMap
Figure7:PotentiometricSurfaceMap(10/4/2022)
FIELDPROCEDURES:FieldprocedureswereperformedasoutlinedintheDEQ
July15,2008,andMay1,2012,updatespublication
“GuidelinesforSampling”undertheUSTSection
(AppendixC)


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7.3GroundwaterGauging&FlowDirection
OnAugust29,2022,eachofthefivemonitoringwellsMWͲ1,MWͲ7,MWͲ8,MWͲ9&
MWͲ10weregaugedforgroundwaterelevationandfreeͲproduct.Thetopofcasing
elevationsweresurveyedtoestablishrelativeelevationsusingMWͲ1asareference
pointatanelevationof100.00feet.Therelativetopofcasingelevations,groundwater
gaugingdata,andgroundwaterelevationsareshowninTable3.Amapwasprepared
usingthe2022relativegroundwaterelevationstoindicategroundwatermovementand
ispresentedasFigure7.Thegroundwaterflowdirectionisgenerallytotheeastand
northeast.Thegroundwaterflowdirectionisconsistentwiththedatafrom1995.


7.4FreeͲPhasePetroleumProduct
Althoughnotonthesubjectproperty,thepriorconsultantidentifiedtwoheatingoil
tankslocateddirectlytotheeastanddowngradientoftheGCMgasolineUSTs.Thetwo
offͲsiteUSTswerereportedlyusedtofuelboilersonthedowngradientproperty.
AppendixBpresentsaportionofthe1995ComprehensiveSiteAssessmentwhich
includesabriefdescriptionoftheDukePowerMGP#2sitelocatedontheadjoining
propertytotheeastoftheGCMsite.TheheatingoilUSTswerelocateddirectlytothe
eastofthegasolineUSTs,andthelocationoftheoffͲsiteUSTsandMWͲ6areshownon
Figure2.ThepresenceofsignificantfreeͲproductintheareadoesnothelpin
identifyingtheminoramountsoffreeͲproductfoundonthesite.

OnAugust29,2022,MWͲ8wasgauged,andaheavysheenoffreeproductwas
observedinthebailer.ThepresenceofpetroleumfreeͲproductatthesiteinMWͲ8and
theanalysisofthetypeoffreeͲproductwasverifiedbylaboratoryanalysis.Thelocation
ofMWͲ8isdowngradientofthegasolineUSTs,andneartheoffͲsiteheatingoiltankson
theDukePowerMGPsite.TheheatingoiltankswereinvestigatedandtheoffͲsite
downgradientwell(MWͲ6)showed1.74feetoffreeͲphasepetroleumproductin1995.
ViewingtheareaoverthefencenosignoftheMWͲ6wasobserved.

7.5MonitoringWellAnalyses
LABANALYSES:Selectedwells–EPAMethod6200B
Allgroundwaterconcentrationsarereportedinmicrogramsperliter(μg/L)
TABLES:Table5:GroundwaterMonitoringWellAnalyticalResults
FIGURES:Figure7:PotentiometricSurfaceMap(10/04/2022)
Figure8:BenzeneIsoconcentrationMap(10/04/2022)
Figure9:TolueneIsoconcentrationMap(10/04/2022)
Figure10:EthylbenzeneIsoconcentrationMap(10/04/2022)

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Figure11:XylenesIsoconcentrationMap(10/04/2022)
Figure12:MTBEIsoconcentrationMap(10/04/2022)

GROUNDWATERLABORATORYREPORT&CHAINͲOFͲCUSTODY:AppendixF

7.6DescriptionofCurrentGroundwaterPlume
ThegroundwateranalyticalresultsfromMWͲ1showedbenzeneaboveNCGross
ContaminantLevels(GCLs).Thegroundwaterconcentrationsdetectedaresummarized
onTable6andthelaboratoryreportispresentedinAppendixF.Historical
groundwaterdatasummarytablesaresummarizedonTable7.Theresultsofthe
groundwatersamplingaresummarizedbelow.

x GroundwaterresultsfromMWͲ1containedconcentrationsofbenzeneof5,590
ug/LwhichisabovethebenzeneGCL.Concentrationsoftoluene,ethylbenzene,
xylenes,MTBE,IPE,naphthalene,and1,2,4ͲtriͲmethylbenzeneweredetected
belowGCLsandaboveNCAC2Lgroundwaterstandards.Asheenoffreeproduct
wasshowninMWͲ1duringthesamplingevent.

x GaugingMWͲ8showed1/16thofaninchoffreeproductinthebailer.The
groundwaterconcentrationsinMWͲ8showedbenzene,toluene,xylenes,
naphthalene,and1,2,4ͲtrimethylbenzeneaboveNCAC2Lstandards.Theproduct
hasattributesofgasolineandtoalesserdegreefueloil.

x Theupgradientwell,MWͲ7showednopetroleumcompoundsingroundwater
duringthelastsamplingeventinSeptember2021.

x ThedeepwellDWͲ2wasabandonedwithcementgroutattherequestofthe
NCDEQ.Thisdeeperwellshowedalmostnoverticalmigrationofthepetroleum
compoundsbenzene(8.6ug/L)andMTBE(170ug/L)whenlastsampledin1995.

Benzene
CURRENTMAXIMUMBENZENE:5,590μg/L(MWͲ1)(10Ͳ2022)
PREVIOUSMAXIMUMBENZENE:7,610μg/L(MWͲ1)(09Ͳ2021)
HISTORICALMAXIMUMBENZENE:17,000μg/L(MWͲ1)(10Ͳ2002)
BenzenewasdetectedaboveGrossContaminantLevelsinMWͲ1andabove2L
StandardsinMWͲ8&MWͲ10.

Toluene
CURRENTMAXIMUMToluene:  6,800μg/L(MWͲ8)(10Ͳ2022)
PREVIOUSMAXIMUMToluene:  2,480μg/L(MWͲ1)(09Ͳ2021)
HISTORICALMAXIMUMToluene:  10,300μg/L(MWͲ1)(03Ͳ1998)

GreensboroChildren’sMuseumͲFormerGateCityMotorCo.–GroundwaterMonitoring&MMPEReport12
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Toluenewasdetectedabove2LstandardsinMWͲ1,MWͲ8&MWͲ10.

Ethylbenzene
CURRENTMAXIMUMEthylbenzene: 1,940μg/L(MWͲ1)(10Ͳ2022)
PREVIOUSMAXIMUMEthylbenzene: 2,680μg/L(MWͲ1)(09Ͳ2021)
HISTORICALMAXIMUMEthylbenzene:14,000μg/L(MWͲ1)(10Ͳ2002)
Ethylbenzenewasdetectedabove2LstandardsinMWͲ1&MWͲ8.

TotalXylenes
CURRENTMAXIMUMXylenes:9,930μg/L(MWͲ2)(10Ͳ2022)
PREVIOUSMAXIMUMXylenes:5,950μg/L(MWͲ2)(09Ͳ2021)
HISTORICALMAXIMUMXylenes:9,930μg/L(MWͲ2)(10Ͳ2022)

Totalxylenesweredetectedabove2LstandardsinMWͲ1,MWͲ8&MWͲ10.

MTBE
CURRENTMAXIMUMMTBE:3,080μg/L(MWͲ1)(10Ͳ2022)
PREVIOUSMAXIMUMMTBE:2,010μg/L(MWͲ1)(09Ͳ2021)
HISTORICALMAXIMUMMTBE:97,000μg/L(MWͲ1)(10Ͳ1995)

MTBEwasdetectedabove2LstandardsinMWͲ1&MWͲ10,andshowsthatthe
detectedcontaminationisfromagasolinesource.

Overthepast25years,theconcentrationsofbenzeneinMWͲ1havefluctuatedwith
thechangingwatertabledepth.Typically,asthedepthtowaterincreases,sodothe
concentrationsofbenzeneandotherpetroleumcompounds.Mechanismsdrivingthe
fluctuationsarechangesinwaterlevelwithintheshallowaquifer,rainwaterrecharge
anddilution,naturalattenuation,andotherfactors.Thegraphofthebenzene
concentrationsdetectedinMWͲ1overtimeispresentedinAppendixG.

8.0FREEͲPRODUCT/MMPEEVENT

AsignificantamountofpetroleumHydrocarbonMasshasbeenremovedinthevaporͲ
phaseextractionusingtheMMPEEvents.Additionalremediationisrequiredtoreach
theremediationgoalof>5,000μg/Lbenzenedissolvedingroundwaterandtomaintain
concentrationsbelowthislevelforfourquarterlysamplingevents.Petroleum
hydrocarbonmassremovalisrequiredtoreachregulatoryclosureforthissite.


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Thegasolinesource/hydrocarbonmassremovalrequirescapillaryfringecontamination
removalneartheformergasolineUSTsource.Atotalof5,403gallonsofpetroleum
contaminatedwaterhasbeenrecoveredafteroneMMPEevent.Atotalof10.5gallons
offreeproductequivalentasvaporshasbeenrecoveredduringthisMMPEEvent.The
vaporrecoveryisincludedinthefreeͲproducttotalsfortheevents.

5.1MMPEEvent
OnAugust29,2022,PyramidandLubePump&TankSystems(LPTSystems)mobilized
toGreensboroChildren’sMuseumtoconductthefirstMMPEeventatthesite.Priorto
theMMPEevent,nomeasurablefreeproductwasobservedinMWͲ8.Atthetimeofthe
MMPEevent,benzeneconcentrationsinMWͲ1wereaboveGrossContaminantLimits
(GCLs).

TheMMPEeventwasconductedusingmonitoringwellMWͲ1,MWͲ8andMWͲ10.The
extractionstingersweresetinMWͲ8at12feet,andthestingersweresetinMWͲ10and
MWͲ1at10feet.Thevacuumrecoverycommencedat12:30p.m.onAugust29,2022.
Vacuumwasmaintainedat22Ͳ26inchesofmercury(Hg),withanairflowrateofover
100cubicfeetperminute(cfm)throughouttheevent.Measurementsofsystemand
recoveryparametersweremadeseveraltimesperdayoverthedurationoftheevent.
TheMMPEeventwasterminatedat12:30p.m.onSeptember2,2022,after96
continuoushoursofoperation.

Duringthe96ͲhourMMPEevent,atotalof5,403gallonsofwaterwasrecoveredfrom
MWͲ1,MWͲ8andMWͲ10.Thisrepresentsanaveragerecoveryrateof56.28gallonsper
houror0.938gallonsperminute(gpm)fortheevent.Todate,thetotalvolumeof
groundwaterremovedfromthesiteis5,403gallonsincluding10.5gallonsoffree
product.TheMMPEresultsarepresentedinTable8,includingthedurationofthe
event,themonitoringwellsusedforextraction,thetotalgallonsofgroundwater
removed,thetotalhydrocarbonsremovedasgasolinevaporsandthetotalgallonsof
freeͲproductremoved.

MWͲ8showed1/16thofaninchoffreeproductinthebailerimmediatelyafterthe
MMPEevent.AsummaryoftheMMPEfieldparameters(LPTSystemsReport)is
includedinAppendixH.Acopyofthewastedisposalmanifestfortherecovered
petroleumͲimpactedwaterisincludedinAppendixH.


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FieldparameterscollectedduringtheMMPEeventwereusedtocalculatethetotal
amountofhydrocarbonsremovedasvaporsduringtheevent.Thecalculationswere
performedinaccordancewiththeNCDEQͲUSTSectionGuidelinesforAssessmentand
CorrectiveAction,AppendixB,PagesBͲ74toBͲ75(2005).Aspreadsheetsummarizing
thesecalculationsisincludedinAppendixI.TheOVMreadingsofexhaustvapors
averaged436ppmfortheMMPEevent.TheOVMreadingsbeganwithofreadingof800
ppmatstartͲupandstartedtodecreaseat12:00p.m.onthefirstdayoftheevent.The
OVMreadingattheendofthe96ͲhourMMPEeventwas387ppm.

DuringthisMMPEevent,PyramidalsocollectedthreeairsamplesforVOCandTPH
analysisusingEPAMethod18.Theairsampleswerecollectedatthebeginning
(Monday),middle(Wednesday),andend(Friday)oftheMMPEeventtohelpcalculated
thevaporͲphasepetroleummassremoved.TheairsampleswereanalyzedusingEPA
Method18,andthelaboratoryreportareincludedinAppendixJ.Thecalculated
amountofhydrocarbonsremovedwas51.78pounds.AcopyoftheAirSampling
calculationsareincludedinAppendixK.

ThecalculatedtotalhydrocarbonsremovedasgasolinevaporsfortheAugust2022
eventwasapproximately10.5gallons.TheMMPEresultsarepresentedinAppendixI,
includingthedurationoftheevent,themonitoringwellsusedforextraction,thetotal
gallonsofgroundwaterremoved,thetotalhydrocarbonsremovedasgasolinevapors,
andthetotalgallonsoffreeͲproductremoved.TheMMPEeventshaveremoveda
significantmassofpetroleumhydrocarbonsatthisgasolinecontaminatedsite.

5.2OnͲSiteDischarges
TherearenoonͲsitedischargesoftreatedgroundwater,freeͲproduct,orother
remediationprocesses.ThefluidsgeneratedduringtheMMPEeventweretransported
offͲsiteforpropertreatmentanddisposal.

5.3ExplanationofCleanupGoals&FreeͲProductRecoveryCost
Thesiteisclassifiedasintermediateriskrequiringgroundwatercleanuptobelowthe
GrossContaminantLevels(GCLs).TheremovaloffreeͲproductandcleanupofthe
capillaryfringeor“smearzone”arerequiredtomeettheSiteRemediationGoalsof

1. NoFreeͲphasePetroleumproductinanyMWsforayear,and
2. AlldissolvedgroundwaterconcentrationsbelowGCLSforayear


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Todateatotalofone(1)MMPEeventshavebeencompletedatthesite.FreeͲproduct
andhighlevelsofpetroleumcontaminationhavebeenrecoveredfromtheUSTsystem
areas.Atotalof5,403gallonsofpetroleumcontaminatedwaterandmorethan10.5
gallonsoffreeproducthavebeenrecoveredafteroneMMPEevent.Thevaporrecovery
isincludedinthefreeͲproducttotalsfortheevents.Theinformationconcerningthe
freeͲproductandgroundwaterrecoveryeventsweresummarizedonTable8(DEQ
Format8A).

5.4FreeProductRecovery
TheNCDEQCorrectiveActionBranch(CAB)focusesremediationonthefollowinggoals:

1. FreeͲProductrecoveryto<¼inchinallwellsisalsoaconditionofregulatory
closure.AtGreensboroChildren’sMuseum,thisregulatoryclosurecondition
hasbeenmetwith<¼inchfreeͲproductintheMWs;althoughfreeͲproductis
observedinMWͲ8.

2. GroundwatercleanuptobelowtheGCLsisalsorequired.Thisgoalhasnotbeen
achievedduetohighconcentrationsofbenzeneinMWͲ1,thereforeactive
remediationshasbeencompleted.Theconcentrationshavebeenloweredand
gasolinehydrocarbonmasswasremovedduringtheMMPEevent.Continued
remediationisrequiredtocompletethesitecleanup.

ThefreeͲproductrecoverycompletedattheGCMsitehashelpedreducesoiland
capillaryfringecontaminationaswellasgroundwaterconcentrations.Additional
remediationisrequiredtoreachthefinalcleanupgoals.Pyramidhasdiscussedthesite
withDEQandrecommendsadditionalsoilandgroundwaterassessmentintheformer
USTsourceareatosupportcleanupdecisionmaking.

8.0MNA&SOURCEDEPLETION

TheremedialoptionselectedforthesiteclosurestrategywasMonitoredNatural
Attenuation(MNA).After25yearsofMNA,theconcentrationsinMWͲ1arestillabove
theGCLs.TheappearanceoffreeͲproductinMWͲ8andbenzeneconcentrationsabove
GCLsinMWͲ1indicatethatremediationisrequiredforthisgasolinepetroleumsite.The
presenceoffreeͲproductinMWͲ8suggeststrappedfreeͲproductinthecapillaryfringe
downgradientoftheformergasolineUSTarea.After25yearsofMNA,thesiteneeds
activeremediationtoachieveregulatoryincidentclosure.

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9.0ASSESSMENTSUMMARY

AsrequestedbyGreensboroChildren’sMuseum(GCM),Pyramidhascompletedthe
GroundwaterMonitoring&MMPEReportfortheformerGateCityMotorssite.A
summaryoftheassessmentresultsispresentedbelow.
x InJanuary2021,theNCDEQissuedaTrustFundEligibilitytransferlettertoGCM.
ThiseffectivelymakestheGCMtheresponsiblepartyforthepetroleumrelease,
andallowsGCMtoclaimreimbursementfundsfortheDEQDirectedsite
assessment,remediation,andclosurecosts.

x InMarch2021,Pyramidcompletedareceptorsurveyfortheproperty.
Inspectionoftheurbanareasurroundingthesiteshowednowatersupplywells
arepresentintheareawithin1,000feetofthesourcearea.Also,nosurface
waterispresentwithin500feetofthesourcearea.

x ThereisanothercontaminatedsiteadjoiningtheGCMsitewhichistheDuke
PowerMGP#2sitelocatedapproximately30feeteastoftheformergasoline
tanksontheGCMsite.ThissiteismanagedbytheNCSuperfundSection.

x SoilAnalyticalResultsfromtheMarch2021soilinvestigationindicatethat
petroleumhydrocarbonsarebelowresidentialMSCCstandardsandremain
abovesoilͲtoͲgroundwaterMSCCsinsoilsatGPͲ1andMWͲ8.

x ThefreeproductinMWͲ8wasanalyzedandappearstobefromagasoline
source.

x FromAugust29throughSeptember2,2022,a96ͲhourMMPEeventwas
conductedatthesiteusingMWͲ1,MWͲ8andMWͲ10.Theeventsuccessfully
removedatotalof10.5gallonsofVaporͲPhasepetroleumproductfromthesite,
aswellas5,403gallonsofpetroleumcontaminatedgroundwater.

x FollowingtheMMPEEvent,aheavysheenoffreeproductwasdetectedinMWͲ
8,and0.09feet(1.08inches)offreeͲproductreturnedtoMWͲ8afterthe
MMPEevent.

x DissolvedgroundwaterconcentrationsaftertheMMPEEventshowedbenzene
overGrossContaminantLevels(GCLs)inMWͲ1.

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10.0RECOMMENDATIONS

BasedonthelonghistoryofbenzenegroundwaterconcentrationsdetectedinMWͲ1
overtheGCLs,andthedetectionoffreeͲproductinMWͲ8,Pyramidrecommendsthe
following:
x Pyramidrecommendsconductingadditional96ͲhourMMPEeventsextracting
fromMWͲ1,MWͲ8,andMWͲ10.Theeventswillhelpremediatethegasoline
contaminationinthecapillaryfringeandhelpmovethesitetowardsNCDEQ
regulatoryincidentclosure.

PyramidwillprepareaTrustFundReimbursementClaimPackagewithGCMforthis
directedassessmentwork,andapreͲapprovalforadditionalsiteremediationatthe
GCMSite.


11.0LIMITATIONS

ThisreportispreparedforandmadeavailablesolelyfortheuseofGreensboro
Children’sMuseumandtheNCDEQ.Thecontentsthereofmaynotbeusedorrelied
uponbyanyotherpersonwithouttheexpresswrittenconsentandauthorizationof
PyramidEnvironmental&Engineering,P.C.(Pyramid).Thescopeofservicesforthis
environmentalreportreliesondocumentedenvironmentaldataprovidedbyothers.
TheNCDEQacceptedthepreviousenvironmentalinvestigations;therefore,these
reportsarecountedasreliableinprovidinghistoricaldatafortheevaluationsinthis
report.Thesubsurfaceisinherentlyheterogeneousandsubsurfaceheterogeneitiesnot
identifiedinthislimitedstudymayinfluenceCOCsinunpredictedways.Subsurface
conditionssuchasgroundwaterflow,groundwaterelevations,andwaterqualitywill
varyovertime.Theopinionsandconclusionsinthisreportareinaccordancewith
industryacceptedgeologicandhydrogeologicpracticesusedatthetimeandlocation
wherethereportwasprepared.Nowarranteeisimpliedorintended.Theobservations,
conclusions,andrecommendationsdocumentedinthisreportarebasedonsite
conditionsandinformationreviewedatthetimeofPyramid'sinvestigation.Pyramid
appreciatestheopportunitytoprovidethisenvironmentalservice.















FIGURES


Site Map2















Tables


Industrial Soil to
MW-8 17.5-20 GP-1 7.5-10 Commercial Residential Groundwater
Sample Date:4/1/2021 4/1/2021 MSCC MSCC MSCC
Sample Depth (feet):17.5-20'7.5-10'(mg/kg)(mg/kg)(mg/kg)
VPH & EPH (mg/kg)
C5-C8 Aliphatics (x)VPH 694 228 24,528 939 68
C9-C12 Aliphatics (a)VPH 430 92.7
C9-C18 Aliphatics (b)EPH ND ND 4,000 1,500 540
C9-C18 Aliphatics (a-c)+b Sum 243 67.5
C19-C36 Aliphatics (y)EPH ND ND 81,000 31,000 CI
C9-C10 Aromatics (c)VPH 187 25.2
C11-C22 Aromatics (d)EPH ND ND 12,264 469 31
C9-C22 Aromatics (c+d)Sum 187 25.2
EPA Method 8260 (mg/kg)
Acetone 8260 ND ND 360,000 14000 24
Benzene 8260 0.869 ND 164 18 0.0056
Bromobenzene 8260 ND ND No MSCC No MSCC No MSCC
2-Butanone 8260 ND 3.97 No MSCC No MSCC No MSCC
n-Butylbenzene 8260 2.81 5.02 16,350 626 4.3
sec-Butylbenzene 8260 ND 2.42 16,350 626 3.3
tert-Butylbenzene 8260 ND 0.0179 16,350 626 3.4
Carbon disulfide 8260 ND ND 40,880 1564 4.3
4-Chlorotoluene 8260 ND ND No MSCC No MSCC No MSCC
Ethylbenzene 8260 15.9 0.139 40,000 1560 4.9
Chlorobenzene 8260 ND 0.134
2-Hexanone 8260 ND ND 16,000 6200 1.9
Isopropylbenzene 8260 2.54 ND 40,880 1564 1.7
p-Isopropyltoluene 8260 ND 0.917 No MSCC No MSCC No MSCC
Iodomethane 8260 ND ND No MSCC No MSCC No MSCC
4-methyl 2-pentanone 8260 1.170 1.95 No MSCC No MSCC No MSCC
Naphthalene 8260 6.31 0.101 8,176 313 0.16
n-Propylbenzene 8260 8.84 6.61 16,350 626 1.7
Styrene 8260 ND ND 81,760 3,128 1.5
Trichlorofluromethane 8260 ND ND 122,640 4692 29
1,2,3-Tricloropropane 8260 ND ND No MSCC No MSCC No MSCC
Toluene 8260 16.1 ND 32,000 1200 4.3
1,2,4-Trimethylbenzene 8260 46.4 ND 20,440 782 8.5
1,3,5-Trimethylbenzene 8260 14.7 ND 20,440 782 8.3
Total Xylenes 8260 58.5 ND 81,760 3129 4.6
MTBE 8260 ND ND 3100 350 0.091
All Other 8260 Parameters 8260 NA NA NA
mg/kg = parts per million (ppm).BOLD values exceed the Soil to GW MSCCs
ND = Not detected above the Laboratory Quantitative Limits
NAP = Not Analzyed for this parameter MSCC = Maximum Soil Contaminant Concentration
CI = Considered Immobile 3567 Highlighed Values are > Residential MSCCs
220N.ChurchStreet,Greensboro,NC
NCDEQIncident#13231
NA = Not Applicable
Analytical Parameter Method
TABLE2
RiskͲBasedSoilAnalyticalResults(April2021)
Sample Number
Monitoring Well Well Riser Screen Grout Bentonite Sand Date
Well Depth Diameter Interval Interval Interval Interval Interval Constructed
(feet) (inches) (feet) (feet) (feet) (feet) (feet)
MW-1 30 2 0-15 15-30 0-2 2-13 13-30 Unknown
MW-2 20 2 0-5 5-20 0-2 2-3 3-20 7/6/95 &7/7/95
MW-3 21 2 0-13 13-21 0-2 2-11 11-21 7/6/95 &7/7/96
MW-4 22 2 0-8 8-22 0-2 2-6 6-22 7/6/95 &7/7/97
MW-5 20 2 0-5 5-20 0-2 2-3 3-20 09/14/95
MW-6** 24 2 0-13 13-23 0-2 2-11 11-24 Unknown
MW-7 20 2 0-5 5-20 0-2 2-4 4-20 03/23/21
MW-8 20 2 0-5 5-20 0-2 2-4 4-20 03/23/21
MW-9 20 2 0-5 5-20 0-3 3-4 4-20 09/28/21
MW-10 20 2 0-5 5-20 0-3 3-4 4-20 09/28/21
DW-1 54
5-Inch Outter Casing
to 23 Feet; 2-Inch 0-49 49-54 0-2 2-47 47-54 07/07/95
DW-2 77.5
5-Inch Outter Casing
to 23 Feet; 2-Inch
Inner Casing
0-72.5 72.5-77.5 0-2 2-70.5 70.5-72.5 10/09/95
TABLE 4
Monitoring Well Construction Details
Greensboro Children's Museum
Greensboro, North Carolina
5093 NC Highway 88 West
Table 5
Summary of Depth to Groundwater and Free Product Thickness
Greensboro Childrens Museum
Greensboro Childrens Museum
Greensboro, North Carolina
Depth Depth Free Free Corrected Corrected
Well Date TOC To To Product Product Depth To Water
Number Gauged Elevation Groundwater Product Thickness Adjustment Water Elevation
(feet) (feet) (feet) (feet) (feet) (feet) (feet)
4/9/2021 100.00 7.24 0.00 0.00 0.0000 7.24 92.76
9/30/2021 100.00 9.88 0.00 0.00 0.0000 9.88 90.12
8/29/2022 100.00 10.77 10.76 0.00 0.0000 10.77 89.23
10/4/2022 100.00 10.65 0.00 0.00 0.0000 10.65 89.35
4/9/2021 101.42 6.50 0.00 0.00 0.0000 6.50 94.92
9/30/2021 101.42 10.30 0.00 0.00 0.0000 10.30 91.12
8/29/2022 101.42 11.19 0.00 0.00 0.0000 11.19 90.23
10/4/2022 NS NS NS NS NS NS NS
4/9/2021 101.79 8.80 0.00* 0.00 0.0000 8.80 92.99
9/30/2021 101.79 11.86 0.00* 0.00 0.0000 11.86 89.93
8/29/2022 101.79 12.78 12.77 0.00 0.0000 12.78 89.01
10/4/2022 101.79 12.20 12.11 0.09 0.0675 12.13 89.66
4/9/2021 NS NS NS NS NS NS NS
9/30/2021 99.02 9.52 0.00 0.00 0.0000 9.52 89.50
8/29/2022 99.02 10.40 0.00 0.00 0.0000 10.40 88.62
10/4/2022 NS NS NS NS NS NS NS
4/9/2021 NS NS NS NS NS NS NS
9/30/2021 100.02 9.91 0.00 0.00 0.0000 9.91 90.11
8/29/2022 100.02 10.60 0.00 0.00 0.0000 10.60 89.42
10/4/2022 100.02 10.28 0.00 0.00 0.0000 10.28 89.74
NS = Not Sampled * = Sheen Observed
MW-1
MW-7
MW-8
MW-9
MW-10
N TS DATE MW-1 MW-7 MW-8 MW-9 MW-10 NCAC 2 GC sGroundwaterStandardAliphatic (C05-C08)ug/l 04-12-21NAP NAP9,980NININo StandardNo Standard09-30-21NAP NAP12,400NAPNAP10-04-22NAP NAP NAPNSNAPAliphatic (C09-C18)ug/l 04-12-21NAP NAP9700NININo StandardNo Standard09-30-21NAP NAP14,070NAPNAP10-04-22NAP NSNAPNSNAPAliphatic (C19-C36)ug/l 04-12-21NAP NAP6710NININo StandardNo Standard09-30-21NAP NAP527NAPNAP10-04-22NAP NSNAPNSNAPAromatic (C09-C22)ug/l 04-12-21NAP NAP2990NININo StandardNo Standard09-30-21NAP NAP8,010NAPNAP10-04-22NAP NSNAPNSNAPPA AMETEBenzeneug/l 04-12-21 6,330ND33.7NINI15,00009-30-21 7,610ND28.55.113610-04-22 5590NS51NS647Tolueneug/l 04-12-21 895ND948NINI600260,00009-30-21471 ND2,480ND36210-04-22 756NS6,800NS2,110Ethylbenzeneug/l 04-12-21 1310ND347NINI60084,50009-30-21 2,680ND1,260ND52.210-04-22 1,640NS1,940NS304Total Xylenesug/l 04-12-21 3050ND1,899NINI50085,50009-30-21 5,254ND5,950ND262.610-04-22 3,160NS9,930NS1,552TOTAL BTEXug/l04-12-2111585 ND 3,227.70 NININo StandardNo Standard09-30-2116,015 ND 5,718.50 5.1812.810-04-2211,146 NS 18,721NS4,613MTBEug/l 04-12-21 2,670ND15.2NINI2020,00009-30-21 2,010NDND1,470 1,54010-04-22 3,080NSNDNS303IPEug/l 04-12-21 426ND 26 NI NI70 70,00009-30-21 372ND ND138 43210-04-22 394NS ND NS 68.2Naphthaleneug/l 04-12-21 412ND129NI NI09-30-21 506ND337ND ND6.0 6,000.010-04-22 462NS668NS77.5Chloromethaneug/l 04-12-21 94.1ND ND NI NI(Methyl Chloride) 09-30-21ND ND34.3ND ND3.0 3,000.010-04-22ND NS ND NS NDug/l 04-12-21ND ND ND NI NI1,2-Dichloroethane09-30-21ND ND ND ND61.4 0.410-04-22ND NS ND NS NDtetrachloroetheneug/l 04-12-21ND ND ND NI NI0.7 7,000.009-30-21ND ND ND ND ND10-04-22ND NS ND NS NDtrichloroetheneug/l 04-12-21ND ND ND NI NI3.0 3,000.009-30-21ND ND ND ND ND10-04-22ND NS ND NS ND1,2,4-trimethylbenzeneug/l 04-12-21 615ND870NI NI400 28,50009-30-21 951ND2,070ND 6510-04-22 617NS1,970NS 3751,3,5-trimethylbenzeneug/l 04-12-21ND ND 240 NI NI400 25,00009-30-21259 ND ND ND 19.110-04-22170 NS443NS 103n-Butylbenzeneug/l 04-12-21ND ND ND NI NI09-30-21ND ND146ND 5.370 6,90010-04-22ND NS ND NS NDIsopropylbenzeneug/l 04-12-2147.5 ND 49 NI NI70 25,00009-30-21 96ND111ND ND10-04-2265.4 NS90.40NS12.9n-propylbenzeneug/l 04-12-21NDNDNDNINI7030,00009-30-21NDND335ND11.610-04-22153NS237NS30.5Styreneug/l 04-12-21NDND5.7NINI7070,00009-30-21NDNDNDNDND10-04-22NDNS 41.70NSND1,2-Dichloropropaneug/l 04-12-21NDNDNDNINI0.6600.009-30-21NDNDNDNDND10-04-22NDNSNDNSNDNAP=Not Analyzed for ParameterNS=Not SampledJ = Estimated Value NI = Not InstalledMADEP P6200TA E 6Groundwater Analytical esults October 2022 Greensboro Children s Museum - DE ncident 13231Page 1 of 1
NTSDATE MW-1 MW-2 MW-3 MW-4 MW-5 MW-6 DW-1 DW-2 MW-7 MW-8 NCAC 2 GC s Standard PA AMETEAliphatic (C05-C08)ug/l 08-06-98100,000 NS NS NS NS NS NS NSN N 07-19-0152,700 NS NS NS NS NS NS NSN N 10-24-0239,000 NS NS NS NS NS NS NSN N 05-09-03160,000 NS NS NS NS NS NS NSN N 05-25-0744,200 NS NS NS NS NS NS NSN N 02-09-1133,000Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21N ADestroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedN A 9,980Aliphatic (C09-C12)ug/l 08-06-987,600 NS NS NS NS NS NS NSN N 07-19-0120,700 NS NS NS NS NS NS NSN N 10-24-02BDLNS NS NSNS NS NSNSN N 05-09-0329,000 NS NS NS NS NS NS NSN N 05-25-073,310 NS NS NS NS NS NS NSN N 02-09-113,660Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21N ADestroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedN A 9,700Aromatic (C09-C10)ug/l 08-06-98250 NS NS NS NS NS NS NSN N 07-19-015,480 NS NS NS NS NS NS NSN N 10-24-02BDLNS NS NSNS NS NSNSN N 05-25-07BDLNS NS NSNS NS NSNSN N 05-09-03BDLNS NS NSNS NS NSNSN N 02-09-11967Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21N ADestroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedN A 2,990PA AMETE04-25-95 1,200N N N N N N N Not nstalled Not nstalled07-10-95NS1,700 380NDN N 830N N N Benzeneug/l 09-25-95NS1,300 3000ND ND FP NSN N N 15,00010-02-95 15,000NS NS NS NS NS480N N N 10-10-95NS NS NS NS NS NS NS8.6N N 03-13-98 11,500NS NS NS NS NS NS NSN N 06-26-98ND NS NS NS NS NS NS NSN N 08-06-98NAPNS NS NSNS NS NSNSN N 07-19-01 14,300NS NS NS NS NS NS NSN N 10-24-02 17,000NS NS NS NS NS NS NSN N 05-09-03 12,000NS NS NS NS NS NS NSN N 05-25-07 6,430NS NS NS NS NS NS NSN N 02-09-11 5,990Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20 10,300Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21 6330Destroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedBDL33.704-25-95 620N N N N N N N N N 07-10-95NS 1501,200NDN N 590N N N Tolueneug/l 09-25-95NS 3204,200ND ND FP NSN N N 600 260,00010-02-95 12000NS NS NS NS NS 230N N N 10-10-95NS NS NS NS NS NS NS NDN N 03-13-98 13,700NS NS NS NS NS NS NSN N 06-26-98BDLNS NS NSNS NS NSNSN N 08-06-98N ANS NS NSNS NS NSNSN N 07-19-01 2,850NS NS NS NS NS NS NSN N 10-24-02 9,000NS NS NS NS NS NS NSN N 05-09-03 8,000NS NS NS NS NS NS NSN N 05-25-07BDLNS NS NSNS NS NSNSN N 02-09-11175Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20 769Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21 895Destroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedBDL94804-25-95120N N N N N N N N N 07-10-95NS ND 170 NDN N 98N N N Ethylbenzeneug/l 09-25-95NS 520660ND ND FP NSN N N 60084,50010-02-95 1,000NS NS NS NS NS NDN N N 10-10-95NS NS NS NS NS NS NS NDN N 03-13-98BDLNS NS NSNS NS NSNSN N 06-26-98BDLNS NS NSNS NS NSNSN N 08-06-98N ANS NS NSNS NS NSNSN N 07-19-01BDLNS NS NSNS NS NSNSN N 10-24-02 14,000NS NS NS NS NS NS NSN N 05-09-03 860NS NS NS NS NS NS NSN N 05-25-07BDLNS NS NSNS NS NSNSN N 02-09-1188.5Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20 1,970Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21 1,310Destroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedBDL 347MADEP PEPA Method 6200TA E 7 istorical Groundwater Analytical esultsGreensboro Children s Museum - DE ncident 13231No Standard No StandardNo Standard No StandardNo Standard No StandardPage 1 of 3
TA E 7 istorical Groundwater Analytical esultsGreensboro Children s Museum - DE ncident 13231NTSDATE MW-1 MW-2 MW-3 MW-4 MW-5 MW-6 DW-1 DW-2 MW-7 MW-8 NCAC 2 GC s Standard 04-25-95 530N N N N N N N N N 07-10-95NS 390720NDN N 500N N N Total Xylenesug/l 09-25-95NS1,200 2,900ND ND FP NSN N N 50085,50010-02-95 4,000NS NS NS NS NS 230N N N 10-10-95NS NS NS NS NS NS NS NDN N 03-13-98 5,310NS NS NS NS NS NS NSN N 06-26-98BDLNS NS NSNS NS NSNSN N 08-06-98N ANS NS NSNS NS NSNSN N 07-19-01 1,330NS NS NS NS NS NS NSN N 10-24-02 3,600NS NS NS NS NS NS NSN N 05-09-03 3,600NS NS NS NS NS NS NSN N 05-25-07BDLNS NS NSNS NS NSNSN N 02-09-11454Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20 2,530Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21 3050Destroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedBDL1,89904-25-95 19,000N N N N N N N N N 07-10-95NS4,100 630NDN N 8,800N N N MTBEug/l 09-25-95NS2,000 6,000ND ND FP NSN N N 2020,00010-02-95 97,000NS NS NS NS NS8,700N N N 10-10-95NS NS NS NS NS NS NS160N N 03-13-98 42,600NS NS NS NS NS NS NSN N 06-26-98 425NS NS NS NS NS NS NSN N 08-06-98N ANS NS NSNS NS NSNSN N 07-19-01 31,500NS NS NS NS NS NS NSN N 10-24-02 16,000NS NS NS NS NS NS NSN N 05-09-03 20,000NS NS NS NS NS NS NSN N 05-25-07 20,000NS NS NS NS NS NS NSN N 02-09-11 12,050Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20 5,990Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21 2,670Destroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedBDL BDL04-25-95 NDN N N N N N N N N 07-10-95NS0.58 0.1NDN N NDN N N EDBug/l 09-25-95NS0.04 0.77ND ND FP NSN N N 0.025010-02-95 0.032NS NS NS NS NS NDN N N 10-10-95NS NS NS NS NS NS NS NDN N 03-13-98BDLNS NS NSNS NS NSNSN N 06-26-98N A NS NS NS NS NS NS NSN N 08-06-98N A NS NS NS NS NS NS NSN N 07-19-01N A NS NS NS NS NS NS NSN N 10-24-02N A NS NS NS NS NS NS NSN N 05-09-03N A NS NS NS NS NS NS NSN N 05-25-07N A NS NS NS NS NS NS NSN N 02-09-11BDLDestroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20BDLDestroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21BDLDestroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedBDL BDL04-25-95 1,700N N N N N N N N N 07-10-95NS ND ND NDN N NDN N N IPEug/l 09-25-95NS340 1,100ND ND FP NSN N N 7070,00010-02-95 6,900NS NS NS NS NS 590N N N 10-10-95NS NS NS NS NS NS NS 11N N 03-13-98 3,450NS NS NS NS NS NS NSN N 06-26-9815.7NS NS NSNS NS NSNSN N 08-06-98N ANS NS NSNS NS NSNSN N 07-19-01BDLNS NS NSNS NS NSNSN N 10-24-02 2,800NS NS NS NS NS NS NSN N 05-09-03 2,700NS NS NS NS NS NS NSN N 05-25-07 3,140NS NS NS NS NS NS NSN N 02-09-11 1,970Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20 720Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21 426Destroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedBDL 2604-25-95BDLN N N N N N N N N 07-10-95NS ND ND NDN N NDN N N Naphthaleneug/l 09-25-95NS ND ND ND ND FP NSN N N 66,00010-02-95BDL NS NS NS NS NS NDN N N 10-10-95NS NS NS NS NS NS NS NDN N 03-13-98BDLNS NS NSNS NS NSNSN N 06-26-98BDLNS NS NSNS NS NSNSN N 08-06-98N ANS NS NSNS NS NSNSN N 07-19-01BDLNS NS NSNS NS NSNSN N 10-24-02BDLNS NS NSNS NS NSNSN N 05-09-03BDLNS NS NSNS NS NSNSN N 05-25-07BDLNS NS NSNS NS NSNSN N 02-09-11 94.5Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20 472Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21 412Destroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedBDL129Page 2 of 3
TA E 7 istorical Groundwater Analytical esultsGreensboro Children s Museum - DE ncident 13231NTSDATE MW-1 MW-2 MW-3 MW-4 MW-5 MW-6 DW-1 DW-2 MW-7 MW-8 NCAC 2 GC s Standard 04-25-95BDLN N N N N N N N N 07-10-95NS ND ND NDN N NDN N N 1,2,4-trimethylbenzeneug/l 09-25-95NS ND ND ND ND FP NSN N N 40028,50010-02-95BDL NS NS NS NS NS NDN N N 10-10-95NS NS NS NS NS NS NS NDN N 03-13-98BDLNS NS NSNS NS NSNSN N 06-26-98BDLNS NS NSNS NS NSNSN N 08-06-98N ANS NS NSNS NS NSNSN N 07-19-01BDLNS NS NSNS NS NSNSN N 10-24-02BDLNS NS NSNS NS NSNSN N 05-09-03BDLNS NS NSNS NS NSNSN N 05-25-07BDLNS NS NSNS NS NSNSN N 02-09-11223Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20 540Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21 615Destroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedBDL87004-25-95BDLN N N N N N N N N 07-10-95NS ND ND NDN N NDN N N 1,3,5-trimethylbenzeneug/l 09-25-95NS ND ND ND ND FP NSN N N 40025,00010-02-95BDL NS NS NS NS NS NDN N N 10-10-95NS NS NS NS NS NS NS NDN N 03-13-98BDLNS NS NSNS NS NSNSN N 06-26-98BDLNS NS NSNS NS NSNSN N 08-06-98N ANS NS NSNS NS NSNSN N 07-19-01BDLNS NS NSNS NS NSNSN N 10-24-02BDLNS NS NSNS NS NSNSN N 05-09-03BDLNS NS NSNS NS NSNSN N 05-25-07BDLNS NS NSNS NS NSNSN N 02-09-1124.5 JDestroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20156Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21BDLDestroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedBDL 24004-25-95BDLN N N N N N N N N 07-10-95NS ND ND NDN N NDN N N Isopropylbenzeneug/l 09-25-95NS ND ND ND ND FP NSN N N 7025,00010-02-95BDL NS NS NS NS NS NDN N N 10-10-95NS NS NS NS NS NS NS NDN N 03-13-98BDLNS NS NSNS NS NSNSN N 06-26-98BDLNS NS NSNS NS NSNSN N 08-06-98N ANS NS NSNS NS NSNSN N 07-19-01BDLNS NS NSNS NS NSNSN N 10-24-02BDLNS NS NSNS NS NSNSN N 05-09-03BDLNS NS NSNS NS NSNSN N 05-25-07BDLNS NS NSNS NS NSNSN N 02-09-117.0 JDestroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20 73.8Destroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-2147.5Destroyed Destroyed Destroyed DestroyedNSDestroyed DestroyedBDL 4904-25-95 36N N N N N N N N N 07-10-95NS 9.5 7.3 5.9N N 5.3N N N Leadug/l 09-25-95NS ND ND ND ND NA NSN N N 1515,00010-02-956.5 NS NS NS NS NS 11N N N 10-10-95NS NS NS NS NS NS NS 12N N 03-13-983 NS NS NSNS NS NSNSN N 06-26-98N ANS NS NSNS NS NSNSN N 08-06-98N ANS NS NSNS NS NSNSN N 07-19-01N ANS NS NSNS NS NSNSN N 10-24-02N ANS NS NSNS NS NSNSN N 05-09-03N ANS NS NSNS NS NSNSN N 05-25-07N ANS NS NSNS NS NSNSN N 02-09-11N ADestroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 06-09-20N ADestroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N N 04-12-21N ADestroyed Destroyed Destroyed DestroyedNSDestroyed Destroyed N A N AN A = Not Analyzed for CompoundsJ = Estimated Value6,500 = Concentrations over GCLsNS = Not Sampledold alues are NCAC 2 Standards GCL = Gross Contaminant Levels BDL = Below Detection Limits. NI = Not InstalledEPA 6010 ( ead)Page 3 of 3
1 Oct. - Nov. 2022 96 hours MW-1, MW-8, & MW-10 5,403 10.50
5,403 10.50
TOTA
D OCA ONS
EMO ED AS
GASO NE APO S
(GA ONS)
MON TO NG WE S SED
FO E T ACT ON
E ENT
TOTA O ME EMO ED
TA E 8
MMPE Performance Results (October - November 2022)
Greensboro Children's Museum
220 N. Church Street, Greensboro, NC
DEQ Incident #13231
DATE OF MMPE
E ENT
DATON
GA ONS OF
G O NDWATE
EMO ED
Page 1 of 1















APPENDIXA

Site Name City / County /Guilford Incident #13231
Resp Pty Name / Contact /Incident Mgr Region WS
RP Type (Owner/Operator / Landowner / Attny-in-fact)Change Order?Prev. TA #2
Consultant / Project Mgr /Mike Jones
Telephone / Fax Number /Task Authorization Number:3 ChangeOrd:
Project Mgr Email Site Risk / Rank / Abatement:I-75-R RRA Date:2/5/2008
Proposal# / Scope Dates /% Commercial (C=100%, NC=0%, Both=1%-99%)
Has STF Eligibility Been Determined? (Y/N)Site Status (Active or NFA Date)
With Claim: [ ] All Main Consultant/Contractor invoices attached?[ ] Proof of payment attached directly to the front of each invoice?
ŠŠ Important: The date of reimbursement is dependent on the Trust Fund balance. There may be a delay in the reimbursement of claims for work under this ePATA.3rd Pty Ded?Task #Lab /
SubCode
RO AuthProposed
Rate/Price
(Consultant)CO AuthProposed Task
Subtotal
(Consultant)
Final
Preapproved
Subtotal
(UST Section)
Claimed
Amount3
(Consultant)
//
/
4.031 3 /wells 0 $110.00 N $330.00 $0.00 /
//
4.090 #272 3 / samples 0 $66.00 N $198.00 $0.00 /
//
7.420 96 / hours y $26.04 y $2,500.00 $2,500.00 /
7.420 1 / week y $2,325.00 y $2,325.00 $2,325.00 /
7.420 1 / equip y $1,500.00 y $1,500.00 $1,500.00 /
7.420 5000 / gallons y $0.350 y $1,750.00 $1,750.00 /
7.420 5000 / gallons y $0.250 y $1,250.00 $1,250.00 /
//
4.090 #880 3 / samples y $151.000 y $453.00 $453.00 /
4.091 1 / cost y $65.000 y $65.00 $65.00 /
//
7.201 6 / hours y $93.00 y $558.00 $558.00 /
//
12.050 2 / events y $250.00 y $500.00 $500.00 /
12.055 2 / events y $50.00 y $100.00 $100.00 /
//
/
4.031 3 /wells y $110.00 y $330.00 $330.00 /
12.050 1 / event y $250.00 y $250.00 $250.00 /
12.055 1 / event y $50.00 y $50.00 $50.00 /
//
4.090 #272 3 / samples y $66.00 y $198.00 $198.00 /
//
6.091 1 / report y $1,125.00 y $1,125.00 $1,125.00 /
//
//
//
//
//
//
Requested Preapproved Claimed3
TOTAL:$13,482.00 $12,954.00 TOTAL:
Total Standard Costs (Not Third Party)$13,482.00 $12,954.00 Total Standard Costs
Total applied as Third Party Deductible/Damage Costs $0.00 $0.00 Total Third Pty Costs
Process Tracking (Date)
TA Submittal: 6/6/22 by:(PM)(Reserved for RO)
RO Review: 6/10/22 by:(IM)Joint UST Preapproval Confirmed By:Date1 6/13/2022
CO Review: 6/13/22 by:(STF)RP or Designee Receipt Confirmed By:Date 4
1 - This ePATA expires one year from the Joint UST Preapproval date. This does not extend, alter, or supersede any regulatory deadlines (e.g., NORR's, NOV's, Enforcements, etc.)
2 - THE ONE YEAR STATUTE OF LIMITATIONS APPLIES TO EACH INDIVIDUAL TASK. Costs must be claimed within one year of completion of that task to be reimbursable.
3 - Only Tasks included on this ePATA may be claimed. Do not include other Tasks or claimed costs (i.e., Claim preparation) that were not preapproved or the claim will be returned.
4 - Preapproval is not valid (i.e., claimable) until receipt is signed as 'Confirmed' by the RP or their designee and returned to the Trust Fund within a week of approval. Signature
indicates acknowledgement of the tasks and amounts approved. Any objections/appeals must be submitted via Change Order prior to work proceeding. Scope/cost
negotiations do not supersede other regulatory deadlines as described in #1 above. Also, any ePATA that has been signed as 'Confirmed' by both the UST Section and RP
is not to be modified without written consent by all signatories.
5 - Tasks approved on Directed - CAB Only ePATAs must be performed in accordance with all applicable rules, statutes, and RRD Task Scopes of Work to be reimbursed in full.
DWM/UST ePATA 4/1/2022
Pyramid Environmental
[phone]
Proposed
Units / Type
(Consultant)
NO
Greensboro
Gene Mao
Greensboro Children's Museum
Gate City Motor Co.Bruce Beaton
June - July 2022
Dates of Work
(Consultant)
Started1 / Completed2
FINAL REIMBURSEMENT
100.00%
[phone]
[e-mail]
DIRECTED COSTS
(Must Complete with Claim Submittal)(See Instructions / RRD for Tasks requiring Preapproval / Task Authorization)
Owner/Operator
(Reserved for Incident Manager)
PREAPPROVAL / TASK AUTHORIZATION
Note This Electronic Preapproval Task Authori ation (ePATA) shall be used to receive preapproval from the ST Section. A proposal,including maps and figures,must be
attachedtoelaborate onthecosts forthetasks listedbelowthat describesthescope of workand the rationale for theproposed activities.f, following completion of this ePATA,
you discover that une pected tasks must be performed, incurring costs for tasks not originally included with this form, you must complete and submit a separate ePATA re uest
designated as a Change Order in the provided space above prior to conducting those tasks. nclude a copy of the prior ePATA form for confirmation. Please attach this form to
the cover of the corresponding claim when re uesting reimbursement. MPO TANT Only one claim may be submitted per ePATA and all work on the ePATA must have been
completed within12months of the completion date of theFSTcompleted task to remainwithin the Statute of imitations. All ePATAs submitted within a claim are closed with
that claim, and may not be re-used in a separate submittal, even for costs or tasks that were not originally claimed. Final reimbursement of costs associated with the Total
Claimed amount below may be affected by the eligibility status of the site (i.e., deductibles, apportionment, etc.), and the documentary validation of incurred costs as reasonable
and necessary e penses per 15A NCAC 2P .0402 and .0404.
LJM
TC
BDM
LJM
ActiveYES
7567
ELECTRONIC PREAPPROVAL TASK AUTHORIZATION FORM
Dept of Environmental Quality - Division of Waste Management
Brian D. Mahan 6/14/2022















APPENDIXB


APPENDIXCAPPENDIXC
StandardFieldProcedures:Revision10.6Page1
PyramidEnvironmental&Engineering,P.C.Revisiondate01Ͳ06Ͳ2020
Standard Field Procedures
Pyramid Environmental & Engineering, P.C.
________________________________________________________________________
1.0 Equipment Decontamination
Equipmentdecontaminationisessentialtoassurerepresentativeenvironmentalsamples
arecollectedandtoeliminatethepotentialforcrossͲcontaminationbetweensamplepoints.
Pyramidstrivestocleanallfieldequipmentpriortoleavingtheoffice;however,field
decontaminationisstillrequiredonmostprojects.Theproceduresfordecontaminationof
waterlevelprobes,handaugers,samplingprobes,trowels,andotherfieldequipmentare
listedbelow.

1.1 EPA Region IV Decontamination Procedures 
Drillingandsoilsamplingequipmentisdecontaminatedpriortoeachuseusingapressure
washerorsteamcleaner.Reusablesamplingequipment(handaugers,samplingprobes,
trowels,splitspoonsamplers,watersamplingequipment,etc.…)aredecontaminatedusing
thegeneralproceduredescribedbelow.x WashwithnonͲphosphatedetergent,water,&brushtoremoveparticulatematter
x Rinsewithtapwater
x Rinsewith10percentnitricacidsolution(onlyifsamplingformetals)
x RinsewithdeͲionizedwater
x RinsewithpesticideͲgradeisopropylalcohol
x RinsewithdeͲionizedwater
x AirͲdryaslongaspossible
Thelevelofdecontaminationusedisappropriatetotheanalyticalparametersselectedand
thematerialofthesamplingdevicebeingusedforsampling.Forexample,ifmetalsanalyses
arerequired,thenthe10%nitricacidsolutionisusedfordecontaminationofstainlessͲsteel
equipment.PyramidusesdeͲionizedordistilledwaterfordecontamination.Equipmentthat
isnotusedimmediatelyafterdecontaminationiswrappedinaluminumfoilpriortostorage.

2.0 Soil Borings & Sampling
2.1 Soil Borings 
SoilboringsareusedbyPyramidtoinvestigateandcharacterizethesubsurfaceatsites.
Soilboringsprovideinformationconcerningsoiltypesanddensity,depthtorefusal,depth
tobedrock,organicvaporsthatmaybepresent,andcanbeusedtoobtainsamplesfor
laboratoryanalysis.
StandardFieldProcedures:Revision10.6Page2
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Pyramidconductsboringsinseveraldifferentways,usinghandaugers,directͲpush
equipment(Geoprobe),sampleprobes,splitͲspoonsamplers(ASTMD1586Ͳ84),auger
drilling,airdrilling,andVibroͲCore.ThefollowingproceduresareusedbyPyramid
Environmentalwhenperformingsoilborings:
1. Soilboringlocationsarechosen,andtheULOCOutilitylocatingserviceiscalledto
markallpublicutilities.Pyramidlocatesprivateutilitiesatmanyprojectsitesusing
Pyramidlocatingequipment,orusesaprivateutilitylocatingservice.

2. Downholedrillingequipmentiscleanedpriortouseandbetweenboringsusing
pressurewashingorsteamcleaning.Additionaldecontaminationproceduresin
Section1.1areusedforsamplingtoolssuchassplitspoonsordirectͲpushpoints.

3. SoilboringsareadvancedusingdirectͲpush,drillingrigs,handaugers,orother
appropriatemeans.NearͲsurfacesoilsamplesmayalsobecollectedusingstainless
steelpushprobes,shovels,scoops,orothersamplingdevices.

4. Soilsamplesarenormallycollectedataminimumof5Ͳfootintervals.Eachsampleis
dividedintotwoparts.Soilsamplesforlaboratoryanalysesarejarredfromtheinitial
samplevolume.Theremainingsoilisstoredinasealedcontainerforheadspace
analysisandgeologicaldescription.

5. Afterscreeningthesoilwiththefieldinstruments,eachsoilsampleisdescribedby
thefieldgeologistandageologicdescriptionisrecordedinprojectdocumentation.

6. Soilsaretypicallydescribedinthefieldbytheprojectgeologistorsoilscientistand
areclassifiedaccordingtotheUnifiedSoilClassificationSystem(ASTMD2488Ͳ84).

7. Soilsamplesselectedforlaboratoryanalysisareplacedinproperlyprepared,
laboratorysuppliedcontainersandimmediatelypackedinacooleronice.Sample
custodyismaintainedusingstandardchainͲofͲcustody(COC)proceduresthrough
deliverytotheanalyticallaboratory.

8. Soilborings,whicharenotcompletedasmonitoringwells,aregroutedusinga
Portlandcement,bentonite,orbackfilledwithsoilcuttings.

9. Soilcuttingsaregenerallyspreadnearthesoilboringormonitoringwelllocationas
directedbyStateregulatorymanagers.Drillcuttingsaredrummed(containerized)
wheresiteconditionsorregulatoryrequirementsprohibitspreadingcuttings,and
aredisposedoffͲsite(afterwastedeterminationismade).



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2.2 Soil Headspace Screening 
Soilsamplesareroutinelyscreenedforvolatileorganiccompounds(VOCs)whichmaybean
indicationoforganicorpetroleumhydrocarboncontamination.Thetypicalscreening
procedureincludesimmediatelytransferringthesoilfromthesamplingdevicestoasealed
container(sealed1ͲgallonZiplockplasticbag).Thesoilcontainerisfilledapproximately
halfwaywithsoilandsealed.ThiscreatesheadspaceabovethesoilinwhichVOCsmay
accumulate.Thecontainerisallowedtostandfor5to15minutesfortheVOCstoequilibrate
intheheadspaceofthecontainer.Theheadspaceofthecontaineristhenscreenedusinga
calibratedorganicvaporanalyzer(PIDorFID).Thescreeningisconductedbycrackingthe
sealonlyenoughtoallowinsertionoftheprobeintotheheadspacesoasnottodilutethe
sample.Inmostcaseswherethecontaminantofconcernincludesvolatileorganics,the
highestor“Peak“fieldͲscreeningresultisdocumentedforeachsample.Thesoilsamples
showingthehighestreadingfromeachboringaretypicallyselectedforlaboratoryanalysis.

2.3 Soil Sample Collection for Laboratory Analysis 
Afterthetargeteddepthhasbeenreached,soilsamplesarecollectedusingavarietyof
samplingdevices.SoilsampledevicesusedincludesplitͲspoons,stainlessͲsteelhandaugers,
stainlessͲsteelpushͲprobesandsamplingscoops,anddirectlyfromthecenterofthe
excavatorbucket.Thesampletechnicianusesdisposablenitrilegloves,whicharechanged
betweensamplestoavoidcrossͲcontaminationofsamples,andeachsamplingdeviceis
decontaminatedpriortouse.

Onlylaboratoryprovidedcontainersareusedforsamplecollection.Samplesarecollected
inaccordancewiththepreservationmethodsrequiredbytherequestedanalyticalmethod.
Samplesarehandledaslittleaspossibleandpreservedinthefieldasspecifiedforthe
analyticalmethod.Thesamplesarestoredandtransportedtothelaboratoryinaninsulated
coolerchilledtoapproximately4degreescentigrade.Thesamplesarelabeledwitha
minimumofthefollowinginformation:Pyramid,projectnameornumber,sample
identification,datecollected,samplername,andanalysisrequested.Samplecustodyis
maintainedusingstandardchainͲofͲcustodyproceduresthroughdeliverytotheanalytical
laboratory.Notesofthesamplingeventsarerecordedinprojectdocumentation.
Incrementalsamplingmethodology(ISM)isastructuredcompositesamplingand
processingprotocolthatreducesdatavariabilityandprovidesareasonablyunbiased
estimateofmeancontaminantconcentrationsinavolumeofsoiltargetedforsampling.
ISMprovidesrepresentativesamplesofspecificsoilvolumesdefinedasdecisionunits
(DUs)bycollectingnumerousincrementsofsoil(typically30–100increments)thatare
combined,processed,andsubsampledaccordingtospecificprotocols.ISMSamplingwill
befurtherexplainedinasiteͲspecificWorkPlandocuments.
PyramidwillcontractanonͲsitelaboratoryforimmediateanalysesasneeded.
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2.4 Sediment Sample Collection for Laboratory Analysis 
Nearsurfacesedimentmaybepresentinasurfacewaterditch,stream,ordryintermittent
streambed.Sedimentsamplesaretypicallysoilrelatedsamplesandmaybecollectedwith
avarietyofsamplingtools.PyramidwillusestainlessͲsteelsamplerswhichhavebeen
decontaminatedaccordingtotheproceduredetailedinsection1.1ofthisdocument.After
thesedimentsamplesarecollected,thelocation,depth,conditions,andsample
compositionaredocumentedintheprojectrecords.Thesampleswillbescreenedinthe
fieldtodetectvolatileorganicvaporsandvisuallyexaminedforcontamination.Sediment
sampleswillbepreservedinlaboratorypreparedcontainersinaccordancewithsample
preservationrecommendationoftheanalyticallaboratory.Samplesarehandledaslittleas
possibleandpreservedinthefieldasspecifiedfortheanalyticalmethod.Thesamplesare
storedandtransportedinaninsulatedcoolerchilledtoapproximately4degreescentigrade.
Thesamplesarelabeledwithaminimumofthefollowinginformation:Pyramid,project
nameornumber,sampleidentification,datecollected,samplername,andanalysis
requested.SamplecustodyismaintainedusingstandardchainͲofͲcustodyprocedures
throughdeliverytotheanalyticallaboratory.Documentationofthesamplingeventsare
recordedintheprojectdocumentation.

3.0 Direct-Push Sampling Procedures

DirectͲpushsamplingtechniqueshavebeenusedatmanysitestocollectsoiland
groundwatersamplesrapidlyandinexpensively.TrackͲmounted,directͲpushrigscanaccess
hardtoreachareasandallowboringsandmonitoringwellstobeinstalled.Forsoilsampling,
typically,thedirectͲpushsteeldrivetubeisdecontaminatedusingapressurewasher,anda
newplasticsamplelinerisinsertedinthesteeldrivetubetocollectsoilsamples.Thesoil
samplesarecollectedinnewpolyethylenesampletubeswithinthesteeldrivetube.Thesoil
samplesarethenextractedfromthepolyethylenelinerandpreservedasrequiredfor
laboratoryanalysis.

Forgroundwatersampling,asteelprobewitharetractablescreensectionandtubingare
driventodepthandthescreenedsectionisopenedtoallowgroundwatertoenterthe
tubing.ThewatersamplesarewithdrawnusingnewpolyethyleneandTeflon®tubingwith
eitheradecontaminatedstainlessͲsteelcheckball,orperistalticpump.Thegroundwater
sampleisplaceddirectlyintotheappropriatelaboratorycontainersandsealedimmediately.
TopreventcrossͲcontaminationofsamples,newdisposabletubingisusedforeach
groundwatersamplepoint.Disposablenitrileglovesarewornbyfieldpersonnelduring
developmentandgroundwatersampling,andglovesarechangedbetweensamples.
GroundwatersamplingproceduresaredetailedmoreinSection5.0,asappropriateforeach
analyticalmethod.


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4.0 Monitoring Well Installation

Groundwatermonitoringwellsareinstalledinmanysubsurfaceenvironments;Coastal
Plain,sedimentary,Piedmontsaprolite,weatheredrockformations,andmountainterrains
tolistafew.Formationsencounteredincludeunconsolidatedandconsolidatedsediments,
fillmaterial,organicsoils,saproliticsoils,weatheredrockformations,andbedrock.
Groundwatermonitoringwellsprovideastablesamplingpointatdiscreteintervalswithin
theconfinedorunconfinedaquifers.Monitoringwellsareinstalledforanumberofreasons,
andaretypicallyinstalledas1Ͳinch,2Ͳinch,4Ͳinch,or6Ͳinchdiameterwells.Construction
maybeofPVC,stainlessͲsteel,HDPE,orotherappropriatematerials.Thefollowing
proceduresareusedbyPyramidwhenperformingboringsandmonitoringwellinstallations.x Ifrequired,monitoringwellpermitsareobtainedfromtheState,County,orCity.
x Boringandmonitoringwelllocationsarechosen,andutilitiesaremarkedbythe
publicutilitylocatingcompany.Asneeded,thelocationsmaybescannedforutilities
byPyramidusingourlocatingequipment,oraprivateutilitylocatingcompany.
x Inselectingadrillsite,careistakentoavoidoverheadpowerlines,andsubsurface
utilitieswheneverpossible.
x DownͲholedrillingequipmentisdecontaminatedpriortouseandbetweenborings.
x BoringsareadvancedusingdirectͲpush,drillingrigs,handaugers,solidͲstemaugers,
hollowͲstemaugers,airrotarydrilling,orairhammerdrilling.
x Soilsamplesarenormallycollectedataminimumof5Ͳfootintervals.Eachsampleis
dividedintotwoparts.Soilsamplesforlaboratoryanalysesarejarredfromtheinitial
samplevolume.Theremainingsoilisstoredinasealedcontainerforheadspace
analysiswithanorganicvaporanalyzer(PIDorFID).
x Afterscreeningthesoilwiththefieldinstruments,eachsoilsampleisdescribedby
thefieldgeologistandageologicdescriptionisrecordedintheproject
documentation.

TypeIImonitoringwellsareusuallyinstalledusing2Ͳinchdiameterschedule40PVCriser
and2Ͳinch,0.010Ͳinchmachineslottedwellscreen.Thescreenedintervallengthvarieswith
thegeologicsiteconditions,expectedvariationsinwaterlevel,andtheinvestigationgoals
forthewell.Thewellconstructiondetailsarepresentedontheboringlog.

TypeIIIwellsareusuallyinstalledasdoubleͲcasedwellstomonitorthedeeperportionsof
theaquifer.Thefirstcasingisusuallya5to6ͲinchdiametersolidPVCwellcasingdrilledto
bedrockoranappropriatedepthwithinthesurficialzone.The5to6Ͳinchdiametercasing
isthensetandgroutedintheborehole.Afterthecementgrouthassetfor12to24Ͳhours,
theboreholeiscompletedtothedesireddepthusingairrotarydrillingorairhammer
drilling.TheinsidecasingoftheTypeIIImonitoringwellisusuallyconstructedof2Ͳinch
diameterSCH40PVCcasingand2ͲinchdiameterSCH40PVC0.010Ͳinchslottedwellscreen.

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Inmostapplications,asandfilterpackof#2wellsand(orappropriatelysizedwellsand).
Sandistypicallyinstalledtoalevelof2feetabovethetopofthescreenineachwell.
Aminimum2Ͳfootthickbentonitesealisusuallyplacedontopofthefilterpackand
hydratedwithdeͲionizedordistilledwater.Theremainingannularspaceofatypicalwellis
backfilledtogradewithaPortlandcement/bentonitegrout.Inmonitoringwellswherethe
watertableisclosetosurface,theamountofsandabovethescreenandbentonitewillbe
reducedtoallowforaminimumof2–3feetofcementgroutinthewellbore.

Atthesurface,eachwellissecuredwithalockingcapandasteelwellprotector.Depending
onthesurfaceconditions,thewellmaybeprotectedbyaflushͲmountedmanholesetinthe
surroundingsurfaceinaconcretepad.Insomecases,stickͲupwellprotectorsareusedto
securethewellandallowthewelltobemoreeasilylocatedinwoodedoropenareas.

Eachgroundwatermonitoringwellisdevelopedbysurging,pumping,orbailingtoremove
sedimentbeforesampling.Waterremovedduringdevelopmentismanagedaccordingto
individualStateregulatoryguidance.


5.0 Water Sampling Procedures

Pyramidreliesonwatersamplingasaprimarymethodforassessmentofsubsurface
groundwaterconditions.Watersamplingtypicallyincludessamplinggroundwaterfrom
monitoringwells,watersupplywells,surfacewaterbodies,stormwater,wastesumps,etc.
Thefollowingprovidestypicalsamplingproceduresforthewatersamples.

5.1 Monitoring Wells 
Priortosamplingeachmonitoringwell,depthtoliquidand/orliquidsandtotalwelldepth
aremeasuredusingaproperlydecontaminatedelectricinterfaceprobe.IfphaseͲseparated
petroleumproductisdetectedinawell,theproductmeasurementsarerecordedalongwith
thewaterlevelineachwell.Thisinformationisrecordedinthefieldrecordandthevolume
ofthewaterinthewellcasingiscalculated.Topurgestagnantwaterfromeachmonitoring
well,threetofivewellcasingvolumesofwaterareremovedfromeachwellpriorto
sampling.Alternately,forlowͲflowsampling,developmentcontinuesuntilthefield
parameters(pH,conductivity,dissolvedoxygen,ORP,andtemperature)havestabilized.
Ifthewaterinthemonitoringwellisremoveduntilthewellisdry,thenthewellissampled
thereafter.Waterremovedfromwellsduringpurgingismanagedinaccordancewith
individualStateregulatoryguidance.

Groundwatersamplesaretypicallycollectedusinganewdisposablepolyethylenebailerand
anewlengthofnyloncord.TopreventcrossͲcontaminationofsamplesbetweenwells,a
newdisposablebailerisusedforeachwell.Thebailerisloweredintothegroundwater
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slowlyandremovedslowly.Anewpairofdisposableglovesiswornbyfieldpersonnel
duringpurgingandsampling,andischangedbetweenwells.Inthecaseofsmalldiameter
monitoringwellsordirectͲpushwatersamples,watersamplesmaybecollectedusinga
peristalticpumpandnewpolyethylenetubing.Anothermethodistouseasegmentofnew
samplingtubingandastainlessͲsteelcheckballtocreatea“TubeBailer”.
Groundwatersamplesselectedforlaboratoryanalysisareimmediatelyplacedinproperly
prepared,laboratorysuppliedcontainersandpreservedinacooleronice.Samplesare
maintainedunderstandardchainͲofͲcustodyproceduresfromsamplecollectionthrough
laboratoryanalysis.

5.2 Water Supply Well Sampling 
Priortosamplingeachwatersupplywell,thewellowneriscontactedtoprovideaccessto
thewell.Thewellownerisinterviewedtolocatethefaucetclosesttothewellforsampling.
Iftherearenofaucetslocatedonthewell,thenwaterfromanoutsidefaucetatthebuilding
isusuallysampled.Iftherearenooutsidefaucetsavailable,thenthewatersamplesare
collectedfromaninsidefaucet.Thelocationofthesampleisrecordedinthefieldrecord.
Theownerisinterviewedtoseeifthereisachlorinationsystemonthewell,orifthewell
hasbeenrecentlychlorinated.Recentchlorinationcouldaffectthelaboratorydetection
limits.Inmostcases,thesamplesarepreservedusingsodiumthiosulfateorascorbicacidto
removetheinteractionsofchlorine,whichmaybepresentinthesamples.
IfthewellistreatedwithaPointͲofͲEntry(POE)treatmentsystem,thenthe“raw”water
samplemustbecollectedbeforethetreatmentsystem.Anassociatedtreatedwatersample
isusuallycollectedaswelltodemonstrateeffectivetreatment.
Topurgestagnantwaterfromthewatersupplywellsystem,thefaucetisallowedtorunon
fullstreamforaminimumof15minutes.Theaeratorisremovedfromthetapifoneis
present.Waterremovedfromwellsduringpurgingismanagedaccordingtoregulatory
standards.
Watersupplywellsamplesarecollectedusingappropriatelaboratorypreparedcontainers
foreachanalysis.Theanalyticalmethodsselectedwillvarywiththecontaminantof
interest.TopreventcrossͲcontaminationofsamplesbetweenwells,disposablenitrilegloves
arewornbyfieldpersonnelduringpurgingandsamplingandarechangedbetweenwells.It
ispossiblethatsamplesmayberequiredatseveralplaceswithinthewatersupplysystem.
Thesamplesarecollectedaccordinglyandlabeledtoshowthesourceandlocationsampled.
Supplywellsamplesselectedforlaboratoryanalysisareimmediatelyplacedinproperly
prepared,laboratorysuppliedcontainersandpackedinacooleronice,andchilledto
approximately4degreesCelsius.SamplesaremaintainedunderstandardchainͲofͲcustody
proceduresfromsamplecollectionthroughlaboratoryanalysis.

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5.3 Surface Water Sampling 
Surfacewatersamplesareobtainedusingseveraltechniquesincludinguseofsample
bailers,discretedepthintervalsamples,samplescoops,fromboats,bridges,orwadinginto
astream.Cautionshouldalwaysbeusedwhensamplingsurfacewatertoensurethatthe
watercollectedisrepresentativeofthesiteconditions.Sincestreamoropenwatersampling
istransient,carefuldocumentationofthesiteconditions,weather,surfaceconditions,
sediment,algalorbiologicalmaterial,etc.isrequired.

Inmanystudies,additionalsamplesfromupstreamanddownstreamofthedesiredsample
pointarerequired.SurfacewatersamplingmustbeplannedtoreflectthesiteͲspecific
conditionsduringsampling.Thegeneralproceduresaresimilartothesupplywellsampling
proceduresdetailedabove.Appropriatelaboratorypreparedcontainersareusedforeach
analysis.Theanalyticalmethodsselectedwillvarywiththecontaminantofinterest.

TopreventcrossͲcontaminationofsamplesbetweensamples,disposablenitrileglovesare
wornbyfieldpersonnelduringpurgingandsamplingandarechangedbetweensamples.It
ispossiblethatsamplesmayberequiredatseveralplacesalongthestreamtocheckfor
influencesofupͲstreamfacilities.Sampleswillbecollectedaccordinglyandlabeledtoshow
thesourceandlocationsampled.Samplewillalwaysbecollectedupstreamofthearea
disturbedbythepersonsamplingthestream.Surfacewatersamplesselectedforlaboratory
analysisareplacedinproperlyprepared,laboratorysuppliedcontainersandimmediately
packedinacooleronice.SamplesaremaintainedunderstrictcontrolusingstandardchainͲ
ofͲcustodyproceduresthroughlaboratoryanalysis.

6.0 Quality Assurance / Quality Control

Thefieldandlaboratoryprocedureslistedabovehavebeenimplementedonmanysites
withexcellentresults.Theproceduresareoftenverifiedbyanappropriateuseofthe
followingenvironmentalsamples.

TripBlanks(orTravelblanks)
TheTripBlank(ortravelblanks)areoftenusedtoverifythattheenvironmentalsamplesare
notimpactedduringshipping,andverifythatthesourceoftheglasswareisnotthesource
ofcontamination.ThetripblanksarepreserveddeͲionizedwater,collectedinthe
laboratory,andshippedwiththesamplecontainerstoPyramidorthesite.Thetripblank
remainsinthesamplecoolerandisshippedbacktothelaboratorywiththeenvironmental
samples.Thetripblankismostcommonlyanalyzedforvolatileorganiccompounds(VOCs),
andcorrespondtothetargetanalyses.



StandardFieldProcedures:Revision10.6Page9
PyramidEnvironmental&Engineering,P.C.Revisiondate01Ͳ06Ͳ2020
FieldBlanks
FieldBlanksarequalityassurancesampleswhicharecollectedinthefieldtorepresentthe
conditionspresentatthetimethesamplesarecollected.Forwatersamples,thelaboratory
containersareopenedandfilledinthefieldusingdeͲionized(ordistilled)waterfroma
knownsource.Thesamplesreflectanysiteconditionssuchasvaporsourceswhichmay
affectthewatersamples.Thesamplesthentraveltothelaboratorywiththeothersamples
foranalysis.Comparisonofthefieldblankresultswiththesampleresultsmayindicatea
pervasivesiteconstituentdetectedinthesamples.

EquipmentBlanks
EquipmentBlanksareusedtoverifywhetherthedecontaminationproceduresusedforthe
sampleequipment(orthenewequipment)mayhaveaddedanycontaminantstothe
sampleduringcollection.IfanonͲdisposablesamplingdeviceisused(suchasasampling
treir,scoop,handauger,Teflonbailer,etc.…),thenthedecontaminationofthesampling
deviceisusuallyverifiedusinganequipmentblank.Theequipmentblankiscollectedusing
deͲionized(ordistilled)waterfromaknownsource.Theequipmentisdecontaminated,
allowedtoairdry,thewaterispouredover(orthrough)theequipment,andasampleis
collectedintheappropriatesamplecontainers.Theequipmentblanksamplesarepreserved
withtheotherenvironmentalsamples,andshippedforanalysesforthetargetparameters.

DuplicateSamples
DuplicateSamplesareusedtoverifythesamplingproceduresandevaluatelaboratory
analysisvariability.Theduplicatesamplesmaybecollectedfromsoil,sediment,air,surface
water,wastes,orgroundwater.Thesesamplesarecollectedandsenttothelaboratoryas
blindsamplestohavemaximumeffectiveness.Duplicatesamplesaregenerallyanalyzedfor
thesameanalyticalmethodsastheactualenvironmentalsamplefordirectcomparison.
Duplicatesamplesmayalsobesplitbetweentwodifferentlaboratoriestoprovide
verificationoflaboratorydetectionlimitsorqualityprocessverification.

BackgroundSamples
BackgroundSamplesareatoolforcomparisonofgeneralsiteconditionswithsourcearea
siteconditions.Backgroundsamplesmaybesoil,sediment,air,surfacewater,waste,or
groundwater.Thegoalistoreflectconditionsoutsidetheexpectedareaofcontamination.
Thesesamplesarecollectedoutsidetheexpectedareaofcontaminationandsenttothe
laboratoryforanalyses.Backgroundsamplesaregenerallyanalyzedforthesameanalytical
methodsasthesourceareaenvironmentalsamplesfordirectcomparison.Background
samplesformetalscomparisonarecommontypesofbackgroundsamplesusedin
environmentalinvestigations.


















APPENDIXD


ydrocarbon Analysis esultsClientPyramid Samples takenTuesday, September 28, 2021AddressGreensboro, NCSamples e tractedTuesday, September 28, 2021Samples analysedFriday, October 1, 2021ContactBrian MahanOperatorTori Kelly Project#2021-22933U04049MatriSample DDilution usedTE (C6 - C9)G O (C5 - C10)D O (C10 - C35)TP (C5 - C35)Total Aromatics (C10-C35)16 EPA PA saP C Fingerprint Match light midheavys MW-9 5'20.6 <0.52 29.6 190.4 220 59.5 2.1 <0.021 90 9.1 0.9Deg.Diesel 81.8%,(FCM)s MW-10 7.5-10'21.8 20.6 91.7 96.3 188 4.7 0.51 <0.022 97.7 2 0.3Waste Oil 81.9%,(FCM),(BO)InitialCalibratorQCcheckOKFinalFCMQCCheckOK103.8 %Results generated by a QED HC-1 analyser. Concentration values in mg/kg for soil samples and mg/L for water samples. Soil values are not corrected for moisture or stone contentFingerprints provide a tentative hydrocarbon identification. The abbreviations are:- FCM = Results calculated using Fundamental Calibration Mode : % = confidence for sample fingerprint match to library(SBS) or (LBS) = Site Specific or Library Background Subtraction applied to result : (PFM) = Poor Fingerprint Match : (T) = Turbid : (P) = Particulate presentatios
QEDHydrocarbonFingerprints
Project: #2021Ͳ229 ##################














APPENDIXE


Pyramid Environmental & Engineering, P.C.
FIELD DRILLING RECORD
PROJECT NAME:
PROJECT NUMBER:
BORING/WELL NO:
SITE LOCATION: BORING/WELL
LOCATION:
START DATE: COMPLETED:
GEOLOGIST:DRILLER:
DRILL METHOD: SAMPLE METHOD:
BORING DIA: CASING DIA:
TOTAL DEPTH: CASING DEPTH:
DEPTH
(ft.)
VISUAL MANUAL SOIL CLASSIFICATION
COLOR, TEXTURE, STRUCTURE, CONSISTENCY, ODOR, ETC.
OVA RESULTS
PERCENT RECOVERY
BLOW COUNTS
MONITORING WELL INFORMATION (IF APPLICABLE)
RISER LENGTH (ft) DEPTH (ft) DIAMETER (in) MATERIAL .
SCREEN LENGTH (ft) DEPTH (ft) DIAMETER (in) MATERIAL .
DEPTH TO TOP OF SAND BAGS OF SAND .
DEPTH TO TOP SEAL BENTONITE USED BAGS OF CEMENT USED .
Greensboro Childrens Museum 9
220 N. Church St.Storm water drainage ditch
09/28 09/28
Brian Mahan 3D
Geoprobe Grab
6"N/A
20 N/A
Brown Sandy clayey silt (ML), moist, no petroleum odor
5 PVC
20 PVC
4
0.5 0.5
Orange & gray sandy clayey silt (ML), moist, strong odor
Light gray sandy clayey silt (ML), moist, light odor
Light brown sandy clayey silt (ML), very moist, light odor
Light brown sandy clayey silt (ML), very moist, moderate odor
Light gray sandy clayey silt (ML), moist, moderate odor
Orange sandy clayey silt (ML), very moist, light odor
Light brown sandy clayey silt (ML), moist, light odor20
17.5
15
12.5
10
8
5
0-1.5 0ppm
345 ppm
115 ppm
140 ppm
55.4 ppm
53 ppm
27.5 ppm
60 ppm
5
15
2
2
2
0.5
Pyramid Environmental & Engineering, P.C.
FIELD DRILLING RECORD
PROJECT NAME:
PROJECT NUMBER:
BORING/WELL NO:
SITE LOCATION: BORING/WELL
LOCATION:
START DATE: COMPLETED:
GEOLOGIST:DRILLER:
DRILL METHOD: SAMPLE METHOD:
BORING DIA: CASING DIA:
TOTAL DEPTH: CASING DEPTH:
DEPTH
(ft.)
VISUAL MANUAL SOIL CLASSIFICATION
COLOR, TEXTURE, STRUCTURE, CONSISTENCY, ODOR, ETC.
OVA RESULTS
PERCENT RECOVERY
BLOW COUNTS
MONITORING WELL INFORMATION (IF APPLICABLE)
RISER LENGTH (ft) DEPTH (ft) DIAMETER (in) MATERIAL .
SCREEN LENGTH (ft) DEPTH (ft) DIAMETER (in) MATERIAL .
DEPTH TO TOP OF SAND BAGS OF SAND .
DEPTH TO TOP SEAL BENTONITE USED BAGS OF CEMENT USED .
Greensboro Childrens Museum 10
220 N. Church St.Parking lot
09/28 09/28
Brian Mahan 3D
Geoprobe Grab
6"N/A
20 N/A
Red sandy clayey silt (ML), moist, faint odor
5 PVC
20 PVC
4
0.5 0.5
Light gray sandy clayey silt (ML), moist, faint odor
Light gray sandy clayey silt (ML), moist, moderate odor
Light gray sandy clayey silt (ML), moist, strong odor
Light gray sandy clayey silt (ML), moist, strong odor
Orange to light gray sandy clayey silt (ML), moist, strong odor
Light orange sandy clayey silt (ML), very moist, moderate odor
Light orange sandy clayey silt (ML), very moist, strong odor (geoprobe
picked up soil from contaminated layer)
Light orange sandy clayey silt (ML), wet, faint odor17.5-20
15-17.5
12.5-15
11-12.5
10-11
7.5-10
5-7.5
2.5-5
0-2.5 56 ppm
32 ppm
52.1 ppm
75,000 ppm
75,000 ppm
75,000 ppm
346 ppm
75,000 ppm
207 ppm
5
15
2
2
2
0.5
Pyramid Environmental & Engineering, P.C.
FIELD DRILLING RECORD
PROJECT NAME:
PROJECT NUMBER:
BORING/WELL NO:
SITE LOCATION: BORING/WELL
LOCATION:
START DATE: COMPLETED:
GEOLOGIST:DRILLER:
DRILL METHOD: SAMPLE METHOD:
BORING DIA: CASING DIA:
TOTAL DEPTH: CASING DEPTH:
DEPTH
(ft.)
VISUAL MANUAL SOIL CLASSIFICATION
COLOR, TEXTURE, STRUCTURE, CONSISTENCY, ODOR, ETC.
OVA RESULTS
PERCENT RECOVERY
BLOW COUNTS
MONITORING WELL INFORMATION (IF APPLICABLE)
RISER LENGTH (ft) DEPTH (ft) DIAMETER (in) MATERIAL .
SCREEN LENGTH (ft) DEPTH (ft) DIAMETER (in) MATERIAL .
DEPTH TO TOP OF SAND BAGS OF SAND .
DEPTH TO TOP SEAL BENTONITE USED BAGS OF CEMENT USED .
Greensboro Children's Museum MW-7
220 N. Church Street,
Greensboro, NC
Parking lot
3/23/2021 3/23/2021
Brian Mahan 3D
Rotary Auger Grab
4'NA
20'N/A
0-5'PVC
5-20'PVC
5
2.5
Orange and brown sandy clayey silt (ML) , dry, light petroleum odor
Light gray sandy clayey silt (ML), moist, no petroleum odor
Light gray sandy clayey silt (ML), moist, no petroleum odor
Light gray sandy clayey silt (ML), moist, no petroleum odor
Gray sandy clayey silt (ML), moist, no petroleum odor
Light brown sandy clayey silt (ML), moist, no petroleum odor
Light brown sandy clayey silt (ML), moist, no petroleum odor
Brown to orange sandy clayey silt (ML), moist, no petroleum odor
End of boring @ 20'
15-17.5'
17.5-20'
10-12.5'
12.5-15'
5-7.5'
7.5-10'
0-2.5'
2.5-5'
5.8 ppm
1.7 ppm
1.7 ppm
2.1 ppm
1.6ppm
2.1 ppm
1.8 ppm
2.1 ppm
5'
15'
2
2
1
.5
Pyramid Environmental & Engineering, P.C.
FIELD DRILLING RECORD
PROJECT NAME:
PROJECT NUMBER:
BORING/WELL NO:
SITE LOCATION: BORING/WELL
LOCATION:
START DATE: COMPLETED:
GEOLOGIST:DRILLER:
DRILL METHOD: SAMPLE METHOD:
BORING DIA: CASING DIA:
TOTAL DEPTH: CASING DEPTH:
DEPTH
(ft.)
VISUAL MANUAL SOIL CLASSIFICATION
COLOR, TEXTURE, STRUCTURE, CONSISTENCY, ODOR, ETC.
OVA RESULTS
PERCENT RECOVERY
BLOW COUNTS
MONITORING WELL INFORMATION (IF APPLICABLE)
RISER LENGTH (ft) DEPTH (ft) DIAMETER (in) MATERIAL .
SCREEN LENGTH (ft) DEPTH (ft) DIAMETER (in) MATERIAL .
DEPTH TO TOP OF SAND BAGS OF SAND .
DEPTH TO TOP SEAL BENTONITE USED BAGS OF CEMENT USED .
Greensboro Children's Museum MW-8
220 N. Church Street,
Greensboro, NC
Next to fence near building
3/23/2021 3/23/2021
Brian Mahan 3D
Rotary Auger Grab
4'NA
20'N/A
0-5'PVC
5-20'PVC
5
2.5
Brown sandy clayey silt (ML) , dry, slight petroleum odor
Light brown sandy clayey silt (ML), moist, strong petroleum odor
Light brown sandy clayey silt (ML), moist, some petroleum odor
Light brown sandy clayey silt (ML), moist, some petroleum odor
Brown sandy clayey silt (ML) , dry, slight petroleum odor
Light brown sandy clayey silt (ML), moist with white saprolite
strong petroleum odor
Light brown sandy clayey silt (ML), moist with white saprolite
strong petroleum odor
Light brown sandy clayey silt (ML), moist with white saprolite
strong petroleum odor
End of boring @ 20'
17.5-20'
15-17.5'
10-12.5'
12.5-15'
5-7.5'
7.5-10'
0-2.5'
2.5-5'
1.6 ppm
0.9 ppm
1.3 ppm
275 ppm
5.8 ppm
420 ppm
16.5 ppm
904.0 ppm
5'
15'
2
2
1
.5















APPENDIXF

















APPENDIXG

8486889092949602,0004,0006,0008,00010,00012,00014,00016,00018,000BenzeneVs.GroundwaterElevationinMWͲ1BenzeneConc.(μg/L)GroundwaterElevation















APPENDIXH

MOBILE
MULTI-PHASE
EXTRACTION REPORT
SITE LOCATION:
G n C i n M (NCDE In i nt )
N. C St t
G n NC
Prepared For:
P i En i n nt En in in P.C.
P.O. B
G n NC
Pn ( )
November 21, 2022
TABLE OF CONTENTS
x E ENT SUMMAR
x FIELD NOTES
x DISPOSAL MANIFESTS
MOBILE MULTI-PHASE EXTRACTION
EVENT SUMMARY
November 21, 2022
Location: Greensboro Children’s Museum (NCDEQ Incident # 13231)
220 N. Church Street
Greensboro, NC 27401
Client: Pyramid Environmental & Engineering, P.C.
Greensboro, NC
LPT Job Number # 2022-117
Event Date: August 29, 2022 – September 2, 2022
Personnel: Danny Oldham
MMPE System: 300 CFM MMPE System
Extraction Wells: MW-1, MW-8 and MW-10
Well Initial FP Final FP Stinger Depth Run Time
MW S n .
MW .
RW .
Description of Events
T MMPE nt n f . . n A t t . . n S t . T MMPE t ti f
i t . D in t nt t t in f (H ). Eff ti
i i nn t t t MW MW n MW . T t t n f F n it (F) n
t ti i it nt. T t t fi ti ni n f t t i i n
(PPM) t t t nt n MW MW n MW .
Groundwater / Product Mix Recovered:
Din t nt tt f 5,403 gallons of product/water mix f t it in t (MW MW n MW
) n i f t tifi N t C in i f i it . T t t f i n ti
in n t in n f in t nt. B n f ti n n t t f n in t nt
t n t t f t i t t i t 56.28 gallons per hour.
Event Results:
T n f f t i i in t A t MMPE nt. D in t nt t t f n
f t t i n i f t N t C in i f i it . A t t f . n f
n in t i nt. T t t f t i nt t t . n . T t t
nt f in n f t ti t t . n ( . . . n f f
t ).















APPENDIXI

Calculation of ydrocarbon Mass emoval as Gasoline from MMPE Event
S TE Greensboro Childrens Museum DATE
Total Removed to Date from last Spreadsheet:0.00 gallons Date of last Spreadsheet:
Step 2 - Calculate Mass emoval ate for ydrocarbons as Gasoline
Flow elative umidity O A/O M
Date Time ate Temp Temp Temp umidity ws *PPMw std PPMc Cc PM c PM g
(military) (cfm) (deg. F) (deg. C) (deg. R)%(mass ratio)30 (dscfm)**(ppm)(lb/hr) (lb/hr)
8/29/2022 12:30 129.014054 80 26.67 540 90 0.0140 800 124.38 6 4868.15416 0.0001516 1.1317 1.3097
12:45 120.566706 120 48.89 580 95 0.0269 828 106.80 6 5105.33347 0.0001590 1.0191 1.1794
13:00 114.423179 180 82.22 640 95 0.0509 692 89.59 6 4374.67074 0.0001363 0.7325 0.8478
13:15 117.494942 180 82.22 640 95 0.0790 628 89.28 6 4091.20521 0.0001274 0.6826 0.7900
13:30 126.710232 180 82.22 640 95 0.0790 604 96.28 6 3934.85342 0.0001226 0.7081 0.8194
14:00 125.942291 180 82.22 640 95 0.0790 600 95.69 6 3908.79479 0.0001218 0.6991 0.8091
15:00 125.17435 180 82.22 640 95 0.0790 414 95.11 6 2697.0684 0.0000840 0.4794 0.5549
8/30/2022 9:00 152.052278 180 82.22 640 95 0.0790 411 115.53 6 2677.52443 0.0000834 0.5782 0.6691
10;00 143.60493 180 82.22 640 95 0.0790 406 109.11 6 2644.95114 0.0000824 0.5394 0.6243
11:00 149.748456 180 82.22 640 95 0.0790 403 113.78 6 2625.40717 0.0000818 0.5583 0.6461
12:00 151.284338 180 82.22 640 95 0.0790 398 114.95 6 2592.83388 0.0000808 0.5570 0.644713:00 148.212574 180 82.22 640 95 0.0790 397 112.62 6 2586.31922 0.0000806 0.5444 0.6300
14:00 150.516397 180 82.22 640 95 0.0790 395 114.37 6 2573.2899 0.0000802 0.5500 0.6366
15:00 147.444634 180 82.22 640 95 0.0790 389 112.03 6 2534.20195 0.0000789 0.5306 0.6141
16:00 149.748456 180 82.22 640 95 0.0790 385 113.78 6 2508.14332 0.0000781 0.5334 0.6173
17:00 146.676693 180 82.22 640 95 0.0790 381 111.45 6 2482.08469 0.0000773 0.5170 0.5983
8/31/2022 8:00 163.57139 180 82.22 640 95 0.0790 422 124.29 6 2749.18567 0.0000856 0.6386 0.7391
9:00 165.107272 180 82.22 640 95 0.0790 421 125.45 6 2742.67101 0.0000854 0.6431 0.7442
10:00 167.411094 180 82.22 640 95 0.0790 392 127.20 6 2553.74593 0.0000795 0.6071 0.7026
11:00 165.875213 180 82.22 640 95 0.0790 389 126.04 6 2534.20195 0.0000789 0.5970 0.6909
12:00 162.80345 180 82.22 640 95 0.0790 388 123.70 6 2527.6873 0.0000787 0.5844 0.6763
13:00 164.339331 180 82.22 640 95 0.0790 384 124.87 6 2501.62866 0.0000779 0.5838 0.6757
14:00 162.80345 180 82.22 640 95 0.0790 381 123.70 6 2482.08469 0.0000773 0.5739 0.6641
15:00 163.57139 180 82.22 640 95 0.0790 386 124.29 6 2514.65798 0.0000783 0.5841 0.6760
9/1/2022 8:00 162.035509 180 82.22 640 95 0.1148 373 118.33 6 2528.24221 0.0000788 0.5592 0.6471
9:00 161.267568 180 82.22 640 95 0.1343 377 115.18 6 2612.9144 0.0000814 0.5625 0.6510
10:00 164.339331 180 82.22 640 95 0.1386 372 116.79 6 2591.13072 0.0000807 0.5656 0.6546
11:00 162.035509 180 82.22 640 95 0.1222 373 117.34 6 2549.55571 0.0000794 0.5592 0.6471
12:00 162.80345 180 82.22 640 95 0.1343 378 116.27 6 2619.84521 0.0000816 0.5693 0.658913:00 165.107272 180 82.22 640 95 0.1185 399 120.07 6 2715.8253 0.0000846 0.6095 0.7053
14:00 164.339331 180 82.22 640 95 0.1343 377 117.37 6 2612.9144 0.0000814 0.5732 0.6634
15:00 165.107272 180 82.22 640 95 0.1386 375 117.33 6 2612.02693 0.0000814 0.5728 0.6629
16:00 165.107272 180 82.22 640 95 0.1113 377 121.05 6 2545.29087 0.0000793 0.5759 0.6665
9/2/2022 8:00 172.018739 180 82.22 640 95 0.0952 383 128.41 6 2539.7878 0.0000791 0.6095 0.7054
9:00 169.714917 180 82.22 640 95 0.1148 381 123.94 6 2582.46724 0.0000804 0.5982 0.6923
10:00 171.250798 180 82.22 640 95 0.1301 397 122.90 6 2738.24578 0.0000853 0.6290 0.727911:00 173.554621 180 82.22 640 95 0.1343 386 123.95 6 2675.29167 0.0000833 0.6198 0.7173
12:00 172.78668 180 82.22 640 95 0.0867 383 130.19 6 2516.15022 0.0000784 0.6122 0.7086
12:30 162.035509 180 82.22 640 95 0.0840 387 122.45 6 2534.9345 0.0000790 0.5801 0.6714
Step 1 - Calculate apor Flow ate Step 3 - Calculate Total ydrocarbons emoved
E haust E haust E haust Flow System System Total Total
Date Time Diam. Area elocity ate Date Time PM g Operation Operation emoved emoved
(military) (inches)(ft2)(ft/sec) (cfm) (military) (lb/hr) (days) (hours) (lbs) (gallons)
8/29/2022 12:30 3 0.087266 24.64 129.0 8/29/2022 12:30 1.3097 0:00 0.000 0.000 0.000
12:45 3 0.087266 23.03 120.6 12:45 1.1794 0:00 0.250 0.295 0.047
13:00 3 0.087266 21.85 114.4 13:00 0.8478 0:00 0.250 0.212 0.034
13:15 3 0.087266 22.44 117.5 13:15 0.7900 0:00 0.250 0.198 0.032
13:30 3 0.087266 24.20 126.7 13:30 0.8194 0:00 0.250 0.205 0.033
14:00 3 0.087266 24.05 125.9 14:00 0.8091 0:00 0.500 0.405 0.065
15:00 3 0.087266 23.91 125.2 15:00 0.5549 0:00 1.000 0.555 0.089
8/30/2022 9:00 3 0.087266 29.04 152.1 8/30/2022 9:00 0.6691 0:00 18.000 12.044 1.927
10;00 3 0.087266 27.43 143.6 10;00 0.6243 0:00 1.000 0.624 0.100
11:00 3 0.087266 28.60 149.7 11:00 0.6461 1:00 1.000 0.646 0.103
12:00 3 0.087266 28.89 151.3 12:00 0.6447 2:00 1.000 0.645 0.103
13:00 3 0.087266 28.31 148.2 13:00 0.6300 3:00 1.000 0.630 0.101
14:00 3 0.087266 28.75 150.5 14:00 0.6366 4:00 1.000 0.637 0.102
15:00 3 0.087266 28.16 147.4 15:00 0.6141 5:00 1.000 0.614 0.098
16:00 3 0.087266 28.60 149.7 16:00 0.6173 6:00 1.000 0.617 0.099
17:00 3 0.087266 28.01 146.7 17:00 0.5983 7:00 1.000 0.598 0.096
8/31/2022 8:00 3 0.087266 31.24 163.6 8/31/2022 8:00 0.7391 8:00 15.000 11.086 1.774
9:00 3 0.087266 31.53 165.1 9:00 0.7442 9:00 1.000 0.744 0.119
10:00 3 0.087266 31.97 167.4 10:00 0.7026 10:00 1.000 0.703 0.112
11:00 3 0.087266 31.68 165.9 11:00 0.6909 11:00 1.000 0.691 0.111
12:00 3 0.087266 31.09 162.8 12:00 0.6763 12:00 1.000 0.676 0.108
13:00 3 0.087266 31.39 164.3 13:00 0.6757 0:00 1.000 0.676 0.108
14:00 3 0.087266 31.09 162.8 14:00 0.6641 0:00 1.000 0.664 0.106
15:00 3 0.087266 31.24 163.6 15:00 0.6760 0:00 1.000 0.676 0.1089/1/2022 8:00 3 0.087266 30.95 162.0 9/1/2022 8:00 0.6471 0:00 17.000 11.001 1.760
9:00 3 0.087266 30.80 161.3 9:00 0.6510 0:00 1.000 0.651 0.104
10:00 3 0.087266 31.39 164.3 10:00 0.6546 0:00 1.000 0.655 0.105
11:00 3 0.087266 30.95 162.0 11:00 0.6471 0:00 1.000 0.647 0.104
12:00 3 0.087266 31.09 162.8 12:00 0.6589 0:00 1.000 0.659 0.105
13:00 3 0.087266 31.53 165.1 13:00 0.7053 0:00 1.000 0.705 0.113
14:00 3 0.087266 31.39 164.3 14:00 0.6634 0:00 1.000 0.663 0.106
15:00 3 0.087266 31.53 165.1 15:00 0.6629 0:00 1.000 0.663 0.106
16:00 3 0.087266 31.53 165.1 16:00 0.6665 0:00 1.000 0.666 0.107
9/2/22 8:00 3 0.087266 32.85 172.0 9/2/2022 8:00 0.7054 0:00 16.000 11.286 1.806
9:00 3 0.087266 32.41 169.7 9:00 0.6923 0:00 1.000 0.692 0.111
10:00 3 0.087266 32.71 171.3 10:00 0.7279 0:00 1.000 0.728 0.116
11:00 3 0.087266 33.15 173.6 11:00 0.7173 0:00 1.000 0.717 0.115
12:00 3 0.087266 33.00 172.8 12:00 0.7086 0:00 1.000 0.709 0.113
12:30 3 0.087266 30.95 162.0 12:30 0.6714 0:00 0.500 0.336 0.054
E
Total hydrocarbon vapors removed as gasoline (this event) 10.50 gallons * See Psychrometric Calculators at:Field Data
Total hydrocarbon vapors removed as gasoline (this event) 65.62 pounds http://www.rezine.net/WebCalcs/Psy/webpsyx.htm From Web
or http://www.learninghelper.com/psyc Int. Calc.
Total hydrocarbon vapors removed as gasoline (previous events) 0.00 gallons Transferred
** For OVA (FID) calibrated with Methane, K=1; Results
Total hydrocarbon vapors removed as gasoline (to date) 10.50 gallons For OVM (PID) calibrated with Hexane, K=6.Previous
Calculations based on NCDENR - UST Section Guidelines - Appendix B, Pages B-74 to B-75
11/21/2022
N/A















APPENDIXJ


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