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Presentation Slides & Transcript
Presentation Slides & Transcript
Presented byStephen F. Hilfiker, MS, PresidentEnvironmental Risk Management, IncFort Myers, Floridaermi.netEnvironmental Forensics andFlorida’s Leak Autopsy Study for ASTsNational Institute for Storage Tank ManagementAnnual Conference May 11, 2005
Acknowledgements…Marshall T. Mott-Smith, AdministratorStorage Tank Regulation SectionBureau of Petroleum Storage SystemsFlorida Department of Environmental ProtectionCarol Carnley Storage Tank Regulation/Registration Florida Department of Environmental Protection
Autopsies + Forensics = CSIContaminant Spill InvestigationWhat was spilled?Where was it spilled?Why was it spilled?When was it spilled?Who is responsible for the spill?
au·top·sy (ô’ tŏp sē)source: dictionary.comExamination of a cadaver to determine or confirm the cause of death. Also called necropsy, postmortem, postmortem examination. A critical assessment or examination after the fact: a post-election campaign autopsy.
Leak Autopsy ProgramFlorida’s leak autopsy program is “a critical assessment or examination after the fact” that collects information to help answer the who, what, why, where and when of a spill.“Snapshot” – limited studyReview leak autopsy resultsDiscuss new release issueOverview of environmental forensics
Data set is 359 autopsy reports covering 6/1997 to 3/2005 (UST and AST reports)Source data provided by Florida DEP“Invalid” reports excludedUST data excluded (attend November 9-10, 2005 NISTM UST conference)Excel data processed through additional software to manage multi-value fieldsLeak Autopsy ReviewMaterials and Methods
Leak Autopsy ReviewTo identify the extent, scope and applicability of data derived through review of autopsy forms.To prevent future leaks.To identify where we should focus our resources.Goals
Leak Autopsy FormPage 1Page 2
Leak Autopsy FormPage 3Page 4
Autopsy: Where?Top ten counties (recorded AST autopsy forms)
Distribution of AST Autopsy Reports
Autopsy: Cause of Discharge
Discharge CauseField Erected
Discharge CauseShop Fabricated
Discharge CauseField Erected versus Shop Fabricated
Autopsy: Discharge Source
Discharge SourceField Erected
Discharge SourceShop Fabricated
Discharge SourceField Erected versus Shop Fabricated
Autopsy: Discovery Method
Discovery MethodField Erected
Discovery MethodShop Fabricated
Environmental Forensics“Before you invest, investigate”William Arthur WardAmerican scholar, author, pastor and teacher (1921-1997).
Investigative ProcessSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillLeak Autopsy Data AnalysisSpillWhat, When, Who
Forensic Assessment Tools
Second discovery of the original discharge? Were there unreported/multiple discharges?Has the old discharge migrated?When did the new discharge occur?Who is responsible and for how much?ECONOMICALLY SIGNIFICANT DIFFERENCES OF OPINION…Challenging Questions
Disputes over liability.Subjective opinions.Secondary discharges are a challenge.Limited data.Burden of proof.Allocating responsibility.Forensic assessments needed.The Issues
Mixed plume sitesPetroleum release datingDischarge source identificationFunding AllocationInsurance Claim InvestigationSolvent degradation studiesLitigation support/preventionForensic Tool Applications
Mixed Plume Sites
Source AbatementHistorical and Regulatory ResearchSite and Study Area InvestigationsDiligence: Overcome Data LimitationsDefine Objectives and Assumptions, PhasesSelect Forensic ToolsEvaluate and Opine Based on FactsThe Forensic Process
Court defensible data can be costly. How much to invest to prevent or support litigation?Choosing Different TechniquesDiligent assessments, as usual, are the key to an effective solution.There are many tools available.
Forensic ToolsResearch backgroundChromatographyGC/MS AnalysisForensic FingerprintingComposition AnalysesIsotope AnalysesTime of Travel AnalysisRatio, Cluster and Target AnalysesGW Modeling
Release Detection: .2 gph If undetected: 4.8 gpd, up to 1752 gpy1980’s laws based on 1960’s technologyCleanup Target Levels: Benzene: 1 ug/L 0.12 – 3.5% of gas by weight (LUFT, 1988)Assume undetected, steady leak of 1000 gals per year and 2.5% Benzene: 25 gals At 1 ppb, this is a significant concern…Standards
a chromatogram review…Gas Chromatography (GC)Sample of dissolved chemicals is heated.Chemicals vaporize at different rates.Abundance and time of evaporation is recorded and graphed.
a chromatogram review…Gas Chromatography (GC)Fresh (more volatile)Note the high level volatiles (left side = vaporize faster, lighter, more mobile).
a chromatogram review…Gas Chromatography (GC)Chromatogram of weathered gasoline.The volatiles are gone; the heavier, less volatile constituents remain.
ReboundCase Study #1:The system was turned off. Post remedial monitoring = spike. New release suspected. The remediation was effective. Research demonstrated rebound.
The Before Condition(Ignore surrogates on left half)
The After Condition(Similar spectral signature/uniformity)
MigrationChanges in water levels and smear zone influencesEffects of remedial system (pumping out creates drawdown, pumping in creates mounding; injecting air can push)Synthetic lithology around tanksThe trapped source within tank area.Bioremedial desorptionMany Causes of Variable Data(it is not always new)
An unexplained increase in dissolved hydrocarbon concentrations in wells surrounding an underground storage tank caused suspicion of a new release.Chromatography research concludes a new release has occurred.Case Study #2:New Release
The Before ConditionWeathered pattern, Benzene > MTBE
The After ConditionFresh pattern, MTBE > Benzene
Figure 1: Chromatogram of undegraded DieselFigure 2: Analysis run through the softwareMass Spectrometry Fingerprinting Software
Forensic FingerprintingIdentify specific compounds to source petroleum, distinguish pathways and release eventsStandard EPA/State volatile vs. semi-volatile target compounds Unique brand components (such as additives, detergents)Biomarkers to assess weathering patternObjectives:
ObjectiveKey indicator compounds are revealed through deconvolution software for fingerprinting or aging by finding biomarker or specific brand additives.Target Compounds can be positively identified in peaks that contain more than one compound, a process known as speciation.
Customized MethodColor coded, user specified compounds.Method 8260 (EPA) Target CompoundsExample: former major brand site; patented research; additives...find non target Compounds
Distinguish Spectral SignatureGasoline, Kerosene, Diesel, Heating Oil, Aviation FuelCompound specific analysis to unmask petroleum source by other components in the mixture
Preliminary ProcedureGroundwater SamplingAgilent GC/MS 8260 & 8270∙d format input to software
Deconvolution AlgorithmsComplicated mass spectra from coeluting compounds are separated by deconvolution algorithmsSignalTimeMS ResponseGC Separation
How Algorithms Work All ions are compared by relative response across the GC peak. When coeluting compounds have a common ion, the algorithms subtract the additive contribution and then compare against what the response should be via the method library.
Typical VOC Chromatogram
Deconvoluted VOC Chromatogram
Typical SVOC Chromatogram
Deconvoluted SVOC Chromatogram
Paraffin, Isoparaffin, Aromatic, Naphthene, Olefin High Resolution Composition AnalysisGives a detailed fingerprint of specific hydrocarbons (P = ~10%, I = ~ 35%, A = ~ 44%, N = ~ 5%, O = ~ 6%) and is useful in product type identification: higher aromatic = higher octaneUseful in estimating amount of weathering PIANO Analysis
1.5 to 6 is generally new or close to the source<0.5 is usually indicative of an older releaseEvaluate the affinity for degradation at sitePlot data over time across the siteB + T / E + XQualitative DiscriminationT/B, E/B, X/B, E/T, X/T, and E/X on scatter plotRatio Analysis
Questions?Contact Information:Steve Hilfikershilfiker@ermi.net1-888-ENV-MGMT(1-888-368-6468)