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EnvironmentalRisk Management, Inc.Fort Myers, Floridapresented byStephen Hilfikerwww.ermi.netEnvironmental Forensic Investigations
Environmental Forensics“Before you invest, investigate”William Arthur WardAmerican scholar, author, pastor and teacher (1921-1997).
What is Environmental Forensics?“The application of scientific methods used to identify the origin and timing of a contaminant release”A global science practiced throughout the worldUniversity Programs offering undergraduate and graduate degreesJournal of Environmental Forensics $90/year - electronicInternational Society of Environmental Forensics (ISEF)www.environmentalforensics.org
What is the chemical pollutant?What is the source? Time of release?Who is to responsible? [Liability]What is my cost? [Apportionment] Global Perspective Different Contaminants & Environment
Two Forensic SeminarsNew Release InvestigationsCost Allocation
Investigative ProcessSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillSpillTraditional Data AnalysisSpillWhat, When, Who
Mixed plume sitesPetroleum release datingDischarge source identificationFunding allocationInsurance claim investigationSolvent degradation studiesLitigation support/preventionForensic Tool Applications
Mixed Plume Sites
Basic Chemistry in ForensicsIdentify contaminantsIdentify breakdown productsDetermine potential sourcesFull consideration of all possible scenarios
Disputes over liability.Subjective opinions.Secondary discharges are a challenge.Limited data.Burden of proof.Allocating responsibility.Forensic assessments needed.The Issues
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
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 AnalysesDendroecologyRatio, 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
Forensic Assessment ToolsSame site, different well…The Before ConditionNote a,a,a -TFT (system monitoring compound)
Same site different well.The After Condition.Note TolueneForensic Assessment Tools
Case StudyService Station Site, 30 Year HistoryTwo Major Fuel Brands Numerous Suspected DischargesIon Fingerprint Detection Software Indicates One Discharge Background File Review Explains Other Spikes. A Combination of Forensic and Consulting Services Establishes Position
Case Study- Mixed PlumeEast sideRecent releaseBasis: alkyl benzenes detected with softwareBTEX to C3 benzenes ratio: 1.87Late 1990’s, 5-7 year old spillSupports analytical historyWest sideOld releaseBasis: software formed non-target componentsBTEX to alkylated benzene ratio: 0.1220 or more year old spillFunding allocation site
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
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
PIANO AnalysisParaffin, Isoparaffin, Aromatic, Naphthene, Olefin High Resolution Composition AnalysisGives a detailed fingerprint of specific hydrocarbons and is useful in product type identification: higher aromatic = higher octaneUseful in estimating amount of weathering
Forensic Science relies on an arsenal of tools.Success will be obtained from multiple, but independent lines of evidence.There are numerous emerging and established techniques.Combining forensic methods can give a result that is less vulnerable to scientific dispute.Conclusion
Questions?Contact Information:Steve HilfikerEnvironmental Risk Management, Inc.email@example.com-ENV-MGMT (368-6468)