??? Francine Kelly-Hooper, PhD, Soils Scientist CH2M HILL Canada RemTech Conference, Banff Alberta

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1 Biogenic Interference Calculation (BIC) Index for Resolving False Exceedences of AB Tier-1 F3 PHC Soil Guidelines Due to Biogenic Interferences in Peat Soils Francine Kelly-Hooper, PhD, Soils Scientist CH2M HILL Canada 2016 RemTech Conference, Banff Alberta Alberta Peatlands False PHC detections in peat soils surrounding an oil spill =??????

2 What is the BIC Index? Pronounced BIC like the pen Calculation for determining if biogenic interferences have caused organic (peat) samples to falsely exceed the Alberta Tier-1, 300 mg/kg F3 PHC soil guideline. [F2/(F2+F3b)] x 100 <10% = false PHC exceedence >10% = true PHC exceedence

3 BIC Index Continues to Evolve After 14 Years of Research Continuing method development

4 Research Partners (Village that Raised the BIC Index) Alberta Parks and Protected Areas Division ALS Laboratory Group Husky Energy Imperial Oil Canadian Association of Petroleum Producers Environment Canada Oil Spills Research Centre Canadian Geological Survey Natural Sciences and Engineering Research Council Orphan Well Association Petroleum Technology Alliance of Canada University of Waterloo

5 STUDY OBJECTIVES Comparison of Control Experiment Data to Field Validation Data To determine if the BIC Index will correctly identify samples that have or have not falsely exceeded the most stringent Alberta Tier 1 F3 PHC soil guideline (300 mg/kg) in all clean and contaminated soil samples

6 Controlled Training Data Sources

7 Data Set #1: 300-Day Crude Oil Spiked Peat PhD Experiment Clean peat and sand were spiked with crude oil and studied for biogenic vs petrogenic carbon distributions over time.

8 Data Set #2: 300-Day Diesel Spiked Manure PhD Experiment Compost and sand were spiked with diesel drilling invert and studied for biogenic vs petrogenic carbon distributions over time.

9 Field Validation Data Sources

10 Data Set #3: Background PHC survey of 34 sites located in Alberta, BC and Newfoundland Canadian Geological Survey collected 34 background soil samples for the biogenic vs petrogenic carbon distribution study

11 Data Set #4: Orphan Well Association Field Validation Site The OWA collected 55 samples from a 35-year old crude oil contaminated Alberta peatland for the biogenic vs petrogenic carbon distribution study.

12 What are biogenic organic compounds (BOCs)? BOCs are carbon-based compounds, which are naturally biosynthesized by living organisms. BOC groups containing C, H and O include: lipids, carbohydrates, proteins and nucleic acids. BOC hydrocarbon groups containing only C and H include n-alkanes.

13 Canadian Council of Ministers of the Environment (CCME) Reference Method for the Canada-Wide Standard (CWS) for Petroleum Hydrocarbons (PHC) in Soil Methods can produce false positives in uncontaminated organic materials (e.g. peat, manure, etc.).

14 The problem is that the hexane and acetone solvents indiscriminately extract all carbon from petroleum and biological sources. The goal is to capture petroleum hydrocarbons. However, background biogenic organic compounds are inadvertently captured as well.

15 GC-FID Analysis of Sample Extract carrier gas line Extract injection Vaporizer Oven flame Flame Ionization Detector ion flow )))))))) detector electronic signal F2, F3, F4 concentrations quantified by chromatogram integrations capillary column

16 Diesel-Spiked Peat GC-FID Chromatogram F2 C10-C16 F3 C16-C34 F4 >C34 pa Diesel F mg/kg Reported F mg/kg Peat F mg/kg UCM Retention Time (minutes)

17 Classification of Petroleum Hydrocarbon Sources by Carbon Number Range F1 F2 F4 C6-C10 C10-C16 C16-C34 > C34 F3 Gasoline Biogenic Organic Compounds (e.g. fatty acids, sterols, waxes, etc. ) Diesel/No. 2 Fuel Oil No. 6 Oil/Lube Oil/Heavy fuels, Tar, Asphalts Crude Oil C6 C10 C16 C34 >C34 Carbon Numbers

18 Comparison of Background Soil Survey Results to Alberta Tier-1 Soil and Groundwater Remediation Guidelines

19 Alberta Tier-1 Soil Remediation Guidelines Coarse textured soil remediation guidelines may be used for organic contaminants in organic soils

20 34 Background Soil Samples: Alberta, BC, Newfoundland Comparisons of F2, F3, F4 Concentrations to AB Tier-1 Soil Remediation Guidelines Surface Soils Natural/Agricultural/Residential/Parkland Guidelines F2 (mg/kg) mg/kg 0 samples exceeded F2 course soil standards F3 (mg/kg) mg/kg 16 samples (47%) exceeded F3 coarse soil standard 0 F4 (mg/kg) mg/kg 0 samples exceeded F4 course soil standards 0 0% 10% 20% 30% 40% %TOC

21 34 Background Soil Samples: Alberta, BC, Newfoundland Comparisons of F2, F3, F4 Concentrations to AB Tier 1 Soil Remediation Guidelines Surface Soils Natural/Agricultural/Residential/Parkland Guidelines F2 (mg/kg) mg/kg Only F3 exceeded the guideline 0 samples exceeded F2 course soil standards 1600 F3 (mg/kg) mg/kg 16 samples (47%) exceeded F3 coarse soil standard 0

22 All soils with >28% TOC exceeded the F3 coarse soil standards Peat soils have >40% TOC

23 Peat soils cover 18% of Alberta source: Alberta Geological Survey

24 But there is a light at the end of the tunnel!

25 Biogenic Interference Calculation for Identifying False Exceedences of the AB Tier-1, F3 PHC 300 mg/kg Soil Guideline Formula [F2/(F2+F3b)] x 100 F2 = measured F2 (C10-C16) concentration F3b = measured F3b (C22-C34) concentration Index Values <10% indicates that BOCs have caused false exceedences of F3 PHC guideline >10% indicates true exceedences of the F3 PHC guideline

26 F3a (C16-C22) and F3b (C22-C34) Distributions in Diesel and Clean Peat F2 Total F3 F4 Clean Peat Non-detectable F2 F3a (C16-C22) F3b (C22-C34) 7% F3a 93% F3b Diesel Contaminated Peat Detectable F2 F3a 37% F3b 63% Detectable F2 11% F3b 89% F3a Diesel C10 C16 C22 C34 Carbon Number

27 F3a (C16-C22) and F3b (C22-C34) Distributions in Crude Oil and Clean Peat F2 Total F3 F4 Non-detectable F2 F3a (C16-C22) F3b (C22-C34) 7% F3a 93% F3b Peat Crude + Peat Detectable F2 31% F3a 69% F3b Federated Crude Oil Detectable F2 50% F3a 50% F3b C10 C16 C22 C34 Carbon Number

28 13 Fresh Crude Oil Samples 34 Background Soil Samples Median Median F3a 49% F3b 51% F3a 7% F3b 93% % of Total F3 Concentration Crude Oil Samples % of Total F3 Concentration Soil Samples F3a (C16-C22) F3b (C23-C34) F3a (C16-C22) F3b (C23-C34)

29 F2, F3, F4, F3a, F3b Carbon Distributions in PHC Products and Clean Peat Diesel Fuel F3a F3b High F3a F3a 89% F3b 11% Crude Oil High F3a 47% F3a 53% F3b Engine Oil Low F3a 6% F3a 94% F3b Tar Low F3a 14% F3a 86% F3b Peat 7% Low F3a F3a 93% F3b F2 F3 F4

30 Example of BIC Index for Diesel PHCs F2 F3b [F2/F2+F3b] x 100 Clean Peat F2 = 10 mg/kg F3b = 1,395 mg/kg 1% = Guideline not Exceeded Diesel Spiked Peat F2 = 613 mg/kg F3b = 2,816 mg/kg 33% = Guideline Exceedence Diesel F2 = 823 mg/kg F3b = 371 mg/kg C10 C16 C22 C34 Carbon Number Total F3 69% = Guideline Exceedence

31 Example of BIC Index for Crude Oil PHCs F2 F3b [F2/F2+F3b] x 100 Clean Peat F2 = 10 mg/kg F3b = 1,000 mg/kg 1% = Guideline not Exceeded Crude Oil Spiked Peat F2 = 1,000 mg/kg F3b = 2,000 mg/kg 33% = Guideline Exceeded Crude Oil F2 = 1,000 mg/kg F3b = 1,200 mg/kg 45% = Guideline Exceeded C10 C16 C22 C34 Carbon Number Total F3

32 BIC Index Decision Tree for Identifying False Exceedences of AB Tier-1 F3 PHC 300 mg/kg Soil Guideline Pre-screening criteria: only include samples that meet these criteria 1) F2 concentration is less than laboratory method detection limit (<20 mg/kg) 2) F3 concentration exceeds the 300 mg/kg guideline, F4 concentration does not exceed any guidelines 3) The released PHC product(s) must extend into the light F2 (C10-C16) carbon range (e.g. diesel, crude oil, etc.) 4) A qualified person must confirm that the GC-FID chromatogram does not have a heavy PHC pattern (e.g. asphalt, bitumen, motor oil, etc.). Does the GC-FID chromatogram image have an obvious Unresolved Complex Mixture (UCM) petrogenic pattern? No Yes Heavy PHCs may be present (Do not proceed with the evaluatio) Is the Biogenic Interference Calculation >10%? No Indicates false exceedance of F3 PHC guideline Yes Indicates true exceedance of F3 PHC guideline

33 BIC Index Testing of Control Samples: Clean and Spiked Soil and Compost Biogenic Interference Calculation > 10% indicates true F3 PHC guideline exceedences <10% indicates false F3 PHC guideline exceedences Peat spiked with crude oil; compost spiked with diesel invert Clean soils and compost

34 BIC Index Testing of Control Samples: Clean and Spiked Soil and Compost BIC Index correctly identified true F3 PHC guideline exceedences in all crude oil and diesel spiked samples Biogenic Interference Calculation > 10% indicates true F3 PHC guideline exceedences BIC Index correctly identified false F3 PHC guideline exceedences in all clean samples <10% indicates false F3 PHC guideline exceedences Peat spiked with crude oil; compost spiked with diesel invert Clean soils and compost

35 Field Validations of 37 Year Old OWA Crude Oil Contaminated Peatland Biogenic Interference Calculation > 10% indicates true F3 PHC guideline exceedences <10% indicates false F3 PHC guideline exceedences Peat samples with detectable F2 and >300 mg/kg F3 concentrations Peat samples with non-detectable F2 and >300 mg/kg F3 concentrations

36 Field Validations of 37 Year Old OWA Crude Oil Contaminated Peatland Biogenic Interference Calculation All samples with >300 mg/kg F3 and non-detectable F2 concentrations were identified as false PHC guideline exceedences > 10% indicates true F3 PHC guideline exceedences <10% indicates false F3 PHC guideline exceedences All samples with >300 mg/kg F3 and detectable F2 concentrations were identified as true PHC guideline exceedences Peat samples with detectable F2 and >300 mg/kg F3 concentrations Peat samples with non-detectable F2 and >300 mg/kg F3 concentrations

37 BIC Index Statistical Probability Test Results The BIC Index is a highly conservative/cautious tool. 0% probability of missing true exceedences. 10% probability of missing falseexceedences.

38 Next Steps? CH2M is currently expanding the BIC Index to include heavy PHCs (e.g. asphalt, bitumen, motor oil, etc.) as well.

39 Francine Kelly-Hooper