DJ Basin Crude Oil Flammability Analysis

DJ Basin Crude Oil Flammability Analysis

Background Alignment of the OSHA Hazard Communication Standard (HCS) with the Globally Harmonized System of Classification and Labeling of Chemicals (GHS). Required evaluation of chemical hazards

Background North Dakota Industrial Commission crude oil stabilization requirements Prior to shipment by rail, crude oil must be stabilized (volatile components removed) to a Total Vapor Pressure less than 13.7 psia

Background EPA/CDPHE Fugitive Emission Regulations Elimination of fugitive emissions from tanks caused an increase in flammable/toxic vapors present in tanks resulting in worker exposure and increased vapor fires (OSHA Hazard Alert)

Crude Flammability Study 3 producers -BBC -Great Western Oil & Gas -PDC Energy 16 crude oil samples from 12 production facilities 4 corresponding tank headspace and crude oil true vapor pressure (TVP) sample locations Study area 78 miles x 84 miles 1S to 12N and 61W to 68W Mid-2011 to mid-2014 first production Niobrara and Codell horizontals 5

Approximate Sample Locations 6

Crude Flammability Study Boiling point by ASTM D2887 Flammability (flash point) by ASTM D93 Headspace volatile organic compounds (VOCs) by EPA TO-15 TVP by ASTM D6377 7

FP and BP Sample Results 15 samples had flash point below 50 deg F 1 sample had flash point below 70 deg F Wide variability in boiling points 20% BP 151-295ºF No correlations based on geography, formation, or age of well 8

TVP Sample Results All four samples had TVP below 13.7 psia threshold recently established by NDIC for Bakken crude Samples ranged from 6.04 to 11.05 psia No correlation to 20% BP, however a correlation between age of well and TVP was observed Older wells had lower true vapor pressures 9

VOC Sample Results VOC concentrations in tanks exceeded OSHA PELs but did not exceed IDLH concentrations Wide variability head space vapor composition No apparent correlations to boiling point, age of well, or geographic location 10

Crude Classification Results indicate crude is: Class IB flammable liquid (NFPA 30)* Class 3 flammable liquid (DOT - 49 CFR 173.120) Flammable liquid (OSHA - 29 CFR 1910.106(a)(19)) Crude oil tanks should be labeled with NFPA 704 label (aka NFPA diamond) flammability rating of 3 Crude oil meets requirements of NDIC Order No. 25417 - oil conditioning order * Per Section 4.2.1.2 of NFPA 30 the 20% boiling point of the distillation analysis is used for characterization 11

Data Analysis

Data Analysis Bill Barrett Corporation, Great Western Oil and Gas and PDC each contributed samples to the study Identifying data masked to provide confidentiality Well name not provided Location limited to Township and Range Spud date limited to quarter and year 13

Results Summary Boiling Point Sample ID Flash Point Initial Boiling Point 5% 10% 20% 30% 40% 50% 60% 70% 80% 90% 95% Full Boiling Point 1 <50 56.5 110.9 183.4 267.0 337.0 427.3 512.7 591.9 671.4 766.1 858.1 903.5 962.9 2 <50 52.2 85.2 152.2 233.1 307.5 389.1 477.5 560.5 645.2 740.1 840.4 892.8 961.8 3 <50 62.5 186.1 235.8 295.5 368.7 441.3 512.2 587.8 666.9 758.5 861.7 914.4 984.2 4 <70 62.4 177.8 205.1 282.4 347.7 426.7 499.6 572.9 659.9 749.0 852.6 910.2 982.7 5 <50 51.8 61.9 84.6 165.9 204.6 266.5 315.6 388.5 481.9 575.2 715.2 823.0 923.1 6 <50 51.9 84.7 139.2 204.8 266.6 322.5 395.5 481.9 569.8 666.4 795.3 875.0 953.9 7 <50 51.9 84.8 139.2 229.0 290.5 352.4 437.4 511.8 592.8 689.0 799.8 873.6 952.9 8 <50 51.9 84.8 139.2 221.4 282.3 336.2 420.7 499.5 579.0 670.6 781.5 852.3 934.6 9 <50 61.8 138.7 190.1 250.6 313.8 381.7 465.2 539.3 630.5 728.8 839.3 902.2 982.5 10 <50 51.8 62.0 84.7 177.4 204.7 266.5 313.9 376.7 450.3 539.4 647.7 727.4 852.1 11 <50 51.7 84.5 128.5 197.5 261.2 322.3 403.5 481.7 569.4 666.1 781.2 852.0 934.4 12 <50 51.8 66.9 109.9 177.4 204.6 250.8 295.5 359.0 450.3 539.3 670.3 758.0 888.9 13 <50 55.9 84.8 151.3 228.9 285.0 352.2 438.8 511.6 597.6 688.8 799.6 862.8 937.9 14 <50 51.8 84.7 139.1 204.7 270.6 330.2 414.4 496.9 581.8 674.1 787.2 860.7 937.8 15 <50 51.8 61.9 84.5 151.1 197.3 241.5 282.1 330.6 403.7 481.5 592.5 674.1 883.4 16 <50 51.9 67.0 110.0 190.3 237.6 292.5 356.1 437.1 511.6 603.1 712.5 787.3 883.4 NOTES: All temperatures are in degrees Fahrenheit < - less than 14

Boiling Point Analysis

Results Summary - TVP Sample ID TVP (psia @ 100ºF) 20% BP (ºF) Spud Date 1 6.04 267.00 Q4 2011 2 7.07 233.10 Q3 2013 3&4 11.05 288.90 Q1 2014 5&6 10.90 185.35 Q1 2014 16

Results Summary - VOCs Compound Unit Site 1 Site 2 Site 3 & 4 Site 5 & 6 IDLH 10% LEL Methylene Chloride ppm 25 30 -- -- 5,000 13,000 Hexane ppm -- 730 2,100 740 5,000 1,100 Benzene ppm 610 140 380 73 3,000 1,200 Cyclohexane ppm 910 170 520 150 10,000 1,300 Heptane ppm 1,000 170 440 140 5,000 1,050 Toluene ppm 360 76 140 32 2,000 1,100 Chlorobenzene ppm 14 -- -- -- 2,400 1,300 Ethyl benzene ppm 34 4.3 9.3 1.9 2,000 800 m,p-xylene ppm 35 5.9 13 5.2 1,000 900 o-xylene ppm 15 2.7 5.4 -- 1,000 900 1,2,4-Trimethylbenzene ppm 2.5 -- -- -- NL NL Propane ppm 570 780 540 510 20,000 2,100 Isobutane ppm 390 560 400 650 NL NL Cyclopropane ppm -- -- 600 -- NL NL Butane ppm 630 890 -- 880 19,000 1,900 Butane, 2-methyl- ppm 450 480 430 570 NL NL Pentane ppm 450 520 440 560 15,000 1,500 Pentane, 2-methyl- ppm 200 160 200 180 NL NL Pentane, 3-methyl- ppm -- 84 110 83 NL NL Cyclobutane, methyl- ppm -- -- 110 79 NL NL Cyclopentane, methyl- ppm 170 130 140 87 NL NL Cyclopentane, 1,2,3-trimethyl- ppm 210 -- -- -- NL NL Hexane, 2-methyl- ppm -- -- -- 53 NL NL Hexane, 3-methyl- ppm -- 66 -- 71 NL NL Hexane 2,5-dimethyl- ppm -- 68 -- -- NL NL Heptane, 2-methyl- ppm 410 -- 140 -- NL NL Heptane, 3-methyl- ppm 150 -- -- -- NL NL Cyclohexane, methyl- ppm 170 110 140 100 10,000 1,200 Cyclohexane, 1,2-dimethyl- ppm 230 -- -- -- NL NL Cylcohexane, 1,3-dimethyl-, trans- ppm -- -- 110 -- NL NL Octane ppm 290 -- 100 -- 5,000 1,000 NOTES: ppm = parts per million -- = not detected IDLH = immediately dangerous to life and health LEL = lower explosive limit NL = not listed 17

Results Summary - LEL Mixture LEL ranges from 11500 ppm to 15360 ppm Average LEL = 12250 ppm Methane LEL = 10000 ppm

Boiling Point Analysis

Boiling Point Analysis

Boiling Point Analysis

Head Space Composition Tank Head Space VOC Composition 2,500 Site 1 2,000 Site 2 Concentration (ppm) 1,500 1,000 Site 3 & 4 Site 5 & 6 500 0