Document 4azZYJjn8861b9RB1a4aYQwzV
Chord Energy Corporation - Various Well Pads Partial Compliance Evaluation (PCE)
On-Site Clean Air Act (CAA) Inspections
Inspection Date(s):
October 23-24, 2024
Inspection Report Date:
December 27, 2024
EPA Representatives:
Katelyn Bergl, US EPA Region 8, Clean Air Act Inspector Youn Joo Kim, US EPA Region 8, Clean Air Act Inspector Taylor Waanders, US EPA Region 8
Tribal Representatives:
Dwight Bruce, MHA Energy
Company Representatives: None
Inspection Report Prepared By:
Katelyn Bergl, US EPA Region 8, Clean Air Act Inspector Youn Joo Kim, US EPA Region 8, Clean Air Act Inspector
Inspection Report Reviewed By:
Applicable Rules:
Scott Patefield, Manager, Enforcement and Compliance Assurance Division, Air and Toxics Enforcement Branch
SCOTT PATEFIELD Date: 2024.12.27 14:00:35 -07'00' Digitally signed by SCOTT PATEFIELD
40 C.F.R Part 49, Subpart K - Federal Implementation Plan for Oil and Natural Gas Well Production Facilities; Fort Berthold Indian Reservation (Mandan, Hidatsa and Arikara Nation), North Dakota (Fort Berthold FIP)
40 C.F.R. Part 60, Subpart OOOO - Standards of Performance for Crude Oil and Natural Gas Facilities for Which Construction, Modification, or Reconstruction Commenced After August 23, 2011, and on or Before September 18, 2015 (NSPS OOOO)
40 C.F.R Part 60, Subpart OOOOa - Standards of Performance for Crude Oil and Natural Gas Facilities for which Construction, Modification or Reconstruction Commenced After September 18, 2015 (NSPS OOOOa)
Compliance Assistance None
Enforcement History None
Areas of Concern 1. The EPA detected hydrocarbon emissions from the storage tanks co-located with the following well: Independence 16-31B
2. The EPA detected unburned hydrocarbon (UBHC) emissions from an operating utility flare at the following well pad: Bullwinkle Pad 15-4D
3. The EPA detected visible emissions from operating utility flares at or co-located with the following wells or well pads: MHA 3-32-29H-150-91 MHA 6-06-01-H-149-92 Independence 16-31B MHA 1-06-01H-149-92 Skunk Creek Pad 13-3D Bullwinkle Pad 15-4D Buffalo Pad 10-06D
See Table 1 below for more details regarding inspected locations and Tables 2 and 3 for inspection observation details for all pads. A log of images and videos captured during the inspections is provided in Appendix A.
General Inspection Information Unannounced well pad inspections were conducted jointly by U.S. EPA and Fort Berthold Indian Reservation (FBIR) Tribal inspectors on October 23, and 24, 2024, at multiple Chord Energy Corporation (Chord) facilities located on the Fort Berthold Indian Reservation (FBIR). The inspected facilities were previously owned and operated by Oasis Petroleum Inc. (Oasis) and began operating under the Chord Energy name on July 1, 2022 after a merger was completed between Oasis and Whiting Petroleum Corporation to form the new company, Chord Energy Corporation.
The EPA inspectors evaluated each well site listed in Table 1 using audio, visual, and olfactory (AVO) inspection methods including the use of an optical gas imaging (OGI) camera and EPA Reference Method 22. At each facility, inspectors scanned the crude and/or water storage tanks, closed vent system and flares onsite for any detectable emissions. Specifically, inspectors scanned storage tank covers and closed vent systems for hydrocarbon emissions to determine compliance with the Clean Air Act, including the Fort Berthold FIP and NSPS OOOO/a.
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Each well pad inspection followed the approach below:
1. Record the entry sign of the well pad when available. Survey the entire well pad with OGI camera.
2. Record the number and type of site process equipment such as well heads, tanks, and emission control devices.
3. Record AVO indications of emissions from the storage tanks, closed vent system to the control devices and control devices.
4. Using the OGI camera, survey each process in infrared modes (auto, manual, and/or high-sensitivity modes). Record any uncontrolled emissions with the OGI camera and describe the frequency and magnitude of emissions in the field notebook.
5. Observe control devices (enclosed combustor or utility flare) for visible emissions. If there is visible emissions present, conduct Method 22 and record the observations.
6. Using another OGI camera, if available, confirm any observations of uncontrolled emissions with another inspector.
7. If there are operators present onsite, share any Areas of Concern.
Table 1 lists general inspection and well pad details for each inspected well pad. The well pad information located in Table 1 is from the North Dakota Industrial Commission (NDIC) well index located online at https://www.dmr.nd.gov/oilgas/.
Table 1: Inspection and Facility Details of Facilities Inspected
Date 10/23/2024
Arrival Time 10:26
Departure Time 10:35
Well Pad Name Bullet Pad 510E
10/23/2024 11:04 10/23/2024 11:08
11:07 11:17
10/23/2024 11:20 10/23/2024 11:24
11:23 11:35
Indy Infill Pad 15-32B MHA 3-3229H-150-91
MHA 2-3229H-150-91 MHA 6-06-01H-149-92
API Number 3302502124 3302502125 3302502126 3302502127 3302502128 3302502129 3302502130 3302502131 3302502132 3302502133 3302502134 3302502135 3302502786 3302502787 3302501318 3302501319 3302501320 3302501321 3302501562 3302501563 3302502704 3302502705 3302502706 3302502707
Latitude 47.739839
47.7619937 47.7610854 47.7603919 47.7590195
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Longitude -102.320987
-102.347645 -102.344328 -102.356042 -102.359782
10/23/2024 11:37 11:59
10/23/2024 12:02 10/23/2024 14:25
12:18 14:35
10/23/2024 14:47 15:03 10/23/2024 15:04 15:08 10/23/2024 15:17 15:38
10/24/2024 9:06
9:14
10/24/2024 10:27 10:34
Independence 16-31B
MHA 1-0601H-149-92 Skunk Creek Pad 13-3D
Bullwinkle Pad 15-4D Rocky Pad 6-90 Buffalo Pad 1006D
Vegas 1-1-36th
Tipi V 16-13X Tier 1
3302501467 3302501468 3302501469 3302501470 3302501471 3302501472 3302501473 3302501474 3302501475 3302501476 3302501037 3302501038
3302501801 3302501802 3302501803 3302501804 3302501805 3302501806 3302501807 3302501808 3302501809 3302501810 3302501946 3302501947 3302501948 3302501949 3302501990 3302501991 3302501992 3302501993 3302501750 3302501751 3302501752 3302501753 3302501754 3302501755 3302501756 3302501757 3302501758 3302501759 3305307795 3305308229 3305308230 3305308231 3305308232 3305308268 3305308269
3305306683 3305306684
47.7622
47.7474564 47.748104
47.7463545 47.7428069 47.7495653
47.7445846 47.805122
-102.36539
-102.366664 -102.44730
-102.45382 -102.459872 -102.497995
-102.775169 -102.77293
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3305306685 3305306686 3305307496 3305307497 3305307498 3305307499 3305307863
Observations and Regulatory Applicability Fort Berthold FIP and NSPS OOOOa regulations which are potentially relevant to the Areas of Concern observed during inspections are summarized in this section.
Tables 2 and 3 at the end of this report summarize inspection observations and findings. Table 2 summarizes storage tank observations. Table 3 includes details of control devices and related observations. See Appendix A for a log of images and videos taken during the inspections.
Fort Berthold FIP Applicability Based on drilling information reported to the NDIC well index by Oasis (Chord), the facilities listed in Table 1 were completed after the August 12, 2007, applicability date (per 40 C.F.R. 49.4161) and are producing from the Bakken Pool (per 40 C.F.R 49.4163(a)(1)) and are thus subject to the Fort Berthold FIP.
Closed Vent System Equipment Requirements [ 49.4165(b)] Per 49.4165(b)(1), "Each closed-vent system must route all produced natural gas and natural gas emissions from production and storage operations to the natural gas sales pipeline or the control devices...". The EPA, using an OGI camera, detected natural gas emissions from production and storage tanks at Independence 16-31B. See Area of Concern #1 above.
Utility Flare Requirements [ 49.4165(c)] Per 49.4165(c)(1), "For each enclosed combustor or utility flare, the owner or operator must follow the manufacturer's written operating instructions, procedures and maintenance schedule to ensure good air pollution control practices for minimizing emissions." The EPA noted UBHC emissions indicating poor air pollution control practices from a lit flare at the Bullwinkle Pad 15-4D well pad. See Area of Concern #2 above.
Per 49.4165(c)(6)(vii), "The owner or operator must ensure that each enclosed combustor and utility flare is operated with no visible smoke emissions." Per 49.4166(g)(3) and EPA Reference Method 22, the EPA noted black smoke emissions at the MHA 3-32-29H-150-91, MHA 6-06-01-H-149-92, Independence 16-31B, MHA 1-06-01H-149-92, Skunk Creek Pad 13-3D, Bullwinkle Pad 15-4D, and Buffalo Pad 10-06D well pads. See Area of Concern #3 above.
NSPS OOOO Applicability Based on well production information reported by Oasis to the NDIC and the date of construction, reconstruction, or modification of the storage vessels, the EPA believes that
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storage vessels and associated emissions control equipment at the MHA 6-06-01-H-149-92, Independence 16-31B, Skunk Creek Pad 13-3D, Bullwinkle Pad 15-4D, and Buffalo Pad 10-06D well pads are potentially subject to requirements for storage vessel affected facilities in NSPS OOOO.
Closed Vent System Equipment Requirements [ 60.5411(c)(1)] Per 60.5411(c)(1), owners and operators must "design the closed vent system to route all gases, vapors, and fumes emitted from the material in the storage vessel to a control device that meets the requirements specified in 60.5412(c) and (d), or to a process." The EPA, using an OGI camera, observed emissions from the closed vent system at the Independence 16-31B well pad. See Area of Concern #1 above.
Control Device Requirements [ 60.5412(d) and 60.5417(h)] Per 60.5417(h)(3), "Each control device must be operated following the manufacturer's written operating instructions, procedures and maintenance schedule to ensure good air pollution control practices for minimizing emissions." The EPA noted UBHC emissions indicating poor air pollution control practices from a lit flare at the Bullwinkle Pad 15-4D well pad. See Area of Concern #2 above.
Per 60.5412(d)(1)(iii), owners and operators must, "Operate the combustion control device with no visible emissions, except for periods not to exceed a total of 1 minute during any 15-minute period." The EPA observed black smoke continuously for more than five minutes (per Method 22) at the MHA 6-06-01-H-149-92, Independence 16-31B, Skunk Creek Pad 13-3D, Bullwinkle Pad 15-4D, and Buffalo Pad 10-06D well pads. See Area of Concern #3 above.
NSPS OOOOa Applicability Based on Oasis' NSPS OOOOa annual reporting, the EPA believes that storage vessels and associated emissions control equipment at the MHA 1-06-01H-149-92 well pad are potentially subject to requirements for storage vessel affected facilities in NSPS OOOOa.
Control Device Requirements [ 60.5412a(d)] Per 60.5412a(d)(1)(iii), owners and operators must, "Operate the combustion control device with no visible emissions, except for periods not to exceed a total of 1 minute during any 15-minute period." The EPA observed black smoke continuously for more than five minutes (per Method 22) at the MHA 1-06-01H-149-92 well pad. See Area of Concern #3 above.
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Table 2: Inspection Details: Storage Tank Observations
Well Pad Name
Number of
AVO (Audio, visual,
Storage Tanks
olfactory) Observations
Independence 16-31B 14
None
Emissions Description
Continuous small plume of emissions from the thief hatch.
Media File Name
MOV_3541.mp4 MOV_3542.mp4
Table 3: Inspection Details: Control Devices and AVO/OGI Observations
Well Name
Number of Control Device
Control Device Type
Visible Pilot Flame (Y/N)
Active Flaring (Y/N)
Method 22 Observations
Emission Description
MHA 332-29H150-91
2 High Pressure Y Y 1 Low Pressure Y Y
Continuous smoking
from High Pressure
Fail
flare located in the
middle. Method 22
was performed.
N
MHA 6-
1 Low Pressure Y Y
06-01-H-
149-92
1 High Pressure Y Y
Continuous smoking
from Low Pressure
Fail
flare. Method 22 was
performed.
N
Independe nce 16-
1 Low
Y
Y
31B Pressure
Continuous smoking
from Low Pressure
Fail
flare. Method 22 was
performed.
Media File Name None None None
Slope to K/O Drum
Notes
Downward
Downward Downward
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MHA 106-01H149-92
1 High Pressure Y Y
2-prong
1 High
Y
N
Pressure
1 High-low Y
Y
Skunk Creek Pad 13-3D
1 High- Low
Y
Y
2-prong
1 High
Y
N
Pressure
Bullwinkle
Pad 15-4D
1 Low Pressure Y Y
Buffalo Pad 1006D
2-prong
1 High
Y
Y
Pressure
1 High- Low
Y
Y
N N Failed Fail N Fail
Continuous smoking from High-low flare. Method 22 was performed.
None
Continuous smoking from High-Low flare. Method 22 performed.
None
Downward
MOV_3543. Continuous emissions from top of the fuel control valve.
Downward
UBHC emissions from a High Pressure flare with a lit pilot light that was not actively flaring. Continuous smoking from Low Pressure flare. Method 22 performed.
MOV_3548.mp4 MOV_3549.mp4
None
Downward
N
Continuous smoking None
Fail
of High-Low flare.
Method 22 performed.
Downward
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APPENDIX A: Photograph and Video Log
Media File
Description
Well Pad Name
MOV_3541.mp4* MOV_3542.mp4*
Continuous small plume of emissions from the thief hatch.
Independence 16-31B
MOV_3543.mp4*
Continuous emissions from top of the fuel control valve.
MHA 1-06-01H-149-92
MOV_3548.mp4* MOV_3549.mp4*
UBHC emissions from a High Pressure flare with a lit pilot light that was not actively flaring.
Bullwinkle Pad 15-4D
entrysign-20241023-103324.jpg Entry Sign
Bullet Pad 5-10E
entrysign-20241023-160734.jpg Entry Sign
Indy Infill Pad
entrysign-20241023-160823.jpg Entry Sign
MHA 3-32-29H-150-91
entrysign-20241023-162016.jpg Entry Sign
MHA 2-32-29H-150-91
entrysign-20241023-162452.jpg Entry Sign
MHA 6-06-01H-149-92
entrysign-20241023-163709.jpg Entry Sign
Independence 16-31B
entrysign-20241023-170252.jpg Entry Sign
MHA 1-06-01H-149-92
entrysign-20241023-192602.jpg Entry Sign
Skunk creek pad 13-D
entrysign-20241023-200527.jpg Entry Sign
Bullwinkle Pad 15-4D
entrysign-20241023-200527.jpg Entry Sign
Rocky Pad 6-9D
entrysign-20241023-201739.jpg Entry Sign
Buffalo Pad 10-06D
entrysign-20241024-140717.jpg Entry Sign
Vegas 1-12Y pad
entrysign-20241024-153219.jpg Entry Sign
TIPI V 16-13X Tier 1
*In addition to recording metadata through the OGI camera's system, EPA collected metadata for the media files recorded
during the inspections, including the date, time, and location of the recorded media, in the Survey123 ArcGIS application at
the time of the inspections. Due to a technical issue experienced with the OGI camera's metadata captured for the .mp4type files, the Survey123 metadata was used as the primary reference for verifying inspection media file data.
Appendix A Page 1 of 1