Inspectors reported hydrocarbon emissions escaping from storage tanks and flares at EOG Resources sites. The resulting agreement requires a civil penalty, two years of monitoring and a separate $2 million engine project.
Document investigationTL;DR
- During inspections in 2023 and 2024, the Environmental Protection Agency said it detected hydrocarbons escaping from tank openings at five listed well-pad groupings and from flares with unlit pilot lights at seven locations.
- EPA also reported visible emissions from three operating utility flares and alleged extensive testing, monitoring, inspection, recordkeeping and reporting failures at EOG’s Clarks Creek facility.
- The facilities at the center of the North Dakota inspections were within the Fort Berthold Indian Reservation, where a federal plan regulates oil-and-gas emissions to protect tribal air resources.
- EOG agreed to pay a $333,087 civil penalty, install continuous pilot-light monitors and flare-flow meters, conduct monthly emissions checks and attempt initial repairs within 24 hours.
- A separate supplemental environmental project requires at least $2 million to convert eight drilling-rig engines for dual-fuel operation over at least 96,000 cumulative hours.
- EOG neither admitted nor denied the agreement’s factual allegations. The settlement was entered without adjudication of the disputed facts or law.
The agreement converts a set of field observations and missing compliance records into a two-year test of whether EOG can keep its pollution-control equipment operating—and document that it does.
Transparency notice: This article relies on the 41-page consent agreement filed with EPA Region 8 on August 5, 2026. The document contains EPA allegations, inspection descriptions, settlement obligations and statements certified by EOG. EOG neither admitted nor denied the factual allegations and the parties settled without adjudication. The agreement says it becomes effective upon execution and filing of a final order; the supplied document does not contain a separate final-order text, so this article does not independently establish the effective date.
The Facts
At seven EOG Resources locations inspected in November 2023 and February 2024, EPA said hydrocarbons were escaping from flares whose pilot lights were out. At five listed well-pad groupings, inspectors reported hydrocarbon emissions from storage-tank thief hatches and vacuum breaks. Three operating utility flares produced visible emissions.
A thief hatch is an access lid on a storage tank. The hatch and related openings are supposed to remain sealed during normal operation so vapors move through a closed vent to a recovery system or combustion device. A flare’s pilot light performs the final part of that chain: when gas reaches the flare, the flame must be present to burn it. An unlit pilot can leave the control device unable to perform that function.
The observations formed only part of EPA’s case. At the Clarks Creek Central Facility, the agency alleged that EOG had not completed required inspections, performance testing, continuous monitoring, recordkeeping or reporting for a dehydration unit and six large stationary engines. Some dehydration-unit reporting and recordkeeping allegations reached back to August 2018.
| EPA inspection description | Listed locations | Why the equipment mattered |
|---|---|---|
| Hydrocarbons from tank thief hatches and vacuum breaks | Five well or pad groupings | Tank openings and closed vents are intended to contain vapors and route them to a recovery or control device. |
| Hydrocarbons from flares with unlit pilot lights | Seven wells or compressor sites | A flare must have a flame when emissions are routed to it if it is to function as a combustion control. |
| Visible emissions from operating utility flares | Three well-pad locations | The Fort Berthold rules require covered flares and enclosed combustors to operate without visible smoke emissions. |
How the Control Chain Was Supposed to Work
The applicable rules vary by equipment and facility, but the practical system is straightforward. Vapors from storage vessels should remain contained, move through sealed piping and reach a properly operating recovery or combustion device. Inspections, sensors and records are how the operator demonstrates that the chain continues to work between government visits.
EPA’s allegations touched each part of that chain. Inspectors reported emissions from tank openings and closed vents, unlit pilots and visible flare emissions. At Clarks Creek, the agency alleged that missing tests, monitors and records prevented EOG from demonstrating initial and continuing compliance for six reciprocating internal combustion engines—the large stationary engines identified in the agreement as RICE.
EPA said the addition of three engines in July 2019 raised Clarks Creek’s potential emissions of hazardous air pollutants above 25 tons per year, making it a major source under the relevant federal program. That threshold refers to potential emissions, not a finding that the facility actually released 25 tons in a year.
Inspection, Notice, Settlement
EPA alleged missing periodic reports and inspection or repair records for the Clarks Creek dehydration unit.
EOG installed three additional engines at Clarks Creek. EPA alleged the facility became a major source and that requirements applying at startup were not met.
EPA inspected Clarks Creek and later alleged visible flare smoke and detectable natural-gas emissions from closed vents serving two storage vessels.
Additional inspections produced the tank-hatch, unlit-pilot and visible-emissions observations described in the agreement.
EPA issued a notice of violation to EOG and provided a copy to North Dakota. A series of discussions continued through October 2025.
The consent agreement was stamped as filed with the EPA Region 8 hearing clerk.
Who Had to Live With the Risk
EOG owns or operates oil-and-gas production facilities within the Fort Berthold Indian Reservation in North Dakota. The federal implementation plan governing those facilities was created to protect tribal air resources and maintain compliance with national ambient-air standards. It requires operators to minimize natural-gas leakage and route storage emissions to recovery systems or control equipment.
The agreement establishes that EPA inspectors reported hydrocarbons and visible emissions at specific equipment. It does not quantify the total mass released from the alleged violations, identify the composition of each detected plume, calculate off-site concentrations or document an illness or injury suffered by any resident or worker. Those limits matter: a failed control system is evidence of uncontrolled emissions, but the supplied record does not support assigning a measured health outcome to those emissions.
The monitoring failures carry a different consequence. When required tests and records are absent, regulators lack the routine evidence intended to show whether engines, vents and flares remained within their operating and emissions limits. EPA’s settlement responds by requiring more frequent observation, continuous pilot-light monitoring and repeated reporting rather than relying on occasional inspections alone.
The record documents equipment and compliance failures alleged by EPA. It does not calculate the total pollution released or establish a specific injury to nearby residents.
What EOG Agreed to Change
The settlement’s central remedy is a two-year monitoring and reporting system. It covers Clarks Creek, facilities named in the inspection findings and five additional Wyoming well-pad sites listed in the agreement.
| Requirement | Timing | Practical effect |
|---|---|---|
| Observe covered flares and combustors for visible smoke | Once each calendar month, with at least seven days between checks | Creates a recurring check instead of leaving flare performance to sporadic government inspections. |
| Use optical gas imaging on closed-vent systems | Monthly | Looks for otherwise difficult-to-see emissions from vents and storage-vessel controls. |
| Install digital pilot-light monitors | Within 60 days of the effective date | Continuously checks flare pilots and records a parameter at least every five minutes. |
| Install flare-flow meters | Within 60 days of the effective date | Measures gas flowing to in-service high- and low-pressure flares, with monthly totals reported to EPA. |
| Attempt repairs after detected emissions or other potential noncompliance | First attempt within 24 hours; second attempt within 15 days if needed | Links detection to a defined repair clock, subject to specified delay-of-repair conditions. |
| Submit testing, monitoring, deviations and repair information | Four semiannual reports covering two years | Gives EPA a continuing record of performance, repairs and unresolved deviations. |
EOG must also comply with the hazardous-air-pollutant engine standards that apply to three engines remaining within the agreement’s compliance program: ENG-1, ENG-2 and ENG-4. Engines removed from service are no longer subject to that provision.
The $2 Million Engine Project
Separate from the $333,087 penalty, EOG agreed to fund a supplemental environmental project that the agreement says was not otherwise required by federal, state, tribal or local law. The company must permanently convert eight CAT 3512 diesel engines into dual-fuel engines and install them on two drilling rigs operated by third-party contractors.
The engines must operate at EOG-owned drilling sites in North Dakota and Wyoming for at least 96,000 cumulative dual-fuel hours. EOG must spend no less than $2 million, complete the conversions and installation within five months of the effective date, and begin rig operation within seven months.
EPA describes the project as designed to reduce drilling emissions by approximately 120 tons of nitrogen oxides and seven tons of carbon monoxide. Those are projected reductions in the settlement, not completed results. EOG’s eventual completion report must estimate the actual reductions, document the fuel mix and operating locations, and show that the engines were permanently converted.
If EPA concludes that EOG failed to complete the project satisfactorily—including the minimum spending and operating-hour requirements—the agreement sets a stipulated penalty of $2.225 million. Separate daily penalties apply to missed project deadlines and late reports, although the United States retains discretion to reduce or waive stipulated penalties.
What the Agreement Decided—and What It Did Not
This was a negotiated administrative settlement, not a trial. EOG admitted EPA’s jurisdiction, consented to the penalty and conditions, waived its right to contest the alleged legal violations, and waived an appeal of the final order accompanying the agreement. It also acknowledged that the settlement constitutes an enforcement action for purposes of its compliance history.
At the same time, EOG neither admitted nor denied the factual allegations. The parties expressly entered the agreement without adjudication of any issue of law or fact. The settlement therefore imposes enforceable obligations without turning every EPA allegation into a litigated factual finding.
Legal receipts
“Respondent … neither admits nor denies the factual allegations stated in section VI of this Agreement.”
“Completion of the terms of this Agreement resolves only Respondent’s liability for federal civil penalties for the violations alleged in section VII of this Agreement.”
The second quotation narrows the settlement’s reach. It resolves federal civil-penalty liability for the listed allegations; it does not excuse future noncompliance, decide permit questions or limit EPA’s authority to respond to an imminent and substantial endangerment.
What to Watch
- EOG Resources Whether the company installs the pilot monitors and flare-flow meters within the agreement’s 60-day window and documents monthly inspections and repairs.
- EPA Region 8 The four semiannual reports, particularly any recurring unlit pilots, vent emissions, delayed repairs or root-cause findings.
- Engine project Whether eight engines are permanently converted within five months and begin operating within seven months.
- EPA review Whether the completion report verifies at least 96,000 operating hours, $2 million in spending and the project’s actual emissions reductions.
- Agreement termination EOG can seek termination only after paying the penalty and demonstrating two years of substantial and material compliance; EPA then has 90 days to confirm termination or identify outstanding items.
The final measure of this settlement will not be its projected reductions. It will be the monitoring record: whether pilots remain lit, detected leaks are repaired on schedule, and the engine project produces the documented reductions required for EPA to declare it complete.
The source document for this investigation is attached below.
