EPA TRI Facility · Natural Gas Processing
Oneok Rockies Midstream LLC - Grasslands Gas Plant
Alexander, ND · Parent: Oneok Inc
- Total releases
- 26.9M lbs
- Chemicals reported
- 8
- Carcinogens
- 2
- Primary pathway
- Land Disposal
LAND Form-R mix
Oneok Rockies Midstream LLC - Grasslands Gas Plant: how the 26.9M lbs splits
26.9M lbs across all reported pathways
- Land Disposal 26.8M lbs 99.7%
- Off-site Transfers 58.8K lbs 0.2%
- Air Releases 24.7K lbs 0.1%
Oneok Rockies Midstream LLC - Grasslands Gas Plant's 26.9M lbs Form-R total is LAND - land disposal is 99.7% of the bar. Next segment: off-site transfers at 0.2%. Leading chemical by pounds: Hydrogen sulfide.
Carcinogen-classified pounds vs other reported pounds
Same cumulative TRI total as above, split by EPA/IARC carcinogen classification on each chemical: pounds share, not chemical count. Classification is not a site health-risk score.
HEAVY volume LAND pathway TRACE-CARC
Oneok Rockies Midstream LLC - Grasslands Gas Plant is an EPA Toxics Release Inventory reporter in Alexander, ND, in the natural gas processing sector. It reported 13.0M lbs of releases across 7 chemicals in 2023, and 26.9M lbs in total across its 2022-2023 reporting years. That ranks 72 of 25,986 TRI facilities nationwide by cumulative reported pounds, counting each facility over however many years it has filed. In North Dakota's 94 reporting TRI sites, Basin Electric Antelope Valley Station leads both reported pounds (167.8M lbs) and chemical count (55 chemicals). The two rankings do not invert in this pool. Reported volume fell against 2022. Pounds reported are not a measure of toxicity or health risk. Nearest other TRI reporters: Lonesome Creek Gas Plant; Watford City Plant; Demicks Lake Gas Plant; Red Wing Creek II Gas Plant. Similar-scale Natural Gas Processing peers outside North Dakota: Jal 3 Gas Plant; Dagger Draw Gas Plant; Eunice Gas Plant; Midway Gas Plant. Other Oneok Inc sites in this extract: Oneok Hydrocarbon LP - Bushton Complex; Canadian Valley Gas Plant; Magellan Processing L.P.; Oneok Field Svc/maysville Gas Plt. Largest disclosed chemicals by pounds: Hydrogen sulfide; n-Hexane; Diethanolamine; Cyclohexane.
Oneok Rockies Midstream LLC - Grasslands Gas Plant stamps HEAVY volume with a dominant LAND pathway (99.7% land disposal) across 8 chemicals · 2 carcinogen-classified. Cumulative Form-R extract: 26.9M lbs (2022–2023). All figures are self-reported EPCRA §313 estimates, not measured stack emissions or a health-risk score. Scale peers include Jal 3 Gas Plant and Dagger Draw Gas Plant.
Oneok Rockies Midstream LLC - Grasslands Gas Plant vs. every reporting TRI facility
Cumulative reported release pounds, with this facility marked in the national distribution
27M lbs Top 1% higher than 100% of 25,986 reporting TRI facilities
Each bar is a $1M-wide band; taller bars hold more reporting TRI facilities. The dashed line and filled bar mark this facility. Hover, focus, or tap a bar for its full count, share, and position.
Source U.S. Environmental Protection Agency, Toxics Release Inventory · 2023 reporting year
Oneok Rockies Midstream LLC - Grasslands Gas Plant inside Mckenzie's TRI pounds
Among the 339 Natural Gas Processing facilities in this database, Oneok Rockies Midstream LLC - Grasslands Gas Plant reports the 4th-largest volume, placing it in the top 1.2% of its sector. This one site accounts for 99.1% of every pound reported in Mckenzie. Its reported volume is concentrated rather than spread: Hydrogen sulfide alone is 99.7% of the total. Scale peers outside North Dakota include Jal 3 Gas Plant and Dagger Draw Gas Plant.
County-dominant here means ≥25% of Mckenzie's reported pounds (27.1M lbs county total). Shares only print when the site reports ≥1,000 lbs.
Annual disclosure change
What changed: EPA TRI 2023 reporting year
- Oneok Rockies Midstream LLC - Grasslands Gas Plant's total reported releases fell from 13.9 million lb in 2022 to 13.0 million lb in 2023, based on EPA TRI filings.
- Oneok Rockies Midstream LLC - Grasslands Gas Plant's off-site transfers rose from 10.7 thousand lb in 2022 to 48.1 thousand lb in 2023, based on EPA TRI filings.
- Oneok Rockies Midstream LLC - Grasslands Gas Plant's air releases rose from 10.7 thousand lb in 2022 to 14.0 thousand lb in 2023, based on EPA TRI filings.
- Oneok Rockies Midstream LLC - Grasslands Gas Plant's land releases fell from 13.9 million lb in 2022 to 12.9 million lb in 2023, based on EPA TRI filings.
Oneok Rockies Midstream LLC - Grasslands Gas Plant Form-R facts
Compare this facility
See how Oneok Rockies Midstream LLC - Grasslands Gas Plant stacks up against nearby facilities and the typical reporter.
957.1× more than the comparison
4.0× more than the comparison
Comparison reflects reported pounds and chemical counts, not toxicity or health risk. Averages cover facilities reporting any release.
How does this facility release toxic chemicals?
How Oneok Rockies Midstream LLC - Grasslands Gas Plant releases toxic chemicals into the environment. Total: 26.9M lbs.
Emissions Trend Summary
From 2022 to 2023, total releases decreased by 7% (13.9M lbs to 13.0M lbs).
Oneok Rockies Midstream LLC - Grasslands Gas Plant: annual Form-R pounds
HEAVY site · LAND pathway · TRI years 2022–2023
- 2022
- 2023
What this shows Oneok Rockies Midstream LLC - Grasslands Gas Plant year-over-year reported totals (decreased by 7% from 2022 to 2023). TRI figures are self-reported estimates and can swing with production, waste handling, and reporting changes, not only with controls. Lead chemical in the extract: Hydrogen sulfide.
| Year | Total | Chemicals |
|---|---|---|
| 2022 | 13.9M lbs | 7 |
| 2023 | 13.0M lbs | 7 |
Chemical Releases
Aggregated across all reporting years (2022–2023). 2 of 8 chemicals are carcinogens. Sorted by total release volume.
| Chemical | Total | Flags |
|---|---|---|
| Hydrogen sulfide | 26.8M lbs | - |
| n-Hexane | 37.6K lbs | - |
| Diethanolamine | 28.5K lbs | - |
| Cyclohexane | 8.2K lbs | - |
| Toluene | 5.8K lbs | - |
| Benzene | 3.2K lbs | Carcinogen |
| Ethylbenzene | 326 lbs | Carcinogen |
| Methanol | 136 lbs | - |
Oneok Rockies Midstream LLC - Grasslands Gas Plant · LAND-pathway site
Nearest TRI Facilities to Oneok Rockies Midstream LLC - Grasslands Gas Plant
Closest other reporters in North Dakota - including Lonesome Creek Gas Plant, Watford City Plant, Demicks Lake Gas Plant, ordered by distance.
Showing 8 of 93 other reporting facilities in North Dakota.
Similar Natural Gas Processing Facilities
Other Natural Gas Processing facilities with similar total release volumes (±80%), outside North Dakota - e.g. Jal 3 Gas Plant, Dagger Draw Gas Plant, Eunice Gas Plant.
Compare beyond North Dakota
Nationwide peers by reported pounds & chemical count
Cross-state TRI reporters nearest Oneok Rockies Midstream LLC - Grasslands Gas Plant on cumulative reported pounds (26.9M lbs) and distinct chemical count (8). Release-pound peers include Wieland Metals Inc, Dyno Nobel Inc-Cheyenne Plant, Ineos Pigments USA Inc. Chemical-count peers include Prepa-South Coast Power Plant, Argos Puerto Rico Corp., US Tsubaki Automotive LLC. Neighborhoods are forced disjoint so each axis surfaces a different set of sites.
Similar reported release pounds
Nearest out-of-state reporters (≥1,000 lbs) by absolute TRI pounds, not same-industry or same-county neighbors.
Similar chemical count
Nearest out-of-state reporters by distinct Form-R chemicals (deduped against the release-pound neighborhood).
Other Oneok Inc Facilities
Same-parent TRI sites ranked by reported releases - including Oneok Hydrocarbon LP - Bushton Complex, Canadian Valley Gas Plant, Magellan Processing L.P..
About TRI Data
Data as of 2023 reporting year. Source: U.S. Environmental Protection Agency (EPA) Toxic Release Inventory.
On this page the largest disclosed chemicals include Hydrogen sulfide, n-Hexane, Diethanolamine, Cyclohexane; nearby reporters include Lonesome Creek Gas Plant. Oneok Rockies Midstream LLC - Grasslands Gas Plant stamps HEAVY volume · LAND pathway · TRACE-CARC carcinogen-lbs on this Form-R extract. Totals are self-reported estimates under EPCRA §313, not measured stack emissions or a health-risk score.
Use and verify this record
This Oneok Rockies Midstream LLC - Grasslands Gas Plant TRI extract (HEAVY · LAND · TRACE-CARC · lead Hydrogen sulfide) joins EPA Form-R filings with facility identity - reported pounds, not a health-risk rating.
Oneok Rockies Midstream LLC - Grasslands Gas Plant totals are self-reported EPCRA §313 estimates for Alexander, ND, latest year 2023. Form-R rows span 2022–2023 (2 years). NAICS 211130 · Natural Gas Processing. 99.1% of Mckenzie TRI pounds in this extract. Nearest ABS peer: Wieland Metals Inc (Δ 195.1K lbs). Pounds ≠ exposure.
Oneok Rockies Midstream LLC - Grasslands Gas Plant stamps HEAVY volume · LAND pathway · TRACE-CARC · lead Hydrogen sulfide. PlainEnviro renders this EPA Form-R extract from its pipeline; no figure is typed in by an editor. Corrections: editorial policy.
All federal data sources used on this page
- EPA Toxics Release Inventory (TRI) Basic Data Files - annual self-reported chemical-release filings. epa.gov
- EPA TRI Program reference - how chemicals and reported releases are counted. epa.gov
- EPA Facility Registry Service - facility location and identity. epa.gov
- EPA ECHO - regulatory and compliance context. epa.gov
- EPA Envirofacts - the EPA data warehouse exposing these datasets. epa.gov