PM2.5 24-hour 98th percentile
PM2.5 24-hour 98th percentile in McKenzie County reached 36.0 µg/m³ in 2024, 3% above the EPA NAAQS of 35 µg/m³.
10 top TRI facilities tracked here. PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) fell meaningfully year over year (-26%). PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) concentrations have fallen 46% since 2011.
FIPS 38053 · population 14,081
PM2.5 24-hour 98th percentile in McKenzie County reached 36.0 µg/m³ in 2024, 3% above the EPA NAAQS of 35 µg/m³.
Each red dot is one of the top TRI facilities. Size reflects 2024 total releases. County boundary outlined in blue.
PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) concentrations have fallen 46% since 2011.
PM2.5 24-hour 98th percentile (NAAQS 35 µg/m³ (24-hour)) concentrations have more than doubled since 2011.
Ozone 8-hour 4th-highest daily max (NAAQS 0.070 ppm (8-hour)) concentrations are up 10% since 2011.
NO₂ annual mean (NAAQS 53 ppb (annual)) concentrations are up 15% since 2011.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
TRI air releases (5.1 fugitive + 5.2 stack) concentrations are up 29% since 2013.
TRI water releases (5.3) volumes here are too small to anchor a multi-year trend; YoY movement is still shown above.
TRI land + off-site releases concentrations have more than doubled since 2013.
Greenhouse gases (GHGRP large emitters, through 2023) concentrations have more than doubled since 2011.
| Facility | City | Top chemical | Total releases | YoY |
|---|---|---|---|---|
| Oneok Rockies Midstream LLC - Grasslands Gas PlantOneok INC | Alexander | Hydrogen sulfideHealth riskAcutely toxic at high concentrations (paralyzes the olfactory nerve, then respiratory failure); chronic low-level exposure causes eye and respiratory irritation. (NIOSH) | 12.2M lb | -6% |
| Demicks Lake Gas PlantOneok INC | Watford City | n-HexaneHealth riskPeripheral neurotoxin. Chronic exposure causes numbness and paralysis in the extremities. (ATSDR) | 38k lb | +46% |
| Little Missouri Gas PlantTarga Resources CORP | Watford City | n-HexaneHealth riskPeripheral neurotoxin. Chronic exposure causes numbness and paralysis in the extremities. (ATSDR) | 29k lb | +114% |
| Watford City PlantKinder Morgan | Alexander | n-HexaneHealth riskPeripheral neurotoxin. Chronic exposure causes numbness and paralysis in the extremities. (ATSDR) | 18k lb | +7% |
| Red Wing Creek II Gas PlantTrue Oil LLC | Arnegard | n-HexaneHealth riskPeripheral neurotoxin. Chronic exposure causes numbness and paralysis in the extremities. (ATSDR) | 8k lb | +4% |
| Wild Basin Gas Processing &Crude Handling FacilityEnergy Transfer LP | Watford City | n-HexaneHealth riskPeripheral neurotoxin. Chronic exposure causes numbness and paralysis in the extremities. (ATSDR) | 8k lb | -6% |
| Garden Creek Gas PlantOneok INC | Watford City | n-HexaneHealth riskPeripheral neurotoxin. Chronic exposure causes numbness and paralysis in the extremities. (ATSDR) | 6k lb | -81% |
| Lonesome Creek Gas PlantOneok INC | Alexander | n-HexaneHealth riskPeripheral neurotoxin. Chronic exposure causes numbness and paralysis in the extremities. (ATSDR) | 4k lb | -74% |
| Bear Den Gas PlantEnergy Transfer LP | Watford City | n-HexaneHealth riskPeripheral neurotoxin. Chronic exposure causes numbness and paralysis in the extremities. (ATSDR) | 3k lb | +95% |
| Roosevelt Gas PlantKinder Morgan | Watford City | MethanolHealth riskAcutely toxic if ingested or inhaled. Metabolizes to formaldehyde and formic acid, causing blindness and metabolic acidosis. (EPA) | 2k lb | -45% |
All block groups in McKenzie County County, ND: 14,081 residents. County disparity score for pm2.5 (fine particulate) sits well below the reference (0). Why we surface this →
Low-income
People of color
Under age 5
Over age 64
| Indicator | Disparity score | Reading |
|---|---|---|
| PM2.5 (fine particulate) | 0 | well below the reference |
| Ozone | 55 | below the reference |
| Nitrogen dioxide (NO₂) | 31 | well below the reference |
| Diesel particulate | 2 | well below the reference |
| Toxic releases (RSEI) | 6 | well below the reference |
| Traffic proximity | 9 | well below the reference |
| Lead-paint risk (pre-1960 housing) | 45 | well below the reference |
| Superfund site proximity | 0 | well below the reference |
| RMP-facility proximity | 70 | below the reference |
| Hazardous-waste site proximity | 10 | well below the reference |
| Underground storage tanks | 34 | well below the reference |
| NPDES wastewater proximity | 42 | well below the reference |
| Drinking-water non-compliance | 0 | well below the reference |
Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror).
Modeled adult-prevalence estimates published by CDC PLACES, paired with this county's pollution and demographic context. Comparisons are ecological, not causal — pollution and disease prevalence covary at the area level, but the data does not attribute any individual's diagnosis to local exposure. How this section works →
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
PLACES uses BRFSS-modeled small-area estimates, not individual records. Crude prevalence shown above is the local rate as published; comparators are age-adjusted vs the North Dakota mean and the US mean — both population-weighted across counties — so geographies with different age structures stay apples-to-apples. Sources: CDC PLACES · 2025 release · BRFSS 2022-2023.
Pollution trends and TRI 2024 pages for every tracked city in this county. Alphabetical.
Sources.
All sources are federal public-domain datasets under 17 USC §105. We aggregate but do not relabel; the underlying observations remain attributable to EPA.