EPA TRI Facility · Petroleum

Marathon Mandan Refinery

Mandan, ND · Parent: Marathon Petroleum Corp

Total releases
1.9M lbs
Chemicals reported
40
Carcinogens
12
Primary pathway
Air Releases
Verify at EPA TRI →

Marathon Mandan Refinery has reported 1.9M lbs of toxic releases across 40 chemicals to the EPA Toxic Release Inventory, based on annual facility disclosures from 2019 through 2023. Of the chemicals reported, 12 are classified as carcinogens, representing 30% of the facility's chemical profile. The facility operates in the Petroleum sector. The primary release pathway is air releases, accounting for 97% of total releases. All release data shown below is self-reported to the EPA under the Emergency Planning and Community Right-to-Know Act (EPCRA) Section 313.

#881 of 25,902 TRI facilities nationwide by total reported releases - among the top 3.4% of reporting sites by volume. Ranking reflects reported pounds, not toxicity or health risk.

Marathon Mandan Refinery files annual Form R disclosures to the EPA Toxics Release Inventory under EPCRA Section 313, classified under NAICS 324110 (Petroleum). Across 5 years of records spanning 2019–2023, the site has disclosed 1.9M lbs in cumulative toxic releases across 40 distinct chemicals, 12 of which (30%) carry a carcinogenic classification.

The dominant release pathway is air releases at 1.8M lbs (97.0% of total volume), followed by off-site transfers at 1.7%. Between 2019 and 2023, reported totals increased by 7% - from 352.9K lbs to 377.8K lbs. The facility is operated under parent company Marathon Petroleum Corp.

TRI Form R values are self-reported estimates, not measured stack emissions, and treat every pound of reported chemical equally regardless of toxicity. Inclusion in the TRI database does not establish a health risk to nearby residents; it documents the annual reporting record that Marathon Mandan Refinery has filed with the EPA under federal community right-to-know requirements.

Quick Facts

Industry
Petroleum
NAICS Code
324110
Total Releases
1.9M lbs
Chemicals Reported
40
Latest Report Year
2023

Compare this facility

See how Marathon Mandan Refinery stacks up against nearby facilities and the typical reporter.

Total reported releases
Marathon Mandan Refinery
1.9M lbs
Basin Electric Antelope Valley Station
167.8M lbs

99% less than the comparison

Chemicals reported
Marathon Mandan Refinery
40
Basin Electric Antelope Valley Station
55

27% less 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 Marathon Mandan Refinery releases toxic chemicals into the environment. Total: 1.9M lbs.

Air Releases 1.8M lbs (97.0%)
Off-site Transfers 31.8K lbs (1.7%)
Water Discharges 15.4K lbs (0.8%)
Land Disposal 9.0K lbs (0.5%)
View 5-Year Emissions Trend →

Emissions Trend Summary

From 2019 to 2023, total releases increased by 7% (352.9K lbs to 377.8K lbs).

Reported total releases by year

Marathon Mandan Refinery - annual TRI totals

million lbs

What this shows Year-over-year reported totals. TRI figures are self-reported estimates and can swing with production levels, waste-rock handling and reporting changes, not only with emissions controls.

Source EPA Toxics Release Inventory (TRI)
Year Total Chemicals
2019 352.9K lbs 36
2020 359.7K lbs 38
2021 381.7K lbs 36
2022 424.1K lbs 38
2023 377.8K lbs 39

Chemical Releases

Aggregated across all reporting years (2019–2023). 12 of 40 chemicals are carcinogens. Sorted by total release volume.

Chemical Total Flags
Sulfuric acid (acid aerosols including mists, vapors, gas, fog, and other airborne forms of any particle size) 814.3K lbs -
Propylene 284.0K lbs -
Xylene (mixed isomers) 103.1K lbs -
Toluene 96.4K lbs -
n-Hexane 69.2K lbs -
Methanol 68.3K lbs -
Ethylene 65.3K lbs -
Phenol 53.6K lbs -
Ammonia 38.9K lbs -
Cresol (mixed isomers) 36.9K lbs -
1,2,4-Trimethylbenzene 32.6K lbs -
Cyclohexane 30.4K lbs -
Hydrogen cyanide 28.2K lbs -
Carbonyl sulfide 24.6K lbs -
Lead And Lead Compounds 20.8K lbs -
Ethylbenzene 19.9K lbs Carcinogen
Benzene 17.5K lbs Carcinogen
Hydrochloric acid (acid aerosols including mists, vapors, gas, fog, and other airborne forms of any particle size) 17.0K lbs -
Nickel 13.9K lbs Carcinogen
Carbon disulfide 10.1K lbs -
Hydrogen sulfide 9.5K lbs -
Hydrogen fluoride 8.6K lbs -
Manganese 7.6K lbs -
Zinc compounds 5.8K lbs -
Certain glycol ethers 5.6K lbs -
Naphthalene 3.2K lbs Carcinogen
Tetrachloroethylene 3.1K lbs Carcinogen
Cumene 2.4K lbs Carcinogen
Nickel And Nickel Compounds 1.5K lbs Carcinogen
Polycyclic aromatic compounds 689 lbs Carcinogen
Phenanthrene 624 lbs -
Anthracene 616 lbs -
1,3-Butadiene 598 lbs Carcinogen
Chromium 490 lbs -
Cobalt compounds 276 lbs Carcinogen
Biphenyl 158 lbs -
Mercury And Mercury Compounds 41 lbs -
Benzo[g,h,i]perylene 36 lbs -
Molybdenum trioxide 34 lbs Carcinogen
Dioxin and dioxin-like compounds 0 lbs Carcinogen

Location

Coordinates
46.8432, -100.8916
ZIP Code
58554
EPA Facility ID
58554MCLCMNORTH

About TRI Data

Data as of 2023 reporting year. Source: U.S. Environmental Protection Agency (EPA) Toxic Release Inventory.

Data comes from the EPA Toxic Release Inventory (TRI) program. Facilities that manufacture, process, or otherwise use listed toxic chemicals above threshold amounts are required to report annually to the EPA.

Release quantities are self-reported by the facility and may represent estimates rather than exact measurements. "Total releases" includes releases to air, water, land, and off-site transfers for disposal. Quantities shown here are aggregated across all available reporting years.

PlainEnviro presents this data without advocacy framing. The presence of a facility in the TRI database does not by itself indicate a health risk. For site-specific health questions, consult your local environmental or health agency.

Frequently Asked Questions

What chemicals does Marathon Mandan Refinery release?
Marathon Mandan Refinery has reported releases of 40 chemicals to the EPA Toxic Release Inventory, totaling 1.9M lbs. 12 of these (30%) are classified as carcinogens.
What industry is Marathon Mandan Refinery in?
Marathon Mandan Refinery is classified under the "Petroleum" industry (NAICS code 324110), located in Mandan, ND.
How long has Marathon Mandan Refinery reported to the TRI?
Marathon Mandan Refinery has EPA Toxic Release Inventory data spanning 5 years, from 2019 to 2023.
How does Marathon Mandan Refinery release toxic chemicals?
The primary release pathway for Marathon Mandan Refinery is air releases, accounting for 97.0% of total releases (1.8M lbs). Secondary pathway: off-site transfers (1.7%).
Are emissions from Marathon Mandan Refinery increasing or decreasing?
From 2019 to 2023, total releases increased by 7%, from 352.9K lbs to 377.8K lbs.
Is Marathon Mandan Refinery a health risk?
The presence of a facility in the TRI database does not by itself indicate a health risk. Release quantities are self-reported estimates. For site-specific health questions, consult your local environmental or health agency.
Does Marathon Mandan Refinery release carcinogens?
Yes, Marathon Mandan Refinery reports 12 chemicals classified as carcinogens, representing 30% of all chemicals reported by this facility. Carcinogen classification is based on EPA and IARC assessments.

What to do with this facility's data

Use this facility profile as a starting point, then check how it compares.

  • See whether releases reported by Marathon Mandan Refinery are rising or falling over time. View trends
  • This facility ranks #881 of 25,902 TRI facilities nationwide by total reported releases - among the top 3.4% of reporting sites by volume. Ranking reflects reported pounds, not toxicity or health risk. See the full rankings
  • Check North Dakota's statewide profile for the full picture: total facilities, water systems, and Superfund sites. View North Dakota profile

TRI release totals are self-reported estimates submitted to the EPA, not independently measured stack emissions; a high rank reflects reported volume, not necessarily local health risk.

Related

Sources & how this page was built

Every figure on this page traces to public, federal-government data on Marathon Mandan Refinery. The records below are the primary sources; our methodology explains how they are joined, computed, and verified.

Retrieved and formatted by PlainEnviro Editorial. TRI release totals are self-reported estimates, not measured stack emissions.

According to the U.S. Environmental Protection Agency, the Toxics Release Inventory has required annual industrial disclosure since its creation under the Emergency Planning and Community Right-to-Know Act in October 1986, and this facility's record is drawn from PlainEnviro's database of more than 25,000 EPA-tracked facilities through the 2023 reporting year; see our methodology for full source citations and refresh cadence.