EPA TRI Facility · Electric Utilities
Mystic Station
Charlestown, MA · Parent: Constellation Energy Generation LLC
- Total releases
- 46.4K lbs
- Chemicals reported
- 4
- Carcinogens
- 2
- Primary pathway
- Air Releases
Mystic Station is an EPA Toxics Release Inventory reporter in Charlestown, MA, in the electric utilities sector. It reported 9.5K lbs of releases across 3 chemicals in 2021, and 46.4K lbs in total across its 2019-2021 reporting years. That ranks 6,283 of 25,986 TRI facilities nationwide by cumulative reported pounds, counting each facility over however many years it has filed. Pounds reported are not a measure of toxicity or health risk.
Mystic Station has reported 46.4K lbs of toxic releases across 4 chemicals to the EPA Toxic Release Inventory, based on annual facility disclosures from 2019 through 2023. Of the chemicals reported, 2 are classified as carcinogens, representing 50% of the facility's chemical profile. The facility operates in the Electric Utilities sector. The primary release pathway is air releases, accounting for 100% 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.
Where this facility sits in the TRI record
Among the 513 Electric Utilities facilities in this database, Mystic Station reports the 346th-largest volume (46.4K lbs). Its reported volume is concentrated rather than spread: Ammonia alone is more than 99.9% of the total.
Placement is computed from reported TRI pounds in this database. Thresholds are fixed across every facility page: concentrated ≥60% of volume in one chemical, county-dominant ≥25% of the county total, carcinogen-heavy ≥50% of pounds. Share-based statements are shown only for sites reporting at least 1,000 lbs, because a share of a very small total is not a meaningful signal. Reported pounds are self-reported estimates and do not measure toxicity or health risk.
Mystic Station files annual Form R disclosures to the EPA Toxics Release Inventory under EPCRA Section 313, classified under NAICS 221112 (Electric Utilities). Across 3 years of records spanning 2019–2021, the site has disclosed 46.4K lbs in cumulative toxic releases across 4 distinct chemicals, 2 of which (50%) carry a carcinogenic classification.
The dominant release pathway is air releases at 46.2K lbs (99.6% of total volume), followed by water discharges at 0.2%. Between 2019 and 2021, reported totals decreased by 54% - from 20.8K lbs to 9.5K lbs. The facility is operated under parent company Constellation Energy Generation LLC.
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 Mystic Station has filed with the EPA under federal community right-to-know requirements.
Quick Facts
Compare this facility
See how Mystic Station stacks up against nearby facilities and the typical reporter.
23201.2× more than the comparison
33% 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 Mystic Station releases toxic chemicals into the environment. Total: 46.4K lbs.
Emissions Trend Summary
From 2019 to 2021, total releases decreased by 54% (20.8K lbs to 9.5K lbs).
Reported total releases by year
Mystic Station - annual TRI totals
- 2019 0
2019
0 million lbs
- 2020 0
2020
0 million lbs
- 2021 0
2021
0 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.
| Year | Total | Chemicals |
|---|---|---|
| 2019 | 20.8K lbs | 4 |
| 2020 | 16.2K lbs | 3 |
| 2021 | 9.5K lbs | 3 |
Chemical Releases
Aggregated across all reporting years (2019–2021). 2 of 4 chemicals are carcinogens. Sorted by total release volume.
| Chemical | Total | Flags |
|---|---|---|
| Ammonia | 46.4K lbs | - |
| Polycyclic aromatic compounds | 32 lbs | Carcinogen |
| Benzo[g,h,i]perylene | 1 lbs | - |
| Naphthalene | 0 lbs | Carcinogen |
Location
Nearest TRI Facilities to Mystic Station
The closest other reporting facilities in Massachusetts, ordered by distance.
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
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Explore More Data for Massachusetts
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 Mystic Station are rising or falling over time. View trends
- This facility ranks #6,283 of 25,986 TRI facilities nationwide by total reported releases. Ranking reflects reported pounds, not toxicity or health risk. See the full rankings
- Check Massachusetts's statewide profile for the full picture: total facilities, water systems, and Superfund sites. View Massachusetts 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.
Read our methodology - how this data is sourced, computed, and verified.
Related
Sources & how this page was built
Every figure on this page traces to public, federal-government data on Mystic Station. The records below are the primary sources; our methodology explains how they are joined, computed, and verified.
- EPA Toxics Release Inventory (TRI) Basic Data Files - annual self-reported chemical-release filings. epa.gov
- EPA TRI Program, chemical & reporting reference - what each chemical is and how releases are counted. epa.gov
- EPA Facility Registry Service (FRS) - authoritative facility location and identity. epa.gov
- EPA Enforcement & Compliance History Online (ECHO) - regulatory and compliance context. echo.epa.gov
- EPA Envirofacts - the EPA data warehouse that exposes these datasets. enviro.epa.gov
Retrieved and formatted by PlainEnviro. 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.