St. Mary Parish, LA

Moderate Risk (54/100)

Transparent derived index from EPA TRI / SDWIS / Superfund extracts: not an official EPA rating. Fixed caps: facilities ≤25 pts (50+ = max), log10 releases ≤25 pts, Superfund ≤25 pts (5/site), health-violation systems ≤15 pts (3/system), high-chemical facilities ≤10 pts. Bands: High ≥60, Moderate ≥30. See methodology. This is a different measure than the EJ Screening score for this county, which ranks it by percentile against other tracked counties rather than against these fixed caps.

Environmental data for St. Mary Parish in Louisiana · Population: 48,455

TRI sites such as Cabot Corp Canal Plant; Bollinger Marine Fabricators LLC; Orion Engineered Carbons-Ivanhoe Carbon Black Plant; SDWIS systems such as WATER & SEWER COMMISSION 4 OF ST MARY; CITY OF PATTERSON WATER SYSTEM; CITY OF FRANKLIN WATER SUPPLY anchor St. Mary Parish, LA's EPA extract. Derived burden score 54/100 (Moderate Risk) uses fixed national caps on density, log release volume, Superfund count, and health-flagged systems - not an official EPA rating.

Health-flagged SDWIS rows in St. Mary Parish include WATER & SEWER COMMISSION 4 OF ST MARY; CITY OF PATTERSON WATER SYSTEM; CITY OF FRANKLIN WATER SUPPLY, while Cabot Corp Canal Plant leads reported TRI pounds among local Form R filers. No AQS county monitors report here.

Burden score 54/100 (Moderate Risk) is the only weighted composite on this page. The tables below list every TRI facility, SDWIS system, and Superfund site EPA has on record for St. Mary Parish -- not just the names called out above -- reproducing the disclosure history as filed, not a current-safety verdict. Extract current as of 2026-08-25.

Release-over-release change

What changed for St. Mary Parish, LA: EPA TRI 2023 reporting year

2022 → 2023

Same facilities, both years

+5.5%

12 facilities that filed in 2022 and 2023

Whole inventory

+5.5%

1.0 million lb → 1.1 million lb, every facility that filed

Between the two reporting years, 2 facilities filed for the first time and 1 stopped filing. Facilities entering or leaving the inventory are excluded from the same-facility comparison above.

  • St. Mary Parish, LA's total reported releases rose from 1.0 million lb in 2022 to 1.1 million lb in 2023, based on EPA TRI filings.
  • St. Mary Parish, LA's off-site transfers rose from 70.3 thousand lb in 2022 to 116.0 thousand lb in 2023, based on EPA TRI filings.
  • St. Mary Parish, LA's land releases fell from 817 lb in 2022 to 472 lb in 2023, based on EPA TRI filings.
  • St. Mary Parish, LA's water releases rose from 453 lb in 2022 to 551 lb in 2023, based on EPA TRI filings.
County population (Census ACS)
48,455
TRI Facilities
17
Water Systems
8
Superfund Sites
0
Total Releases
4.6M lbs

Water Systems (8)

System System pop (SDWIS) Violations
WATER & SEWER COMMISSION 4 OF ST MARY 9,709 15
CITY OF PATTERSON WATER SYSTEM 8,456 9
CITY OF FRANKLIN WATER SUPPLY 8,325 191
ST MARY WATER & SEWER COMM #3 7,828 4
ST MARY PARISH W&S #2 BAYOU VISTA 5,379 0
ST MARY PARISH WATER SEWERAGE COMM 1 2,823 4
PORT OF WEST ST MARY 400 16
BERWICK BAYOU VISTA WW COMMISSION 0 5

TRI Facilities (17)

# Facility Total Releases
1 Cabot Corp Canal Plant 2.6M lbs
2 Bollinger Marine Fabricators LLC 804.5K lbs
3 Orion Engineered Carbons-Ivanhoe Carbon Black Plant 400.0K lbs
4 Cameron International Corp 293.7K lbs
5 Birla Carbon USA Inc 179.3K lbs
6 Conrad Shipyard LLC (deepwater Yard) 164.8K lbs
7 Azz Galvanizing - Morgan City 76.7K lbs
8 Cameron International Corp 68.1K lbs
9 Pelican Processing Plant 7.7K lbs
10 Enterprise Gas Processing LLC - Neptune Gas Plant 4.5K lbs
11 New Industries LLC 235 lbs
12 Twin Brothers Marine LLC 103 lbs
13 Conrad Shipyard LLC (main Yard) 65 lbs
14 Conrad Shipyard Amelia LLC 61 lbs
15 Baker Hughes Oilfield Operations LLC 3 lbs
16 D & D Welding/fab Inc. 0 lbs
17 Halliburton Berwick Baroid 0 lbs

Cities in St. Mary Parish (7)

Centerville
4 facilities · 1 water
Franklin
2 facilities · 2 water
Patterson
2 facilities · 2 water
Berwick
1 facilities · 2 water
Amelia
1 facilities · 1 water
Bayou Vista
1 facilities · 0 water
Charenton
0 facilities · 1 water

Frequently Asked Questions

What is the environmental risk level in St. Mary Parish, Louisiana?
St. Mary Parish, LA has an environmental risk score of 54/100 (Moderate Risk), based on 17 TRI facilities, 0 Superfund sites, and 8 water systems on record. 7 water systems have health-based violations. Source: EPA TRI, SDWIS, and Superfund NPL.
Are there Superfund sites in St. Mary Parish?
No Superfund National Priorities List (NPL) sites are currently registered in St. Mary Parish, LA in the EPA database.
How many toxic release facilities are in St. Mary Parish?
St. Mary Parish, LA has 17 TRI-reporting facilities on record with the EPA Toxic Release Inventory, with a combined total of 4.6M lbs in reported toxic releases. TRI facilities self-report annual chemical release data to the EPA.
What is the air quality in St. Mary Parish?
Air quality monitoring data (EPA AQS) is not available for St. Mary Parish, LA. This may indicate no EPA monitoring stations are located in the county. For regional air quality data, see the state environmental profile or visit EPA's AirNow.gov.
Is the drinking water safe in St. Mary Parish?
St. Mary Parish, LA has 8 EPA-regulated water systems. 7 systems have reported health-based violations (MCL exceedances). A past violation does not necessarily mean water is currently unsafe. For current water quality, contact your local water utility. Source: EPA SDWIS.
What environmental agencies cover St. Mary Parish?
Environmental compliance in St. Mary Parish, Louisiana is overseen by the U.S. Environmental Protection Agency (EPA) at the federal level and the Louisiana state environmental agency. Facilities report to the EPA Toxic Release Inventory, water systems are regulated under the Safe Drinking Water Act, and contaminated sites are managed under the Superfund program. Contact your state environmental agency for local concerns.

What does this county environmental profile show?

This county environmental profile rolls up EPA Toxics Release Inventory facility reports, Safe Drinking Water Information System public-water-system filings, and Superfund National Priorities List sites for the county boundary defined by the U.S. Census Bureau. Facility counts reflect facilities with a reporting address inside the county, not where downstream environmental effects may be observed. Population figures are from the most recent Census ACS 5-year estimate. The county detail page is updated whenever the upstream EPA programs publish revised data; see the methodology page for the documented ingest cadence and the editorial choices governing how aggregations are computed.

Related

Data sourced from U.S. EPA environmental datasets. See our methodology for details. Retrieved and formatted by PlainEnviro