St. John The Baptist Parish, LA

Moderate Risk (47/100)

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. John The Baptist Parish in Louisiana · Population: 41,342

TRI sites such as Dupont Pontchartrain Works; Marathon Petroleum Co LP; Pinnacle Polymers; SDWIS systems such as ST JOHN WATER DISTRICT 3; ST JOHN WATER DISTRICT 1; ST JOHN WATER DISTRICT 2 anchor St. John The Baptist Parish, LA's EPA extract. Derived burden score 47/100 (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. John The Baptist Parish include ST JOHN WATER DISTRICT 1; ST JOHN WATER DISTRICT 2; PLEASURE BEND WATER SUPPLY, while Dupont Pontchartrain Works leads reported TRI pounds among local Form R filers. AQS median AQI 36 / peak 105 in 2024.

Burden score 47/100 (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. John The Baptist 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. John The Baptist Parish, LA: EPA TRI 2023 reporting year

2022 → 2023

Same facilities, both years

-0.7%

11 facilities that filed in 2022 and 2023

Whole inventory

-0.7%

2.2 million lb → 2.2 million lb, every facility that filed

  • St. John The Baptist Parish, LA's total reported releases fell from 2.2 million lb in 2022 to 2.2 million lb in 2023, based on EPA TRI filings.
  • St. John The Baptist Parish, LA's off-site transfers rose from 61.6 thousand lb in 2022 to 68.3 thousand lb in 2023, based on EPA TRI filings.
  • St. John The Baptist Parish, LA's air releases rose from 742.6 thousand lb in 2022 to 819.7 thousand lb in 2023, based on EPA TRI filings.
  • St. John The Baptist Parish, LA's land releases fell from 1.1 million lb in 2022 to 1.1 million lb in 2023, based on EPA TRI filings.
County population (Census ACS)
41,342
TRI Facilities
12
Water Systems
4
Superfund Sites
0
Total Releases
10.1M lbs

Air Quality History (2020–2024)

EPA Air Quality Index (AQI) data showing how many days per year fall into each air quality category.

Year Good Moderate Unhealthy (SG) Max AQI
2024 320 (89%) 37 2 105
2023 315 (88%) 39 4 112
2022 335 (95%) 16 0 80
2021 327 (97%) 8 1 108
2020 341 (97%) 10 0 80
2024 Good Air Quality: 89% of days
Unhealthy days: 2
Median AQI: 36

Source: EPA Air Quality System (AQS) Annual AQI by County AQI categories: Good (0-50), Moderate (51-100), Unhealthy for Sensitive Groups (101-150), Unhealthy (151-200), Very Unhealthy (201-300), Hazardous (301+)

For real-time air quality readings and pollutant breakdowns in Louisiana, see the EPA's AirNow.gov.

Water Systems (4)

System System pop (SDWIS) Violations
ST JOHN WATER DISTRICT 3 31,965 0
ST JOHN WATER DISTRICT 1 10,484 12
ST JOHN WATER DISTRICT 2 3,702 1
PLEASURE BEND WATER SUPPLY 528 36

TRI Facilities (12)

# Facility Total Releases
1 Dupont Pontchartrain Works 5.1M lbs
2 Marathon Petroleum Co LP 3.6M lbs
3 Pinnacle Polymers 489.0K lbs
4 Denka Performance Elastomer LLC 427.8K lbs
5 Air Products & Chemicals Inc - Garyville Smr 129.4K lbs
6 Evonik Corp 89.6K lbs
7 Clariant Corporation - Reserve Site 71.2K lbs
8 Mt. Airy Terminal LLC 63.4K lbs
9 Nalco Co 51.3K lbs
10 Stockhausen Superabsorber LLC 31.1K lbs
11 Pvs Dx Inc. 563 lbs
12 Championx -- Garyville Facility 542 lbs

Cities in St. John The Baptist Parish (4)

Garyville
5 facilities · 0 water
Reserve
3 facilities · 0 water
Laplace
2 facilities · 4 water
Mount Airy
2 facilities · 0 water

Frequently Asked Questions

What is the environmental risk level in St. John The Baptist Parish, Louisiana?
St. John The Baptist Parish, LA has an environmental risk score of 47/100 (Moderate Risk), based on 12 TRI facilities, 0 Superfund sites, and 4 water systems on record. 3 water systems have health-based violations. Source: EPA TRI, SDWIS, and Superfund NPL.
Are there Superfund sites in St. John The Baptist Parish?
No Superfund National Priorities List (NPL) sites are currently registered in St. John The Baptist Parish, LA in the EPA database.
How many toxic release facilities are in St. John The Baptist Parish?
St. John The Baptist Parish, LA has 12 TRI-reporting facilities on record with the EPA Toxic Release Inventory, with a combined total of 10.1M lbs in reported toxic releases. TRI facilities self-report annual chemical release data to the EPA.
What is the air quality in St. John The Baptist Parish?
In 2024, St. John The Baptist Parish, LA recorded a median AQI of 36 and a peak AQI of 105. 89% of monitored days had "Good" air quality (AQI 0–50). Source: EPA Air Quality System (AQS) Annual AQI by County.
Is the drinking water safe in St. John The Baptist Parish?
St. John The Baptist Parish, LA has 4 EPA-regulated water systems. 3 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. John The Baptist Parish?
Environmental compliance in St. John The Baptist 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