Phillips 66 Co-Santa Maria Refinery — Emissions Trend

Arroyo Grande, CA · 2019–2023 · Parent: Phillips 66 Co

This page assembles 5 consecutive years of EPA Toxics Release Inventory Form R filings for Phillips 66 Co-Santa Maria Refinery, spanning 2019–2023. Each annual total aggregates on-site air emissions, surface-water discharges, land disposal, and off-site transfers reported by the facility under EPCRA Section 313, which requires disclosure whenever a listed chemical is manufactured, processed, or otherwise used above threshold quantities.

Reported releases opened at 11.5K in 2019 and closed at 815 in 2023 - a decreasing of -92.9% over the window. The chart below stacks the four TRI release media (air, water, land, off-site) and overlays the yearly total. The top contributor by cumulative mass is Hydrogen sulfide at 16.4K, followed by Ethylene at 4.4K.

Because TRI figures are estimated, not metered, year-over-year deltas can reflect methodology revisions, ownership changes, or shifts in what a facility classifies as reportable, not only physical emission changes. Treat the trajectory as a disclosure record, and cross-reference with the EPA Enforcement and Compliance History Online (ECHO) system for the fuller regulatory picture on this petroleum facility.

Overall Trend
↓ Decreasing (-92.9%)
2019 Total
11.5K lbs
2023 Total
815 lbs

Total Releases by Category

Air
Water
Land
Offsite Transfer
02.3K4.6K6.9K9.2K11.5K 20192020202120222023 Pounds Released

Year-over-Year Comparison

Year Total Chemicals YoY Change
2019 11.5K lbs 23
2020 10.3K lbs 23 -10.8%
2021 8.3K lbs 23 -18.7%
2022 8.3K lbs 23 -0.2%
2023 815 lbs 23 -90.2%

Top Chemicals by Year

Chemical 20192020202120222023 Total
Hydrogen sulfide 4.3K 4.1K 3.9K 3.8K 183 16.4K
Ethylene 1.0K 1.2K 1.0K 1.0K 100 4.4K
Ammonia 2.8K 1.3K 57 73 14 4.2K
Toluene 1.0K 1.1K 1.0K 1.0K 83 4.2K
Propylene 629 710 633 623 87 2.7K
Carbonyl sulfide 511 601 515 564 1 2.2K
n-Hexane 259 293 259 258 40 1.1K
Xylene (mixed isomers) 242 248 232 232 73 1.0K
Benzene 232 258 226 223 48 986
Cyclohexane 161 162 160 160 72 716
Phenol 87 79 78 80 45 371
1,2,4-Trimethylbenzene 63 62 61 60 32 278
Naphthalene 53 53 53 52 7 218
Ethylbenzene 44 44 44 44 8 184
Cumene 17 20 17 17 3 74

About This Data

Trend data is sourced from the EPA Toxic Release Inventory (TRI). Facilities report annually. Release quantities are self-reported estimates. Year-over-year changes may reflect changes in production, pollution control measures, reporting methodology, or chemical thresholds.

A decrease in reported releases does not necessarily indicate improved environmental performance, as it may reflect production cutbacks, facility closures, or changes in reporting requirements. Similarly, increases may reflect expanded production rather than degraded environmental practices.

Frequently Asked Questions

Is Phillips 66 Co-Santa Maria Refinery getting cleaner or dirtier?
Based on EPA TRI data from 2019–2023, Phillips 66 Co-Santa Maria Refinery's total toxic releases have decreased by approximately 93%.
What time period does this trend data cover?
This page shows 5 years of EPA Toxic Release Inventory data from 2019–2023. Release quantities are self-reported estimates filed annually by the facility.