Home Search Emissions Pollutants About the Database

Marathon Ashland Petroleum (3165), Garyville

Releases of n-Hexane

LDEQ Accident Number
Accident Date
Point Source(s) Notes Amount of Release

Tank 120-6 (EIQ No. 16-74 and EQT 76)
Tank 120-6 (EIQ No. 16-74 and EQT 76) Tank 120-6 (EIQ No. 16-74 and EQT 76)
Cause: It is suspected that there was a failed level indicator on 6/26/05 which led to the product being on the roof of the tank. The cause of the failure in unknown.

Followup: Yes

Notes: The product was transferred to a finished gasoline storage tank. The cause of the failure and subsequent leak are still unknown and are awaiting the results of the investigation.
348.0 pounds

South Flare
Unit 59 South Flare
Cause: A tube leaked on the Unit 15 Hot Separator Overhead Fin Fans at 17:52 hours. At 18:00, the unit was undergoing emergency shutdown procedures and the U15 dump valve was opened to the flare. The incident was a Gas Oil leak in the Unit 15 Hot separator Overhead Fin Fan Exchangers. This leak caused a vapor release of hydrocarbons and hydrogen in addition to a small amount of hydrogen sulfide.

Followup: Yes

Notes: PDF was too large to upload. Unit 15 was depressurized to the South Flare to safely isolate the leaking Overhead Fin Fan. Once the unit pressure was sufficiently low in the unit, the Fin Fans were isolated and the leak stopped. An incident investigation will result in recommendations to prevent recurrence. The reportable quantities for hydrogen sulfide, compressed flammable gas, and compressed flammable liquid were exceeded during this event. A report on October 9, 2013, removed greenhouse gas emissions and revised the estimate of VOC emissions.
952.4 pounds


Unit 59 North Flare
Cause: The initiating incident was a pump seal fire in the Gasoline Desulfurization Unit (Unit 55). The fire was fueled by a leaking seal on the pump. Extinguishing the fire was delayed by inability to close an EIV on the suction side of the pump. This resulted in emergency shutdown of the unit. Two other events also occurred on this day including an upset in Sulfur Plant Unit 234 and a flame-out of the North Flare. Due to the fire and emergency shutdown of the Gasoline Desulfurization Unit, the Fluid Catalytic Cracking Unit cut feed, sending vent gas to the North Flare. Process vent gas was sent to the North Flare which increased the steam to the flare suddenly, snuffing the flare out.

Followup: Yes

Notes: PDF too large to upload (109 pages) To re-light the North Flare, steam was gradually decreased and natural gas was added to the flare gas to allow the two available igniters to relight the North Flare. Parts to repair the North Flare pilot system were already on order when this incident occurred. The North Flare was taken out of service when the parts were received and repaired on October 31, 2012. Spare pilot and igniter assemblies are now in stock so that repairs can be made in a timely fashion if an incident like this is to occur again. Total amount of pollutants released was 59438.44 lbs, but 90% was claimed to be efficiently burned off, resulting in 5943.59 lbs that were actually released. The reportable quantity for Highly Reactive Volatile Organic Compounds (HRVOCs) (100 pounds) was exceeded during the 24 hour period.
19.8 pounds

Emissions from Flare
emissions from flare and Unit 45 Thermal Oxidizer
Cause: Marathon experienced a partial power outage caused by a malfunctioning substation in the refinery resulted in multiple pieces of equipment in the refinery losing power. Low pressure stripper Offgas flared in the South Flare due to partial power outage. Enterprise incident due to a plant farther downstream that had uncharacteristically ceased operation due to an upset condition. The pressure safety valve, as designed, released discharging natural gas to atmosphere due to high pressure on the pipeline caused by the upset condition farther down the line. Emission points involved were the Unit 59 North Flare and the Unit 45 Thermal Oxidizer.

Followup: No

Notes: Marathon power was restored and the equipment that was shutdown was restarted to minimize further releases. An incident investigation will result in recommendation items designed to prevent the recurrence of this event. High sulfur dioxide from one of the thermal oxidizer stacks in Unit 45 and in addition to a small amount of Unit 15 low pressure stripper offgas was flared which contains a small amount of hydrogen sulfide which is converted to sulfur dioxide in the North Flare. Emission points involved were the Unit 59 North Flare and the Unit 45 Thermal Oxidizer. Enterprise personnel immediately began the process of taking the plant down in order to end the release event. Amount of natural gas released is above reportable quantity.

leak from process line in U263 piperack
Cause: On June 29, a pinhole leak was discovered in the LPG feedline from U212 to U222.

Followup: No

Notes: The line was purged with nitrogen and isolated for repairs. The Shift Emergency Response Team was activated and fire monitors were put on the leak to suppress any vapors. Reduced the U212 charge rate to minimize the leak. The line was isolated at battery limits in U222 and U212 to stop the leak. Once the investigation is complete, recommendations will be implemented.
1.7 pounds

U212 Platformer unit
Cause: On May 22, a small leak and hydrogen fire was observed on the 48" flange on the process piping going from cell 1 of the Unit 212 Charge Heater to Reactor #1. The leak was pinhole sized in width and no larger than 1" around the circumference of the flange. The emission point involved was a flange on a process line in the U212 Platformer unit.

Followup: Yes

Notes: Steam was applied to the flange to extinguish the flame and the flange was hot bolted to secure the leak. Once the investigation is complete, recommendations will be implemented. An additional followup on 10/23/13 corrected the initial followup report's emissions data regarding greenhouse gas releases.
0.1 pounds