Home Search Emissions Pollutants About the Database

Marathon Ashland Petroleum (3165), Garyville

Releases of Hydrogen Cyanide

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

FCCU Scrubber Vent (EQT#165, EIQ# 86-74)
Cause: There was no upset. The unit is operating as designed. Marathon performed the original stack test in response to learning of the possibility of the existence of HCN from a stack test performed at the Robinson, IL refinery. Robinson performed the stack test per the ICR issued by the U.S. EPA in March 2011. An incorrect stack diameter of 91.75 inches was use to calculate the mass emission rate. The correct stack diameter is 156 inches. Using the lower stack diameter caused the emission rate to be under reported in the 2012 report. 01/27/12- Caller reports a continuous release of hydrogen cyanide through the fluidized catalitic cracking unit. Upper bound reported as 150 lbs/day. http://www.nrc.uscg.mil/reports/rwservlet?standard_web+inc_seq=1001479 10/08/13- Caller states that based on updated stack test, hydrogen cyanide is being released over the permit limit (198 lbs/day). It is from fluidize catalytic cracking unit and it is continuous. The facility is permitted to release 235 lbs/day. Upper bound of release is 433 lbs/day. http://www.nrc.uscg.mil/reports/rwservlet?standard_web+inc_seq=1062414

Followup: Yes

Notes: The emissions were found during a stack test of the FCU and the Title V operating Permit will be modified to include these emissions. There were no remedial actions taken. A permit application is being prepared for submittal to the LDEQ. Additional testing will be performed November 2013 to verify emissions. Report states that modeling has been performed to determine teh ambient air concentrations and ensure that they are less than the Louisiana Toxic Air Program Ambient Air Standards for Hydrogen Cyanide.
158,045.0 pounds