Report on ExxonMobil Torrance Refinery Incident of February 18, 2015
SCAQMD Response and Sampling & Analysis Efforts
Description of the Incident
(Based on information obtained by SCAQMD and provided by ExxonMobil)
At around 9 a.m. on February 18, 2015, there was an explosion at the ExxonMobil Torrance Refinery which blew off sections of the Electrostatic Precipitator (ESP), venting the Fluid Catalytic Cracking Unit (FCCU), and released spent catalyst into the air which deposited it in the neighborhood on top of cars and homes and other areas around the refinery. The explosion was reported to be due to over pressurization in the ESP unit. The ESP is a piece of air pollution control equipment which controls particulate matter (PM) emissions from the FCCU and is a relatively new unit, permitted in December 2008 and has been in operation since 2009/2010. The FCCU was not in operation and was not being vented to the ESP at the time of the incident. ExxonMobil was planning to restart the FCCU this week, therefore, the FCCU was not hydrocarbon freed. The ESP unit did not have any vent gas from FCCU going through the unit at the time of the incident. The cause of over pressure and explosion of the ESP is not yet provided and is under investigation.
The explosion caused collateral damage to the nearby units including a Pre-Treater and a water De-mineralizing unit (which removes minerals from feed water for the refinery Boilers). The damage to the Pre-Treater unit resulted in a hydrocarbon leak that caused the unit to be vented to the flares, causing significant flaring and smoke. At this time, ExxonMobil started to shutdown other units, such as the Hydrogen Unit, which also contributed to additional flaring, and initiated reducing the refinery throughput.
Notifications
At 9:17 a.m. ExxonMobil filed a breakdown notification regarding the incident with SCAQMD via telephone. At 9:24 a.m., ExxonMobil also filed a Hazardous Material Spill Report with the Governor’s Office of Emergency Services, indicating that the refinery has released more than 500 lbs of SOx, has visible smoke and closure of Del Amo Blvd due to flaring. Also by this time, SCAQMD had received over a dozen air quality complaints about smoke, flaring and ash fall out.
SCAQMD Response
Upon receipt of breakdown notification and complaints, SCAQMD immediately dispatched 3 Inspectors from the Long Beach Compliance office to investigate the incident and respond to the complaints. The SCAQMD Emergency Response Team was also put on high alert and dispatched into the field. The SCAQMD staff observed fall out in an area downwind of the
refinery and collected samples from the material deposited on top of cars and on the ground in the area. Also SCAQMD staff took air samples using portable analyzers (GC/MS and DustTracks). In addition, canister grab samples were also taken around the refinery. SCAQMD Inspectors were on-site at the refinery until around 8:30 p.m. on February 18th and returned back to the refinery the following days to continue our sampling and investigations.
Sampling & Analysis
SCAQMD compliance and monitoring staff responded to reports of an explosion at the ExxonMobil refinery on Wednesday morning, February 18, 2015. SCAQMD monitoring staff arrived on scene with monitoring instrumentation within an hour and a half of the incident, however, measurements did not proceed immediately upon arrival due to safety precautions related to reports about the potential release of radioactive materials at the scene. When confirmed that the radiation concern was indeed unfounded shortly before noon, near real time monitoring around the refinery began immediately for hydrocarbons, particulate matter (PM), and sulfur compounds. In addition, canister and fallout samples were collected and analyzed for metals, hexavalent chromium (CrVI), and asbestos. Included in this report are four technical appendices. Appendix I include a map of the locations where air monitoring was conducted and where samples were collected. Appendices II through IV include detailed results of the samples.
Overall findings of the near real time measurements indicated that hydrocarbons, PM, and sulfur compound levels were consistent with level that are typically seen in outdoor air. Bulk samples of fallout found on automobiles and at Mansel Avenue and Delthorne Park contained metals consistent with those used in the refinery’s FCCU catalyst and as collected by ESP. No asbestos was found in the fallout samples, however those samples did contain fiberglass and glass wool. Fallout samples contained less than 60 parts per billion (ppb) CrVI, which is over 250 times below the California state (OEHHA) Residential Soil Screening level.
Near Real Time Measurements
1. Portable gas chromatograph/mass spectrometers (GC/MSs) were used to measure hydrocarbons in the air at seven (7) locations around the refinery. All readings were below the instrument’s detection limit of 100 ppb. Details providing sampling locations, times and results are shown in Appendix II.
2. Two Jerome portable hydrogen sulfide (H2S) analyzers were used to measure sulfur compounds in the air at locations around the refinery. All readings showed 11 ppb or less total reduced sulfur, with no distinction between upwind and downwind locations. These values are below the level of the California Ambient Air Quality Standard of 30 ppb.
3. DustTrack portable particulate monitors provided continuous PM measurements. These devices provide an indication of PM levels and are used to compare PM concentration at upwind and downwind locations of the incident. The PM levels observed with the
DustTrack showed levels of PM that were similar upwind and downwind, showing no gradient from the incident. Also the levels were consistent with PM measurements from SCAQMD’s South Long Beach monitoring site and also consistent with typical ambient PM levels.
4. To monitor potential impacts of on-going flaring at the refinery, two (2) E-BAM stationary PM monitors were deployed downwind of the refinery on Thursday, February 19, 2015. The E-BAMs are based upon PM measurement principles used with instrumentation at the fully equipped air monitoring stations. Results of the E-BAM monitoring have shown that PM levels in the area downwind of the refinery have been consistent with typical Basin levels and those observed at other SCAQMD air monitoring stations located throughout the Basin.
Sampling and Analysis
Canister Samples
To determine levels of gaseous air toxics, one upwind and three downwind canisters samples were collected between 1:36 pm and 3:34 pm on February 18th. These samples are considered instantaneous or grab samples. These were returned to the SCAQMD laboratory and analyzed for total hydrocarbons as well as detailed analysis to identify individual air toxic compounds on a GC/MS. The canister analysis targets over 50 compounds, however, other compounds can be found, identified and levels estimated if present. Samples were analyzed using SCAQMD’s Standard Operating Procedures (SOP), following EPA Methods TO-14, including rigorous quality assurance (QA) measures. The results were within the range of concentrations typically measured in the Los Angeles general area and are shown in Appendix III.
Bulk Fallout Samples
Scrapings were collected from two vehicles on Mansel Street and one on Hawthorne Blvd. Additional bulk fallout samples were collected at Delthorne Park. These samples were analyzed at the SCAQMD laboratory for asbestos, hexavalent chromium (CrVI) and other metals.
Microscopic analysis of fallout samples for asbestos and other materials was determined by polarized light microscopy and followed NIST and NVLAP SOPs. No asbestos was found in the fallout samples; however those samples did contain fiberglass and glass wool used in typical commercial insulation material.
Fallout samples were analyzed for hexavalent chromium (CrVI) using SCAQMD’s SOP for the determination of CrVI by Ion Chromatograph (IC). Fallout samples contained less than 60 ppb CrVI, which is over 250 times below the California state Office of Environmental Health Hazard Assessment (OEHHA) Residential Soil Screening level.
Fallout sample’s metal content was compared to levels found in OEHHA’s Soil Screening Table which can be found at: http://www.oehha.ca.gov/risk/chhsltable.html , as well as compared to
typical soil levels as found in the literature. Samples were extracted following a slight modification to SCAQMD SOP #00096 which utilizes a nitric acid and microwave digestion/extraction of the sample followed by
SCAQMD Response and Sampling & Analysis Efforts
Description of the Incident
(Based on information obtained by SCAQMD and provided by ExxonMobil)
At around 9 a.m. on February 18, 2015, there was an explosion at the ExxonMobil Torrance Refinery which blew off sections of the Electrostatic Precipitator (ESP), venting the Fluid Catalytic Cracking Unit (FCCU), and released spent catalyst into the air which deposited it in the neighborhood on top of cars and homes and other areas around the refinery. The explosion was reported to be due to over pressurization in the ESP unit. The ESP is a piece of air pollution control equipment which controls particulate matter (PM) emissions from the FCCU and is a relatively new unit, permitted in December 2008 and has been in operation since 2009/2010. The FCCU was not in operation and was not being vented to the ESP at the time of the incident. ExxonMobil was planning to restart the FCCU this week, therefore, the FCCU was not hydrocarbon freed. The ESP unit did not have any vent gas from FCCU going through the unit at the time of the incident. The cause of over pressure and explosion of the ESP is not yet provided and is under investigation.
The explosion caused collateral damage to the nearby units including a Pre-Treater and a water De-mineralizing unit (which removes minerals from feed water for the refinery Boilers). The damage to the Pre-Treater unit resulted in a hydrocarbon leak that caused the unit to be vented to the flares, causing significant flaring and smoke. At this time, ExxonMobil started to shutdown other units, such as the Hydrogen Unit, which also contributed to additional flaring, and initiated reducing the refinery throughput.
Notifications
At 9:17 a.m. ExxonMobil filed a breakdown notification regarding the incident with SCAQMD via telephone. At 9:24 a.m., ExxonMobil also filed a Hazardous Material Spill Report with the Governor’s Office of Emergency Services, indicating that the refinery has released more than 500 lbs of SOx, has visible smoke and closure of Del Amo Blvd due to flaring. Also by this time, SCAQMD had received over a dozen air quality complaints about smoke, flaring and ash fall out.
SCAQMD Response
Upon receipt of breakdown notification and complaints, SCAQMD immediately dispatched 3 Inspectors from the Long Beach Compliance office to investigate the incident and respond to the complaints. The SCAQMD Emergency Response Team was also put on high alert and dispatched into the field. The SCAQMD staff observed fall out in an area downwind of the
refinery and collected samples from the material deposited on top of cars and on the ground in the area. Also SCAQMD staff took air samples using portable analyzers (GC/MS and DustTracks). In addition, canister grab samples were also taken around the refinery. SCAQMD Inspectors were on-site at the refinery until around 8:30 p.m. on February 18th and returned back to the refinery the following days to continue our sampling and investigations.
Sampling & Analysis
SCAQMD compliance and monitoring staff responded to reports of an explosion at the ExxonMobil refinery on Wednesday morning, February 18, 2015. SCAQMD monitoring staff arrived on scene with monitoring instrumentation within an hour and a half of the incident, however, measurements did not proceed immediately upon arrival due to safety precautions related to reports about the potential release of radioactive materials at the scene. When confirmed that the radiation concern was indeed unfounded shortly before noon, near real time monitoring around the refinery began immediately for hydrocarbons, particulate matter (PM), and sulfur compounds. In addition, canister and fallout samples were collected and analyzed for metals, hexavalent chromium (CrVI), and asbestos. Included in this report are four technical appendices. Appendix I include a map of the locations where air monitoring was conducted and where samples were collected. Appendices II through IV include detailed results of the samples.
Overall findings of the near real time measurements indicated that hydrocarbons, PM, and sulfur compound levels were consistent with level that are typically seen in outdoor air. Bulk samples of fallout found on automobiles and at Mansel Avenue and Delthorne Park contained metals consistent with those used in the refinery’s FCCU catalyst and as collected by ESP. No asbestos was found in the fallout samples, however those samples did contain fiberglass and glass wool. Fallout samples contained less than 60 parts per billion (ppb) CrVI, which is over 250 times below the California state (OEHHA) Residential Soil Screening level.
Near Real Time Measurements
1. Portable gas chromatograph/mass spectrometers (GC/MSs) were used to measure hydrocarbons in the air at seven (7) locations around the refinery. All readings were below the instrument’s detection limit of 100 ppb. Details providing sampling locations, times and results are shown in Appendix II.
2. Two Jerome portable hydrogen sulfide (H2S) analyzers were used to measure sulfur compounds in the air at locations around the refinery. All readings showed 11 ppb or less total reduced sulfur, with no distinction between upwind and downwind locations. These values are below the level of the California Ambient Air Quality Standard of 30 ppb.
3. DustTrack portable particulate monitors provided continuous PM measurements. These devices provide an indication of PM levels and are used to compare PM concentration at upwind and downwind locations of the incident. The PM levels observed with the
DustTrack showed levels of PM that were similar upwind and downwind, showing no gradient from the incident. Also the levels were consistent with PM measurements from SCAQMD’s South Long Beach monitoring site and also consistent with typical ambient PM levels.
4. To monitor potential impacts of on-going flaring at the refinery, two (2) E-BAM stationary PM monitors were deployed downwind of the refinery on Thursday, February 19, 2015. The E-BAMs are based upon PM measurement principles used with instrumentation at the fully equipped air monitoring stations. Results of the E-BAM monitoring have shown that PM levels in the area downwind of the refinery have been consistent with typical Basin levels and those observed at other SCAQMD air monitoring stations located throughout the Basin.
Sampling and Analysis
Canister Samples
To determine levels of gaseous air toxics, one upwind and three downwind canisters samples were collected between 1:36 pm and 3:34 pm on February 18th. These samples are considered instantaneous or grab samples. These were returned to the SCAQMD laboratory and analyzed for total hydrocarbons as well as detailed analysis to identify individual air toxic compounds on a GC/MS. The canister analysis targets over 50 compounds, however, other compounds can be found, identified and levels estimated if present. Samples were analyzed using SCAQMD’s Standard Operating Procedures (SOP), following EPA Methods TO-14, including rigorous quality assurance (QA) measures. The results were within the range of concentrations typically measured in the Los Angeles general area and are shown in Appendix III.
Bulk Fallout Samples
Scrapings were collected from two vehicles on Mansel Street and one on Hawthorne Blvd. Additional bulk fallout samples were collected at Delthorne Park. These samples were analyzed at the SCAQMD laboratory for asbestos, hexavalent chromium (CrVI) and other metals.
Microscopic analysis of fallout samples for asbestos and other materials was determined by polarized light microscopy and followed NIST and NVLAP SOPs. No asbestos was found in the fallout samples; however those samples did contain fiberglass and glass wool used in typical commercial insulation material.
Fallout samples were analyzed for hexavalent chromium (CrVI) using SCAQMD’s SOP for the determination of CrVI by Ion Chromatograph (IC). Fallout samples contained less than 60 ppb CrVI, which is over 250 times below the California state Office of Environmental Health Hazard Assessment (OEHHA) Residential Soil Screening level.
Fallout sample’s metal content was compared to levels found in OEHHA’s Soil Screening Table which can be found at: http://www.oehha.ca.gov/risk/chhsltable.html , as well as compared to
typical soil levels as found in the literature. Samples were extracted following a slight modification to SCAQMD SOP #00096 which utilizes a nitric acid and microwave digestion/extraction of the sample followed by
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