The Bureau tracks spill incidents 1 barrel and greater in size of petroleum and other toxic substances resulting from Federal Outer Continental Shelf (OCS) oil and gas activities. The Bureau has historically produced counts and summaries for spills greater than or equal to 50 barrels (2,100 gallons). The tables below provide counts for spills of 50 barrels or greater, by year and by OCS Region. The counts are linked to summaries describing the circumstances surrounding each spill of 50 barrels or greater for that Region that year. One barrel (bbl) equals 42 U.S. gallons.
Effective July 17, 2006, MMS revised the regulations for incident reporting. This regulation did not change the reporting requirement for Spills. Currently all spills of 1 barrel or more must be reported.
- Spill Summaries OCS Spills ≥ 50 Barrels CY 1964–2011
- Spill Summaries OCS Spills 10 to 49 Barrels CY 1970–2011
- All Petroleum Spills ≥ 1 Barrel from OCS Oil & Gas Activities by Size Category and Year, 1964-2010
Cross tabulation of spill counts and barrels spilled for OCS petroleum spills of one barrel (42 gallons) and greater by spill size category, year and spill source (Platform, Pipeline, and Vessel). Petroleum spills include crude oil, condensate (a liquid product of natural gas), and refined products such as diesel, hydraulic oil, lube oil, mineral oil, etc. Synthetic oil products are excluded.
OCS Spills ≥50 Barrels by Category:
OCS Spill Incidents 2008-2011
| Number of Spills > 50 Barrels* | 2008 | 2009 | 2010 | 2011 | ||||
|---|---|---|---|---|---|---|---|---|
| Type of Spill | GOM | PAC | GOM | PAC | GOM | PAC | GOM | PAC |
| Crude Oil & Natural Gas Condensate | 19 | 0 | 4 | 0 | 3 | 0 | 0 | 0 |
| Refined Petroleum*, e.g. Diesel, Lube Oil | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Synthetic-Based Fluids*, ** | 2 | 0 | 4 | 0 | 2 | 0 | 0 | 0 |
| Chemicals, e.g., Zinc, Bromide, Glycol, Methanol | 12 | 0 | 3 | 0 | 1 | 0 | 0 | 0 |
| Regional Totals for the Year | 331,2,3 | 0 | 112 | 0 | 6 | 0 | 0 | 0 |
| Combined Total for the Year | 33 | 11 | 6 | 0 | ||||
1 Number of spill events with total spillage of 50 bbl or more. Column does not add because spills include multi-product spills where no individual product was 50 bbl or more, and spills which involved the loss of 50 bbl each or more of two or more individual products.
2 Some crude/condensate spills in 2008 and 2009 are seepage (including observations less than one bbl) totaling 50 bbl or greater in a calendar quarter from hurricane-damaged structures undergoing or awaiting decommissioning.
3 2008 includes Hurricanes Gustav and Ike 'passive' spills, unseen spills based on inventories of products lost from destroyed structures which were thoroughly dispersed during the storms. Petroleum losses were minimized due to the successful operation of safety valves, and all oil and gas operations being shut in prior to the storms.
* In the case of drilling muds, only the base fluids (e.g. diesel, mineral oil, synthetic fluid, etc.) are counted as pollution. A spill of 100 bbl of 65% diesel-based mud is counted as a 65 barrel diesel spill. A 100 bbl spill of 55% synthetic-based mud is counted as a 55 barrel synthetic-based fluid spill.
** In deepwater drilling, synthetic-based muds (SBM’s) are preferred over petroleum oil-based muds (OBM’s) due to the SBM’s superior performance properties. The synthetic base fluid used in SBM’s are less toxic to the marine environment and have the potential to biodegrade. Only the synthetic base fluids are counted as pollution. SBM's were first introduced in the Gulf of Mexico around 1999. Petroleum oil-based muds (OBM's) were the predominant muds prior to this time (generally with diesel or mineral oil as the base), and are still used outside of deepwater.
SOURCE: TIMS & MMS Spill Database as of 3-September-2009
OCS Spill Incidents 2004-2007
| Number of Spills > 50 Barrels* | 2004 | 2005 | 2006 | 2007 | ||||
|---|---|---|---|---|---|---|---|---|
| Type of Spill | GOM | PAC | GOM | PAC | GOM | PAC | GOM | PAC |
| Crude Oil & Natural Gas Condensate | 11 | 0 | 32 | 0 | 7 | 0 | 1 | 0 |
| Refined Petroleum*, e.g. Diesel, Lube Oil | 4 | 0 | 7 | 0 | 0 | 0 | 0 | 0 |
| Synthetic-Based Fluids** | 5 | 0 | 5 | 0 | 5 | 0 | 2 | 0 |
| Chemicals, e.g., Zinc, Bromide, Glycol, Methanol | 4 | 0 | 6 | 0 | 2 | 0 | 1 | 0 |
| Regional Totals for the Year | 221,2,3 | 0 | 401,3 | 0 | 14 | 0 | 4 | 0 |
| Combined Total for the Year | 22 | 49 | 14 | 4 | ||||
1 Number of spill events with total spillage of 50 bbl or more. Column does not add because spills include multi-product spills where no individual product was 50 bbl or more, and spills which involved the loss of 50 bbl each or more of two or more individual products.
2 Some crude/condensate spills in 2006 are seepage (including observations less than one bbl) totaling 50 bbl or greater in a calendar quarter from hurricane-damaged structures undergoing or awaiting decommissioning.
3 'Passive' spills, unseen spills based on inventories of products lost from destroyed structures which were thoroughly dispersed during the storms, are included in 2004 (Hurricane Ivan, and 2005 (Hurricanes Katrina & Rita). Petroleum losses were minimized due to the successful operation of safety valves, and all oil and gas operations being shut in prior to the storms.
* In the case of drilling muds, only the base fluids are counted as pollution. Spills where the whole mud volume was 50 barrels or greater but the base oil/fluid was less than 50 barrels are annotated at the end of the narratives (two in 2004, one in 2005, and four in 2006).
** In deepwater drilling, synthetic-based muds (SBM’s) are preferred over petroleum oil-based muds (OBM’s) due to the SBM’s superior performance properties. The synthetic base fluid used in SBM’s are less toxic to the marine environment and have the potential to biodegrade. Only the synthetic base fluids are counted as pollution. SBM's were first introduced in the Gulf of Mexico around 1999. Petroleum oil-based muds (OBM's) were the predominant muds prior to this time (generally with diesel or mineral oil as the base), and are still used outside of deepwater.
SOURCE: TIMS & MMS Spill Database as of 3-September-2009
OCS Spill Incidents 2000-2003
| Number of Spills > 50 Barrels* | 2000 | 2001 | 2002 | 2003 | ||||
|---|---|---|---|---|---|---|---|---|
| Type of Spill | GOM | PAC | GOM | PAC | GOM | PAC | GOM | PAC |
| Crude Oil & Natural Gas Condensate | 3 | 0 | 1 | 0 | 1 | 0 | 0 | 0 |
| Refined Petroleum*, e.g. Diesel, Lube Oil | 0 | 0 | 0 | 0 | 2 | 0 | 3 | 0 |
| Synthetic-Based Fluids** | 5 | 0 | 5 | 0 | 7 | 0 | 7 | 0 |
| Chemicals, e.g., Zinc, Bromide, Glycol, Methanol | 0 | 0 | 3 | 0 | 2 | 0 | 2 | 0 |
| Regional Totals for the Year | 71 | 0 | 9 | 0 | 122 | 0 | 12 | 0 |
| Combined Total for the Year | 7 | 9 | 12 | 12 | ||||
* In the case of drilling muds, only the base fluids are counted as pollution. Spills where the whole mud volume was 50 barrels or greater but the base oil/fluid was less than 50 barrels are annotated at the end of the narratives (two in 2004, one in 2005, and four in 2006).
** In deepwater drilling, synthetic-based muds (SBM’s) are preferred over petroleum oil-based muds (OBM’s) due to the SBM’s superior performance properties. The synthetic base fluid used in SBM’s are less toxic to the marine environment and have the potential to biodegrade. Only the synthetic base fluids are counted as pollution. SBM's were first introduced in the Gulf of Mexico around 1999. Petroleum oil-based muds (OBM's) were the predominant muds prior to this time (generally with diesel or mineral oil as the base), and are still used outside of deepwater.
1 Number of spill events with total spillage of 50 bbl or more. Column does not add because spills include multi-product spills where no individual product was 50 bbl or more, and spills which involved the loss of 50 bbl each or more of two or more individual products.
2 2002 includes 'passive' spills from Hurricane Lili, unseen spills based on inventories of products lost from destroyed structures which were thoroughly dispersed during the storms. Petroleum losses were minimized due to the successful operation of safety valves, and all oil and gas operations being shut in prior to the storms.
SOURCE: TIMS & MMS Spill Database as of 3-September-2009
OCS Spill Incidents 1996-1999
| Number of Spills > 50 Barrels* | 1996 | 1997 | 1998 | 1999 | ||||
|---|---|---|---|---|---|---|---|---|
| Type of Spill | GOM | PAC | GOM | PAC | GOM | PAC | GOM | PAC |
| Crude Oil & Natural Gas Condensate | 0 | 1 | 1 | 0 S | 3 | 0 | 2 | 0 |
| Refined Petroleum*, e.g. Diesel, Lube Oil | 2 | 0 | 0 | 0 | 1 | 0 | 1 | 0 |
| Synthetic-Based Fluids** | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 |
| Chemicals, e.g., Zinc, Bromide, Glycol, Methanol | 1 | 0 | 2 | 0 | 5 | 0 | 1 | 0 |
| Regional Totals for the Year | 3 | 1 | 3 | 0s | 9 | 0 | 5 | 0 |
| Combined Total for the Year | 4 | 3 | 91 | 5 | ||||
*In the case of drilling muds, only the base fluids are counted as pollution. Spills where the whole mud volume was 50 barrels or greater but the base oil/fluid was less than 50 barrels are annotated at the end of the narratives (two in 2004, one in 2005, and four in 2006).
** In deepwater drilling, synthetic-based muds (SBM’s) are preferred over petroleum oil-based muds (OBM’s) due to the SBM’s superior performance properties. The synthetic base fluid used in SBM’s are less toxic to the marine environment and have the potential to biodegrade. Only the synthetic base fluids are counted as pollution. SBM's were first introduced in the Gulf of Mexico around 1999. Petroleum oil-based muds (OBM's) were the predominant muds prior to this time (generally with diesel or mineral oil as the base), and are still used outside of deepwater.
S In 1997, 163 bbls of Federal OCS production (from Platform Irene) spilled as a result of a pipeline failure in State waters
1 Number of spill events with total spillage of 50 bbl or more. Column does not add because spills include multi-product spills where no individual product was 50 bbl or more, and spills which involved the loss of 50 bbl each or more of two or more individual products.
SOURCE: TIMS & MMS Spill Database as of 3-September-2009
Spills ≥ 50 Barrels (2,100 gal) in State Waters
The Bureau tracks spills which occur on Federal leases in OCS waters, the submerged lands, subsoil, and seabed, lying between the seaward extent of the States' jurisdiction and the seaward extent of Federal jurisdiction (see spills above). The BOEM does not maintain comprehensive data on spills which have occurred in the State's jurisdiction. However, in recent years, MMS occasionally had collected information on State pollution incidents.
State Jurisdiction is defined as follows:
- Texas and the Gulf coast of Florida are extended 3 marine leagues (9 nautical miles) seaward from the baseline from which the breadth of the territorial sea is measured.
- Louisiana is extended 3 imperial nautical miles (imperial nautical mile = 6080.2 feet) seaward of the baseline from which the breadth of the territorial sea is measured.
- All other States' seaward limits are extended 3 nautical miles (approximately 3.3 statute miles) seaward of the baseline from which the breadth of the territorial sea is measured.
Federal Jurisdiction is defined under accepted principles of international law. The seaward limit is defined as the farthest of 200 nautical miles seaward of the baseline from which the breadth of the territorial sea is measured or, if the continental shelf can be shown to exceed 200 nautical miles, a distance not greater than a line 100 nautical miles from the 2,500-meter isobath or a line 350 nautical miles from the baseline.
Outer Continental Shelf limits greater than 200 nautical miles but less than either the 2,500 meter isobath plus 100 nautical miles or 350 nautical miles are defined by a line 60 nautical miles seaward of the foot of the continental slope or by a line seaward of the foot of the continental slope connecting points where the sediment thickness divided by the distance to the foot of the slope equals 0.01, whichever is farthest.