Environmental data

[A]

Oil and gas industry guidelines (IPIECA/API/OGP) indicate that there are a number of sources of uncertainty that can contribute to the overall uncertainty of a corporate emissions inventory. CO2 equivalent is a term used to express the total emissions of the major greenhouse gases, including CO2, methane, nitrous oxide and hydrofluorocarbons. We have updated our 2010 figures following recalculation of the data.

[B]

We have updated our 2010 figures following recalculation of the data.

[C]

Nigeria includes SPDC onshore operations (1.9 million tonnes flared in 2011) and SNEPCo offshore operations (0.1 million tonnes flared in 2011).

[D]

Flaring from the start-up of the Pearl GTL plant in Qatar amounted to 0.4 million tonnes of hydrocarbon in 2011. Flaring in Iraq amounted to 0.3 million tonnes of hydrocarbon in 2011.

[E]

Data reported in accordance with IPIECA/API/OGP guidelines. We have updated our figures following recalculation of the data.

[F]

The data includes mining and upgrading operations. It does not include in situ production. We have updated our figures following recalculation of the data.

[G]

Indexed to 2002; based on Solomon Associates Energy Intensity Index 2006 methodology.

[H]

We have updated our 2010 figure following review of the data.

[I]

All spill volumes and numbers are for spills over 100 kilograms.

[J]

As of the end of March 2012, there were two spills under investigation in Nigeria that may result in adjustments to the 2011 data.

[K]

All sabotage and theft related spills have occurred in Nigeria except in 2007 (0.7 thousand tonnes outside Nigeria) and 2006 (0.6 thousand tonnes outside Nigeria).

[L]

A single spill at the Bonga field offshore Nigeria amounted to 4.8 thousand tonnes in 2011. Nigeria includes SPDC onshore operations and SNEPCo offshore operations.

[M]

We have updated our 2010 figure following review of the data. The number of operational spills reported for 2004 and 2005 also contain a small number of hurricane spills.

[N]

Nigeria includes SPDC onshore operations (63 operational spills in 2011) and SNEPCo offshore operations (1 operational spill in 2011).

[O]

The increase in 2011 is due to disposal of water containing low levels of selenium in Canada.

n/c Not calculated.