Original sentence: BP challenged the higher figure, saying that the government overestimated the volume.BP originally estimated a flow rate of.Internal emails released in 2013 showed that one BP employee had estimates that matched those of the FRTG, and shared the data with supervisors, but BP continued with their lower number.The Flow Rate Technical Group (FRTG) estimated the flow rate was.The company argued that government figures do not reflect over  of oil that was collected or burned before it could enter the Gulf waters.The total estimated volume of leaked oil approximated  with plus or minus 10% uncertainty, including oil that was collected, making it the largest accidental oil spill in history
Edited sentence: , including oil that was collected.BP also argues that government figures do not reflect over  of oil that was collected or burned before it could enter the Gulf waters.BP challenges this figure, saying that the government overestimated the volume; email released in 2013 show that one BP employee's estimate matched those of the FRTG, but this was overruled by an external consultants.The total estimated volume of leaked oil approximated  with plus or minus 10% uncertainty.This makes it the largest accidental oil spill in history.While originally BP authorities gave their best estimate of a flow rate of , according to the Flow Rate Technical Group, (FRTG)  was a more realistic figure