Gallons and Gallons

Spills of this magnitude are not new to the developing world. Take Nigeria, for example. Due to poor regulation and pervasive corruption, we do not know for certain how much oil has leaked into the Niger Delta region. In 2006, it was reported that 47 million gallons of oil--a quantity not that different from the new estimates of the Gulf leak --has been spilled in the Delta over the past 50 years. The Nigerian National Petroleum Corp estimates that some 650,000 gallons of oil were spilled in 300 separate incidents each year; other reports indicate that multiple leaks have resulted in nearly 4.5 million gallons of oil being spilled into the Niger Delta in the last year alone.
Huffington Post June 2, 2010