A major new independent scientific assessment, carried out by the United Nations Environment Programme (UNEP), shows that pollution from over 50 years of oil operations in the region has penetrated further and deeper than many may have supposed. The assessment has been unprecedented. Over a 14-month period, the UNEP team examined more than 200 locations, surveyed 122 kilometres of pipeline rights of way, reviewed more than 5,000 medical records and engaged over 23,000 people at local community meetings. The environmental restoration of Ogoniland could prove to be the world's most wide-ranging and long term oil clean-up exercise ever undertaken if contaminated drinking water, land, creeks and important ecosystems such as mangroves are to be brought back to full, productive health. The report key findings are alarming both in terms of human health protection and environmental protection: some areas, which appear unaffected at the surface, are in reality severely contaminated underground; at least 10 Ogoni communities where drinking contaminated water; control and maintenance of oilfield infrastructure in Ogoniland has been and remains inadequate; the impact of oil on mangrove vegetation has been disastrous. The report recommends direct actions in order to address the Niger Delta contamination by oil and warns that the restoration of the area could take up years.