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Environmental Impact of the Oil Industry with and without the oil and gas industry, (not, as is sometimes the case, arising from an insufficient understanding of the environment in terms of before and after).

15.1.3 EIA IS NOT LIMITED TO 'NATURAL' ECOLOGICAL CONDITIONS

Although this should now be obvious to the reader, it is remarkable how often EIA confines itself only to ecological conditions as if they are something separate from human ecosystems. The environment upon which the impact of the oil industry is being assessed is the human environment in all its manifestations. There are four layers of the human environment upon which human activities have an impact: each needs to be understood in order to be able to assess the significance of the impact; and, the impact on one layer can only be fully understood if the underlying layer is pre-conditionally understood. These layers, with an example, are shown below. 160