How do you go about the Impact assessment? The World Bank in ist policy, the OECD in ist Common approaches and in ist Guidelines for Multinational Companies have clarified their expectations.
The EU has passed a suite of regulations and now follows up with ist EU Action Plan where it also deals with impact assessments.
In general, we are talking about assessing risks and impacts for the following areas.
More information is available in their PDF, which can be downloaded here