Environmental impact statements (EISs) are documents that provide an overview of the environmental consequences of proposed federal and state decisions. In order to comply with the NEPA report, every federal agency and state government may have to prepare an EIS for any project that would have a significant effect on the environment. 

The NEPA process was designed to allow public input into federal decision-making about projects that could potentially impact the environment. The law requires agencies to identify all potential environmental impacts of a project, analyze those impacts, and consider alternative actions that would avoid or lessen those impacts. This analysis can be difficult, time-consuming, and costly, but it is essential for protecting our environment and public health.

Environmental impact statements (EISs) are a formal tool used by federal, state and local governments to assess the environmental impacts of proposed projects. An EIS is composed of two parts: an environmental assessment (EA) and a supplemental environmental report (SER). The EA evaluates the environmental impacts of a proposed project, while the SER provides additional information and analysis on specific issues. 

An EIS must be completed whenever significant environmental impacts are expected, including when a project would affect federally listed threatened or endangered species or when it would result in significant changes in air quality. To ensure that all interested parties have an opportunity to comment on an EIS, the Obama administration has issued guidance requiring agencies to make public all draft versions of their EISs, as well as final documents after public input has been received.