(1) The agency shall prepare an EA, regardless of its length or the depth of analysis, in a manner which utilizes an interdisciplinary approach. The agency may initiate a process to determine the scope of issues to be addressed in an EA. Whenever the agency elects to initiate this process, it shall follow the procedures contained in ARM 12.2.434.

(2) For a routine action with limited environmental impact, the contents of an EA may be reflected on a standard checklist format. At the other extreme, whenever an action is one that might normally require an EIS, but effects that otherwise might be deemed significant are mitigated in project design or by controls imposed by the agency, the analysis, format, and content must all be more substantial. The agency shall prepare the evaluations and present the information described in section (3) as applicable and in a level of detail appropriate to the following considerations:

(a) the complexity of the proposed action;

(b) the environmental sensitivity of the area affected by the proposed action;

(c) the degree of uncertainty that the proposed action will have a significant impact on the quality of the human environment;

(d) the need for and complexity of mitigation required to avoid the presence of significant impacts.

(3) To the degree required in (2) above, an EA must include:

(a) a description of the proposed action, including maps and graphs;

(b) a description of the benefits and purpose of the proposed action. If the agency prepares a cost/benefit analysis before completion of the EA, the EA must contain the cost/benefit analysis or a reference to it;

(c) a listing of any state, local, or federal agencies that have overlapping or additional jurisdiction or environmental review responsibility for the proposed action and the permits, licenses, and other authorizations required;

(d) an evaluation of the impacts, including cumulative and secondary impacts, on the physical environment. This evaluation may take the form of an environmental checklist and/or, as appropriate, a narrative containing more detailed analysis of topics and impacts that are potentially significant, including, where appropriate: terrestrial and aquatic life and habitats; water quality, quantity, and distribution; geology; soil quality, stability, and moisture; vegetation cover, quantity and quality; aesthetics; air quality; unique, endangered, fragile, or limited environmental resources; historical and archaeological sites; and demands on environmental resources of land, water, air and energy;

(e) an evaluation of the impacts, including cumulative and secondary impacts, on the human population in the area to be affected by the proposed action. This evaluation may take the form of an environmental checklist and/or, as appropriate, a narrative containing more detailed analysis of topics and impacts that are potentially significant, including where appropriate, social structures and mores; cultural uniqueness and diversity; access to and quality of recreational and wilderness activities; local and state tax base and tax revenues; agricultural or industrial production; human health; quantity and distribution of employment; distribution and density of population and housing; demands for government services; industrial and commercial activity; locally adopted environmental plans and goals; and other appropriate social and economic circumstances;

(f) a description and analysis of reasonable alternatives to a proposed action whenever alternatives are reasonably available and prudent to consider and a discussion of how the alternative would be implemented;

(g) a listing and appropriate evaluation of mitigation, stipulations, and other controls enforceable by the agency or another government agency:

(h) a listing of other agencies or groups that have been contacted or have contributed information:

(i) the names of persons responsible for preparation of the EA; and

(j) a finding on the need for an EIS and, if appropriate, an explanation of the reasons for preparing the EA. If an EIS is not required, the EA must describe the reasons the EA is an appropriate level of analysis.