Prior to July 1, 1991, the director shall issue guidelines to assist government agencies in the preparation of environmental effects reports in accordance with this chapter, including, but not limited to, provisions for:

(1) Criteria for determining if a proposed governmental action may significantly adversely affect the quality of the environment;

(2) Comment upon the proposed governmental action by public and private organizations and individuals;

(3) The possibility of the preparation of single-program environmental effects reports if a series of governmental actions taken individually are of minimal adverse significance on the environment but the cumulative effect of the proposed government actions on the environment is significantly adverse or if a series of proposed government actions are related either geographically or as logical parts in a chain of contemplated actions; and

(4) The possibility of the preparation of modified environmental effects reports on remaining decisions significantly adversely affecting the quality of the environment that are parts of actions begun before but not completed before July 1, 1991.