(1) The policies and goals set forth in SEPA are supplementary to existing agency authority.

(2) Agencies shall to the fullest extent possible:

(a) Interpret and administer the policies, regulations, and laws of the state of Washington in accordance with the policies set forth in SEPA and these rules.

(b) Find ways to make the SEPA process more useful to decision makers and the public; promote certainty regarding the requirements of the act; reduce paperwork and the accumulation of extraneous background data; and emphasize important environmental impacts and alternatives.

(c) Prepare environmental documents that are concise, clear, and to the point, and are supported by evidence that the necessary environmental analyses have been made.

(d) Initiate the SEPA process early in conjunction with other agency operations to avoid delay and duplication.

(e) Integrate the requirements of SEPA with existing agency planning and licensing procedures and practices, so that such procedures run concurrently rather than consecutively.

(f) Encourage public involvement in decisions that significantly affect environmental quality.

(g) Identify, evaluate, and require or implement, where required by the act and these rules, reasonable alternatives that would mitigate adverse effects of proposed actions on the environment.