In the selection for employment of the professional staff as a whole, the Director shall be guided by the following criteria:

(a) Outstanding character and competence—both personal and professional.

(b) Spread and balance of training and experience in the several relevant professions—ecology; economics; economic geography; engineering; fish and wildlife biology; forestry; hydrology; irrigation; landscape architecture; law; political science; recreation; sanitary engineering; soil conservation; urban and other land planning; etc.

(c) Diversity of prior identification and experience, both planning and operating in Washington and in the field; including personnel with prior identification and experience with Federal, State, or local government, private enterprise, or university teaching and research.