The National Environmental Policy Act was signed into law by President Nixon in 1969. The Act declares a national policy to "...encourage productive and enjoyable harmony between man and his environment; to promote efforts which will prevent or eliminate damage to the environment and biosphere and stimulate the health and welfare of man; [and] to enrich the understanding of the ecological systems and natural resources important to the Nation...".
NEPA imposes no requirements on the public. Rather, it directs Federal agencies to "utilize a systematic, interdisciplinary approach ... in planning and decision making which may have an impact on man's environment", to insure that “ environmental amenities and values ... be given appropriate consideration in decision making along with economic and technical considerations", and to "study, develop, and describe appropriate alternatives to recommended courses of action...". This mandate applies to all "Federal actions". As a result, NEPA affects virtually all decisions regarding the use of the public lands.