Section 4(c) of the Wilderness Act provides the basis for the concepts of “minimum requirement” and “minimum tool.” These concepts apply to agency administrative actions in wilderness, including actions undertaken by non-agency entities with authorization through a permit issued by the managing agency. Examples of administrative actions are trail construction and maintenance, wildlife management, and fire management activities. Examples of agency-authorized activities requiring a permit are scientific research, management of livestock grazing, and commercial outfitting and guiding. Together, the concepts of minimum requirement and minimum tool are used to determine the appropriateness of administrative actions in Wilderness.

Section 4(c) prohibits a variety of specific actions in wilderness because their presence, however temporary, is contrary to the meaning of Wilderness character:

PROHIBITION OF CERTAIN USES. Except as specifically provided for in this Act, and subject to existing private rights, there shall be no commercial enterprise and no permanent road within any wilderness area designated by this Act and except as necessary to meet minimum requirements for the administration of the area for the purpose of this Act (including measures required in emergencies involving the health and safety of persons within the area), there shall be no temporary road, no use of motor vehicles, motorized equipment or motorboats, no landing of aircraft, no other form of mechanical transport, and no structure or installation within any such area.

Section 4(c) explicitly prohibits two things in Wilderness, and also prohibits a number of other specific activities but makes two narrow exceptions for when these activities may be allowed. The two explicitly prohibited activities are commercial enterprise and permanent roads. The only exception to this prohibition is if there are prior existing rights that allow for these uses, such as a legal right-of-way.
The other generally prohibited activities in Sec. 4(c) include landing of aircraft, temporary roads, use of motor vehicles or mechanized transport, motorboats, motorized equipment, and placement of structures or installations. The Wilderness Act provides two very narrow exceptions for these generally prohibited activities, as described in the two steps discussed below.

The minimum requirement concept does not apply to the general public’s use of wilderness because the general public has no authority to engage in any of the prohibited activities listed in Sec. 4(c) of the Act.

Applying the minimum requirement and minimum tool concepts to a proposed management action is a two-step process.

First Step: Make a Minimum Requirement Determination

To assess the appropriateness of any proposed management action in wilderness, first determine if the proposal includes any of the prohibited activities that are listed in section 4(c) of the Wilderness Act. If any of the Sec. 4(c) prohibited activities are part of the proposal, then the first step is to determine if they are justified based on the two narrow exceptions provided in Sec. 4(c) of the Wilderness Act.

Begin by asking the following two questions:

(1) Does the proposal involve an emergency affecting the health and safety of humans within the wilderness? If so, then the action may meet the minimum requirement test according to law.
This first narrow exception allows agencies to undertake the generally prohibited actions if they are required in emergencies involving the health or safety of persons within the area. This does not mean the agencies can engage in prohibited activities such as use of motor vehicles or motorized equipment to carry out preventive safety measures. The Act is clear that there must be an existing emergency. The agencies also cannot engage in generally prohibited activities in Wilderness to protect people or communities that are located outside the wilderness. It must be an emergency involving people who are inside the Wilderness.

If the management proposal does not involve a health or safety emergency, then move to the second question:

(2) Is the proposed management action necessary to meet minimum requirements for preserving Wilderness character and protecting an enduring resource of wilderness?

This question hinges on whether undertaking the proposed action is the minimum requirement necessary in order to adequately administer and protect the wilderness resource. Asking the following questions will held determine if a project is necessary and the minimum required to protect the Wilderness.

What is the intent of the proposed action? Is the proposal aimed at carrying out an action or activity that is unrelated to protection of Wilderness character and the Wilderness resource? For example, is the project aimed at increasing game populations for sportsmen? If so, the intent to manipulate natural processes in Wilderness is inappropriate. Wilderness, by statutory definition, is to remain untrammeled. Although hunting may be allowed, it does not justify undertaking incompatible activities in Wilderness that are contrary to preserving Wilderness character.

To assist in determining the intent of an action, it is helpful to ask who proposed it. If the answer is anyone other than the wilderness management agency, then the project is probably not necessary for protection of the wilderness. No entity other than the wilderness management agency has a legal obligation to preserve the wilderness resource, so the intent of projects proposed by other entities are for other unrelated purposes. Outside entities that often propose projects in wilderness include the states, counties, utility companies, scientific researchers, historic preservation societies, and commercial services such as outfitting or scenic air tour companies. Even if a project proposed by one of these other entities appears to provide some peripheral benefit to Wilderness, the key point is it clearly is not necessary for protection of the Wilderness resource and therefore cannot justify use of the generally prohibited activities inside Wilderness.

S Is the proposed action the minimum required? If undertaking an action is necessary to protect the Wilderness resource, then the next question to ask is whether the specific action proposed is the minimum required action to achieve the Wilderness protection goal. Are there other alternative actions that would accomplish the same goals but be far less intrusive in Wilderness?
If the minimum requirement analysis demonstrates that management action is necessary and a particular action is the minimum required to achieve good stewardship of the Wilderness resource, then the proposal passes the minimum requirement test. The next step is to apply the minimum tool test.

Second Step: Make a Minimum Tool Determination

What if the project does meet the minimum requirement test? This still does not mean that the prohibited actions such as use of aircraft or motor vehicles or chainsaws are the appropriate tools for accomplishing the project’s wilderness protection goals.

S What is the minimum tool to accomplish the project? Perform a “minimum tool” analysis by asking yourself if it is possible to accomplish the project without using any of the prohibited activities listed in Section 4(c) of the Wilderness Act? If it is not feasible to implement the “minimum required” action without relying on one or more of the generally prohibited activities in Section 4(c) then the prohibited activities pass the minimum tool test because they are the minimum tool necessary to achieve the wilderness protection goal of the project. Feasibility must be determined by what is physically possible, and not be premised on efficiency, convenience, or cost. Violating the spirit of the Wilderness act by using motorized or mechanized equipment, aircraft, etc. in Wilderness should occur only very rarely, if at all. Often times it is best to review the minimum requirement analysis again to reconsider whether the project is truly necessary and required.

In a nutshell, the agency can only approve prohibited actions in Wilderness for administrative purposes if the overall project is the minimum requirement necessary for administration of the area as Wilderness, or in a human health and safety emergency involving people located within the wilderness, and if the prohibited use is the minimum tool for accomplishing the project.