Who is described as one who can identify existing and predictable hazards and has the authority to eliminate them?

The description given in the question aligns perfectly with the role of a competent person. A competent person is typically defined as an individual who is knowledgeable about the safety standards and regulations pertinent to the work environment. This person possesses the necessary experience, education, and training to recognize existing hazards and can foresee potential hazards in the workplace.

In addition, the competent person has the authority to take corrective measures to eliminate these hazards, which is crucial in ensuring a safe working environment. This role is central in various fields, particularly in construction and industrial operations, where safety is paramount. The ability to identify risks and implement safety measures proactively constitutes the primary responsibility of a competent person, distinguishing them significantly from other roles listed.

The other options, while related to safety and management, do not encompass the specific authority and responsibility that a competent person has regarding identifying and eliminating hazards. For instance, safety officers typically enforce safety policies but may not have direct authority to eliminate hazards; site supervisors manage daily operations on-site but aren't always designated as competent persons; incident commanders focus on managing responses to emergencies and incidents rather than ongoing hazard identification.