OPH field staff assist park units with the identification and reduction or elimination of public health hazards through comprehensive on-site evaluations and consultations that focus on four priorities.

• Drinking Water - The NPS owns and operates approximately 1,300 drinking water systems. On-site visits are used to evaluate the degree of control that park units have over critical drinking water safety issues and to provide guidance about compliance with applicable regulatory requirements.
• Wastewater - The NPS operates a wide variety of wastewater facilities, ranging from pit privies to advanced wastewater treatment plants. OPH professionals conduct plan reviews and evaluate the operation and maintenance of these systems. Compliance with primacy agency regulations is also evaluated and communicated to park unit managers.
• Food Safety - Food service facilities of all types, both permanent and temporary, are evaluated by OPH professionals. Consultation is provided to concessioners in risk reduction and strategies for reducing the potential of foodborne illness, chemical poisoning, or accidental injury.
• Recreational Waters - Bathing Beaches, Swimming Pools and Spas, both permanent and seasonal, are evaluated by OPH professionals. Consultation is provided to concessioners in risk reduction and strategies for reducing the potential of waterborne illness, chemical poisoning, or accidental injury.