The Rapid City-Pennington County Emergency Management Office operates under a Joint Rapid City-Pennington County Agreement. The Multi-Hazard Emergency Operations Plan is written as guidance for emergency/disaster operations in Rapid City, Wall, New Underwood. Box Elder, Hill City, Keystone, and the remainder of Pennington County.

Pennington County has a history of disasters, such as forest fires, structural fires, flash floods, tornadoes, blizzards and drought. These disasters have caused millions of dollars in property damage and the loss of several hundred lives. Pennington County is also vulnerable to many types of technological disasters. The transportation systems in the County (highways, air, pipelines. utilities, rail) could have serious emergencies escalate into major disasters if improperly handled. Hazardous materials (HazMat) spills, terrorist activities, military accidents, or dam failure may also cause emergencies.

A hazard analysis study of Pennington County was conducted and is on file in the Emergency Management Office. A study summary shows that hazard susceptibility in Pennington County can be grouped by the frequency of possible occurrence. Within each frequency, the hazards are listed in descending order based on the potential affect on population.

• Once or more a year: Wildfire, Highway HazMat Incident, Flood/Flash Flood
• Once every five years: Tornado, Severe Winter Storm, Fixed Facility HazMat Incident, Urban Fire, Pipeline HazMat Incident
• Once every 10 years: Power Failure, Drought, Civil Disorder, Highway Radiological Incident
• Once every 50 years: Dam Failure, Earthquake, Rail HazMat Incident, Air Transportation Incident, Landslide
• A hazard, but has not occurred: Nuclear Attack, Aquifer Vulnerability, Subsidence