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Emergency Planning Zones

A keystone of any plant's preplanned protective action strategy involves two emergency planning zones (EPZs) around the plant. The EPZ's size and shape vary for each plant due to detailed consideration of the specific site conditions, unique geographical features of the area, and demographic information. EPZ-specific strategies provide a strong starting point for implementing additional measures beyond the planning zone, if extremely unlikely events unfold.

Emergency Planning Zones

The two EPZs are described as follows:

Plume Exposure Pathway EPZ

The first EPZ is a plume exposure pathway extending about 10 miles in radius around the reactor site. Protective action plans within this area are designed to avoid or reduce dose from potential exposures such as inhaling radioactive particles. These actions include sheltering, evacuation, and the use of potassium iodide pills where appropriate.

Typical 10-Mile Plume Exposure Pathway EPZ Map

Figure 1 depicts a typical 10-mile plume exposure pathway EPZ map. The center of the map is the location of the commercial nuclear power plant reactor building. Concentric circles of 2, 5, and 10 miles have been drawn and divided into triangular sectors identified by letters from A to R. Municipalities identified to be within the 10-mile EPZ have been assigned numbers from 1 to 24. The triangular sectors provide a method of identifying what municipalities are affected by the radioactive plume as it travels.

Ingestion Exposure Pathway EPZ

The second EPZ is an ingestion exposure pathway extending about 50 miles in radius around the reactor site. Protective action plans for this area are designed to avoid or reduce dose from eating or drinking radioactive materials. These actions include a ban of contaminated food and water.

Page Last Reviewed/Updated Wednesday, August 28, 2024