The Mapping Application for Response, Planning, and Local Operational Tasks (MARPLOT) is the mapping program for the CAMEO software suite. MARPLOT is widely used to plan for and respond to chemical/hazardous materials emergencies.
MARPLOT’s easy-to-use GIS interface allows one to add objects to a map, as well as view and edit data associated with the objects. One can choose between several background basemap images and can customize the map further with annotations and online layers from Web Mapping Services. One can also interact with the map in other ways, such as getting population estimates within an area.
MARPLOT can be run by itself as a general mapping program. It can also be used interactively with programs in the CAMEO suite to display ALOHA threat zone estimates on the map or to link map objects to database records in CAMEOfm (database and information management tool).
For further information or download information go to epa.gov/cameo/marplot-software.
Source: Developed by the U.S. Environmental Protection Agency (EPA)
Reviewed for relevancy: 2026