I can almost guarantee they are referring to legal descriptions using the Public Land Survey System (PLSS).
Do they mention township or range?
The Wisconsin DNR uses the PLSS to describe fire locations. I also believe Minnesota does.
For a fire location near me the location would be given over the radio as: Northwest quarter, Southeast quarter, Section 24, Township 44 North, Range 10 West. This could also be abbreviated as: Northwest, Southeast, 24, 44, 10, leaving off the extra words if the approximate location is known by the dispatcher.
Topographic maps have the PLSS grid drawn on them. Plat books are a good source. You can also drawn your own PLSS grid on any map of your choice fairly easily. A quick search showed a few ways to use PLSS in Google Earth if you wanted to use that.