Automated geographical grouping of volunteers and PINs

[TheRealAlexV]

I would like to figure out some sort of way of geographically grouping people by their area codes and/or zip codes. Spoke stores both.

[mcverter]

Here you would want to use zip codes, because cell numbers have no necessary relationship to location.
For the most proximate people you would want to just use numeric ranges of the zip codes.
If you wanted to check against municipality and state boundaries, those can be loaded from somewhere and a tables can be created to correlate zip codes with these boundaries

[mcverter]

What is the best way to group volunteers? In a campaign? Are there other ways of filtering users?