Greetings all,
Just to make sure Im clear on what is happening: You have a page with a list of locations and a form to update it (if needed) and currently when you hit the refresh button it asks you if you would like to repost the data that was just sent... sound about right?
If so this is most definitely a HTML issue. I would suggest having another button on the page that when hit will simply hit the current URL, this assumes that you have no configuration params in the URL or that you can easily recreate them (you mentioned the form has a post method), my suggestion is to use JavaScript for this. That way you are not triggering the reposting of your form by hitting the browser refresh button.
Just a thought, Hope that helps.