That is an error in the programmers'/developers' code.

For instance if you navigate to: http://www.imywebsite.gov/sectionA/sectionB/section/page/
And then add a slash: http://www.imywebsite.gov/sectionA/sectionB//section/page/

The exact same page will load in most modern browsers.  This is something you want to fix.  If you have the double slash it could confuse Google's web crawlers and make them think there is 2 versions of the page.