Not all of us are like the founder of LifeLock by hanging up billboards of our social security numbers giving people access to our most private number. The bottom line is that most people don't want their social security number posted in public. It leaves you more susceptible to identity theft and can leave you with a bad credit rating, at no fault to your spending habits.
A Google Webmasters Help thread has one person very eager to have Google remove his social security number from a third-party web page. This person supposedly ticked someone off, who then got back at him by posting his information, including social security number on a web page. Google indexed the web page and he wants it removed.
Clearly, in this case, you cannot plead with the webmaster to remove the page. You may be able to contact the hosting company and ask them to remove the page. But you can use the Google Removal Tool to ask Google to remove it from their index. Googler, Jonathan Simon said:
I agree with LuSEOfer's suggestion of contacting the site owners to get your information removed at the source. It may not help if the site owner is the same person as the person who posted your information but it's worth a try. Most reputable site owners don't want this sort of information on their site.
Forum discussion at Google Webmasters Help.