Can you apply to two different grad programs at the same school Social Work and Creative Writing specifically Or will this hinder your chances of getting accepted to either?

It is possible, however it is not typically the best idea. In an effort to take giant steps, many individuals wind up moving backwards. Personally I believe you should list your priorities and focus on a primary goal. Once finished, you can always go on to tackle a new one. Still, this is just a personal opinion, but it is based on experience and observation over my 26 years in higher education.