Like a couple of my sisters have already mentioned, Delta Zeta's national philanthropy is Gallaudet University for the Hearing and Speech Impaired, and we do have a chapter there.
I also know that the ADPi chapter on my campus had a very involved hearing-impaired sister who pledged the same year I did. Her disability never stopped her from doing things she loved.
She was a very intelligent woman with a wonderful GPA, and she competed in beauty pageants during her college years. If I remember correctly, she was a representative in the Miss Georgia pageant in the early 90's, and she may have even won that title. It's been so long ago now that I can't remember the outcome of the pageant that year. Regardless of whether she won or not, she was a definite asset to her chapter and the Greek system in general!