It appears that this event occurred at the Oregon Women's Correctional Center during October 1988. Both a hunger strike and sit-in occurred to draw attention to the problems the prisoners were facing, including over-crowding, educational discrimination, and more. According to a newspaper account (see citation below), the Oregon chapter of the ACLU was interested in investigating the prisoners' claims. Perhaps they could also be of assistance to you. Their contact information is:
ACLU of Oregon
Executive Director: David Fidanque
P.O. Box 40585
Portland, OR 97240-0585
Here is the citation for the article I located on the sit-in: Ames, Sarah B. "Protests put Women's Prison in Spotlight" Oregonian October 31, 1988, pB2.
The article also notes that the Task Force on Corrections Planning issued a report in the summer of 1988 that indicated there was discrimination present in educational and work programs, namely that women did not have equal opportunity. I believe the report to which the article refers is this one:
A strategic corrections plan for Oregon: restoring the balance.
Oregon. Governor's Task Force on Corrections Planning.
Salem: Governor's Task Force on Corrections Planning, 1988
The same task force two years later issued a report that may also be of interest to you:
Hopefully you can obtain the article and reports via interlibrary loan from your local library. I hope this information will be helpful to you.