(This measure has not been amended since it was introduced. The summary has been expanded because action occurred on the measure.) Plum Island Preservation Act (Sec. 3) This bill requires the Government Accountability Office (GAO) to submit to Congress a report on alternatives for the final disposition of Plum Island, New York, including transfer to another government or nonprofit entity for education, research, or conservation purposes. This report must contain, for each alternative, an analysis of: the effect it would have on the island's resources; remediation responsibilities under it; legislation necessary to implement it; possible implications and issues of implementing it; potential costs, including costs of the transition, hazard mitigation, and cleanup of property that would be incurred by a recipient; and potential revenue. (Sec. 4) No action, including any pre-sale marketing activity, may be taken to carry out the requirement under current law for the General Services Administration to sell the property and assets that support Plum Island operations until at least 180 days after such report has been submitted.