Previously, all LLW was sent to South Carolina, Utah or Washington. Federal law requires all states to be part of regional compacts. The compact concept is based on one or more states in the group acting as a host state. For many years there was considerable delay in states coming to an agreement. As a result, there was little progress in the actual construction of waste storage facilities. Most LLW is stored on site in buildings designed to accommodate at least five years of storage.