On May 5, 2011 the U.S. Senate Committee on Commerce, Science, and Transportation held its mark-up on S. 275, the Pipeline Safety Improvement Act. The bill, along with three ammendments that were previously been agreed to by the Majority and Minority, passed by a unanimous voice vote. Senator Boxer’s amendment required operators to consider seismicity in high consequence areas (HCAs); Senator’s Udall's amendment required operators to consider maintaining records of inspections conducted outside of HCAs; and Senator Thune’s amendment included language on enforcement due process. The pipeline safety bill and the approved amendments are listed below: