In 2002, the Department of Transportation (DOT) released the Pipeline Security Information Circular. The Circular established recommendations for improving security at pipeline facilities across the country, including to: (1) identify critical pipeline facilities; (2) develop security plans for critical facilities that is equivalent to security plans endorsed by the relevant trade association; (3) implement the plans as soon as possible; and (4) conduct annual reviews of the security plan and make changes as the need arises. Because the Circular was released before Congress passed legislation on pipeline security, the recommendations it outlined were voluntary.
In 2007, Congress addressed pipeline security in the Implementing Recommendations of the 9/11 Commission Act of 2007, instructing DHS to take the following actions:
In August 2008, pursuant to the Act, the Department of Homeland Security (DHS) and Transportation Security Administration (TSA) published a notice in the Federal Register seeking information from 125 pipeline operators in order to determine the 100 most critical pipeline facilities. Then, in July 2009, DHS/TSA published another notice seeking comments in anticipation of updating the Circular. However, rather than updating the Circular, in December 2010, TSA published Pipeline Security Guidelines which supersede the Circular. TSA then published Updated Pipeline Security Guidelines in April 2011 along with Pipeline Security Smart Practice Observations in September 2011. In March 2018, TSA published the most recent version of its Pipeline Security Guidelines.