An operator must assess the integrity of the line pipe in each covered segment by applying one or more of the following methods depending on the threats to which the covered segment is susceptible. An operator must select the method or methods best suited to address the threats identified to the covered segment. (See section 255.917 of this Part.)

An operator must prioritize the covered pipeline segments for the baseline assessment according to a risk analysis that considers the potential threats to each covered segment. The risk analysis must comply with the requirements in section 255.917 of this Part.

In choosing an assessment method for the baseline assessment of each covered segment, an operator must take the actions required in section 255.917(e) of this Part to address particular threats that it has identified.

An operator must prioritize all the covered segments for assessment in accordance with section 255.917(c) of this Part and subdivision (b) of this section. An operator must assess at least 50 percent of the covered segments beginning with the highest risk segments, by December 17, 2007. An operator must complete the baseline assessment of all covered segments by December 17, 2012.

An operator may use a prior integrity assessment conducted before December 17, 2002 as a baseline assessment for the covered segment, if the integrity assessment meets the baseline requirements in this Part and subsequent remedial actions to address the conditions listed in section 255.933 of this Part have been carried out. In addition, if an operator uses this prior assessment as its baseline assessment, the operator must reassess the line pipe in the covered segment according to the requirements of sections 255.937 and 255.939 of this Part.

When an operator identifies a new high consequence area (see section 255.905 of this Part), an operator must complete the baseline assessment of the line pipe in the newly identified high consequence area within 10 years from the date the area is identified.

An operator must complete the baseline assessment of a newly installed segment of pipe covered by this Part within 10 years from the date the pipe is installed. An operator may conduct a pressure test in accordance with paragraph (a)(2) of this section, to satisfy the requirement for a baseline assessment.

If the threat analysis required in section 255.917(d) of this Part on a plastic transmission pipeline indicates that a covered segment is susceptible to failure from causes other than third-party damage, an operator must conduct a baseline assessment of the segment in accordance with the requirements of this section and of section 255.917 of this Part. The operator must justify the use of an alternative assessment method that will address the identified threats to the covered segment.