The evolution of regulatory codes, standards, and practices has increased the need for risk modelling to become data-driven to support more informed decision making. One Call1 information is a source of regular insight into activities along the pipeline right of way that could influence excavation damage prediction algorithms. However, the treatment of One Call data related to threat impact is challenging. Advances in technology, analysis techniques, and quantity of data available and accessible now afford for data integration and the observation of meaningful outcomes regarding relevance of One Call data to leak and repairs based on related design and geospatial data elements. This paper will review the current challenges faced in excavation damage modelling used in pipeline risk algorithms, present alternatives for increasing granularity and value in the risk assessment, discuss the uncertainties involved with leveraging these alternatives, and share remaining work required to improve the accuracy, prediction, and reliability of excavation damage prediction algorithms.
Excavation damage is a recognized threat to pipeline integrity when external human activity contacts the pipe body creating a change in shape (i.e., dent, ovality) or wall thickness (i.e., gouge). Industry standards provide similar, but slightly different variations on this definition:
• ASME2 B31.8S (1) Section A-8: "Third party damage is defined in this context as third-party inflicted damage with immediate failure, vandalism, and previously damage pipe."
• API3 RP 1160 (2) Annex A.9: "This threat arises from excavation, drilling, boring, farming, or other soil moving or removal activities where the mechanical equipment being used comes in contact with a buried pipeline causing it to leak or rupture."
• CSA4 Z662:19 (3) Annex H: "Third party: Inadvertent external interference by a person or group of people other than the operating company and its employees and contractors."
Excavation damage can be generalized to include damage by the operator (first-party damage), damage by a contractor hired by the operator (second-party damage), or damage by another unrelated party (third-party). Excavation damage can result in immediate failure or in delayed failure and can cover a broad category of activities, including drilling, boring, auguring, grading, grinding, hand digging, milling, pile driving, trenching, and excavation via mechanical equipment, among others (4). B31.8S classifies the threat of excavation damage as time-independent. The damage mechanism doesn't rely on a time component (i.e., features become worse over time), as opposed to threats such as corrosion or cracking, where the threat has the potential to become more prevalent over time.
