Geotechnical monitoring based on optical fiber sensor technology has been used over more than a decade to detect hazards than can affect the integrity of pipelines. In particular when these sensors are implemented in the form of distributed temperature and strain sensors, respectively known as DTS and DSS, they provide information about hazard location and spatial extension. In addition, these sensors can capture the speed at which the event developing in particular when implemented as a permanent monitoring solution. So far these sensors were implemented as part of an alarming system detecting events such as landslides, erosion and subsidence. The current work aims at presenting simple method to extract additional information about the hazard such as the amplitude of the soil displacement in the case of landslides and subsidence or dirt cover for erosion. Estimation of stress in soil is also discussed based on the cable strain-stress relation obtained from the sensing cable qualification. The approach is validated by academic works conducted in parallel of the technology development. The method use is then illustrated by its application to field data collected from several events occurred over the past 10 years.

Many pipelines are built in regions affected by harsh environmental conditions where changes in soil texture between winter and summer increase the likelihood of risks. Pipeline routes also cross the mountains that are characterized by steep slopes and unstable soils as in the Andes and along the coastal range of Brazil. In other cases, these pipelines are laid in remote areas with significant seismic activity or exposure to permafrost. Depending on weather conditions and location, visual inspection is difficult or even impossible and therefore remote sensing solutions for pipes offer significant advantages over conventional inspection techniques. Optical fibers can help solve these challenges. Optical fiber based geotechnical and structural monitoring use distributed measurement of strain and temperature thanks to the sensitivity of Brillouin scattering to mechanical and thermal stresses. The analysis of scattering combined with a time domain technique allows the measurement of strain and temperature profiles. Temperature measurement is carried out to control soil erosion or dune migration through event quantification and spatial location. Direct measurement of strain in the soil also improves the detection of environmental hazards. As an example the technology can pinpoint the early signs of landslide. In some cases, pipe actual deformation must be monitored such as in case of active tectonic fault crossing. Pipe deformation monitoring operation is achieved by the measurement of distributed strain along fiber sensors attached to the structure. This paper comprehensively reviews over 10 years of continuous development from technology qualification and validation to its implementation in real cases as well as its successful continuous operation. Case studies present pipeline monitoring in Arctic and Siberian environment as well as in the Andes. They illustrate how the technology is used and demonstrate proof of early detection and location of events such as erosion, landslide, subsidence and pipe deformation.

The 408 km × 34" PERULNG pipeline (operated by Hunt LNG Operating Company) is monitored in its first 62 km by a geotechnical fiber optic cable, since these first 62 km are exposed to major geohazard threats such as landslides, large river crossings, high slopes, bofedales, etc. The fiber optic cable geotechnical monitoring relies on the measurement of strain and temperature in the pipeline right-of-way. Due to the continuous and real-time monitoring of the duct, it was possible to detect a tension cracking near KP 25 + 600 as an abnormal temperature change was captured by the temperature sensing cable; also near KP 27 + 900 and KP 34 + 750 unusual cable stresses were detected which announced landslides of the rotational type in both locations. In these three cases, protection decisions could be taken to secure pipeline’s integrity.

Planet Earth has recently witnessed a change in the behavior of climate variables (including temperature, rainfall, etc.), primarily attributed to global warming. This climate change is a threat that is materializing and has affected elements of the infrastructure, ecosystems, and environmental conditions worldwide, as well as the National Development Plans [“Planes Nacionales de Desarrollo”] . The hydrocarbon-transport infrastructure in Colombia has not escaped the effects of climate variability. Therefore, a strategy must be devised to manage the risk and to adapt these systems in the light of potential harmful effects, and also to supplement or improve the mitigation measures for the effects generated by the oil industry through its operations. Climate disturbances lead to an increase in the likelihood of landslides, wildfires, floods, avalanches, and other natural hazards. The major climate changes that have been identified and that may affect hydrocarbon-transfer systems in Colombia are the following ones: • A gradual increase in temperature. • Changes in the patterns and amounts of rainfall. • A rise in sea level. • An increase in the severity and frequency of extreme weather events. The strategy for adapting the hydrocarbon-transport systems in light of climate change focuses primarily on the following points: 1. Acquiring more knowledge about the climatic changes that are expected to occur in Colombia, including the change in the major climatic variables and their georeferencing. 2. Diagnosing the transport systems and their spatial correlation with future climate scenarios. 3. Identifying the industries or elements of the infrastructure that are most vulnerable to the expected climatic changes. 4. Proposing measures that will add strength and/or resilience, so that the elements of the system can resist the effects of climate change, or overcome them within a short period of time, without affecting the Business. 5. Prioritizing the interventions to be performed at sites that are critical to the Business. 6. Monitoring and tracking the climatic variables in order to adjust the susceptibility models in light of the major impacts (e.g., landslides). The primary goal of this paper is to outline the initiative that has been proposed by the Technical Asset Management Bureau [“Gerencia Técnica de Activos”] (GTA) of Ecopetrol’s Office of the Vice President for Transportation and Logistics [“Vicepresidencia de Transporte y Logística”] (VIT Ecopetrol) in order to adapt the currently operating transport systems so that they can deal with climate change, while ensuring their healthful and safe operation, in compliance with the applicable technical legal requirements. Another goal of this paper is to highlight the advances that have been made by the GTA in the procurement, compilation, analysis, and use of climate information and geotechnical data as basic elements of risk management.

To ensure the integrity of pipelines in failure mode Geotechnical, TRANSPETRO and the TBG perform underwater inspections of pipelines in the main crossings of rivers, lakes, dams, canals and permanently flooded areas. The inspections are designed to locate guideline and measure the covering the pipelines from the margins and underwater depth, identify any exposure of the pipelines, map the occurrences of blocks of rock or debris on the channel and evaluate the anthropic influence on stability of the sections inspected. Among the crossings rivers inspected, in the Atibaia V, with approximately 27.3 m in length, was observed a high erosive potential, which resulted in the loss cover of 3 (three) pipelines of crossing river, besides the fiber optic cable. The lengths uncovered resulted in approximately 33.0 m, with suspended pipes, damage in the concrete jacket and presence of blocks of rocks in the channel. The pipeline in the most critical situation went vain of 6.0 m, with gap up to 0,2 m in relation the background. The crossing river was studied with bathymetric survey and designed cover the pipelines with mechanical protection and anti-erosive. The pipes were supported with sacks of granular material, sequentially, the margins and pipelines were protected with geotextile filled with concrete, installed with the help of divers. The working conditions of 4.0 m depth, currents of up to 0.8 m/s, temperature and low visibility waters were challenges overcome during execution, in which the divers took turns in short periods. Due to the characteristics of the bedrock, the blankets went stylized and stitched on the field by the team, with dimensions taken on site. After positioning the blankets in the background began the underwater concreting, which occurred in stages monitored by the volume pumped and divers strategically placed. The crossing river was re-inspected approximately 1 (one) year after their stabilization and was found in good conditions. The occurrence improved the procedures for geotechnical monitoring and treatment of pipelines uncovered in crossings rivers, being who the efficiency and safety of the work performed currently serve as a reference for the design of similar works.

The present work introduces the technology background at the origin of FOPIMS (Fiber Optic Pipeline Integrity Monitoring Systems) with an emphasis on geotechnical monitoring. It shows how temperature sensing can be implemented to control soil erosion or dune migration through event localization and spatial quantification. Arctic pipeline monitoring project illustrates the application of soil erosion detection. Direct measurement of strain in soil also enhances environmental threat detection. Combined with temperature sensing, strain sensing composes the geotechnical monitoring system. Transandean pipeline monitoring examples are presented where the DITEST AIM was implemented for geohazard prevention. These study cases concern new pipeline installation as well as retrofit of existing lines. The technique successfully evidenced early events and allowed preventive measures to be taken. In some applications actual pipeline deformation need to be monitored. Such operation is achieved by measuring distributed strain along sensing cables attached to the structure. We show how such measurements complement the geotechnical measurements. We also describe a real implementation in seismic active area. As a whole, the work focuses on the technique principles, the installation and how the system is being implemented for pipeline preventive maintenance. We intend to present a comprehensive set of design guidelines based on real results and lessons learned from the various projects in what concerns geohazard detection and pipeline deformation monitoring.