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.

Hydrocarbon pipelines are exposed to hazards from natural processes, which may affect their integrity and trigger processes that have consequences on the environment. Among the natural hazards are the effects of the earthquakes, the neotectonic activity, the volcanism, the weathering of soils and rocks, the landslides, the flows or avalanches of mud or debris, the processes related to sediment transport such as the erosion, the scour by streams, the floods and the sloughing due to rains. Those processes are sometimes related to each other, e.g. the earthquakes can produce slides, or movement of geological faults, or soil liquefaction; the rain can trigger landslides and can cause avalanches and mudslides or debris flow; the volcanic eruptions can originate landslides and avalanches, or pyroclastic flows. Human activities can also induce or accelerate “natural” processes that affect the integrity of the pipelines. The strength and stiffness of the pipelines allow them to tolerate the effects of natural hazards for some period of time. The amount of time depends on the strength and deformability, the stress state, the age, the conditions of installation and operation of the pipelines and their geometric arrangement with regard to the hazardous processes. In the programs for pipeline integrity management, the risk is defined as a function that relates the probability of the pipeline rupture and the consequences of the failure. However, some people define risk as the summation of the indicators of probability and consequences, such as a RAM matrix. Others define the risk as the product of the probability of failure times the cost of the consequences, while the overall function used to evaluate the rupture probability of a pipeline facing hazards considered in the ASME b31.8 S standard includes all the elements involved in the failure process. In that standard, for the specific analysis of natural hazards, it is proposed that the function is separated in the two following principal elements: the probability of occurrence of the threatening process (hazard) and the pipeline’s capacity to tolerate it. In this paper a general function is proposed, which is the product of the probability of occurrence of the threatening process, the vulnerability of the pipeline (expressed as the fraction of the potential damage the pipe can undergo), and the consequences of the pipeline failure (represented in the summation of the costs of the spilled product, its collection, the pipeline repair and the damages made by the rupture).

The present paper presents the analysis, carried out by the Ocensa pipeline, against a case of longitudinal or axial landslide to the pipeline in the KM 35 + 690, starting from the identification by inertial tool, the geotechnical characterization and the analysis of Soil-pipe interaction, excavation and stress relief and the techniques used to mitigate the effects of sliding on the pipe.

Pipelines crossing mountainous areas are susceptible to ground movement loading from landslides. Structural analysis of pipeline performance from landslide loads is critical for making decisions on the requirement and timing of intervention activities. Current analytical assessment methodologies for pipelines affected by ground movement tend to assume the landslide as an abrupt boundary from the stable region to moving ground, causing an over conservative estimation of the condition of the pipeline. In-line inspection using inertial mapping tools provides invaluable information to assist in the determination of the current pipeline integrity but does not provide a complete picture because axial loads are not defined. Interpretation of in-line inspection data allows the estimation of a transition zone width between stable and unstable ground, where there is a progressive increase in ground movement. Due allowance for the transition zone can remove conservatisms in the assessment methodology and allow a pipeline integrity plan to be created. This paper investigates the influence of landslide transition zone dimensions on the pipeline response and a methodology is developed for the prediction of the transition zone width. The interaction between the ground and the pipe movement is modelled using finite element analysis techniques. The definition of the transition zone properties provides a more reliable prediction of the pipeline performance and enables the current and future pipe integrity to be established with greater confidence.

The OCENSA pipeline crosses the Valley of the Magdalena river flood on its way to the Caribbean Sea, the area of the valley is commonly inundated during the rainy season on shallow waters that remain flooded swamps. These swamps soils are composed by extremely soft peat with thicknesses greater than 15 meters. In June 2016 started the construction of a highway with an embankment of 6 meters in height which was more than 30 meters away from the OCENSA 30” pipeline, Due to the high compressibility of peat, to construct the road the soil is subjected to a process of consolidation and the height of the embankment was corrected adding more material. In July 29 2016 occurs a failure by load capacity on the ground under the embankment and as a result of this fault a lateral displacement of the adjacent soil producing a horizontal displacement in the pipeline of more than 50 cm. This document shows results from the affectation to the pipe and the measures taken to correct the situation.

The OPASC and the OSPAR are 10″ and 30″ pipelines, respectively, which interconnect the State of Santa Catarina and Paraná, crossing the Serra do Mar, in southern Brazil. In 2003, after conducting slope stabilization works on a point of geotechnical activity, vibrating string gauges were installed to monitor the stress in these pipelines, in addition to geotechnical instruments installed to monitor the slope. These gauges were installed in seven sections, with 3 instruments per section, along a span of 180 meters. Although the geotechnical instrumentation has shown no evidence of movement in the slope, the gauges recorded an increase in stress values in some of the sections within three months from the time of installation, however, they remained stable in their values for the next ten years. In 2013, blind hole tests were performed to determine the stresses in these sections and to verify the proper function of the gauges. The combination of these two measurement techniques, vibrating string gauges and blind hole tests, allowed for the determination of the stress state in sections, over time. From there, equivalent stress could be determined and compared with allowable stresses defined in standards. After the completion of the blind hole test and subsequent backfill, stress rose again at the same rate, returning to the level reached after the initial installation of the strain gauges. To reduce the stress level additional excavations have been made to relieve the stress on the pipeline, followed by backfilling performed in a controlled manner in order for the soil to properly compact, which reduced the stress value over the pipes. The graphs depicting variation over time of stress showed a significant reduction in the level of stress after the backfill. The main conclusions are listed as follows: a) the evolution of stress observed by the extensometers was primarily caused by pipeline settling; b) the vibrating string gauges are functioning properly and provide reliable readings even after ten years of service; c) the blind hole testing performed in conjunction with monitoring by vibrating string gauges can provide approximate values of the full stress state; d) after stress relief, backfilling of the trench must be carried out by compacting the soil beneath the pipe in order to reduce bending stresses due to the weight of the soil; e) backfilling of the trench, when not properly performed, can cause compressive stress in bending, reaching 390 mPa over the next few months.

Long range, distributed fiber optic sensing systems have been an available tool for more than a decade to monitor pipeline subsidence integrity challenges. Effective deployment scenarios are an important decision to be factored into the selection of this monitoring equipment and typologies relative to specific project needs. In an effort to analyze the effectiveness of various fiber optic deployment conditions, a controlled field experiment was conducted. Within this field experiment, a variety of distributed fiber optic sensors and point sensors were deployed in predefined positions. These positions relative to the pipeline were selected to support a range of deployment needs including new construction or retrofitting of existing pipelines. A 16-inch diameter by 60-meter long epoxy coated pipeline that was capable of being pressurized to mimic operating conditions was utilized. This test pipe was installed in a typical trench setting. Conventional point gauges were installed at key locations on the pipeline. Fiber optic sensor cables were installed at key locations providing 14 alternative scenarios in terms of sensitivity, accuracy, and cost. After construction of the test pipeline, real time continuous monitoring via the array of conventional and fiber optic sensors commenced. A deep trench was excavated adjacent and parallel to the central portion of the pipeline which began to induce subsidence in the test pipeline. Continued monitoring of the various sensors produced real time visualization of the evolving subsidence. A comparison of the reaction of the sensors is compiled to provide an intelligent selection criteria for integrity managers in terms of accuracy, deployment, and costs for pipeline subsidence monitoring projects. In addition, further analysis of this sensor data should provide more insight into pipeline/soil interaction models and behaviors.

Technological advances have improved pipeline capacity to accommodate large ground deformation associated with earthquakes, floods, landslides, tunneling, deep excavations, mining, and subsidence. The fabrication of polyvinyl chloride (PVC) piping, for example, can be modified by expanding PVC pipe stock to approximately twice its original diameter, thus causing PVC molecular chains to realign in the circumferential direction. This process yields biaxially oriented polyvinyl chloride (PVCO) pipe with increased circumferential strength, reduced pipe wall thickness, and enhanced cross-sectional flexibility. This paper reports on experiments performed at the Cornell University Large-Scale Lifelines Testing Facility characterizing PVCO pipeline performance in response to large ground deformation. The evaluation was performed on 150-mm (6-in.)-diameter PVCO pipelines with bell-and-spigot joints. The testing procedure included determination of fundamental PVCO material properties, axial joint tension and compression tests, four-point bending tests, and a full-scale fault rupture simulation. The test results show the performance of segmental PVCO pipelines under large ground deformation is strongly influenced by the axial pullout and compressive load capacity of the joints, as well as their ability to accommodate deflection and joint rotation. The PVCO pipeline performance is quantified in terms of its capacity to accommodate horizontal ground strain, and compared with a statistical characterization of lateral ground strains caused by soil liquefaction during the Canterbury earthquake sequence in New Zealand.

Petrobras Transporte S/A – TRANSPETRO – is the largest natural-gas processing company in Brazil and holds the leading position in fuel transportation and logistics in the country. The 14,000-km pipeline network, like other civil transportation infrastructure, crosses a huge variety of geological-geotechnical terrains, including those susceptible to natural hazards. The OSBAT right-of-way, which belongs to TRANSPETRO’s pipeline network, has become the object of study in this paper because some sections along the right-of-way have installed geotechnical instrumentation that indicates creep movements, which have been acting continuously for decades. Due to the importance of the OSBAT pipeline, a bibliographic review to support the development of limits for displacement velocity of slope shearing zones was concluded to assist the department responsible for evaluating when atypical behavior in the historical displacement data occurs. This geotechnical warning, allied with field and in-line inspections, will improve the pipeline risk management program. The limits for inclinometers were established using T-Student statistical analysis from a reading database based on geotechnical field inspections. However, direct correlation with pipe strain was not verified due to small accumulated displacements.

Colombia is a country located in a geographical area with great geological diversity, where every day the effects of climate change increases the probability of the failure of buried pipelines due to the movement of land or the instability associated with them. That is why the use of geometric In Line Inspection (ILI) intelligent tools with the inertial module is important for the diagnosis of structural integrity of pipelines and is associated with an integrity management program due to the geotechnical threats present throughout its path. It decreases maintenance costs due to pump stoppage for unscheduled repairs, anticipating the solution, and mitigating and controlling deformations in the pipeline caused by geotechnical ground displacements. OCENSA-Pipeline Central SA (Colombia) has developed, through its experience, a program to manage integrity by determining the structural expense in specific sections due to displacement of the pipeline caused by ground movement through the use of the Geometric ILI tools and MFL inertial module. This paper specifically presents the use of the tool in decision-making based on OCENSA’s preset study limits for deformations in the elastic range and plastic building material of the pipeline. In 1997 OCENSA was among the first companies in Latin America to use Inertial Geo-positioning technology; today there are sectors which have been inspected with this technology as many as five times, in which pipe displacement of up to 5 meters has been found. The case study presented refers to a geographical point on the route of the pipeline located in the Andes, at the site of the movement known as the “La negra” ravine, near the town of Puente Nacional, where movements of the pipeline associated with geotechnically unstable slope conditions were detected by In line inspection (ILI) Geometric and inertial modules, beginning in 2004. Since that time, integrity management was conducted in order to reduce the chances pipeline failure will materialize in this area of geotechnical instability.

The OCENSA pipeline system crosses a wide range of geological zones, finding different stability problems. Those problems related with landslides are stabilized with different kinds of geotechnical works within the pipeline maintenance programs, but sometimes these problems reach big dimensions making very difficult to stabilize them, so mitigation techniques are necessary in order to guarantee the pipe integrity. A mitigation technique using EPS (Expanded Poly-Styrene) blocks is being used in the OCENSA pipeline system (Colombia) in order to reduce the buried pipe response due to soil displacements during landslide events and in creeping slopes. OCENSA is the first operator in Latin America using this technique. Prior to the use of this technique, numerical modeling studies were done with the support of SOLSIN S.A.S. These studies were focused on determining the viability and effectiveness of the proposed technique. The purpose of the EPS blocks is to constitute a low-density fill with very low Young modulus reducing the soil-pipeline interaction forces. These blocks are located near the landslide limits in both, the stable and un-stable zones in order to reduce the stiffness of the materials around the pipe. These blocks allow the pipe to move beyond the landslide limits, reducing the bending strains. The extension of the EPS backfill is determined by means of the geotechnical investigation of the place in study and using the in-line inspection tools data to determine the length of the pipe affected by the soil movement. In this paper, three case studies are presented in which the proposed mitigation technique effectiveness was proved. In this part, data analyses coming from the in line inspection program was done. The inertial tool data showed that the EPS blocks had a significant effect on the pipe response, reducing the total strains compared with those obtained with a normal backfill. This technique can be used to reduce the frequency of the strain-relief excavations in unstable slopes. That means a cost reduction in the pipe maintenance activities and a more efficient integrity management program.

Incidents associated with geohazards involving oil and gas pipelines can be avoided in most cases if there is an adequate program for monitoring pipelines, rights of way and triggering agents aimed at prevention. Knowledge about how to manage geohazards is currently dispersed in the operators’ experiences, and it is necessary to compile a guide that will facilitate the selection of the appropriate technology for monitoring pipelines, rights of way and triggering agents. This document explains the development of a project of the Regional Association of Oil, Gas and Biofuels Sector Companies in Latin America and the Caribbean – ARPEL, the deliverable of which will be a practical technical guide for companies operating in Latin America and the Caribbean for which geohazards represent one of the greatest risks to the integrity of oil and gas pipelines.

When a buried pipeline is exposed in the middle of a river, the need of a mitigation action immediately arises. Lowering the pipeline by natural flexion is sometimes chosen after competing in magnitude, complexity and cost with other alternatives such as river bank and bed erosion control protections. Although simple in its conceptual design, its implementation requires taking into consideration several factors that can affect its successful outcome in terms of the final position of the pipeline and the remediation measures needed to restore the terrain and environment to its original situation. Five different field cases are presented: Río Colorado, Río Santa María, Río Negro and Río Suquía, all of them located at northern Argentina, and a fifth one placed at the Patagonian desert. For each of them references are made regarding the following issues: reasons for the selection of this option, in or out of service movement operation, depth of burial, design of the lowering curve based on pipe allowable tensions, topographic reference system, ditch design, drainage and stabilization, need for river diversion, lowering equipment, ditch interceptors design, ditch filling and soil compaction procedure, and ROW remediation. Finally, a set of recommendations are included as a way to share this experience and provide a guideline for future works.

The strength and stiffness of the pipelines allow them to tolerate the effects of natural hazards for some period of time. The amount of time depends on the strength and deformability, the stress state, the age, the conditions of installation and operation of the pipeline and their geometric arrangement with regard to the hazardous process. Accordingly, some of the hazards due to weather conditions and external forces would not be time independent. In consequence the designing of monitoring systems to predict the behavior of the pipelines against natural hazards is required in order to carry out the preventive actions which are necessary to avoid failure of the pipes due to the exposition to those hazards. In this paper a method for assessing the transport system vulnerability is developed, a function for risk analysis is proposed (which is determined by the probability of the natural hazard, the pipeline’s vulnerability to the hazard and the consequences of the pipe rupture). The elements that are part of that evaluation are presented and illustrated by means of examples.

In-line inspection by inertial mapping techniques is an essential tool for pipeline operators in areas susceptible to geohazards. The detection of previously unknown movements can provide early warning of the presence of a hazard. Positional change and the nature of the loading process can be monitored using the results of multiple inspections over time. Structural modelling is required to fully evaluate the integrity of the pipeline and whether a failure condition is being approached. Finite element techniques can be used, including the effects of soil-pipe interaction, axial forces and operational loads. This enables the prediction of future performance, based on trends from multiple inspections, so that mitigation or intervention methods are efficiently designed and scheduled. This paper considers some key aspects of the analysis process. The use of ILI mapping data to detect small movements below the tool measurement tolerance is examined. The importance of structural analysis is demonstrated by consideration of the axial force component. The inherent variability of the soil surrounding the pipe and its influence on the load transfer effects is illustrated, together with the issues of significant interaction within the transition zones of landslides or faults.

The bi-national pipeline Loma de la Lata (Argentina)-Talcahuano (Chile) belonging to Gas del Pacifico, crosses the Andes at Latitude 37.1° South (Buta Mallin pass), following the Lileo river valley. In the region, there are large ancient landslides within an area of about 50 km2, which have been attributed to Holocene glaciations and seismic activity. In the winter of 2005, when snow limited the access to the area, it was found a pressure loss, that later was attributed to a landslide in a sector of the south bank of the valley. The adiabatic expansion generated a considerable volume of frozen soil around the pipe. The following summer it was studied the characteristics of the sliding and analyzed different solutions of the affected section. The geotechnical study showed details of the slipped area and its relationships with ancient landslides. It was found by comparative analysis of aerial photographs that an old slide about 1 km 3 was not fully reactivated. The general morphology has remained unchanged at least in the last 50 years, when the oldest aerial photography was taken. As additional verification, it was found that a small set of cascading ponds located in the slipped mass, has remained stable at that time, bearing the influence of the great 1960 Mw = 9.6 Valdivia earthquake. It was identified tension cracks delimiting the slipped area that was a modest portion of the historical landslide. Geotechnical parameters were estimated by back analysis of the land involved and it could establish a model for sliding mass process. A general analysis of long-term stability took into account the influence of distant earthquakes such as the subduction zone, which has a recurrence of about 100 years and other local seismic sources. Prior to define the most appropriate solution, a 250 meters long trench was dug preventively releasing the pipeline from the terrain to avoid new deformations. Among the solutions considered were the construction of an absorption system with movement monitoring, or the relocation of the trace on the opposite bank of the river. It was decided to adopt the latter solution due to the difficulty of ensuring the stability of the terrain and the inaccessibility during the winter. It implied an additional river crossing and consequently, the need to monitor the stability of the channel to the river erosion.

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 experience gained during the operation and maintenance stages of the Camisea pipeline transportation system (STD) in Peru, crossing from the Tropical jungle in the Cusco region to the coast, in Lima city, has enabled us to develop and apply techniques in construction and maintenance works focused on controlling of the vertical undermining of riverbeds and the erosion of margins at river crossings and creeks crossed by the pipeline carrying NG and NGL. According to the above, a technical assessment study was conducted of the crosses rivers and creeks that have high priority of the Camisea pipeline path, comprising — among other disciplines — hydraulic and undermining analysis, as well as an hydrologic and geo-morphological evaluation and other issues regarding general geology and geo-techniques at each crossing site. A work program was developed using the information obtained in the three sectors travelled by the (STD) in order to develop and complement works at the crossings of rivers and valleys aiming to protect the integrity of the pipeline from erosion produced by major and extraordinary floods in riverbeds and alluvial slides in narrow valleys, by means of confinement and sedimentation works. The jobs performed in rainforest, mountain and coastal terrain crossed by the pipeline considered different river morphology types — being the most common the straight, gravel braided and curved river travels — and regimes in both flow speed and width of the riverbed. From the topographic follow-up and monitoring stage on — before and after the rain season — at crossings beneath the riverbeds, it was determined that the deterioration process affecting the crossing stripe corresponds to erosion consisting in the alteration of the watercourse banks that affects the piping foundations. The works are completed considering the type of resources available at the site of the river crossing — i. e., the engineering is particular to each sector, and designing is performed upon available materials in the area. The most utilized works at river and creeks crossings on the Camisea piping system are as follows: i) protection of riverbeds and creeks slopes using gabion mesh and pads; ii) sedimentation systems on gabion mesh; iii) Energy dissipation devices at creeks crossings; iv) rip-rap –type armoring of riverbeds; v) confinement check dams ; vi) marginal protection dikes; vii) marginal protection rock fill dams; viii) protection and sedimentation breakwaters, among others.

The Andes Mountains, rich in geographical features and diversity, poses a significant threat to the integrity of oil and gas pipelines due to geohazards. Land movement and unstable soil conditions can trigger changes in the original trajectory of the pipeline resulting in undesired bending strain which can result on failure of the facility. OCENSA – Oleoducto Central S.A. from Colombia assesses the pipeline condition in geotechnical unstable places by comparison of In Line inspection results taking into account pipeline movements and bending strains changes along the zone of study. Bending strains in the pipe are compared against allowable values and emergency values which constitute the criteria to execute mitigation and/or remediation activities that must be done in order to maintain the pipe integrity. To project the pipeline behavior in time, 3D finite element models are developed, allowing the programming of future activities. This paper presents results obtained in a study case to show how pipeline is assessed and how different mitigation activities are developed. Mitigation Techniques such as stress relief procedures and EPS (Expanded Poly-Styrene) blocks incorporations are explained. These techniques are executed in order to reduce the pipe response due to soil displacements during landslide events and creeping slopes, with the final scope of assuring a safe operation.

As of the date this paper is written pipelines in South America comprises 113000 kms of transmission lines including Oil, Gas, Condensates, and refined products from which approximately 17% (19400 kms) crosses the Andes reaching elevations up to near 5000mts. Rugged terrain combined with the geology, weather conditions (especially rain intensity) and continuous pipe ruptures in the past impose serious challenges for the pipeline industry that makes the design, construction and operation substantially different from other pipelines in the world. The records have shown that the threat of Ground movement/weather-related pipeline ruptures in the Andes plays a significant role since the percentage of the risk associated with geotechnical causes is substantially higher than any other parts such as Europe or United States. Thus the rate of pipeline failures due to natural forces is significant higher than the average industry. Peru LNG is a 406km × 34in gas pipeline transporting natural gas from the jungle side of Peru to the Pacific Coast where a LNG terminal has been installed. Peru LNG’s pipeline currently holds the record of being the highest Gas Pipeline of the world with a maximum elevation of 4901 meters above sea level. Project completion was done in May 2010 and lessons learnt from similar projects were taken into account since project designs. This paper is divided in two parts. First, it compares pipeline ruptures frequencies due to natural forces in the Andes with other pipelines in different terrains based on historical cases compiled by the authors. Secondly, it explains the different phases of Pipeline Project in rugged terrain from the conceptual design until the operations stage and the role of Pipeline Geotechnical Engineers in this process based on PERU LNG’s pipeline experience. It also describes some of the main features of the PLNG pipeline project. A comprehensive flow chart provides general guidance for future pipeline projects in similar conditions.