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INTRODUCTION Maintaining a minimum depth of cover is recognized as a key means of mitigation against third-party interference. The United Kingdom Onshore Pipeline Operators’ Association (UKOPA) good practice guide for managing pipelines with reduced depth of cover [1] states that the best way of determining pipeline depth of cover is to take measurements as part of an over-line survey. The guide recommends measurements should be taken at 50 m intervals but this should be modified depending on topography of the land and any known local issues such as ground erosion. ROSEN Group (ROSEN) and National Grid Gas Transmission (NGGT) have trialed a new methodology to identify reduced depth of cover over an entire pipeline. Knowledge of the locations of reduced depth of cover can help NGGT reduce the likelihood of third party interference events occurring. METHODOLOGY ground elevation data Ground elevation data can be collected using several methods. Accurate data for small areas can be collected using differential global positioning system (DGPS) survey equipment. To capture ground elevation data on a larger scale, a LiDAR sensor can be attached to aircraft. LiDAR is a remote sensing method which uses laser light to measure distance to a target and is commonly used to map terrain and surface objects. The advantage of this method is that a large amount of highly accurate data can be collected allowing large areas to be surveyed efficiently. internal insPeCtion Standards for operating high pressure pipelines require that the condition of a pipeline is established periodically. The condition is established by the use of internal