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inspection tool on those pipelines which can be monitored using such devices. The inspection device typically includes systems to detect corrosion and geometric anomalies such as dents. In addition, inspection devices often include an inertial measurement unit (IMU), these units contain gyroscopes and accelerometers and are used to calculate position of the inspection device. The IMU data can be linked to known reference locations along a pipeline route to provide an accurate pipe centerline as a series of X, Y, and Z coordinates. dePth of Cover estiMation The methodology trialed to estimate depth of cover combines ground elevation data with an accurate pipe centerline derived from internal inspection. DEPTH OF COVER REQUIREMENTS In the United Kingdom (UK) guidance on minimum depth of cover for onshore high pressure pipelines is provided in IGEM/TD/1 [2] and PD 8010 [3]. NGGT operate their high pressure pipelines in accordance with IGEM/TD/1 Edition 5. Table 1 provides a summary of the minimum depth of cover requirements of IGEM/TD/1 (all editions), PD 8010 and other relevant international standards.