The loss of drilling fluid, including slurry and lubrication, from the slurry or lubrication system. A special form of inadvertent return, where the fluid exceeds the strength and confining pressure of the ground and reaches the surface or waterway, is called a hydrofracture or frac-out.
1) A geotechnical instrument used to measure horizontal deflection transverse to an installed vertical pipe casing by passing a probe through a casing (via two sets of grooves in the casing). (2) An instrument used within the MTBM to measure pitch and roll.
A material which is not very reactive, such as a noble metal or plastic.
(1) Penetration of freshwater or groundwater into the sewer system through cracks, defective joints in the pipeline, and holes, or through lateral connections, manholes or inspection chambers. (2) All extraneous waters (storm water and ground water) which enter the wastewater collection system through various sources including, among others, pipe defects, defective service connections, manhole covers, roof leaders, and foundation drains.
The total quantity of water from both infiltration and inflow without distinguishing the source.