Field Application of Gravity Blind Backfilling Method to Abandoned Underground Waterlogged Coal Mine

Blind hydraulic backfilling is a commonly used technique for subsidence control of the strata over unapproachable water-logged underground excavations. In an investigation performed earlier, studies were carried out on simple gravity hydraulic blind backfilling in laboratory scale within a fully transparent model of a section of underground coal mine worked on bord and pillar method. Subsequently, field investigation at an abandoned underground waterlogged coal mine of Eastern coalfields Limited, a subsidiary of Coal India Limited, has been taken up to verify the findings obtained in the laboratory scale model study. The paper describes the field arrangements made for the backfilling process, and the use of remotely operated vehicle mounted camera and its sonar imaging facility for mapping of the abandoned underground waterlogged mine and for monitoring the progress of the sand filling during consecutive stages of the backfilling process.