Pyrbot, W., L. Shabong, and O.P. Singh.
Mine Water and the Environment 38(3):551-555(2019)

Coal mining in Jaintia Hills, Meghalaya has adversely affected the water resources of the area, leading to streams with a pH of 3-5. The prevailing situation demanded immediate neutralization and eco-restoration. The Moolawar stream in Mukhaialong village, East Jaintia Hills District, Meghalaya, India was neutralized by constructing an open limestone channel (OLC) using locally available limestone. The OLC raised the pH of the stream water from 4.31 to 6.57. The near-neutral pH has promoted the reappearance of many aquatic flora and fauna, including two species of fishes and some insects. The OLC was cost-effective and technically feasible in the rural area and prompted the construction of similar projects for improvement of water quality and ecorestoration of degraded streams. Details of the study and associated improvements in water quality and aquatic ecology are reported. To read more on the pilot project, see https://www.hindustantimes.com/india-news/limestone-can-help-to-save-meghalaya-water-bodies-polluted-by-coal-mining/story-z1j3TRxP0BjvqVyGnZY7zH.html