Pipelines carrying acid mine drainage at Iron Mountain and Leviathan Mines (CA, USA) develop pipe scale, a precipitate that forms inside the pipelines. The U.S. Geological Survey is studying the composition of the pipe scale and the acid mine drainage water flowing through the pipeline through field samples and laboratory experimentation. This data release provides the data from the studies of the pipelines from 2012-2015 as a data compendium to a journal publication, and includes (1) water chemistry of the acid mine drainage; (2) mineralogy of pipe scale (X-ray diffraction and chemical extractions); and (3) laboratory experiment results.