Acid mine drainage (IMAGE) Penn State Caption A new sensor could allow researchers to detect the rare earth element terbium from complex environmental samples, such as acid mine drainage—pictured here polluting a Pennsylvania stream. Credit Rachel Brennan, Penn State Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. License CC BY-NC Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.