Advanced Potable Reuse Treatment Train (IMAGE) University of Southern California Caption This chart shows ARG levels (normalized per liter of water sample) for (A) the advanced water treatment facility (AWTF) train ("P") samples and (B) groundwater ("G") samples. Credit Adam Smith, USC Viterbi School of Engineering Usage Restrictions Please provide credit to Adam Smith, USC Viterbi School of Engineering License Licensed content 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.