Only limited information existed about the occurrence of boron and chromium in drinking water sources prior to this project. In addition, chromium speciation in drinking water sources was not well understood. In fact, due to analytical method deficiencies, previous field sampling experiences had resulted in total chromium concentrations less than corresponding hexavalent chromium concentrations. This project specifically addressed the following questions: What are the analytical method challenges and sensitivities for reliable low-level detection of chromium species and boron in drinking water supplies? What are the national occurrence patterns for chromium species and boron in drinking water sources? What is the fate of these compounds through drinking water facilities and distribution systems? This research provides a new baseline of national boron and chromium, total and hexavalent, occurrence in drinking water sources. It also indicates that existing treatment technologies do not effectively remove boron or hexavalent chromium. Originally published by AwwaRF for its subscribers in 2004.