In October 2014, Health Canada updated the Canadian Drinking Water Quality Guidelines including revised guidelines for ethylbenzene and xylenes. In accordance with these changes, Atlantic PIRI has amended Tier I and II screening level tables in Appendix 3 and 4  of the Atlantic RBCA User Guidance (January 2015).

Until the Atlantic RBCA Tool Kit has been upgraded, site professionals are responsible for updating the Chem/Tox database in the Tool Kit when carrying out Tier II Site Specific Target Level (SSTL) calculations for soil leaching to groundwater for potable water sites. This technical bulletin provides step-by-step guidance for updating the database.