This document provides guidance on new draft standards for two chemicals – perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), and their recommended application. It will be particularly relevant to EPA-appointed environmental auditors and environmental assessors investigating potential contamination in surface water or groundwater. These draft standards have been developed as part of the recent review of the Australian and New Zealand Guidelines for Fresh and Marine Water Quality. As the standards will not be legislated in Victoria until 2018, this document provides interim guidance for the immediate application of the standards. This publication replaces 1633.1, issued May 2017, to provide a reference to the Commonwealth Government's health based guidance values released in April 2017.