The ITRC TPH Risk Evaluation at Petroleum-Contaminated Sites (TPHRisk-1) guidance builds on long-standing and current research, and presents the current science for evaluating TPH risk at petroleum-contaminated sites. The methods and procedures to evaluate human and ecological risk and establish cleanup requirements at petroleum release sites will assist decision makers in developing and implementing a technically defensible approach. In addition, the guidance provides information and supplemental references to assist practitioners in the assessment of fate, transport, exposure, and toxicity of TPH. Practitioners will also gain information that may be used in conjunction with classic tiered approaches for risk-based decision making (ASTM 2015b), including modifications for the assessment and remedial-decision framework for TPH impacts through direct comparison to screening levels, site-specific modification of screening levels, and complete site-specific risk assessment for sources, receptors, and pathways.