A conceptual model is a representation, either written or illustrative, of the predicted relationships between ecological values and contaminants. Examples of a conceptual model diagram for XYZ Enterprises is shown below, but you may choose to undertake this process using a different diagrammatic approach. Examples of other conceptual models are shown in USEPA 1998 Appendix C. 

XYZ Enterprises Conceptual Site Model 7B Anywhere Drive