The Conceptual Site Model

Kyle NewmanVDEQ

What Is It?A description of hypothesized

relationships between sources, the environment, and receptors

•What has happened• What is happening• What will happen

Example Conceptual Site Model

Figure of Conceptual Site Model

Vapor Intrusion Conceptual Model

IRTC, 2007

Why Create a Formal CSM?• Helps plan site investigations• Provides context for site• Helps evaluate efficacy of

investigation• Allows reviewers to evaluate

the “same” site

CSM and Project Planning• Should be created before site investigation

(“Problem Formulation”)• Identification of data gaps- Phase I and UST needs vs. VRP SCR and Risk Assessment needs• Complete CSM will help determine type,

location, and number of samples required• Account for VRP Risk Assessment assumptions

What Makes a “Good” CSM?

• Site history full documented• Locations and types of potential releases

identified• Fate and transport of environmental

contaminants examined• All Potential current and future receptors

identified• Iterative- CSM changes as data are collected

Presentation

• Useful as separate section in SCR• Provide as a narrative• Figures helpful

Questions?