The Environmental Protection Agency (EPA) will issue final guidance specifically addressing petroleum vapor intrusion by the end of 2012 and it is expected to expand current practices used in assessing and mitigating chemical migration by addressing new mitigation methods, petroleum hydrocarbons and institutional controls.

Christopher Roe said final EPA vapor intrusion guidance will be a “good thing.” Even within the same EPA regions, decisions about what sampling is sufficient is “still a moving target,” he said.