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The Association of State and Territorial Solid Waste Management Officials (“ASTSWMO”) released a report addressing a risk assessment screening tool titled:

Human Health Risk Assessment Screening Tool for Atypical Risk Exposure Scenarios (“Report”)

The Report was prepared by ASTSWMO’s Investigation and Remedy Selection Focus Group pursuant to a U.S. Environmental Protection Agency Cooperative Agreement. Ms. Dianna Kilburn of the Arkansas Department of Energy & Environment – Division of Environmental Quality (“DEQ”) participated in the Report’s preparation. Ms. Kilburn serves as the Manager of the Technical Branch in DEQ’s Office of Land Resources.

The stated purpose of the Report is to:

. . . help regulators review risk assessments that do not fit typical residential or commercial/industrial scenarios.

Atypical situations are stated to include:

. . . exposures from trespassing, recreating, or short-term work assignments, etc.

The Report states that the tool is intended to help:

. . . reviewers determine if the variables used are within reasonable ranges and what variables have the highest impact on the ultimate outcome of a risk assessment.

Note that Human Health Risk Assessments (“HHRA”) are utilized to determine if site contaminants are a concern to human health and the environment. They are a tool used by federal and state environmental regulators.

Various federal and state programs use risk-based corrective action or remediation standards which tailor cleanup levels according to site-specific factors. The programs often take into account factors such as to what extent the site is accessible and/or the future land use. Typically, superimposed upon these various procedures or site specific analyses is a requirement that the resulting standards be protective of human health and the environment.

As the Report states, an HHRA uses environmental data to estimate adverse health effects based on:

• Nature
• Magnitude
• Probability

Contaminated media from which adverse health effects could occur potentially include:

• Soil
• Vapor
• Groundwater
• Surface water

As a result, the HHRA can be utilized to determine potential uses of a property and/or whether and what type of cleanup could ensure safe use utilization.

A copy of the Report can be downloaded here.