Risk Evaluation Guidance
IDEM periodically issues technical information and announcements to supplement the Remediation Closure Guide. This page lists these resources chronologically, with newer information and announcements appearing first.
- Interim PAH and Trimethylbenzene Levels [PDF]:
- In June 2017, the U.S. EPA revised certain toxicity parameters that are not currently reflected in the IDEM Screening Levels Table. This document shows the optional levels to use until they are updated in 2018.
- Attenuation Factors:
- On October 20, 2015, IDEM issued a memorandum [PDF] to announce its acceptance of the attenuation factors described in the U.S. Environmental Protection Agency’s vapor intrusion guidance from June 2015. IDEM later issued the Attenuation Factors Technical Guidance Document [PDF] on September 29, 2016.
The technical information that appears below has been superseded by newer guidance. However, some responsible parties may be eligible to use superseded guidance when addressing releases.
- Risk Integrated System of Closure (RISC) User Guide (June 2010)
- RISC Technical Guide (February 15, 2001)
- TPH Fractionation Tool (contact the Office of Land Quality to request this document.)