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.
- 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.
The technical information that appears below has been superseded by newer guidance. However, some responsible parties may be eligible to use superseded guidance when addressing releases.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.)