# 35 Ill. Adm. Code 742.227: Section 742.227 Demonstration of Compliance with Soil Gas Remediation Objectives for the Outdoor and Indoor Inhalation Exposure Routes

> Illinois · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P742_S742_227

## Section

- **Citation:** 35 Ill. Adm. Code 742.227
- **Heading:** Section 742.227 Demonstration of Compliance with Soil Gas Remediation Objectives for the Outdoor and Indoor Inhalation Exposure Routes
- **Jurisdiction:** Illinois
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** Illinois Administrative Code / Title 35 ENVIRONMENTAL PROTECTION / CHAPTER I: POLLUTION CONTROL BOARD / Part 742 TIERED APPROACH TO CORRECTIVE ACTION OBJECTIVES / Section 742.227 Demonstration of Compliance with Soil Gas Remediation Objectives for the Outdoor and Indoor Inhalation Exposure Routes

## Text

Section 742.227  Demonstration of Compliance with Soil
Gas Remediation Objectives for the Outdoor and Indoor Inhalation Exposure
Routes
a)         For
purposes of the outdoor inhalation exposure route and the indoor inhalation
exposure route, compliance with soil gas remediation objectives developed under
any tier shall be demonstrated in accordance with this Section by comparing the
contaminant concentrations of discrete samples at each sample point to the
applicable soil gas remediation objective.
b)         This
Section applies to exterior soil gas samples for the outdoor inhalation
exposure route, near-slab soil gas samples collected outside of an existing
building for the indoor inhalation exposure route, and exterior soil gas
samples collected at the footprint of a potential building for the indoor
inhalation exposure route.  Proposals to use sub-slab soil gas data for the
indoor inhalation exposure route shall follow Section 742.935(c).
c)         Sample
points shall be determined by the program under which remediation is performed.
d)         When collecting soil gas
samples:
1)         Use
rigid-wall tubing made of nylon or Teflon
®
or other material
approved by the Agency;
2)         Use
gas-tight, inert containers to hold the sample. For light sensitive or
halogenated volatile chemicals, these containers shall be opaque or
dark-colored;
3)         Purge three volumes
before obtaining each discrete soil gas sample;
4)         Use a
helium tracer or other leak apparatus detection system approved by the Agency;
and
5)         Limit the flow rate to
200 ml/min.
e)         Soil
gas samples shall be analyzed using a National Environmental Laboratory
Accreditation Program (NELAP) certified laboratory.
f)         Soil
gas remediation objectives shall be compared to concentrations of soil gas
collected at a depth at least 3 feet below ground surface and above the
saturated zone.

## Nearby sections

- [35 Ill. Adm. Code 742.200 Section 742.200  Definitions](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P742_S742_200.md)
- [35 Ill. Adm. Code 742.205 Section 742.205  Severability](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P742_S742_205.md)
- [35 Ill. Adm. Code 742.215 Section 742.215  Determination of Soil Attenuation Capacity](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P742_S742_215.md)
- [35 Ill. Adm. Code 742.220 Section 742.220  Determination of Soil Saturation Limit](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P742_S742_220.md)
- [35 Ill. Adm. Code 742.222 Section 742.222  Determination of Soil Vapor Saturation Limit](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P742_S742_222.md)
- [35 Ill. Adm. Code 742.225 Section 742.225  Demonstration of Compliance with Soil and Groundwater Remediation Objectives](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P742_S742_225.md)
- [35 Ill. Adm. Code 742.227 Section 742.227  Demonstration of Compliance with Soil Gas Remediation Objectives for the Outdoor and Indoor Inhalation Exposure Routes](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P742_S742_227.md)
- [35 Ill. Adm. Code 742.230 Section 742.230  Agency Review and Approval](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P742_S742_230.md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P742_S742_227. Check the current official text before relying on it. Not legal advice.