1. a) For the indoor inhalation exposure route:

   1. 1) Appendix B, Tables H and I apply only when the existing or potential building has a full concrete slab-on-grade or a full concrete basement floor and walls; and
   2. 2) Institutional controls under Subpart J are required to use remediation objectives in Appendix B, Table H or Table I.

   3. b) When the mode of contaminant transport is both diffusion and advection as described in Section 742.505 (i.e., any soil or groundwater contamination is located 5 feet or less, vertically or horizontally, from the existing or potential building or man-made pathway), the remediation objectives for soil gas or groundwater listed in Appendix B, Table H shall be used.

      1. 1) The first column to the right of the chemical name lists the soil gas remediation objectives for residential receptors.
      2. 2) The second column lists the soil gas remediation objectives for industrial/commercial receptors.
      3. 3) The third column lists the groundwater remediation objectives for residential receptors.
      4. 4) The fourth column lists the groundwater remediation objectives for industrial/commercial receptors.

   4. c) Only when the mode of contaminant transport is diffusion only as described in Section 742.505 (i.e., all soil and groundwater contamination is located more than 5 feet, vertically and horizontally, from the existing or potential building or man-made pathway), the remediation objectives for soil gas and groundwater listed in Appendix B, Table I may be used.

      1. 1) The first column to the right of the chemical name lists the soil gas remediation objectives for residential receptors.
      2. 2) The second column lists the soil gas remediation objectives for industrial/commercial receptors.
      3. 3) The third column lists the groundwater remediation objectives for residential receptors.
      4. 4) The fourth column lists the groundwater remediation objectives for industrial/commercial receptors.
   5. d) If using Appendix B, Table H, compliance is determined by meeting either the soil gas remediation objectives or the groundwater remediation objectives.
   6. e) If using Appendix B, Table I, compliance is determined by meeting both the soil gas remediation objectives and the groundwater remediation objectives.
   7. f) For volatile chemicals not listed in Appendix B, Table H or I, a person may request site-specific remediation objectives from the Agency or propose site-specific remediation objectives in accordance with Subpart I, or both.
   8. g) As an alternative to using Appendix B, Table I pursuant to subsection (c), it is permissible to use Appendix B, Table H pursuant to subsection (b).

(Source: Added at 37 Ill. Reg. 7506, effective May 15, 2013)