Indoor Inhalation Exposure Route

Section 742.312  Indoor Inhalation Exposure Route The indoor inhalation exposure route may be excluded from consideration if: a)         None of the contaminants of concern are listed on Appendix A, Table J and none of the contaminants of concern are volatile chemicals, as defined in Section 742.200; or b)         The requirements in subsections (b)(1)(A), (B) or (C) and (b)(2) and (b)(3) are met: 1)         Exclusion options when the contaminants of concern are volatile chemicals: A)        No building or man-made pathway exists or will be placed above contaminated soil gas or groundwater exceeding Tier 1 remediation objectives for residential property (Appendix B, Table H), provided, however, that there is also no soil or groundwater contamination exceeding Tier 1 remediation objectives for residential property (Appendix B, Table A) or Class I groundwater (Appendix B, Table E) located 5 feet or less, horizontally, from any existing or potential building or man-made pathway. B)        An approved building control technology is in place or will be placed that meets the requirements of Subpart L; or C)        If the contaminants of concern are benzene, toluene, ethylbenzene, and total xylenes only, a demonstration of active biodegradation has been made for benzene, toluene, ethylbenzene, and total xylenes such that no indoor inhalation exposure will occur.  This demonstration shall be submitted to the Agency for review and approval; 2)         The requirements of Sections 742.300 and 742.305 are met; and 3)         An institutional control, in accordance with Subpart J, will be placed on the property.