The Excel spreadsheet presented below includes objectives for chemicals not contained in the TACO Tier I tables. These objectives are for convenience only and are not TACO Tier I objectives. Section 742.510 c) of the TACO regulations allow a person to request site-specific remediation objectives from the Agency for chemicals not included in the TACO Tables. Approval to use these objectives must still be obtained from Illinois EPA on a site specific and program basis.
The development of these objectives is based upon the USEPA's toxicity value hierarchy as specified in OSWER Directive 9285.7-53. USEPA's integrated Risk Information System (IRIS) is the first tier of this hierarchy.
Calculation of the soil remediation objectives was accomplished through use of the risk-based soil screening level (SSL) equations from Section 742.Appendix C, Table A of TACO. Default exposure durations and contact rates from Section 742.Appendix C, Table B of TACO were used in these calculations. Groundwater objectives were established following methodologies presented in the Groundwater Quality Standards, 35 IAC 620. Subpart F.