35 Ill. Adm. Code 742.505
Tier 1 Soil, Soil Gas and Groundwater Remediation Objectives
Section 742
Section 742.505Â Tier 1 Soil,
Soil Gas and Groundwater Remediation Objectives
a)Â Â Â Â Â Â Â Â Soil
1)Â Â Â Â Â Â Â Â Outdoor Inhalation Exposure Route
A)Â Â Â Â Â Â Â The Tier 1 soil remediation objectives for this exposure route
based upon residential property use are listed in Appendix B, Table A.
B)Â Â Â Â Â Â Â The Tier 1 soil remediation objectives for this exposure route
based upon industrial/commercial property use are listed in Appendix B, Table
B. Soil remediation objective determinations relying on this table require use
of institutional controls in accordance with Subpart J.
C)Â Â Â Â Â Â Â For
this exposure route, it is acceptable to determine compliance by meeting either
the soil or soil gas remediation objectives.
2)Â Â Â Â Â Â Â Â Ingestion Exposure Route
A)Â Â Â Â Â Â Â The Tier 1 soil remediation objectives for this exposure route
based upon residential property use are listed in Appendix B, Table A.
B)Â Â Â Â Â Â Â The Tier 1 soil remediation objectives for this exposure route
based upon industrial/commercial property use are listed in Appendix B, Table
B. Soil remediation objective determinations relying on this table require use
of institutional controls in accordance with Subpart J.
3)Â Â Â Â Â Â Â Â Soil Component of the Groundwater Ingestion Route
A)Â Â Â Â Â Â Â The Tier 1 soil remediation objectives for this exposure route
based upon residential property use are listed in Appendix B, Table A.
B)Â Â Â Â Â Â Â The Tier 1 soil remediation objectives for this exposure route
based upon industrial/commercial property use are listed in Appendix B, Table
B.
C)Â Â Â Â Â Â Â The pH-dependent Tier 1 soil remediation objectives for
identified ionizable organics or inorganics for the soil component of the
groundwater ingestion exposure route (based on the total amount of contaminants
present in the soil sample results and groundwater classification) are provided
in Appendix B, Tables C and D.
D)Â Â Â Â Â Â Â Values used to calculate the Tier 1 soil remediation objectives
for this exposure route are listed in Appendix B, Table F.
4)Â Â Â Â Â Â Â Â Evaluation of the dermal contact with soil exposure route is
not required under Tier 1.
b)Â Â Â Â Â Â Â Â Soil Gas
1)Â Â Â Â Â Â Â Â Outdoor
Inhalation Exposure Route
A)Â Â Â Â Â Â Â The
Tier 1 soil gas remediation objectives for this exposure route based upon
residential property use are listed in Appendix B, Table G.
B)Â Â Â Â Â Â Â The
Tier 1 soil gas remediation objectives for this exposure route based upon
industrial/commercial property use, including the construction worker
population, are listed in Appendix B, Table G. Soil gas remediation objective determinations
relying on an industrial/commercial scenario require use of institutional
controls in accordance with Subpart J.
C)Â Â Â Â Â Â Â For
this exposure route, it is acceptable to determine compliance by meeting either
the soil or soil gas remediation objectives.
2)Â Â Â Â Â Â Â Â Indoor
Inhalation Exposure Route
A)Â Â Â Â Â Â Â The
Tier 1 soil gas remediation objectives for this exposure route are listed in
Appendix B, Tables H and I.
B)Â Â Â Â Â Â Â The
Tier 1 soil gas remediation objectives for this exposure route are based on a
default water-filled soil porosity value of 0.15 cm
3
/cm
3
and
the assumed presence of a building with a 10-cm thick, full concrete
slab-on-grade.
C)Â Â Â Â Â Â Â Appendix
B, Table H shall be used when any soil or groundwater contamination is located
5 feet or less, vertically or horizontally, from the existing or potential
building or man-made pathway. In this scenario, the mode of contaminant
transport is both diffusion and advection, which sets the Q
soil
value at 83.33 cm
3
/sec. Appendix B, Table H applies only when the
existing or potential building has a full concrete slab-on-grade or a full
concrete basement floor and walls. Pursuant to Section 742.1000(a)(9), soil
gas remediation objective determinations relying on Appendix B, Table H require
the use of institutional controls in accordance with Subpart J.
D)Â Â Â Â Â Â Â Appendix
B, Table I may be used only when all soil and groundwater contamination is
located more than 5 feet, vertically and horizontally, from the existing or
potential building or man-made pathway. In this scenario, the mode of
contaminant transport is diffusion only, which sets the Q
soil
value
at 0.0 cm
3
/sec. Appendix B, Table I applies only when the existing
or potential building has a full concrete slab-on-grade or a full concrete
basement floor and walls. Pursuant to Section 742.1000(a)(7) and (a)(9), soil
gas remediation objective determinations relying on Appendix B, Table I require
the use of institutional controls in accordance with Subpart J. As an
alternative to using Appendix B, Table I, it is permissible to use Appendix B,
Table H.
E)Â Â Â Â Â Â Â To
determine whether the Q
soil
value can be set at 0.0 cm
3
/sec,
the site evaluator shall demonstrate that all soil and groundwater located 5
feet or less, vertically or horizontally, from the existing or potential
building or man-made pathway meets the Tier 1 remediation objectives for
residential property listed in Appendix B, Table A, and the Tier 1 remediation
objectives for Class I groundwater listed in Appendix B, Table E, respectively.
c)Â Â Â Â Â Â Â Â Groundwater
1)Â Â Â Â Â Â Â Â The Tier 1 groundwater remediation objectives for the
groundwater component of the groundwater ingestion route are listed in Appendix
B, Table E.
2)Â Â Â Â Â Â Â Â The Tier 1 groundwater remediation objectives for this
exposure route are given for Class I and Class II groundwaters, respectively.
3)Â Â Â Â Â Â Â Â The evaluation of 35 Ill. Adm. Code 620.615 regarding mixtures
of similar-acting chemicals shall be considered satisfied for Class I
groundwater at the point of human exposure if:
A)Â Â Â Â Â Â Â No more than one similar-acting noncarcinogenic chemical as
listed in Appendix A, Table E is detected in the groundwater at the site; and
B)Â Â Â Â Â Â Â No carcinogenic contaminant of concern as listed in Appendix A,
Table I is detected in any groundwater sample associated with the site, using
analytical procedures capable of achieving either the 1 in 1,000,000 cancer
risk concentration or the ADL, whichever is greater.
4)Â Â Â Â Â Â Â Â If the conditions of subsection (c)(3) of this Section are not
met, the Class I groundwater remediation objectives set forth in Appendix B,
Table E shall be corrected for the cumulative effect of mixtures of
similar-acting chemicals using the following methodologies:
A)Â Â Â Â Â Â Â For noncarcinogenic chemicals, the methodologies set forth at
Section 742.805(c) or Section 742.915(h) shall be used; and
B)Â Â Â Â Â Â Â For carcinogenic chemicals, the methodologies set forth at
Section 742.805(d) or Section 742.915(h) shall be used.
5)Â Â Â Â Â Â Â Â For
the groundwater component of the indoor inhalation exposure route, the Tier 1
groundwater remediation objectives are listed in Appendix B, Tables H and I.
A)Â Â Â Â Â Â Â The
Tier 1 groundwater remediation objectives for this exposure route are based on
a default water-filled soil porosity value of 0.15 cm
3
/cm
3
and the assumed presence of a building with a 10-cm thick, full concrete
slab-on-grade.
B)Â Â Â Â Â Â Â Appendix
B, Table H shall be used when any soil or groundwater contamination is located
5 feet or less, vertically or horizontally, from the existing or potential
building or man-made pathway. In this scenario, the mode of contaminant
transport is both diffusion and advection, which sets the Q
soil
value at 83.33 cm
3
/sec. Appendix B, Table H applies only when the
existing or potential building has a full concrete slab-on-grade or a full
concrete basement floor and walls. Pursuant to Section 742.1000(a)(9),
groundwater remediation objective determinations relying on Appendix B, Table H
require the use of institutional controls in accordance with Subpart J.
C)Â Â Â Â Â Â Â Appendix
B, Table I may be used only when all soil and groundwater contamination is
located more than 5 feet, vertically and horizontally, from the existing or
potential building or man-made pathway. In this scenario, the mode of
contaminant transport is diffusion only, which sets the Q
soil
value
at 0.0 cm
3
/sec. Appendix B, Table I applies only when the existing
or potential building has a full concrete slab-on-grade or a full concrete
basement floor and walls. Pursuant to Section 742.1000(a)(7) and (a)(9),
groundwater remediation objective determinations relying on Appendix B, Table I
require the use of institutional controls in accordance with Subpart J. As an
alternative to using Appendix B, Table I, it is permissible to use Appendix B,
Table H.
D)Â Â Â Â Â Â Â To
determine whether the Q
soil
value can be set at 0.0 cm
3
/sec,
the site evaluator shall demonstrate that all soil and groundwater located 5
feet or less, vertically or horizontally, from the existing or potential
building or man-made pathway meets the Tier 1 remediation objectives for
residential property listed in Appendix B, Table A, and the Tier 1 remediation
objectives for Class I groundwater listed in Appendix B, Table E, respectively.