Section 259.220  Pesticides

a)         If the pesticide concentrations in soil are equal to or greater than the remediation suitability determination levels in Appendix A of this Part, the soil is considered a high risk to cause an exceedence of a Class I or Class III groundwater quality standard or a health advisory level and is also considered to contain a hazardous constituent, subject to all applicable hazardous waste management requirements and restrictions (35 Ill. Adm. Code:  Subtitle G: Chapter I: Subchapter c), and not suitable for land application pursuant to 8 Ill. Adm. Code 258.

b)         Notwithstanding the requirements of subsection (a) of this Section, applicants may demonstrate that the contaminated soils may be safely land applied pursuant to 8 Ill. Adm. Code 258.150.

c)         If the pesticide concentrations in soil are less than the remediation suitability determination levels in Appendix A of this Part, but are equal to or greater than the default soil cleanup objectives in Appendix B, the soil is considered a moderate risk to cause an exceedence of a groundwater quality standard or a health advisory level, and a corrective action plan to remediate the past contamination may be submitted to the Department and the Board for review. The soil may be suitable for the land application treatment program pursuant to 8 Ill. Adm. Code 258.

d)         If the pesticide concentrations in soil are less than the default SCOs in Appendix B of this Part, the pesticide concentrations are considered below regulatory concern and the facility may apply for a notice of closure in accordance with Subpart E.

e)         If the pesticide concentrations are less than the remediation suitability determination levels in Appendix A, but equal to or greater than the default SCOs in Appendix B, the applicant may undertake a detailed site assessment as described in Section 259.340 to develop the information necessary to propose site-specific SCOs, using the equations in Section 259.350(a). All site-specific cleanup objectives are subject to Board approval.

f)         Pesticide concentrations in soils proposed to remain in place at the conclusion of corrective actions may not exceed the default SCOs in Appendix B, unless appropriate engineering barriers, in conjunction with necessary institutional controls, are approved as part of a corrective action plan.

g)         If soil samples at a facility contain pesticides for which default SCOs are not listed in Appendix B, the applicant shall consult with the Department to develop an appropriate SCO. 

h)         The default SCOs for pesticides for surface soils in Appendix B apply to the upper 12 inches of the soil and any soil/gravel mixture within 12 inches of land surface.  The subsurface SCOs for pesticides apply from 12 inches below land surface to 60 inches below land surface.

i)          Default surface SCOs for pesticides are calculated using the equations in Section 259.350(a) and an organic carbon content (f_oc) of 0.008.  The subsurface SCOs for pesticides are calculated using an f_oc of 0.002.  If pesticides are present in soil at depths greater than 60 inches below land surface, the applicant shall measure the f_oc of at least 2 soil samples representative of the interval between 60 inches and the maximum depth at which pesticides are present in each boring within the area of contaminated soil.  The variable f_oc may not be measured in soil samples with visible evidence of pesticide contamination. The measured f_oc shall be used in the equation in Section 259.350(a) to calculate the soil cleanup objective for contaminated soil below a depth of 60 inches.

(Source:  Amended at 32 Ill. Reg. 1308, effective January 21, 2008)