Establishment Of Remediation Standards

If, as a result of the assessment and risk evaluation completed as described in Section 300, it is determined that corrective action is required, remediation standards must be established. The remediation standards established in these rules must be no more stringent than applicable or relevant and appropriate federal and state standards and are consistent with Section 121 of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) (42 U.S.C. Section 9621) and Section 39-107D(2), Idaho Code, taking into consideration site-specific conditions. These standards, and any activity use limitations proposed for the site, must be established as part of a CAP approved in writing by the Department. The standards may consist of the following or combinations of the following. (7-1-25) 01. Screening Levels. The petroleum contaminant concentrations in soil, groundwater, and soil vapor in the EPA RSLs Tables. (7-1-25) 02. Risk-Based Levels. Site-specific, media-specific petroleum contaminant concentrations established in accordance with the risk evaluation procedures described in Section 300. (7-1-25) 03. Generic Health Standards. An established state or federal generic numerical health standard that achieves an appropriate health-based level so that any substantial present or probable future risk to human health or the environment is eliminated or reduced to protective levels based upon present and reasonably anticipated future uses of the site. (7-1-25) 401. -- 499. (RESERVED) 500. FACTORS WHEN PRACTICAL QUANTITATION LIMITS ARE GREATER THAN SCREENING LEVELS. Practical quantitation limits may be greater than screening levels or risk-based concentrations for certain chemicals. In such cases the following factors, or others, may be used in allowing practical quantitation limits as remediation standards. (7-1-25) 01. Analytical Method. The published or expected practical quantitation limit for a specific chemical and method, and the availability of other methods that may enable lower practical quantitation limits to be achieved. (7-1-25) 02. Method Detection Limit. The magnitude of the difference between the stated practical quantitation limit and the method detection limit. (3-31-22) 03. Sampling Procedures. The availability of alternative sampling procedures that may enable lower practical quantitation limits to be achieved. (7-1-25) IDAHO ADMINISTRATIVE CODE IDAPA 58.01.24 Department of Environmental Quality Rules for Petroleum Release Corrective Action Section 600 Page 14 04. Estimated Risk Levels. The estimated risk levels when site concentrations are assumed to be at the practical quantitation limit. (3-31-22) 501. -- 599. (RESERVED)