When a release of used oil has occurred, the indicator contaminants shall be determined by the results of a used oil soil-screening sample. The sample shall be analyzed for all volatile, base/neutral, polynuclear aromatic (PNA), and metal parameters listed at Appendix B of 35 Illinois Administrative Code (35 Ill. Adm. Code) 732 or 734 (also listed after the last question of this fact sheet) and any other parameters the Licensed Professional Engineer or Licensed Professional Geologist suspects may be present based on underground storage tank (UST) system usage. The Illinois EPA may add degradation products or mixtures of any of the pollutants listed above. The used oil indicator contaminants shall be those parameters listed above that exceed their most stringent remediation objective at 35 Ill. Adm. Code 742 in addition to benzene, ethylbenzene, toluene, total xylenes (BETX) and the PNAs listed in Appendix B. If none of the parameters exceed their remediation objective, then the used oil indicator contaminants shall be BETX and the PNAs listed in Appendix B.
Of the samples collected during Early Action activities, the soil sample that appears to be the most contaminated as a result of the release from the used oil UST system must be used to determine indicator contaminants. If none of the samples appear to be contaminated, then a floor sample collected from below the used oil UST must be used. This sample is to be used as a screening tool and should be collected and analyzed during Early Action. It must be collected and analyzed prior to the submittal of a site classification plan or site investigation plan.
Please be advised that sampling the tank contents is not an acceptable method to establish indicator contaminants.
For used oil UST systems, metals may be excluded from further consideration by:
For this reason, it is recommended that the soil-screening sample be analyzed for both total and soluble (TCLP or SPLP) metals and pH analysis be performed on a soil sample from an uncontaminated area.
For your information, the use of area background concentrations to exclude metals from consideration as used oil indicator contaminants does not result in a land use restriction.
After the indicator contaminants have been identified from the soil-screening sample, further sampling for the indicator contaminants is required in accordance with Early Action provisions.
Alternatively—and possibly the simplest course to follow—all Early Action samples, including the soil-screening sample, may be collected at the same time. Then, with a request to the laboratory for quick turnaround time, the soil-screening sample must be analyzed for all parameters noted above (in response to the first question of this fact sheet). At this time, too, all Early Action samples should be analyzed for BETX and PNAs (since these parameters are always required for used oil UST systems). Please note that a sufficient amount of soil should be collected per sample location for later testing of other indicator contaminants, if any.
Upon completion of Early Action activities, if compliance with applicable remediation objectives is not demonstrated, further sampling will be required pursuant to regulations governing site classification, site investigation, and/or corrective action.
The most stringent Tier 1 remediation objectives listed at 35 Ill. Adm. Code 742.Appendix B must be used for the established indicator contaminants. While the Tier 1 soil remediation objectives for residential properties are generally the most stringent, other remediation objectives (for example, the construction worker inhalation remediation objectives found at 35 Ill. Adm. Code 742.Appendix B.Table B) may be more stringent for some parameters.
In order to make the comparison between Tier 1 remediation objectives and the analytical results, the laboratory method detection level must be less than or equal to the most stringent remediation objective for each parameter. The only exceptions are those parameters whose acceptable detection limits (ADL), as listed at 35 Ill. Adm. Code 742.Appendix B.Tables A and B, are higher than the remediation objectives. Namely, the parameters with higher ADLs are:
Further, the analytical results must be reported on a dry weight basis, and all sample analyses must be performed by a laboratory accredited for the analyzed parameters. Analytical results that do not meet these criteria will not be accepted as a demonstration of compliance.
For more information, please contact the project manager on call for the Leaking Underground Storage Tank Section at 217-524-3300.
This fact sheet is for general information only and is not intended to replace, interpret, or modify laws, rules or regulations.
Revised August 2007