Site Investigation Process Flowchart

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The purpose of the flowchart is two-fold:

• To illustrate the progression of site investigation and the various combinations of stages that may be encountered as the extent of soil and groundwater contamination is defined.
• To provide information on how the Illinois EPA responds to site investigation budgets.

Stage 1 consists of the collection and analysis of soil and groundwater (if groundwater is encountered) samples to determine the extent of on-site contamination¹ after early action.

If the extent of on-site soil and/or groundwater contamination¹ is not defined during the Stage 1 investigation, a Stage 2 investigation is required - unless Stage 2 can be skipped or combined with Stage 3, as noted below. Stage 2 consists of the collection and analysis of soil and/or groundwater samples to determine the extent of contamination¹ at the site.

If the results of the previous stage of investigation indicate that contamination¹ extends beyond the site's property boundaries, a Stage 3 investigation is required. Stage 3 consists of the collection and analysis of soil and/or groundwater samples to determine the extent of off-site contamination¹ as a result of the release.

Once the extent of soil and groundwater contamination¹ has been defined, which may occur upon completion of Stage 1, 2, or 3, a site investigation completion report must be submitted to the Illinois EPA.

¹Contaminant levels exceed the most stringent Tier 1 remediation objectives of 35 Illinois Administrative Code 742 for the applicable indicator contaminants.

Site investigation is required if the results of early action soil and/or groundwater analyses indicate the presence of contamination¹, if free product is discovered, and/or if there is evidence that contaminated soil may be or may have been in contact with groundwater.

The approval of site investigation costs lags one stage behind the current stage because actual costs are approved after the fieldwork is performed. For example, the approval of a Stage 2 site investigation budget contains the approved actual costs for Stage 1 site investigation.

Stage 1 site investigation is performed, as prescribed at 35 Illinois Administrative Code (35 Ill. Adm. Code) 734.315, without prior Illinois EPA approval. The results of Stage 1 and the actual costs incurred are submitted with the subsequent site investigation plan or SICR.

To satisfy the requirements for a plan and budget, the tank owner or operator and a Licensed Professional Engineer or Licensed Professional Geologist must certify that the Stage 1 site investigation will be conducted in accordance with 35 Ill. Adm. Code 734.315 and that the costs of the Stage 1 site investigation will not exceed the amounts set forth in 35 Ill. Adm. Code 734.Subpart H, Appendix D, and Appendix E. Signing the 45-Day Report form satisfies the requirements for submittal of a Stage 1 plan and budget at 35 Ill. Adm. Code 734.315 and 734.310 (see Section G of the form). However, if the 45-Day Report was submitted prior to March 1, 2006, a stand-alone certification must be submitted with the subsequent site investigation plan or SICR.

The results of the Stage 1 investigation are submitted with the next site investigation plan or SICR, and the actual costs incurred during the Stage 1 investigation are submitted on the budget forms with the next site investigation plan or SICR.

Included with the Stage 2 site investigation plan, Stage 1 actual costs and the Stage 2 proposed budget are submitted separately on the budget forms. Presenting Stage 1 actual costs and the Stage 2 proposed budget separately facilitates the generation of approved line item costs² for Stage 1.

The Illinois EPA approves, or approves with modifications, Stage 1 actual costs and the Stage 2 proposed budget. For Stage 2, rather than providing proposed line item costs in the approval letter, the Illinois EPA provides specified language³ about the approval of the Stage 2 site investigation plan and budget. Modifications to the Stage 2 budget are also provided, if applicable. Approved line item costs for Stage 2 are provided in the next site investigation plan or report approval letter; refer to “Stage 2 → Stage 3.”

²Line Items: Drilling and Monitoring Well Costs; Analytical Costs; Remediation and Disposal Costs; UST Removal and Abandonment Costs; Paving, Demolition, and Well Abandonment Costs; Consulting Personnel Costs; Consultant's Materials Costs.

³Specified Language: Costs must be incurred in accordance with the approved plan and must be determined in accordance with 35 Ill. Adm. Code 734.Subpart H, Appendix D, and Appendix E.

Handling charges will be determined at the time a billing package is reviewed by the Illinois EPA. The amount of allowable handling charges will be determined in accordance with Section 57.8(f) of the Environmental Protection Act and 35 Illinois Administrative Code 734.635.

Included with the Stage 3 site investigation plan, Stage 2 actual costs and the Stage 3 proposed budget are submitted separately on the budget forms. Presenting Stage 2 actual costs and the Stage 3 proposed budget separately facilitates the generation of approved line item costs² for Stage 2.

The Illinois EPA approves, or approves with modifications, Stage 2 actual costs and the Stage 3 proposed budget. For Stage 3, rather than providing proposed line item costs in the approval letter, the Illinois EPA provides specified language³ about the approval of the Stage 3 site investigation plan and budget. Modifications to the Stage 3 budget are also provided, if applicable. Approved line item costs for Stage 3 are provided in the next site investigation plan or report approval letter; refer to “Stage 3 → SICR.”

Included with the SICR, Stage 3 actual costs are submitted on the budget forms. This facilitates the generation of approved line item costs for Stage 3. The Illinois EPA approves Stage 3 actual costs and the SICR.

Included with the SICR, Stage 1 actual costs are submitted on the budget forms. This facilitates the generation of approved line item costs² for Stage 1. The Illinois EPA approves Stage 1 actual costs and the SICR.

This scenario occurs when the extent of soil and/or groundwater contamination¹ is defined upon completion of Stage 1. This could be due to a number of reasons: the release from the underground storage tank did not travel very far in the subsoil because the release was small, the geology of the site is favorable for containing the leak within a short distance from the underground storage tank(s), or groundwater was not encountered or impacted.

Included with the Stages 2 and 3 site investigation plan, Stage 1 actual costs and the Stage 2 and 3 proposed budgets are submitted separately on the budget forms. Presenting Stage 1 actual costs and the Stages 2 and 3 proposed budgets separately facilitates the generation of approved line item costs² for Stage 1.

The Illinois EPA approves, or approves with modifications, Stage 1 actual costs and the Stages 2 and 3 proposed budgets. For Stages 2 and 3, rather than providing proposed line item costs in the approval letter, the Illinois EPA provides specified language³ about the approval of the Stage 2 and 3 site investigation plan and budget. Modifications to the Stages 2 and 3 budgets are also provided, if applicable. Approved line item costs for Stages 2 and 3 are provided in the next site investigation plan or report approval letter; refer to “Stages 2 and 3 → SICR.”

This scenario occurs when the collection of soil and/or groundwater samples on- (Stage 2) and off-site (Stage 3) is performed together. This might be desirable when one review and approval is desired from the Illinois EPA to save time.

Included with the SICR, Stages 2 and 3 actual costs are submitted separately on the budget forms. This facilitates the generation of approved line item costs for Stages 2 and 3. The Illinois EPA approves Stages 2 and 3 actual costs and the SICR.

Included with the Stage 3 site investigation plan, Stage 1 actual costs and the Stage 3 proposed budget are submitted separately on the budget forms. Presenting Stage 1 actual costs and the Stage 3 proposed budget separately facilitates the generation of approved line item costs² for Stage 1.

The Illinois EPA approves, or approves with modifications, Stage 1 actual costs and the Stage 3 proposed budget. For Stage 3, rather than providing proposed line item costs in the approval letter, the Illinois EPA provides specified language³ about the approval of the Stage 3 site investigation plan and budget. Modifications to the Stage 3 budget are also provided, if applicable. Approved line item costs for Stage 3 are provided in the next site investigation plan or report approval letter; refer to “Stage 3 → SICR.”

This scenario occurs when Stage 2 is skipped because, upon completion of Stage 1, the contamination¹ has already traveled off-site or is not present on-site. This could be due to the size or configuration of the site, or location of the underground storage tank(s).

Included with the SICR, Stage 3 actual costs are submitted on the budget forms. This facilitates the generation of approved line item costs² for Stage 3. The Illinois EPA approves Stage 3 actual costs and the SICR.

Within 30 days after the Illinois EPA approves the SICR, the tank owner or operator must submit to the Illinois EPA for approval a corrective action plan. The plan is designed to address all media impacted by the underground storage tank release.

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