Department of Health Seal

TGM for the Implementation of the Hawai'i State Contingency Plan
Section 15.5
SITE ASSESSMENT PROCESS

15.5 SITE ASSESSMENT PROCESS

The goal of a site assessment is to characterize site conditions in order to identify the necessity for remediating soil or groundwater that poses unacceptable environmental hazards, either under current site conditions or under uncontrolled, future conditions. The site assessment is carried out by the collection and analyses of samples of soil, groundwater, soil gas, surface water, sediment, air and/or other media as needed. The EALs may be used to identify contamination above levels of potential concern. Information concerning site assessment strategies is included in Section 3.

When representative sampling at release sites demonstrate that contamination in areas of concern (i.e. decision units) are below the EALs, then a more comprehensive assessment or additional evaluation is not generally required. The presence of a contaminant at concentrations above the Tier 1 EAL indicates a potential environmental hazard. The nature and magnitude of tentatively identified hazards are described in the environmental hazard evaluation (EHE) portion of the site assessment report (see Section 13). For some FTC sites, the presence or absence of potential hazards may be identified and the contaminated soil or groundwater quickly remediated without further assessment. In cases where cleanup costs could be significant or the contamination cannot be easily remediated, a more advanced evaluation of specific environmental hazards may be necessary and advantageous to the FTC participant.

The site assessment and EHE are critical steps in the decision-making process to make FTC sites successful. HDOH recommends that participants consult with the HEER Office when developing site objectives, sampling strategies, and hazard evaluations. Coordination between the participant and the HEER Office may significantly improve the quality and timeliness of site assessment actions.

An overview of the critical steps and suggested questions to address in the site assessment process are discussed in Section 3.2. Additional details on site assessment procedures are provided in Sections 3.3 through 3.9.

The FTC process does not require the HEER Office to review or approve the site assessment summary report unless no cleanup action is required. However, the participant is strongly advised to consult with the HEER Office at this step to ensure that the strategy for progressing into the cleanup process is clear. Information prepared for the site assessment report will be necessary for the removal action report provided following completion of the removal action.

For FTC sites where site conditions and contaminant levels are below the unrestricted EALs, the HEER Office does not recommend cleanup actions. For this scenario, the participant must provide a site assessment summary report for review and approval. The site assessment summary report must include a brief evaluation of site environmental hazards, but need not include a more detailed EHE as is required for sites where contamination exceeds EALs. The participant must provide 30 days (preferably 60 days) advance notice that the FTC site assessment report will be submitted for review. The HEER Office will commit to a 30-day review process and issue the No Action Letter following resolution of any outstanding items identified during the site assessment report review.