Site Assessment is an integral part of DEQ's Environmental Cleanup Section. As the entry point into DEQ's Voluntary Cleanup and Site Response Programs, SA performs a critical "gate-keeping" function. SA staff examine sites where releases of hazardous substances have occurred or may have occurred, to determine if these sites have the potential to impact human health or the environment.
The SA Program evaluates many property types, from small commercial lots to roadside chemical spills to large industrial facilities. The program assesses all hazardous substances that can contaminate soil, surface water, sediments, groundwater, or air.
The Main Site Assessment Components Are:
- Recommending Further Action
- Listing Decisions
Each is discussed below.
Discovery refers to how SA staff learn of contaminated or potentially contaminated properties. There are many ways this can occur, such as: 1) referral from other DEQ programs or from other public agencies; 2) reports of chemical spills; 3) citizen complaints; 4) contamination appearing on adjacent properties; 5) data submitted voluntarily by property owners or their representatives; or 6) SA staff research to discover sites that could affect Vulnerable Areas in Oregon. SA staff perform quick reviews of all new site information and focus first on those sites with the greatest potential to threaten human health and/or the environment. At this time, SA adds new sites to DEQ's Environmental Cleanup Site Information (ECSI) database. ECSI is an electronic tracking system for contaminated or potentially contaminated sites, which is updated as sites progress through different stages of the cleanup process.
Site Assessment's first documented action at a site is called a screening. A screening is a brief review of readily available information on site history, contamination, and ways that human or environmental receptors could be exposed to site contamination. Screenings are primarily "desktop" exercises that occasionally include site visits, but rarely involve DEQ sampling. Screenings culminate in general recommendations for further site action that include priority rankings (low, medium, or high). Priorities are assigned based on the threats posed by contamination and the urgency in implementing further actions. SA staff use a ranking tool developed within DEQ, the Site Assessment Prioritization System Guidance and worksheet to guide their assignment of site priorities. Screenings are usually documented in written Strategy Recommendations.
At certain sites, DEQ staff will conduct a Preliminary Assessment. This involves a detailed evaluation of facility operational history, waste management practices, past sampling data (if available), and potential exposure pathways. PAs incorporate site visits and sometimes include limited sampling. However, sampling at this stage more commonly occurs during an Expanded Preliminary Assessment, which is designed to confirm the presence of contamination when a previously completed PA lacks such information.
Closely related to the PA is a Site-Specific Assessment, designed for brownfield sites. This includes sampling and is designed to find out: 1) if a property has contamination that could affect its proposed redevelopment; and 2) what further actions are needed, if any, to enhance prospects for redevelopment.
Information from SA evaluations is summarized in the ECSI database, which is available to the public.
Recommending Further Action
Depending on the amount of information available and the nature of site contamination, SA may recommend that the property owner conduct a PA, an XPA, a remedial investigation (RI), or an RI with a feasibility study to evaluate cleanup options. At some sites, all that is needed is further documentation or analysis indicating that hazardous substances pose no significant threats. At a few other sites, SA staff may be able to determine from existing documentation that no further action is necessary. Depending on site conditions and the assigned priority, SA may offer facility owners and operators the following options for further action: 1) participate in DEQ's Voluntary Cleanup Program; 2) conduct further actions independently (i.e., without any DEQ involvement); or 3) wait for DEQ's Site Response Section to initiate further action under the state's enforcement authority.
The SA Program tracks its costs in performing site evaluations, and notifies property owners or operators of this policy at the beginning of the screening process. DEQ seeks to recover these costs when SA recommends further investigation or cleanup at a site.
For public notification purposes, state law requires DEQ to maintain a Confirmed Released List and an Inventory of Hazardous Substance Sites. The CRL is a list of sites with documented releases of hazardous substances. The Inventory is a subset of the CRL, consisting of contaminated sites where a PA (or equivalent) has been completed and where further investigation or cleanup is needed to protect human health and the environment. In most cases, DEQ listing decisions originate from SA staff recommendations.
If a site meets the criteria for listing, DEQ notifies owners/operators of its proposal to add the site to the CRL and/or Inventory, and permits comments on the proposed listing. In its listing decision letter, DEQ responds to all substantive issues raised in comment letters. DEQ may decide not to list a site if new information demonstrating that the site does not meet the criteria for listing is submitted during the 45-day comment period.