Risk Based Cleanup

Experience indicates that decontamination of soil and groundwater is often not feasible because of the technical limitations imposed by natural subsurface conditions and contaminant properties and/or the high costs involved. In addition, the high cost of site remediation is often inappropriate when compared to the low magnitude of impact on groundwater resources. In short, resources are often squandered trying to return sites to pristine conditions. Fortunately, the risk based corrective action (RBCA) process focuses on the goal of protecting human health and the environment rather than the goal of achieving a contaminant-free site. Earth Systems often uses the RBCA approach to greatly reduce the cost of remediation while protecting public health and the environment. We combine good science and a real world common sense perspective to develop a safe and practical technical solution. The keys to Earth Systems’ effective use of risk based cleanup are qualified and competent professionals with adequate training and experience, and keeping open communications with regulators.

Four Georgia Coastal Plain Sites

At four contaminated sites in Georgia, Earth Systems derived alternate risk based cleanup levels based on results of a potential receptor survey and analytical, three dimensional, solute transport modeling. The sites are located in the coastal plain with hydrogeology similar to many Florida sites. The potential receptor survey identified points of withdrawal for water supply, down gradient surface water bodies, basements, and underground utilities. The fate and transport modeling characterized the human health (potable wells) and ecological risk (wetlands, tributaries, and lakes) associated with the contaminated sites. Rather than full scale remedial action, RBCA models indicated that No Further Action (NFA) was appropriate at two of the facilities. For the other two sites, the Georgia Department of Environmental Protection (EPD) approved monitoring instead of active cleanup. In all four cases, funds were prioritized in a realistic and cost-effective way to maximize protection of human health and the environment.

Jacksonville Marine Repair Facility

At a shipyard in Jacksonville, Florida, Earth Systems’ feasibility study resulted in an innovative engineering control for sand blasting grit contaminated with metals from marine paint. Rather than transporting the spent grit offsite for expensive disposal as hazardous waste, the grit was incorporated into concrete paving around the site. Risk management prevented impact to sensitive receptors and allowed survival of the business and productive use of the contaminated land.

Multiple Florida Retail Petroleum Facilities

Earth Systems is a leader in the use of the Florida Department of Environmental Protection’s innovative risk-based No Further Action with Controls (NFAC) process. The FDEP Office of General Council has approved Restrictive Covenant Documents from Earth Systems to establish an NFAC status at dozens of sites.

To establish NFAC, reasonable risk assessment based restrictions must be established to ensure that the public and the environment are protected from contamination that is left in place. Property restrictions include engineering controls (generally as simple as the maintenance of an impermeable surface over the impacted area) and administrative controls (deed restrictions that prohibit the use of the property for purposes that might pose a risk to the public).