You are here:
REMEDIAL INVESTIGATIONS (RI) OF REGION 4 SUPERFUND HAZARDOUS WASTE SITES: OCTOBER 2006 – JULY 2007
Impact/Purpose:
The Remedial Investigation (RI) process is a very thorough and intensive effort to characterize the nature and extent of contamination of Superfund hazardous waste sites in Region 4, and as such, significant resources are devoted towards the successful completion of each RI project and subsequent reports discussing the findings. The findings are used by EPA to determine further action at a site.
Description:
The Region 4 Science and Ecosystem Support Division (SESD) conducts and/or provides technical assistance to Remedial Investigation (RI) projects of Region 4 Superfund sites. These RI projects require developing and implementing RI Work Plans which include a Project Operations Plan, Field Sampling and Analysis Plan, Quality Assurance Project Plan, and a Health and Safety Plan. In general, these large complex RIs involve: collecting soil, sediment, surface water, ground water and air samples, testing aquifer properties, and conducting ecological assessments and surface geophysical assessments. SESD maintains near state-of-the-art capability using the Global Positioning System (GPS) to log station locations and conduct total site surveys (site mapping). A variety of field sampling/analytical screening techniques may be used to expedite the investigation (including direct push/Geoprobe® technology for soil sampling and temporary well installation for groundwater screening). Analytical instrumentation includes field gas chromatographs (GCs) for volatile organic compounds (VOC) analysis, immunoassay for polycyclic aromatic hydrocarbons (PAH) analysis, and X-Ray Fluorescence (XRF) for metals analysis. Real-time results allow real-time decisions for a variety of site characterization issues while in the field. Once the field investigation is complete, SESD interprets the data and prepares a Remedial Investigation Report. Data interpretation may include developing contaminant concentration isopleth maps in two and/or three dimensions. The isopleths are coupled with the GPS data and this information is entered into a GIS database for final presentation and future data analysis. SESD also has the capability of determining remedial action alternatives for completing Feasibility Studies. For this reporting period, SESD was involved in approximately five Remedial Investigation projects in Region 4.