Analysis of heavy metal contamination soil by ICP, GFAA, CVAA for "Mahoning River corridor redevelopment project"

Abstract

The Mahoning River Corridor Redevelopment Project was formed as a cooperation between Youngstown State University (YSU) and the Ohio Department of Development (ODOD), and the Regional Growth Alliance (RGA) to determine the availability of constructive reuse of the Mahoning River Corridor from the city of Newton Falls in Trumbull County to the Ohio-Pennsylvania State Line. At the request of the Youngstown State University's Youngstown Technology Center (YSU-TDC) a limited environmental study was being performed to determine the level of regulated substances on the project area. According to the EPA and RCRA Regulations, the analysis should be done using required procedures and methods, such as TCLP for soil sample acid digestion, and ICP, GFAA, CVAA, for sample analysis. The land is considered reuseful if the levels of the hazardous substances is lower than the RCRA Regulatory Levels (see Table 8 on page 49). In this study, hazardous heavy metals were determined for approximate 37 sites and about 165 samples. The techniques such as Inductively-Coupled Plasma Emission, Graphite Furnace Atomic Absorption, and Cold Vapor Atomic Absorption were used for specific element analysis based on their different properties. TCLP was performed for the soil sample leaching and acid digestion. Eight RCTA regulatory heavy metals were determined for each sample. They are Arsenic, Barium, Cadmium, Chromium, Lead, Mercury, Selenium, and Silver. A Model 3410 ICP spectrometer was used for sequencial multielement analysis for As, Ba, Cd, Cr, Pb, and Ag with the most sensitive detection limits; CVAA was employed for Hg analysis to increase the sensitivity by reducing the loss of Hg analyte that typically occurs with flame techniques; GFAA was specifically used for Se analysis to avoid the low sensitivity encountered with the ICP method. The data obtained in this study showed that the concentration of metals determined were either below the RCRA regulatory Levels or undetectable. Site studies in the project may be suitable for re-use, once further surveying is performed.