EVALUATION OF BATCH LEACHING PROCEDURES FOR ESTIMATING METAL MOBILITYIN GLACIATED SOILS

Batch leaching methods have been used for several decades to estimate the potential release of contaminants from soils. Four batch leaching procedures (toxicity characteristic leaching procedure, synthetic prec ipitation leaching procedure, deionized water leaching procedure, and California waste extraction test) were evaluated for their ability to realistically quantify the mobility of metals from previously contamin ated glaciated soils. The study was conducted using soils from four di fferent sites (three in Connecticut and one in Maine). The results of the batch leaching procedures were compared with a set of continuous c olumn leaching experiments performed at two different flowrates and tw o influent pH values. The results suggested that the synthetic precipi tation leaching procedure (SPLP) was more realistic than the toxicity characteristic leaching procedure (TCLP), but still a conservative lea ching estimate for evaluating the potential for metal mobility in glac iated soils. This study suggests that using SPLP as a test for estimat ing metal cleanup levels will result in lower remediation costs relati ve to TCLP or waste extraction test (WET), but still maintain a high l evel of confidence in the protection of ground water quality.