s described by Qin and Huang (2004), a waste is acceptable for
direct land disposal if during TCLP testing the waste releases the
EPA hazardous constituent at levels below those criteria provided
in Table 2 for untreated waste. If the release level of the hazardous
constituent (TCLP extract concentration) is greater than these permissible limits for untreated waste (Toxicity Characteristic Criteria), the waste is deemed to have a toxicity characteristic and
must be treated for land disposal. To be eligible for land disposal,
during TCLP testing the treated waste cannot release levels exceeding the Universal Non-Waste Water Treatment Standard (UTS).
As shown in Table 3, of the EPA-hazardous and Washington
State-dangerous waste constituents analyzed in the TCLP extracts
from the ungrouted-silver mordenites or untreated wastes, silver
was the only toxicity characteristic found in any TCLP extract
above Resource Conservation and Recovery Act (RCRA)-permissible
levels for untreated waste. Barium was in each extract except for
the extract from Ag0ZI at concentrations up to 0.0007 kg Ba/m3
TCLP extract thus always below the 0.100 kg Ba/m3 UTS toxicity
characteristic designation criteria.
Fig. 11 summarizes the TCLP-test results for Ag by providing the
mean Ag concentration in the TCLP extract from each of the tested
representative or bounding untreated wastes and disposal forms.
Fig. 11 also provides the analytical method’s minimum detection
limit and the reporting limit for each set of materials and regulatory requirements: