D.3.1 Materials and apparatus

water. Leachate is separated from sediment by centrifugation, and the leachate

is chemically analyzed. Fresh DDI water1 is added to the centrifuge tube to

replace that removed, and the process is repeated a minimum of four complete

cycles.2

D.3.1 Materials and apparatus

450-mL stainless steel centrifuge tubes for organic contaminants

250-mL polycarbonate centrifuge tubes with leakproof caps for metals

Weighing scale with sufficient capacity to accurately weigh centrifuge

bottle, cap, and added sediment and water

Glove box of sufficient size to contain centrifuge bottles, sediment, and

scale

High purity nitrogen gas

DDI water conforming to American Society for Testing and Materials

(ASTM) Type II (ASTM D1193-99) (ASTM 1999)

Concentrated HCl

Concentrated Ultrex HNO3

Vacuum source

Mechanical mixer

Stainless steel spatula

Paper towels

Glass fiber filter, 1 micron, 47-mm diam, binder free, (Gelman Type A/E

or equivalent)

Glass fiber prefilters, 4 micron, 47-mm diam, binder free, (Whatman

Type GD/F or equivalent)

Cellulose acetate filters, 0.45 micron, 47-mm diameter, (Millipore or

equivalent)

Filtration manifolds for organics and metals

High capacity tumbler

Muffle furnace

Oxygen meter

DDI water is the appropriate challenge water when the sediments will be exposed to

freshwater infiltration in the CDF. In some cases, dredging site water may be a more

appropriate challenge water (see Section D.2.5).

The distribution coefficient for hydrophobic organics is constant and on the order of

hundreds to thousands. In this case, an SBLT test will result in a clustered desorption

isotherm. Therefore, if the only contaminants of concern are hydrophobic organics, a

single-point isotherm, based on one SBLT test cycle, is sufficient (see Section D.2.5).

D10

Appendix D Leachate Testing Procedures