Figure 2. BU grain size specification example

ERDC TN-DOER-C13

July 2000

depend on the intended application. From the physical standpoint, the material specifications may

be an average grain size (D50) or a target GSD. The specifications may also include an acceptable

percentage of material finer or coarser than the desired range. For example, Figure 2 illustrates the

desired grain size range for a BU application for beach nourishment (note that specifications will

be site specific).

Figure 2. BU grain size specification example

Acceptable levels of COC are usually a function of environmental regulations or guidelines

pertaining to the type of activity associated with the BU application. Normally, these criteria or

standards will include specific concentrations of contaminants allowable, on a dry weight basis, in

a material intended for a specific BU. Regulatory agencies in some states have proposed or adopted

policies encouraging reuse of materials and provide for a case-by-case review and determination of

requirements (Olin 1998).

As previously discussed under "Material Characterization," the material specifications for antici-

pated BU should first be compared to the bulk material properties (as they exist prior to any

separation) to determine if the material can be used beneficially as is. Because chemical analysis

is extremely expensive, physical parameters, which can be quickly and inexpensively determined,

should be evaluated first. Grain size distribution may rule out certain BU without any further

analysis, or help to target a limited number of samples for chemical analysis if the GSD is compatible