Order this information in Print

Order this information on CD-ROM

Download in PDF Format


Click here to make tpub.com your Home Page

Page Title: Leachate
Back | Up | Next

Click here for a printable version




Information Categories
.... Administration
Food and Cooking
Nuclear Fundamentals
  Educational CD-ROM's
Printed Manuals
Downloadable Books


Framework for Dredged Material Management
May 2004
As for effluent, partitioning analysis may be used to provide an initial estimate of
runoff concentrations, and this can be done for both oxidized and unoxidized conditions
(Price, Schroeder, and Estes in preparation). There also is now available a simplified test
procedure for prediction of runoff quality (SLRP) (Price, Skogerboe and Lee 1998 and
USACE 2003). A soil lysimeter testing protocol (Lee and Skogerboe 1983 and USACE
2003) has also been used to predict surface runoff quality with good results. The
lysimeter is equipped with a rainfall simulator and can be used in the laboratory or
transported to the field site. The soil lysimeter is a more expensive and elaborate testing
protocol, requiring large volumes of sediment and approximately 8 months for test
Computerized programs are available to compare predicted runoff concentrations
with water quality criteria (Schroeder, Gibson, and Dardeau 1995). If runoff
concentrations exceed water quality standards, appropriate controls may include
placement of a surface cover or cap on the site, maintenance of ponded water conditions
(although this may conflict with other management goals), vegetation to stabilize the
surface, treatments such as liming to raise pH, or treatment of the runoff as for effluent
(Lee and Skogerboe 1987). Risk assessment may be used to evaluate the environmental
effects associated with runoff and determine the need for controls where standards are
predicted to be exceeded, or standards are not available (Cura, Wickwire and McArlde in
preparation). Procedures for evaluation of runoff toxicity bioassay tests can also be
found in Brandon, Schroeder, and Lee (1997b).
5.3.6 Leachate
Subsurface drainage from upland CDFs may reach adjacent aquifers or may enter
surface waters. Fine-grained dredged material tends to form its own disposal-area liner as
particles settle with percolation of water, but some time may be required for sufficient
consolidation to occur. Particulate transport in leachate is also minimal. Constituents
present in leachate are primarily found in the dissolved fraction.
Evaluation of the leachate quality from a CDF must include a prediction of which
contaminants may be released in leachate and the relative degree of release or mass of
contaminants (Schroeder 2000). Pore water analysis may provide a good preliminary
estimate of leachate quality. Partitioning analysis may also be used to estimate
concentrations of constituents in leachate, based on measured sediment concentrations
(Myers, Schroeder and Estes in preparation (a)). Experimental procedures have been
developed for prediction of leachate quality from dredged material (Myers and Brannon
1991; Brannon, Myers and Tardy 1994; Myers, Brannon and Tardy 1996, USACE 2003).
These procedures are based on theoretical analysis and laboratory batch testing and
column testing, but have not been routinely applied due to the time required to perform
these tests and the associated cost.
The experimental testing procedures only give data on leachate quality. Estimates
of leachate quantity must be made by considering site-specific characteristics and
groundwater hydrology. Computerized procedures such as the USEPA Hydrologic

Privacy Statement - Press Release - Copyright Information. - Contact Us - Support Integrated Publishing

Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business