Section Eight
LANDFILLS-B. LEACHATES
70    EVALUATION OF A FULL-SCALE PHYSICO-CHEMICAL
TREATMENT PLANT FOR REMOVAL OF BDAT
CONSTITUENTS FROM HAZARDOUS WASTE
LANDFILL LEACHATE
Bill Y. M. Liu, Project Engineer
Alan Li, Project Manager
Michael P. Henry, Project Manager
Chemical Waste Management, Inc.
Research and Development
Geneva, Illinois 60134
Bruce Kruckel, Operational Manager
Chemical Waste Management, Inc.
Model City, New York 14107
INTRODUCTION
Leachate, generated by water percolating through landfills, can be classified into the two broad
categories: non-hazardous and hazardous leachates. Basically, hazardous leachate is generated from
hazardous waste or co-disposal landfills, whereas non-hazardous leachate is generated from hazardous waste or co-disposal landfills, whereas non-hazardous leachate is defined as leachate from non-
hazardous solid waste landfills. Because of the high concentrations of contaminants in leachate,
leachate is generally treated before it can be discharged or disposed of.1
Both types of leachate can be treated with conventional wastewater treatment technologies, such as
biological treatment for organic removal, metal precipitation for metal removal and granular activated carbon (GAC) adsorption for effluent polishing.1 The effluent from these leachate treatment
plants usually discharges into Publically Owned Treatment Works (POTWs) or to surface waters
under state or federal National Pollution Discharge Elimination System (NPDES) permits. The
treatment residues are then disposed of in a hazardous landfill for hazardous treatment residues and a
solid waste landfill for non-hazardous residues. However, the treatment practice for hazardous waste
leachate will be significantly impacted and might have to change when the EPA promulgates the
Third-Third landban regulation regarding multi-source leachate on May 8, 1990.
The EPA has set on overall schedule for the land disposal program, which requires all land disposal
restriction regulations to be in place by May 8, 1990.2 The EPA divided listed hazardous wastes into
three groups (the "Third"), to be regulated in successive stages over a period of 66 months. The multi-
source hazardous leachates, regulated by the Third Third, will have to meet the treatment standards
for wastewaters and non-wastewaters before land disposal.3 The EPA developed the standards representing the best demonstrated available technology (BDAT).
The BDAT constituents, totalling 231 compounds, include volatile organics (63 constituents) and
semi-volatile organics (107 constituents), metals (16 constituents), inorganics other than metals (3
constituents), organochlorine pesticides (20 constituents), phenoxyacetic acid herbicides (3 constituents), organophosphorus insecticides (5 constituents), polychlorinated biphenyls (7 constituents) and
dioxins and furans (7 constituents).
In the proposed rule for the Third Third landban2, leachate has to meet the wastewater standard,
consisting of 228 BDAT compounds, before land disposal in the surface impoundment. Treatment
residues, such as metal and biological sludges from the leachate treatment plant, will have to meet the
non-wastewater standard before disposal in a landfill. The standard for non-wastewater includes 205
45th Purdue Industrial Waste Conference Proceedings, © 1991 Lewis Publishers, Inc., Chelsea, Michigan 48118.
Printed in U.S.A.
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