29    DISCHARGE OF SANITARY LANDFILL LEACHATE TO A
POTW THAT HAS NO INDUSTRIAL USERS
William M. Strachan, Engineering Manager
Rumpke Waste Removal Systems
Cincinnati, Ohio 45251
Edwin E. Thompson, Consultant
McGill Smith Punshon, Inc.
Cincinnati, Ohio 45249
Dominic E. Ruschman, President, Chief Chemist
Cardinal Laboratories, Inc.
Covington, Kentucky 41017
INTRODUCTION
The treatment and disposal of sanitary landfill (SLF) leachate is a special problem for rurally
located facilities. Such landfills many times exist in areas that are not served by publicly owned sewers
and treatment plants. Even if publicly owned facilities are available, these may not be designed to
accept high strength industrial wastewaters or may have compliance problems which would preclude
the acceptance of SLF leachate.
When seeking approval for the discharge of SLF leachate, perception problems may be encountered. Local officials involved in the administration of publicly owned treatment works (POTWs) may
not understand the technical issues involved or may be concerned with the appearance of accepting
such a wastewater from a political standpoint. Consultants to such POTWs may also be prone to
advise administrators against acceptance of SLF leachate for liability reasons. The purpose of this
paper is to document a success story that might be used by other rural landfills that are seeking to
discharge their leachate to a POTW.
GENERAL BACKGROUND
Landfills that are located where direct discharge of leachate to a publicly owned sewer is not an
option must either haul the leachate off-site for treatment and disposal or must construct an on-site
treatment plant for direct discharge. The option of constructing an on-site treatment facility can be
costly because tertiary treatment is usually required to meet established discharge standards. When
hauling leachate off-site, discharge to a commercial treatment plant can also be a costly option due to
hauling distances and disposal charges.
Of the numerous options available for leachate treatment, various biological treatment processes
have received a considerable amount of attention. Biological treatment processes that have been
studied for the direct treatment of SLF leachate include aerated lagoons, activated sludge, and
rotating biological contactors (RBCs).1 These studies have identified the treatment of high leachate
ammonia concentrations and nitrification as critical concerns in the design and operation biological
leachate treatment processes.
The direct treatment of hazardous waste landfill leachates and other high strength industrial wastewaters has been successfully achieved with the addition of powdered activated carbon to the contact
stabilization activated sludge process.2 Bench scale treatment of leachate from a National Priority List
(NPL) landfill site using this process showed excellent removal of toxic organics and ammonia
nitrogen. The use of RBCs for the direct treatment of hazardous waste landfill leachates has been
studied by the United States Environmental Protection Agency (USEPA).3 In pilot studies conducted
at the USEPA Test and Evaluation (T&E) Facility located in Cincinnati, Ohio, leachates from two
different NPL sites have been successfully treated using the RBC process. Since activated sludge and
RBC processes are commonly employed at POTWs, it follows that plants employing these processes
for secondary treatment have the potential for accepting SLF leachates for co-treatment.
49th Purdue Industrial Waste Conference Proceedings, 1994 Lewis Publishers, Chelsea, Michigan 48118. Printed in
U.S.A.
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