71    TREATMENT OF CONTAMINATED GROUNDWATER AND
LEACHATE FROM SUPERFUND SITES AT POTWs-A
CASE STUDY
Vasiliki Keramida, President
Ontario Environmental, Inc.
Indianapolis, Indiana 46204
Robert F. Holm, Administrator
Water and Land Protection Division
Indianapolis Department of Public Works
Indianapolis, Indiana 46221
INTRODUCTION AND BACKGROUND
In the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) of
1980, commonly called Superfund, Congress set up a trust fund (Superfund) to be managed by the
U.S. EPA and help pay for the study and cleanup of hazardous waste sites that threaten public health
and the environment. Sites eligible for Superfund action are listed on the National Priorities List
(NPL) by the U.S. EPA.
In 1984 the U.S. EPA listed the Northside Sanitary Landfill (NSL) site on the NPL, as a potential
source of onsite and offsite contamination, and authorized a remedial investigation/feasibility study
(RI/FS) of the site. The NSL site is located in Boone County, Indiana, about 10 miles northwest of
Indianapolis (Figure 1). The site is near the intersection of State Road 32 and U.S. 421 and is bounded
on the east and south by Finley Creek and farmlands, on the north by uncultivated farmland, and on
the west by an unnamed ditch which separates NSL from another Superfund site, the Environmental
Conservation and Chemical Corporation (Enviro-Chem) site (Figure 2). The unnamed ditch joins
Finley Creek at the southwestern corner of the landfill and Finley Creek flows into Eagle Creek about
one-half mile downstream from the sites (Figure 2). Eagle Creek flows south from its confluence with
Finley Creek for approximately ten miles before it empties into Eagle Creek Reservoir, one of the
sources of drinking water for the City of Indianapolis (Figure 3).
The Northside landfill occupies approximately 168 acres. Approximately 70 acres of the 168-acre
site has been operated as a landfill. The site have been active since at least 1962 and hazardous waste
was co-disposed of with solid waste at the NSL facility since 1967. By 1981, NSL had accepted at least
16 million gallons of hazardous substances.1 Today, NSL continues to operate as a solid waste
landfill. The facility had recurring operational deficiencies as reported by the Indiana State Board of
Health, and preliminary investigations by the U.S. EPA prior to the site's listing on the NPL had
revealed environmental problems at the site, including groundwater contamination.1 The RI/FS work
at the NSL site was started by EPA in 1984 and the Record of Decision (ROD) was issued in 1987.
The selected remedy presented by EPA in 1987 was a combined remedy for both the NSL and the
adjacent Enviro-Chem sites. An integral component of that remedy was the collection of leachate and
groundwater and on the on-site treatment of these wastes.2 EPA had concluded that both inorganic
and organic toxic contaminants in the leachate/groundwater mixture needed to be treated in order to
meet water quality based NPDES permit limits for discharge into Finley Creek, and had proposed an
onsite treatment system consisting primarily of a metal precipitation component and a powdered
activated carbon treatment (PACT) component.2 The actual treatment system was to be developed
through bench and pilot scale testing during the predesign investigations for the final remedial action.
EPA subsequently added ammonia and chloride to the list of conventional pollutants (BOD5, TSS,
etc.) to be limited in the NPDES permit, thus complicating even further the required treatment
process sequence.
Persuasive comments received by the EPA on the ROD convinced the agency that it was preferable
to implement separate, complementary remedies for the Enviro-Chem and NSL sites, rather than
applying the combined remedy originally selected. The idea, furthermore, of treating the NSL
45th Purdue Industrial Waste Conference Proceedings, © 1991 Lewis Publishers, Inc., Chelsea, Michigan 48118.
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