26    STORMWATER RUNOFF CONTROL: AN OPERATIONAL
DIFFICULTY FOR ABOVEGROUND INDUSTRIAL
WASTE LANDFILL
G. Selvakumar, Geotechnical Engineer
Michael S. Quinn, Geological Engineer
AWARE Incorporated
West Milford, New Jersey 07480
INTRODUCTION
The control of stormwater runoff is an essential component for an environmentally sound operation of a solid waste landfill. Typically, through the use of cover soils, steep side slopes, erosion
controls, vegetation, and drainage systems, the amount of stormwater runoff is maximized, therefore, the amount of leachate generated and ultimately collected for treatment (via a properly designed
liner), is minimized. Minimization of leachate quantities is generally favorably and typically incorporated into the operational procedure of a solid waste landfill. The benefits of leachate minimization
are realized in cost savings associated with the reduction in the drainage layer thickness, drainage layer
permeability and leachate piping system specifications, and the reduction of leachate treatment costs.
This chapter is a case history of a landfill design that does not utilize typical leachate minimization
controls, since the volume loss associated with these controls was not acceptable. In order to optimize
the permitted landfill space and maintain compliance with State regulations, a state-of-the-art leachate containment, leachate collection, and stormwater containment system was incorporated into the
design and operation of the landfill. These controls were facilitated by the availability of an existing
on-site permitted wastewater treatment system, and by the properties of the wastewater treatment
plant sludge (WTPS) that will be disposed of in the landfill. The WTPS was shown to have only
nominal environmental effects when left uncovered (i.e., the WTPS does not create a fire hazard,
dust, litter, odor problem, or a vector problem when left exposed), therefore, a variance on the use of
daily and intermediate cover soil was granted. The volume typically occupied by cover soils was now
available for additional WTPS disposal, but the absence of cover soil required treatment of all
incident rainfall over the area of the landfill. Although the quantity of runoff associated with the
rainfall can be potentially large, the availability of an on-site treatment facility will provide a cost
effective method for treatment and disposal of the runoff.
Designing under the constraints as described above required an operations procedure that would,
when implemented, contain an evacuate runoff associated with a worst-case precipitation event.1-2 A
2-day/100 year (9.3 inches) event was used as the design storm for runoff containment. The stormwater containment system was also designed to restrict flow through the primary leachate collection
system (operational sand layer, leachate collection pipes, and geonet), thereby obviating concerns of
clogging due to a high influx of sediment associated with a worst-case storm.
SITE DESCRIPTION
The landfill is a multi-cell industrial waste facility located in Ocean County, New Jersey. The
facility will provide for disposal of a wastewater treatment plant sludge (WTPS). The WTPS is
generated by the treatment of an industrial effluent produced by a chemical plant which manufactures
dyes and epoxy resins. The landfill facility consists of seven cells (2 to 3 acres per cell); two existing
cells (cell Nos. 2 and 3), one closed cell (cell No. 1), and four proposed cells (cell Nos. 4, 5, 6 and 7); as
illustrated in Figures 1 & 2. This paper presents the case history of Cell No. 3, which upon closure will
have a total capacity of 82,000 cubic yards (air space). The capacity was derived from the below
ground storage, above ground storage between the berms, and above berms as illustrated on Figure 3.
The estimated life for this cell is five years, based on a waste disposal rate of 2,000 cubic yards per
month during the first two years of operation, and 1,000 cubic yards per month for the remaining
operational life.
43rd Purdue Industrial Waste Conference Proceedings, © 1989 Lewis Publishers, Inc., Chelsea, Michigan 48118.
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