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10 The Sanitary Landfill

This is Anacreon’s grave.
Here lie the shreds of his exuberant lust,
but hints of perfume linger by his gravestone still.
Antipater of Sidon (c. 130 BCE)
This is Anacreon’s Grave

10.1 INTRODUCTION
Prior to enactment of Resource Conservation and Recovery Act (RCRA) (1976), what Americans
had referred to as ‘landfills’ were typically not much more than open dumps (Figure 10.1). There
was no requirement for a daily layer of soil, for example, which is important in deterring vec-
tors and preventing other hazards or nuisance conditions. As a result, insect and rodent infesta-
tions were common at pre-RCRA facilities and there were frequent fires. These facilities were
typically constructed without protective liners; therefore, contents readily leached into subsur-
face formations, including those which store groundwater. Many were sited at locations thought
to be convenient, without regard to subsurface geology or groundwater features. There was no
requirement for impermeable substrata below the landfill unit that could have prevented migra-
tion of liquids.
As a result of the RCRA regulations, modern sanitary landfills must meet stringent require-
ments for siting, construction, operation and maintenance, and final closure. The RCRA regulations
apply to all municipal solid waste (MSW) landfills that are active (i.e., receiving waste) and do not
apply to landfills that stopped accepting MSW before October 1991. Because of the complex tech-
nology required, the federal requirement for installing groundwater monitoring systems was phased
in over a period of 5 years. To protect drinking water sources, landfills nearest to groundwater
sources must comply before those that are sited farther away. By April 9,1994, landfill owners and
operators were required to demonstrate the ability to pay the costs of closure, postclosure care, and
clean-up of any known releases (U.S. EPA, 1993a).

10.2 RELEVANT DEFINITIONS UNDER THE RCRA REGULATIONS
Municipal solid waste landfill (MSWLF): A discrete area of land or an excavation that receives
household waste, and is not a land application unit, surface impoundment, injection well, or waste
pile. A MSWLF unit may also receive other types of wastes as defined under Subtitle D of RCRA,
such as, commercial solid waste, nonhazardous sludge, small quantity generator waste, and indus-
trial solid waste. Such a landfill maybe publicly or privately owned.
Existing unit: A MSWLF unit that is receiving solid waste as of October 9, 1993. Waste place-
ment in existing units must be consistent with previous operating practices or modified practices to
ensure good management.
Lateral expansion: A horizontal expansion of the waste boundaries of an existing unit.
New unit: Any MSWLF unit that has not received waste prior to October 9, 1993.

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