flexibility is permitted in choice of liners, which may, for
waste and waste residue and all system components
short-term storage of wastes, be constructed of clay,
(e.g., liners), subsoil, structures and equipment which
synthetic materials or admixes. If the waste pile will not
have been contaminated by contact with the waste.
be closed for 10 years or more (and cannot be
periodically cleaned and inspected for leakage), a
as to preclude complete removal or decontamination, the
double-lined system with leak detection and monitoring
closure and post-closure requirements applying to
wells is required. Details on liner requirements are
landfills must be observed.
presented in paragraph 6-3.
containment of waste should therefore be an important
(2) A leachate collection and removal system is
consideration in initial design of a waste pile.
also required to collect any leachate that may be
Equipment needs. The type of equipment
produced in a waste pile by infiltration of moisture,
employed in operation of a waste pile depends to a large
decomposition or reaction.
Leachate systems are
extent on the waste characteristics and the size of the
discussed in paragraph 6-4. Run-on and run-off control
pile. With the exception of compactors, many of the
facilities, which are required for waste piles, are
vehicles used in landfill operations can also be employed
addressed in paragraph 6-5.
for waste piles. Bulldozers and front end loaders are
(3) If the waste pile contains particulate matter,
widely used to place wastes; scrapers can also be used
wind dispersal controls are mandated by the regulations.
on some applications, particularly where the size of the
Mechanisms for preventing dispersal of particulate are
pile and the coarseness of the waste permit the scraper
discussed under special design elements in paragraph 6-
to deposit wastes over the top of the pile. Large-scale
operations may also be able to use conveyor belts or
e. Closure. Since waste piles cannot be used
drag lines to deposit the wastes over the pile. Any
for permanent disposal of wastes, and can be permitted
equipment used to unload and place wastes must be
only for storage, closure requirements are less stringent
decontaminated before being taken out of the disposal
than for disposal facilities such as landfills. The principal
closure requirement for a waste pile which has achieved
adequate waste containment during its active life is
removal or decontamination of all