posted on 2002-07-13, 00:00authored byMorton A. Barlaz, Alix P. Rooker, Peter Kjeldsen, Mohammed A. Gabr, Robert C. Borden
Regulations governing the disposal of solid waste in
landfills specify that they must be monitored for 30 years
after closure unless this period is extended by the governing
regulatory authority. Given the wide range of conditions
under which refuse is buried, technical criteria, rather than
a specific time period, are preferable for evaluation of
when it is acceptable to terminate postclosure monitoring.
The objectives of this paper are to identify and evaluate
parameters that can be used to define the end of the
postclosure monitoring period and to present a conceptual
framework for an investigation of whether postclosure
monitoring can be terminated at a landfill. Parameters
evaluated include leachate composition and leachate and
gas production. Estimates of leachate production from
closed landfills are used to assess the potential environmental
impacts of a hypothetical release to surface water or
groundwater. The acceptability of gaseous releases should
be evaluated against criteria for odors, the potential for
subsurface migration, and greenhouse gas and ozone
precursor emissions. The approach presented here must
be tested on a site-specific basis to identify additional data
requirements and regulatory activity that might be
required to prepare regulators for the large number of
requests to terminate postclosure monitoring expected over
the next 20 years. An approach in which the frequency
and extent of postclosure monitoring is reduced as warranted
by site-specific data and impact analysis should provide
an effective strategy to manage closed landfills.