AREA A/B ENGINEERING REPORT - Waste Management

Geosyntec Consultants
control accumulation of leachate in the drainage layer consistent with the regulatory requirement
of no more than 12 inches of head on the liner. Cleanout pipes that connect directly to the main
leachate collection pipes in the landfill are incorporated into the design. This allows landfill
operators to clear debris from the LCRS if necessary to maintain design flow specifications,
thereby reducing the potential for the LCRS to have sustained periods of saturation and
decreasing the potential for development of biological fouling within leachate pipes.
3.3.3 Long-Term Performance and Longevity of Leachate Collection Systems
Leachate generated by a landfill will need to be collected during its active life and post closure
care (PCC) period until such time as active management is not required to protect human health
and the environment. The geosynthetic products (GNs, GCs, and/or GTs) and pipes used in a
modern managed LCRS are designed to accommodate the maximum anticipated loads of waste
and to be structurally stable for periods well beyond the combined duration of active landfill
operations and subsequent PCC period. 11
LCRS maintenance conditions specified in landfill facility permits issued by most
states require regular pipe inspections and cleanout as a means to demonstrate
that the piping system remains functional. Documentation of proper LCRS
operation is also required to demonstrate compliance with the site operating
permit (e.g., transmission pump performance and flow, head-on-liner
measurements, storage tank flow balance, recirculation volumes, and quality control criteria for
onsite treatment and/or offsite discharge or disposal of leachate as specifically permitted to a
surface water outlet or sewer connection to a public wastewater treatment plant).
3.3.4 Leachate Management Options
Effective leachate management can vary from site to site based on factors including climate, size
of the landfill, waste treatment goals, and location. The determinants include:
• Climate (e.g., annual rainfall, moisture content of incoming waste, volume of leachate
generated);
• Site-specific conditions (e.g., site size, landfill geometry, cover system design specifications,
and proximity to natural habitats);
• Siting considerations (e.g., distance to a publicly-owned treatment works, or POTW) and
the nature of the receiving environment (e.g., proximity and size of surface water bodies,
hydrogeologic conditions, and ecological sensitivity); and,
11 There is extensive information in the technical literature on LCRS design and performance (e.g., Rowe, 1998;
Othman, et al, 2002; and Bonaparte, et al, 2002a) as well as the design and selection of sand and geotextile filter
components (e.g., Giroud, 1982 and 1996; Lafleur, et al, 1989; Luettich, et al, 1992; and Koerner, 1998). See
Appendix B for further details.
MD10186.doc 41 29 March 2009