Page 36 - DPR Rishikesh Legacy_Neat

4.1.5 CLOSURE AND POST CLOSURE MAINTENANCE PLAN

Determination of the end-use of dumpsite is essential to decide the measures of
closure and post – closure maintenance. Some of the uses of closed dumpsites
near urban centres include park, recreational area, golf courses, vehicle parking
area and sometimes even commercial development.

A closure and post closure plan for dumpsite involves following components.

- Plan for vegetative stabilization of the final cover
- Plan for management of surface water runoff with an effective drainage system.
- Plan for periodical inspection and maintenance of landfill dumpsite cover and facilities.

4.1.6 OPERATION AFTER CLOSURE

The following facilities will be operated routinely after closure:
- Leachate management system
- Surface water management system
- Environmental monitoring system;
- Cover rehabilitation and repair system;

The operating mythology will depend on the type of system adopted at the landfill.

4.1.7 DUMPSITE CLOSURE MONITORING

The objective of an environmental monitoring system is
- To find out whether a closure is performing as designed
- To ensure that the closure is confirming to the regulatory standards.
- In the unsaturated subsurface zone (vadose zone) beneath and around the closure.
- In the ground water (saturated) zone beneath and around the closure and
- In the atmosphere/ local air above and around the closure.
The parameters to be regularly monitored are:

- Gas quantity within the landfill
- Long – term movements of the landfill cover
- Quality of pore fluid and pore gas in the vadose zone
- Quality of ground water in the saturated zone
- Air quality above the landfill, at the gas control facilities, at building on or near the landfill
and along any preferential migration paths.

The frequency of monitoring shall be capable of detecting unusual event and risk in
the initial phases. This will give time to identify, diagnose the cause and enable
early steps to be taken for containment or remediation. Usually a
monthly/bimonthly monitoring frequency is considered suitable during the
operational phase as well as for 3 to 4 years after closure. The frequency can be
decreased to 2 to 3 times a year in later years, if all system performance
satisfactorily. Monitoring frequency may have to be increased if concentrations of
gases/leachate are higher (Usually during monsoon period) than expected are
detected, if control systems are changed or if drainage system gets clogged/non-
functional.
A monitoring programme must specify:

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