Table 7: Geometric input data entry

Volume and area units

Select from dropdown box; Brownfields Input and Geometric Input worksheets must use the same units.

Leachate generation

Select options button for typical values for region that automatically selects typical values for the location displayed or custom values which need to then be inserted by the user.

Assumed in situ topsoil depth

Enter depth in metres.

Depth of sub-topsoil to be recovered

Enter depth in metres (you may also choose whether or not sub-topsoil layer is to be recovered from fill areas).

Liner

Enter thickness of low permeability material (i.e. compacted clay) in metres for each type of liner to be used as outlined in section 5.4.9.

Also refer Appendix E - Typical Example.

Final cover layer

Enter thickness of each of the proposed components (topsoil, sub-topsoil, low permeability layers) in metres.

Main landfill access road

Enter length in kilometres.

Length of boundary fence

Enter length in metres.

Leachate pre-treatment facility installation

Enter number of years after commencing landfill operation. Zero or nothing means it will not be installed.

Leachate disposal system

Enter number of years after commencing landfill operation. Zero or nothing means that it will not be installed.

Landfill flares

Enter percentage of way through life when the flares will be installed (zero or nothing means that it will not be installed).

Net airspace

Enter estimate of airspace required for each cell from preliminary design or for a required life (duration) for each cell. Enter in Mm³ or m³ (depending on which box was checked at the start)

Cell Construction

The model allows the user to select the option of cell construction in staged equal annual amounts or cell construction completed in a single year.

Select button for option preferred.

Development Programme parameters

Enter estimate of footprint area of each cell and liner type based on a theoretical landfill configuration or from preliminary design for a specific site. Enter in Ha or m² (depending on which box was checked at the start). Similar estimates may be made for disturbed area, area of the fill zone (both inside and outside the footprint), area to be cleared (allowance should be made for areas cleared for access, ponds, perimeter track, etc.), bush area to be cleared, area of specialised sub-grade treatment, area of liner protection, and final cap area.

Estimates should be made of the required cut (existing grade to base grade), useable liner from this cut area, the required fill (existing grade to base grade), useable liner from this fill area, and unsuitables volume/ proportion in the fill area. Enter in Mm³ or m³ (depending on which box was checked at the start). The accuracy of these estimates depends whether a specific investigated site or a generic site is modelled. Earthworks quantities are automatically calculated from the data above to achieve a materials balance.

Landfill perimeter access track

Enter length in metres.

Subsoil drainage

Enter length in metres.

Leachate collection system

Enter proposed system (header pipes, collection pipes, sumps, clean-out) quantities in metres or numbers as appropriate.

Stormwater open drains, stabilised flumes, and piped drains

Enter length in metres.

Gas management system (horizontal collection pipework, vertical extraction well, header pipes, laterals to vertical wells, and condensate traps)

Enter in metres and numbers as appropriate.