Landfill Cells

1
Landfill Cells

• What are landfill cells?
• Fill plan?
• Fill sequence?

2
Omarunui Landfill

• Hastings, New Zealand
• The delivered MSW is compacted and sculptured by
  a Bomag compactor weighing 26 tonnes
• 2 m thick cells, 30 m working face helps control
  odor and wind blown litter
• Each day waste covered with a layer of
  non-organic soil

3
Planning Package

• Operation and fill sequence plans (hand-in-hand)
• Operation plan addresses the daily operation of
  the site, landfills operation manual
• Information provided in the operation plans- used
  to develop the fill sequence

4
Operation Plan

• Compactor operations dictates cell
  construction, operator determines type of cell
  constructed, where and when the cell is ready for
  finishing and covering
• Optimum density space saving, point of
  diminishing return, high capital and operation
  cost of compactor, cost/benefit

5
Landfill Cells

• optimum cell geometry maximize volume minimize
  surface area (ideally a sphere)
• slanted cube built in realty
• computer programs determine optimal cell
  dimensions

6
Landfill Cells

• Segregate garbage by type larger material at
  the bottom finer at the top, use temporary
  stockpile
• Tasks hand-in-hand, dozer pushes the MSW to the
  compactor which builds cells, and finally
  scraper places soil for covering

7
Fill Plan

• Two-step approach long term and short term
  goals
• Long term goals identified first, where the
  site is headed in the long term
• Short term detailed annual access plan,
  placement tipping pads and stock piles

8
Fill Plan

• Fill methods depend on the specific site
  characteristics
• Site characteristics available cover material,
  topography, local hydrology, geology, etc.
• Detailed plan layout of individual cells,
  needed for gas and leachate control

9
Fill Sequence

• Planning both long term and short term depends
  on 5 main areas of operation
• Plan major fill and excavation phases, further
  subdivided, 1-2 yrs of liner at a time
• Major cost vehicle access, drainage, soil
  transportation, closure should be established

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Main Areas of Sequence Plan

• Economics larger the project lower the unit
  price of construction, time value of money
  (delaying more costly phases)
• Access roads ( high construction and
  maintenance cost), build sparingly and place
  where they will be useful for as long as possible

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Main Areas of Sequence Plan

• Drainage plan backwards (from final stage to
  present), ensure that there is proper and
  efficient drainage in every area to avoid eroding
  and weakening cells
• Excavation minimize initial excavation, avoid
  double-handling of soil, move it fast
• Filling enough capacity until next phase,
  determine minimum size of each phase then the
  most economical size, closure sequence

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Landfill CellsBasic Building Blocks of Landfills