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7 Model User Guide

7.1 Introduction

The FCA model has been designed and developed to be easy to use. This section looks at how the FCA model was developed and provides general instructions and helpful hints for using the model to estimate the IBCfor a landfill.

Specifically, section 7.2 focuses on the scope of the model and its underlying structure, including:

  • suggested uses of the model
  • underlying assumptions
  • cost sources
  • parameters relevant to landfill activities included in the model
  • parameters considered but not included in the model
  • model default values.

Section 7.3 provides additional specific assumptions used in developing the model and general instructions, tips, and examples for using the FCA model spreadsheet, including:

  • data to collect for model input
  • how to input data to the model
  • how to adjust default cost values included in the model or override them with actual cost values
  • the flexibility of the model.

Special note

Before continuing through this document, either download the FCA model to your computer to become familiar with it, or review the worksheets and other information included in Appendices A (Landfill FCA Model Overview, Structure and Algorithm Flowcharts), B (Model Input Costs - Default Values) and E (Landfill FCA Model Typical Example - District Landfill Site) of this document.

7.2 Scope of the FCA model

The formulae of the FCA model and its option buttons, macros, and other features are embedded in a Microsoft Excel Workbook. This format makes the model an easy-to-use cost analysis tool which is in a popular software platform.

The FCA Model is available on CD and also as a download from www.mfe.govt.nz (always the latest version available).

Intended users of the FCA model include both private sector and local authority waste officers/ managers. As indicated in Table 4 below, the model can be used to assess landfill full cost.

Table 4: Potential uses of the FCA model

Estimate the indicative base cost of disposal (IBC) for:

  • a Greenfields site
  • a Brownfields site

Assess costs for:

  • each aspect of a landfill from pre-development, development, operation, and closure through to and including aftercare.

Conduct cost analyses for:

  • comparing various potential landfill sites
  • comparing the landfill option with other disposal options
  • effects on the IBC of implementing waste strategies (waste minimisation, waste to landfill reduction targets).

Compile or accrue actual costs for:

  • historical and trend analyses
  • budget development and forecasting
  • goal setting
  • performance measurement.

The summary outputs allow you to analyse costs and adjust them by conducting 'what-if' analyses of specific parameters.

Before making the FCA model available to the public, its underlying assumptions, parameters, layout and usability as well as the spreadsheet's formulae and calculations were tested using actual landfill data gathered from several local authorities. The rest of this section discusses the assumptions and cost sources used in the model, parameters included and not included in the model, and the FCA model's default values.

7.2.1 Assumptions and cost sources

Several key assumptions used throughout the model are discussed below. Additional assumptions are presented throughout this Guide.

  1. The FCA model user has collected data for the model input worksheets - General Input, Brownfields Input,Waste Input, Geometric Input, and Cost Input. Furthermore, the user understands the Full Cost Accounting concepts
  2. A New Zealand landfill would be consented under the RMA and developed and operated in accordance with modern best practice
  3. The model input costs (Appendix B) provide guidance on indicative costs (range, typical and default costs or values) for items scheduled in the model Cost Input worksheet. The rates provided are for guidance only and are likely to alter depending on relevant market and economic parameters, as well as site-specific data or conditions.
  4. The FCA model excludes the items listed in Section 5.2 and Appendix C of this document.
  5. The FCA model excludes inflation.
  6. The FCA model excludes goods and services tax (GST).
  7. The FCA model may be used for planning a new landfill facility, developing a specific site, or an existing landfill (with or without further development.
  8. The FCA model output (the indicative base cost of disposal) excludes related intangible costs or other charges such as recovery of costs from previous undercharging and taxes considerations. In order to convert the IBC output to a post-tax estimate, it will be necessary to obtain specialist advice.

Use of the FCA model requires the compilation of cost data into an appropriate form to determine landfill unit costs, and hence the IBC.

The cost values used in the FCA model are primarily derived from known or published unit costs for all capital and non-capital expenditure. Where appropriate, estimates have been made in the light of expected engineering requirements and/or standards applicable to modern landfill design and operation, which have been brought into focus through recent consent processes.

Other sources of cost and conversion values that could be used in the model include:

  • current site-development costs
  • operators of landfills of a similar size
  • consultants' reports on landfill development
  • contractor and supplier estimates and quotes
  • tendered contract prices
  • construction and contracting cost handbooks and indices.

7.2.2 Parameters included

The model is based on up to 11 information parameters and eight cost parameters relevant to landfill full cost accounting, as given in Section 5 (Table 1). These parameters correspond to the item categories/headings in the model input worksheets (General Input, Brownfields Input, Waste Input, Geometric Input, and Cost Input), which provide the space for entering most data.

7.2.3 Parameters not included

A variety of cost parameters associated with landfill management could not be included in the model because:

  • either limited cost data would be available to the model user; or
  • gathering the cost data would be too burdensome or complicated; or
  • the information was outside the definition of 'full cost' adopted for this Guide.

Such parameters include those listed in Section 5.2 and Appendix C. Although these parameters are not specifically used in the model, the model has the space and flexibility for you to manually enter additional cost items if the necessary data are available. You can do this by adding the information as a line item unit cost on the Summary worksheet. It is assumed that these additional costs have been derived outside the model (see Appendix A).

7.3 Using the FCA model

This section presents background information and general guidance for using the FCA model.

7.3.1 Hardware and software requirements

To operate the FCA model you will need to have an IBM-compatible personal computer and Microsoft Excel for Windows 97.

The model is an electronic spreadsheet. You can enter information (numbers or text) intowhite data entry cells, as well as selecting from the various check boxes, options buttons, and drop-down lists.

7.3.2 Getting started

  1. The spreadsheet has been scanned for viruses, but if you are concerned then scan the spreadsheet before use. Excel's built-in macro virus protection will need to be turned off to use the model.
  2. Open the file titled FCA Model. Before the model is completely operable, a security dialogue box may automatically pop up. At this point, you should press the Enable Macros button. The spreadsheet will then open and be fully available for use.
  3. Immediately save this spreadsheet under a different name so that you always have an unchanged master copy. Each time you assess a new site or development options for the same site, save the spreadsheet under a new file name to avoid overwriting or loss of data on the last site or option you assessed using the model.
  4. The spreadsheet has page tabs at the bottom titled Version History, Instructions,General Input, BrownfieldsInput, Waste Input, Geometric Input, Cost Input, Summary, Cashflow Detail, Cashflow Summary, Cashflow Chart and IBC Chart. The Version History page is for information only and records model corrections and modifications. The page tab for Waste Input is shown only if the Custom Waste Tonnages option is selected by the user. Similarly the Brownfields Input is shown only if the Brownfields option is selected by the user.
  5. Clicking on a tab will select a worksheet in which data can be entered or reviewed. In the FCA model data may only be entered in the General Input, BrownfieldsInput, Waste Input, Geometric Input,and Cost Input worksheets. Limited data may also be entered on the Summary worksheet once the IBC has been calculated. The remaining worksheets are read-only. Blank copies of the General Input, BrownfieldsInput, Waste Input, Geometric Input and Cost Input worksheets are provided in Appendix F.

7.3.3 Using the model input worksheets - General Input, Brownfields Input, Geometric Input and Cost Input Worksheet

The model input worksheets are designed to be easy to use. All you need to do is look for the words 'Start Here' on the Instructions worksheet. Then follow the instructions and enter data as you work your way through each white data entry cell of the worksheet. When you have finished inputting data to that worksheet, clicking on the button on the bottom of that worksheet will automatically take you to the start of the next input worksheet.

The model input worksheets (General Input, Brownfields Input, Waste Input, Geometric Input and Cost Input) are where you will input all your data. Each of these sheets is divided into the parameters and the individual items that correspond to the various aspects of landfill management. In some cases the scheduled items will have drop-down menus, data-entry cells, check boxes, option buttons, tip boxes, error warnings, and colour-coded text and cells to help you as you move through them as follows.

  • Drop-down lists allow you to select from a list of default options.
  • Check boxes allow you to answer a yes/ no question by checking or unchecking the box.
  • Option buttons allow you to select between two or more different options by clicking on the adjacent circle.
  • Tip boxes coloured pale yellowdrop down from some cells to indicate typical values and valid ranges.
  • Data-entry cells are the only cells in which you can enter data and are coloured white. All the other cells are write-protected, so you don't have to worry about accidentally deleting default values or formulae. Data in greytext can be changed but is currently not in use by the model for the scenario (either Greenfields or Brownfields) being developed.
  • Errors/warnings are provided in red to help validate certain items of data. During initial data entry warnings may appear before data are fully entered in all the worksheets. Don't worry. The warnings should be rechecked and fixed once data entry is complete and before solving the model (solving is accomplished by pressing the Solve IBC for Zero NPV button at the bottom of the Cost Input worksheet).

7.3.4 Inserting data

The following sections cover data input instruction and hints.

Table 5: General input parameters data entry

View general input parameters data entry (large table)

Table 6: Brownfields input data entry

(See sections 5.1, 5.3.2 and 5.4.1).

View Brownfields input data entry (large table)

Table 7: Geometric input data entry

View geometric input data entry (large table)

Cost input data entry

It is important to note that for those variables that require dollar value estimates, the user should input the value in today's dollars, even if this variable is relevant for a future period.

There is no need for the user to account for inflation in providing these estimates. The model automatically accounts for dollar value inputs being in today's dollars, and produces output in today's dollars. That is, inflation is not incorporated in the model.

There is provision for the user to insert certain additional items by way of "Custom Inputs". Each custom input is allocated to the model in a different way. The method of allocation is explained in the Cost Input worksheet.

Special note

Where a particular item is not wanted in the situation being modelled, a zero ($0) should be entered against it.

 

Cost Input data cover the following.

Sunk costs/asset value

(See sections 5.1, 5.3.2 and 5.4.21.)

  • Enter $ lump sum.

Table 8: Planning and pre-development

View planning and pre-development (large table)

Table 9: Base costs

Data cell What to input

Engineering- detailed design and documentation and construction management

Enter %.

Contractors preliminary and general

Enter %.

Table 10: Development - site access

Data cellWhat to input

Intersection upgrade (main road or state highway)

Enter $ lump sum.

Other roading/ network contributions

Enter $ lump sum.

Landfill access road (main road to footprint)

Enter $/km.

Special structures (diversions, bridges, etc.)

Enter $ lump sum.

Table 11: Development - site amenities

View development - site amenities (large table)

Table 12: Development - cell construction (earthworks, liner, leachate)

View the development - cell construction (earthworks, liner, leachate) (large table)

Table 13: Development - stormwater management system

Data cell What to input

Major stormwater diversions (e.g. dams, canals, etc.)

Enter $ lump sum.

Open drains

Enter $/m.

Stabilised drains/ flumes

Enter $/m.

Piped drains

Enter $/m.

Stormwater treatment - pond and instrumentation

Enter $ lump sum.

Table 14: Development - gas management system

Data cellWhat to input

Horizontal collectors

Enter $/m.

Vertical extraction wells

Enter $/m.

Ring header (below grade)

Enter $/m.

Laterals to vertical wells (above grade)

Enter $/m.

Condensate traps

Enter $ each.

Flare stations - interim and final

Enter $ each.

Table 15: Development - final cover system

Data cell What to input

Topsoil - stockpile to final cover and import topsoil to final cover

Enter $/m3.

Unsuitables - stockpile to final cover and shortfall to make up with sub-topsoil

Enter $/m3.

Sub-topsoil - stockpile to final cover and borrow to final cover

Enter $/m3.

Low permeability material - stockpile to final cover, cut to final cover, and borrow to final cover

Enter $/m3.

Geosynthetic layer

Enter $/m2.

Drainage layer

Enter $/m2.

Vegetation (grassing)

Enter $/m2.

Table 16: Operations

View operations (large table)

Table 17: Closure

Data cellWhat to input

Removal of facilities

Enter $ lump sum.

Modifications to site stormwater, leachate, landfill gas and other systems

  • Final cover - enter % of construction cost.
  • Landfill gas system - enter % of construction cost.
  • Leachate management - enter % of construction cost.
  • On-site surface water control system - enter % of construction cost.
  • Design/engineering - enter % of construction cost.

Table 18: Aftercare

View table of aftercare (large table)

Table 19: Contingencies

Data cellWhat to input

Pre-development

Enter %.

Development

Enter %.

Operations

Enter %.

Closure

Enter %.

Aftercare

Enter %.

 

7.3.5 Using default values or user-supplied values

Cost estimates can be calculated using the FCA model's default values, user-entered actual values that override the default values, or a combination of default and actual values. Cost can be quickly estimated using the model's default values. More accurate cost estimates can be generated by collecting and entering actual data specific to a site or geographic location.

In general, the more data gathered and entered into the model, the more accurate its output will be. For these reasons you should (1) identify and gather specific information on your site and on local costs (labour, equipment, material, etc.), and (2) become familiar with the scope of your specific project.

The default values used in the FCA model are considered to be national averages and should be adjusted to reflect local conditions wherever possible.

Appendix B provides tables of all of the default values used in the model. You may enter your own values in the appropriate white data entry cells in the General Input, Brownfields Input, Waste Input, Geometric Input, and the Cost Input worksheets. This process allows you to customise the model according to your specific case.

7.3.6 Using the summary and cashflow sheets and charts

The Summary worksheet is a summary of all of the critical inputs and outputs of the model. When you have worked through the General Input, Brownfields Input, Waste Input, Geometric Input and the Cost Input sheets, go back over all the input sheets to look for any error warnings(in red). If there are no warnings, press Calculate IBC for Zero NPV button at the bottom of the Cost Input sheet. This will calculate the IBCand automatically display iton the Summary sheet. You may then:

  • add a mark-up / margin to the derived IBC; and
  • add unit costs of other items in the blank whitedata entry cells/spaces provided (for example, refuse collection costs, transfer station costs, freight costs, recycling costs, green waste / composting costs, education/ waste minimisation costs, and other costs which the model does not derive but which have been calculated or estimated outside the model). The waste management system may include costs associated with assets other than the landfill itself (for example, existing or new transfer stations). The costs of operating existing transfer stations can be included as a unit cost in the blank whitedata entry cells.

This completes the model run. In addition to the Summary sheet you can print the following reports for the modelling scenario:

  • Cashflow Detail - full tabulation of costs and income over the duration of the model. The forecast annual waste tonnage is also shown in this table.
  • Cashflow Summary - summary tabulation of annual costs under the main cost input parameter headings and income over the duration of the model. The forecast annual waste tonnage is also shown in this table.
  • Cashflow Chart - gives a graphical output showing the income, expenditure and cashflow, along with the value of the aftercare fund and the forecast annual waste tonnage. The graphical output covers the model duration plus the aftercare period. You should click on the 'Set Chart Limits' button on the Cashflow Chart sheet to reset the timeline once the IBChas been solved.
  • IBC Chart - gives a graphical output showing the IBC on an annual basis over the model duration. You should click on the 'Set Chart Limits' button on the IBC Chart sheet to reset the timeline once the IBC has been solved.

All sheets may be viewed and printed. The print set-up of any worksheet may be altered by choosing Page Set-up from the File menu.

Note: A typical example of a Greenfields district landfill facility development is included as Appendix E.

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