Chapter 11 Heap Leach Model
This chapter will walk the user through setting up and running Heap Leach Model in Opencontour. This includes setting up a new model from an established stacking plan, preparing the necessary inputs to run the model within the module, running the model, and explanations regarding various properties and functions that are output by the model.
Quick Access
- Overview
- Setting Up for a New Heap Leach Recovery Model
- Preparing the Heap Leach Recovery Model
- Heap Leach Recovery Module
- Running the Heap Leach Recovery Model
- Recovery Model Outputs
- CutterResult Recovery Model Properties
11.1 Overview
The Heap Leach Recovery (HPL) Model is used for determining the recovery sum of each block cell within the project, so that the overall performance throughout the leach pad can be assessed.
Heap Leach Outputs Overview
Before beginning, Opencontour recommends that users take a few steps to ensure that the model will run without significant errors. These next few sections will cover some of these steps up until the point of running the model. It is important to highlight that the HPL Model is run after the historical and or forecasted stacking plan has been updated and saved.
When setting up an HPL Model, it is also important to review the Project Settings that may need to be reviewed and updated if necessary. Firstly, make sure to select an appropriate measurement unit, Metric or Imperial. Make sure to update the Density value used for the project, and that the Volumetric Swell value for the project is set to 1. The BenchHeight property in Opencontour discretizes at a specified bench height. Therefore, when selecting the bench height, the discretization height is automatically set to the same value.
NOTE: The bench height is typically a fraction of the lift height. For example, a lift height of 10m can have a bench height of 2m.
This user guide assumes that the user will have the most up-to-date Project Settings, with all the project stacking information. For more information on setting up the project and Project Properties, please review Chapter 3 Project Setup.
11.2 Setting Up for a New Heap Leach Recovery Model
11.2.1 Getting Started
Find the existing project within the Project Dashboard. Begin by dragging & dropping the _all.json file into the project window, which will include the most up-to-date stacking information. Use the Q and W keys to toggle through each elevation to view the Base and Filler layers used to create the stacking project.
Stacking Project View
11.2.2 Best Practices
Before starting work on the HPL Recovery Model, it is recommended that user takes the following steps:
-
From the Utility Menu, select the Stacking module. The Leach Stacking window will default to the Progress Tab. Before the user is able to run the model, all progress icons will need to have a green checkmark; review the Heap Leach Stacking Process and how to get to this point in the process.
Stacking Module - Progress Bar
-
Ensure that the For Model box from the Progress Window has been checked; this will break up all the shapes into full blocks, which are required for successfully running the model.
Now that the Stacking Plan is in place and all the information needed to run the model has been updated, the Heap Leach Recovery Model can be prepared with it's necessary inputs and features.
11.3 Preparing the Heap Leach Recovery Model
HPL projects require the following components to be set up in the Project Window prior to running the model:
- Solution Shapes
- Plant Feature(s)
- Leach Feature(s)
- Scripts for CutterResult
This section will instruct the user on how they can go about setting these features up within their project, and the general guidelines that can be followed when doing so.
11.3.1 If Solution Shapes Already Exist Within a Stacking Plan
Activate the Solution Layer. Then, from the Cycle dropdown, select the cycle that contains the solution shapes for the project. Click on the Project Window and move up or down the elevation using the Q znd W keys to view the drawn shapes.
Solution Layer - Cycle Dropdown
Solution Shapes
11.3.2 Adding Solution to the Model
To create new solution shapes:
From the Toolbar, select Add Layer, then Add Solution Layer
Add Solution Layer
Ensure that the Solution layer is selected, select the Add Polygon tool from the Toolbar and draw the solution shape. Make sure to double click when the shape is done; this will create the shape and provide properties such as the on date (on) and days on (lt).
To create a script to apply leach properties to every model block:
From the Utility Menu, select the Create Script module and add scripts to each property.
Now that Solution information is in the Layer Menu, it is important to update the Model Layer. Select the Update Solution button from the Recovery Model module from the Utility Menu in the Progress Tab. The user may choose to Add BreakThrough Time onto the solution polygons that exist in the Solution layer.
If the project has CutterResult blocks that have an on and lt properties written to them via a script the Update Solution together with Add BreakThrough Time function will append however many days it takes to break through onto the lt property. The breakthrough time is calculated based on the global inputs of the project and distance to liner.
It is recommended that the user reviews their data for the App Rate and Leach Time. App Rate is the ar field in the table in the Solution Tab in the Recovery Model menu. Leach Time is dealt with in the Solution Layer.
When the Solution is updated, all the CutterResult shapes that have an on and lt and all the solutions shapes are combined and written to the Model Layer. To view the shapes, activate the Solution Layer and click the A key. The Solution Shapes can now be seen within the Model.
11.3.3 Adding a Plant Feature
Heap Leach projects will usually have one plant feature in the Schedule Layer, to represent where the solution will be processed. Plant features contain the following editable properties by default:
| Property | Description |
|---|---|
| z | Elevation of feature upon creation |
| type | Designates type of schedule feature |
| name | Name of individual plant feature |
| Q_tar | Max flow rate target |
| designation | Indicates number to track where flow goes to and comes from |
| barren_tenor | % Content of metal contained within solution during a given day. Use CSV to import data for this property |
| barren_flow | Flow rate of solution during a given day. Units change dependent on project settings (m^3/hr or gal/hr). Use CSV to import data for this property |
Select the Schedule Layer from the Layer Menu, then select Add Plant Features. The icon will turn orange when it is active, then click in the Project Window. The Plant Properties window will appear. Add as many plants as needed, then deactivate the Schedule layer.
Add Plant Features
Once a Plant has been created, the user can manually update its properties and upload historical data (if applicable) from a CSV file.
If the project contains historic barren flows and tenors, the user can upload a csv file with all the necessary information. use the Properties (p) tool to query the created plant feature. The Properties window will pop up, select CSV and search for the file. If information already exists within the feature, the user can select Clear CSV to empty the existing data.
Plant Feature Properties Window
NOTE: Turn the Schedule Layer back on to ensure the number of plants is correct. If there are more than necessary, select the Delete Tool, and remove the ones that are no longer needed.
11.3.4 Adding a Leach Feature
Heap Leach projects will also require the user to add a leach feature to the Schedule Layer, which represents the leach pad upon which metal will be extracted. Leach features contain the following editable properties by default:
| Property | Description |
|---|---|
| z | Elevation of feature upon creation |
| type | Designates type of schedule feature |
| name | Name of individual plant feature |
| leaching_R | Currently under leach (top blocks between on/off dates) |
| leaching_I | Currently under leach (top blocks between on/off dates) |
| unleaching_R | Loaded, but not currently leaching (before or after on/off dates) |
| unleaching_I | Loaded, but not currently leaching (before or after on/off dates) |
| unloaded_R | Liner, designated through Phase Liner polygon in Solution Layer |
| unloaded_I | Liner, designated through Phase Liner polygon in Solution Layer |
| evap | Evaporation % to be applied to barren flow at the drip emmiters |
Select the Schedule Layer from the Layer Menu, then select Add Leach Features. The icon will turn orange when it is active, then click in the Project Window. The Leach Properties window will appear. Add as many leach features as needed, then deactivate the Schedule layer.
Add Leach Features
Once a Leach feature has been created, the user can manually update its properties and upload historical data (if applicable) from a CSV file.
If the project contains historic information such as solution inventory or stagnant/flowing metal concentration, the user can upload a csv file with all the necessary information. use the Properties (p) tool to query the created leach feature. The Properties window will pop up, select CSV and search for the file. If information already exists within the feature, the user can select Clear CSV to empty the existing data.
Leach Feature Properties Window
11.3.5 Scripting for the CutterResult Layer
The ltp property defines leach type within the HPL module, indicating that certain ore types will be associated with their own application rate (ar), application rate variance (ar_v), as well as outflows and inflows. These properties and their functions will be covered more extensively later in this chapter.
Opencontour defaults the leach type (ltp) to 1 within the module. However, it is recommended that the user reviews their leach types after adding a Plant(s) and create scripts to designate them accordingly. Under the Utility Menu, select the Create Scripts module. The module will enable the user to create a script to assign the appropriate ltp to each of their CutterResult shapes.
- Choose Layer → CutterResult
- Prop (Properties) → ltp(Leach Type)
- Script Expression → 1(Default)
If more than one ltp properties are present within the project, update the script accordingly, then select SaveScript and Run Script. The user will be prompted with information on how many scripts were calculated. Then, close the window.
11.4 Heap Leach Recovery Module
The next step of preparing the HPL Model is to review all inputs that are internal to the Leach Model module.
From the Utility Menu, select the Leach Model module; the pop-up window will default to the Progress tab. It is recommended that the user reviews and adjusts, if necessary, the number of dates that they wish to run the model for. The number of days will impact the overall runtime of the model.
The following sections will cover each tab in the Leach Model module, and give definitions for what each of the inputs functionally do.
11.4.1 Progress Tab
The Progress Tab is used to track the progress of running the leach model. Upon opening the Leach Model module for the first time, it is the first tab that the pop-up will display:
HPL Progress Tab
There are four primary steps that a user must take to run the model:
CutterResult
The HPL Module will check to see if the user has uploaded CutterResult shapes to their project. Please note that the model is only able to run if the shapes have been discretized with the For Model checkbox selected, which is a step that must be completed while creating the stacking project. For more information please refer back to Chapter 10 Heap Leach Stacking.
Update Solution
After the CutterResult shapes have been uploaded, the user must then ensure that they have drawn out all necessary solution shapes. Once they have, they can return to this window and click the Update Solution button, which will check each solution shape (or CutterResult Layer if using scripts) for an on and lt property. This will then populate the Model Grid with the dynamic solution information.
A user may also choose to select the Add Breakthrough Time button, which will add the following properties to the Solution Layer:
| Property | Description |
|---|---|
| Breakthrough Time (bt) | The time it takes for solution to reach the liner of the leach pad from the leaching start point |
| Leach Height (lchHt) | The overall height of leaching (top to liner) associated with each solution shape |
Plant
This step checks the project for an existing Plant feature within the Schedule layer. If the Plant button is clicked again after already containing a Plant feature, another plant feature will be added to the project.
Extraction Kinetics
This step will check that the user has uploaded their extraction kinetics data for the project. For more information on this topic, please see Chapter 11.4.4.
11.4.2 Global Inputs
The Global Inputs tab specifies various controls that apply to each and every block in the project, and are present throughout the entire specified duration.
HPL Global Inputs
Each control will be listed by it's respective category in the tables below.
Global
| Input | Definition |
|---|---|
| Start | Start date for the Model to run from – taken from the earliest 'pm' property, no user input required. |
| Run Duration | Length in days the model will run for. Updating the Run Duration will automatically update the End Date |
| End | End date the model will run for. Updating the End input will automatically update the Run Duration. |
NOTE: It is recommended that the user adjusts the number of days to reflect a shorter period unless the user requires all data at once.
Plant
| Input | Definition |
|---|---|
| Plant Efficiency | Allows user to input a percentage that defines the efficiency of the plant feature. |
| Barren Concentration | Allows user to input the concentration of metal contained in the barren solution. |
Operational
| Input | Definition |
|---|---|
| Flowing Solutions Fraction (%) | mass flowingsolution / mass stagnantsolution = the assumed % of solution actively flowing within the model. A calibration factor that represents the percent of solution moving between vertical blocks. 20% is the tested field standard. The majority of leach models will not need to adjust this number. Further definition and research can be provided by Opencontour if requested. |
| Mass Transfer Coefficient (0 – 1.0 ; 1 / h) | The resistance to transfer of solute between the flowing and stagnant streams. A calibration factor that represents the speed at which gold particles transfer into the flowing solution. 0.05 is the tested field standard. The majority of leach models will not need to adjust this number. Further definition and research can be provided by Opencontour if requested. |
| Dry Ore Bulk Density | mass / volume (lbs/ft3, tonne/m3) = placed ore dry density for each block. Density of each cutter result block. |
Moisture Control
| Input | Definition |
|---|---|
| Leach Capacity (lc) | mass solution / mass dry ore = the percentage moisture on a weight basis when solution no longer drains from the material. The steady state gravimetric moisture content when the ore is being leached, based on lab data and heap leaching methodology calculation for unsaturated flows. This can be provided by a metallurgist based on analysis of lab data and other ore properties. |
| Field Capacity (fc) | mass solution / mass dry ore = the percentage moisture on a weight basis when solution no longer drains from the material. The residual gravimetric moisture content, based on lab data. Typically found from compacted permeability testing. |
| Initial Moisture Content (imc) | The initial moisture content refers to the percentage of water contained in a block prior to any leaching activities. |
| Reference Application Rate (r_ar) | The reference application rate refers to the application rate through subsequent blocks after the solution has been released by the solution shape and passed through the first block level. |
Grid Parameters
| Input | Definition |
|---|---|
| Width | Width of each grid cell |
| Length | Length of each grid cell |
| Area | Area of each grid cell |
| Height | Height of grid cell block |
Extraction Delay By Depth
| Input | Definition |
|---|---|
| Cut Point (ft/m) | The depth at which extraction is assumed to proceed at 50% of the rate at the surface. Default to 100 meters. Scientific factor that simulates extraction delay by depth. 300 feet or 100 meters is the tested field standard. The majority of leach models will not need to adjust this number. Further definition and research can be provided by Opencontour if requested. |
| Slope | The relative sharpness of the change in extraction rate with depth. Default to 4. Scientific factor that simulates extraction delay by depth. 3 is the tested field standard. The majority of leach models will not need to adjust this number. Further definition and research can be provided by Opencontour if requested. |
Draindown
| Input | Definition |
|---|---|
| Closure | Date to apply closure logic. Further detail of closure logic can be provided by Opencontour |
| Discharge Flow Rate | Flowrate to treatment facility applied at the closure date. Further detail of closure logic can be provided by Opencontour |
11.4.3 Systems
The Systems tab contains any data stored as an array (i.e. time series data), whether that is climate, barren tenor, or barren flows. The input bar within this tab will display each feature (Plant, Pond, or Leach) that has been added to the Schedule Layer, as well as any data contained in each feature.
HPL Systems
The table below shows a breakdown of each column in the Systems tab, along with a description of their intended function(s):
| Name | Description |
|---|---|
| System | List of each feature (Plant, Pond, or Leach) contained in the project |
| Data | Headers imported from a time series .CSV (e.g. leaching_I, unleaching_I, unloaded_I, barren_flow, barren_tenor) for each listed system |
| Ranges | Min/Max dates of the system's data |
| Input Bar | View multiple systems' data through a cumulative X & Y line chart (generated by Plotly) |
Some projects will have climate data. If this is the case for the project, please review the following steps. Otherwise, ignore this step.
Adding Climate Data
Opencontour recommends the following column header and formatting when creating a climate properties CSV file. All inputs other than the date will need to be defined as metric or imperial:
| Measurement System | Units of Measurement |
|---|---|
| Metric | millimeters/day |
| Imperial | inches/day |
To import climate data for a project:
-
Activate the Schedule Layer, then locate the existing Leach feature within the project. Use the Properties (p) tool to view its properties.
-
From the Properties window, click the CSV button to upload a CSV or manually update information by typing out the property and its associated values (separated by commas).
11.4.4 Extraction Kinetics
The Extraction Kinetics tab contains the extraction curves, which indicates the unique extraction rate for each ore type (ow). The ow designation for each placed block will be associated with the mine plan. The user must add the extraction equations here manually, and associate them to each ore type in the project.
HPL Extraction Kinetics
The Add button can be used to add additional rows to facilitate more ore types within the project. The Delete button removes rows starting from the bottom of the list, or whatever row has been highlighted by the user.
The table below outlines each required property that must be added to complete an extraction curve:
| Name | Definition |
|---|---|
| name | Name to add to an extraction curve |
| a | A rate factor for the extraction equation, based on metallurgical test data. Opencontour can provide tools to create these equations based on test data. |
| b | A second rate factor for the extraction equation, based on metallurgical test data. Opencontour can provide tools to create these equations based on test data. |
| ultimate | The ultimate extraction value for that ore type, based on metallurgical test data. |
| designation | This property (must be a number) will match the ow property from the mine plan to correlate the extraction curves to the correct ore type |
Once all inputs are in place, click the Save button at the bottom of the window to save all the inputs. If the user chooses to later save out the project file by navigating to Save > Save Group, these inputs (including the other tabs in this module) will be included with the saved file.
NOTE: All graphs can be updated to suit the user’s needs. Opencontour allows for simpler modifications within the software or by editing data using the integrated third-party cloud software, Plotly Chart Studio.
11.4.5 Solution
The Solution tab is used to modify parameters associated with leach type (ltp) that tend to change over time on a block-by-block basis.
HPL Solution
The table below details each property that can be controlled through this tab:
| Name | Definition |
|---|---|
| ltp | Leach Type. Used to group blocks and assign specific properties (historic vs forecast, different initial moisture contents, ROM vs Crush, applied app rates, etc.) |
| ar | Application Rate (L/m2-hr or gpm) |
| ar_v | Application Rate Variance, used when the Modify Application Rate checkbox is checked and is the percentage the app rate is allowed to change in decimal format (e.g. 0.3 is a 30% variance). |
| outfl | Assign where the pad drains to throughout time, based on each block's days leaching. |
| infl | Assign where the pad receives solution throughout time, based on each block's days leaching. |
The Write properties to CutterResult based on 'ltp' button write all properties defined in the table to each block in the CutterResult layer, group by the leach type (ltp) property.
When assigning the value to ltp, remember that this number(s) is exclusive and unrelated to the Designation number given to the plant or pond. For example, 1 = ROM and 2 = Crushed.
Typical model operation will have the Modify Application Rate checked. Once plant ramp up is achieved and the target flow rate (Q_tar) is met, the application rate will vary within the bounds of the ar_v and the plant flow rate will remain constant. Q_tar and designation properties can be edited within the plant icon in the Schedule layer.
Now, the user can assign their inflows and outflows.
Inflows and Outflows
Before updating the inputs for the Solution Inflows/Outflows make sure to check the designation property, which indicates where flow is coming from or going. If a project has more than one plant or pond, and different timelines, the user will be required to add rows for each feature.
The target flow target (Q_tar) can only be updated within the properties window for each Plant or Pond. To edit this input, close this window, go back to the Project Window, and query the feature using the Properties (p) tool.
To begin adding inflows and outflows, follow the steps below:
-
Assign the following properties to the table in the Solution tab:
- ltp → Leach Type #
- ar → Application Rate (L/m2-hr or gpm)
- ar_v → Application Rate Variance (OPTIONAL)
ltp Inputs
-
Within the table, navigate to the outfl button for the first leach type. It should direct the user to a sub-table that will be used to assign where drainage from the leach pad will go to based on the leaching days established in the project.
To utilize this table, assign the start day (start) and end day (end) within the table, along with the feature designation number (designation). To add another row to the table, select the Add button.
Outflows Table
When the user has finished assigning each of their inflows for the particular leach type, they can select the Save button at the bottom of the window. Repeat this step for each leach type within the project.
-
Within the table, navigate to the infl button for the first leach type. It should direct the user to a sub-table that will be used to assign where application rate will be received from based on the leaching days established in the project. The Q_tar property can not be edited in this window.
To utilize this table, assign the start day (start) and end day (end) within the table, along with the feature designation number (designation). To add another row to the table, select the Add button.
Inflows Table
When the user has finished assigning each of their inflows for the particular leach type, they can select the Save button at the bottom of the window. Repeat this step for each leach type within the project.
NOTE: If a project has more than one ltp (i.e. 1 and 2), then the software will target the sum of both running at the same time, in the designated units for the whole pad.
-
Once the user has finished all of their inputs, select the Write properties to the CutterResult based on 'ltp' button.
11.5 Running the Heap Leach Recovery Model
Once all of the parameters and information have been input as show above, the HPL Model is nearly ready to run. However, the user has several more parameters they must configure prior to running.
Within the Outputs tab, there are several dropdowns that will configure how the model will be run:
HPL Dropdown Selections
| Dropdown Name | Description |
|---|---|
| Zone | Allows users to select what zone within their project they would like to run the model in (Default = All) |
| Units | Allows users to select what units they would like to display their results in (g or oz) |
| Metal | Allows users to select what metal will be analyzed in accordance with model run (Au, Ag, etc.) |
| Aggregation | Allows users to break up their data for viewing within each chart (Daily, Weekly, Monthly, Cumulative). This setting can be adjusted after the model has been run |
| Ore & Solution Dropdowns | Allows users to select the data series from each system that they would like to include in the model run |
As a last minute checkup, the user may choose to save and export the settings that they have input for each of the tabs within the HPL Module. To do this, check the Export box at the bottom of the window, then click Save.
Once this has been completed, the user may then click on the Run button. The model will typically take 1-10 minutes to run completely, depending on the size of the project being analyzed.
11.6 Recovery Model Outputs
The Outputs tab in the HPL Module will populate with the results of the analysis after the model has finished running. This tab splits results out into two distinct charts:
- Ore - Used to visualize values related to the selected metal, such as total amounts of metal realized, metal placed, metal remaining, etc.
- Solution - Used to visualize values related to solution inventory, such as applied flow rate, precipitation runoff, draining flow rate, etc.
HPL Outputs - Ore
HPL Outputs - Solution
After the model has been run, there are two additional controls within the Outputs tab that can be used:
- Clear - Clears out the series data from either the Ore or Solution dropdowns so that the user can re-input them for another model run
- Data - Saves the last model run to a CSV file that is downloaded to the user's computer
Aggregate Functions
This section will cover and define each of the aggregate functions that can be run and analyzed by Opencontour's HPL model. Additionally, this section will indicate the return type of each function. The table below details what each return type means in the context of each aggregation range:
| Return Type | Description |
|---|---|
| N/A | Indicates that no result are applicable and nothing should be displayed for that result and aggregation |
| Delta(t) | Delta(t) = (day + 1) – (day) |
| MEV | Month End Value (linearly interpolated, more of a curve than stepwise) what occurs now with the monthly function sum |
| Total | Total = Sum of Delta(t) over time period |
Ore
Ore Property Definitions
| Property | Definition |
|---|---|
| total_metal_placed (oz,g) | Total contained metal in the model. This value is used to check that the amount of gold loaded in the model is the same as that indicated in the placement schedule. This value can be slightly different than the input schedule due to discretization and rounding, but the reported values must match the input exactly. |
| metal_realized (oz,g) | The total accumulating mass of metal exiting the model over period of time. This is referred to as "metal realized from the pad." This is NOT gold produced in the sense of saleable gold. This mass will include metal recirculated in the barren solution. |
| net_metal_produced (oz,g) | Metal production determines how gold leaves the system and hence how the concentration of the solution returned to the pad is estimated. This mass does not include metal recirculated in the barren solution. |
| total_recoverable_metal_placed (oz,g) | Total recoverable metal in model. This value is used to check that the amount of recoverable gold loaded in the model is the same as that indicated in the placement schedule. |
| total_unrecoverable_metal_placed (oz,g) | Total unrecoverable metal in model. |
| total_extractable _metal_remaining (oz,g) | Total recoverable metal remaining in model. |
| metal_applied_to_pad (oz,g) | The total accumulating mass of metal entering the model over period of time (barren solution). |
| solution_metal (oz,g) | The mass of metal in the leach solution contained in the model over period of time. |
| flowing_solution_metal_inventory (oz,g) | The mass of metal in the flowing leach solution contained in the model over period of time. The value is equal to 0 if the moisture content is below the field capacity. |
| stagnant_solution_metal_inventory (oz,g) | The mass of metal in the flowing leach solution contained in the model over period of time. The value can also be expressed as the difference of the total solution inventory and the flowing solution inventory. |
| Total_metal_remaining (oz,g) | The total accumulating mass of metal remaining in the model over period of time. |
Ore Property Output Types
| Data Selection | Cumulative | Daily | Monthly | Weekly |
|---|---|---|---|---|
| Metal_realized | Data | Delta(t) | Total | Total |
| Flowing_solution_metal_inventory | N/A (display daily) | Data | MEV | MEV |
| Stagnant_solution_metal_inventory | N/A (display daily) | Data | MEV | MEV |
| Metal_applied_to_pad | Data | Delta(t) | Total | Total |
| Net_metal_produced | Data | Delta(t) | Total | Total |
| Solution_metal | N/A (display daily) | Data | MEV | MEV |
| Total_metal_placed | Data | Delta(t) | Total | Total |
| Total_recoverable_metal_placed | Data | Delta(t) | Total | Total |
| Total_unrecoverable_metal_placed | Data | Delta(t) | Total | Total |
| Total_metal_remaining | N/A (display daily) | Data | MEV | MEV |
| Total_extractable_metal_remaining | N/A (display daily) | Data | MEV | MEV |
Solution
Solution Property Definitions
| Property | Definition |
|---|---|
| volume_applied (gal, m3) | The total cumulative volume of solution entering the model over period of time. |
| volume_drained (gal, m3) | The total cumulative volume of solution exiting the model over period of time. |
| solution_inventory (gal, m3) | The volume of leach solution contained in the model at any period of time. This should equal the flowing and stagnant solution inventory at any time period. |
| flowing_solution_inventory (gal, m3) | The volume of flowing leach solution contained in the model at any period of time. |
| stagnant_solution_inventory (gal, m3) | The volume of stagnant leach solution contained in the model at any period of time. |
| applied_flow_rate (gpm, L/m2-hr) | The applied leach solution rate entering the pad at any period of time. |
| draining_flow_rate (gpm, L/m2-hr) | The draining leach solution rate leaving the pad at any period of time. |
Solution Property Output Types
| Data Selection | Cumulative | Daily | Monthly | Weekly |
|---|---|---|---|---|
| Leaching Cells | N/A (display daily) | Data | Average | Average |
| Precip_infiltration [gpm] | N/A | Data | Average | Average |
| Precip_runoff [gpm] | N/A | Data | Average | Average |
| Cumulative_precip_infiltration [gal] | Data | Delta(t) [gal/day] | MEV | MEV |
| Discharge_flow_rate [gpm] | N/A | Data | Average | Average |
| Cumulative_discharge_flow [gal] | Data | Delta(t) [gal/day] | MEV | MEV |
| Cumulative_precip_runoff [gal] | Data | Delta(t) [gal/day] | MEV | MEV |
| Active_cells | Data | Delta(t) [cells/day] | Average | Average |
| Total_blocks | Data | Delta(t) [blocks/day] | Total | Total |
| Tns_stacked | Data | Delta(t) | Total | Total |
| Solution_inventory [gal] | N/A (display daily) | Data | MEV | MEV |
| Volume_drained [gal] | Data | Delta(t) [gal/day] | MEV | MEV |
| Draining_flow-rate [gpm] | N/A | Data | Average | Average |
| Applied_flow_rate [gpm] | N/A | Data | Average | Average |
| Volume_applied [gal] | Data | Delta(t) [gal/day] | MEV | MEV |
| Flowing_solution_inventory [gal] | N/A (display daily) | Data | MEV | MEV |
| Stagnant_solution_inventory [gal] | N/A (display daily) | Data | MEV | MEV |
| Cumulative_precipitaion [gal] | Data | Delta(t) [gal/day] | MEV | MEV |
| Average_precipitation_rate [gpm/ft2] | N/A (display daily) | Data | Average | Average |
| Design_num_blocks | N/A (display daily) | Data | Average | Average |
11.7 CutterResult Recovery Model Properties:
| Name | Summary |
|---|---|
| midx | Block center point X coordinate (ex. 6501625) |
| midy | Block center point Y coordinate (ex. 2182875) |
| midz | Block elevation (ex. 2930) |
| z | Block elevation (ex. 2930 = midz) |
| type | What kind of shape it is (always will be fill for modeling) |
| pn | Property used to sort, combination of pn_gid_z (ex. S3_L1_C6_5x6_2930_) |
| gy | Numbered grid coordinate Y (ex. 7) |
| gx | Numbered grid coordinate X (ex. 5) |
| gid | Unique property for each block, combination of gx and gy (ex. 5x7) |
| seq | After sorting, we assign numbers 1 – n where n represents the number of blocks (ex. 11450) |
| swell | Used for Ton calculation (should be 1 for most models without Opencontour ) |
| on | Date when the block receives solution, used with ‘lt’ to decide when it turns |
| la | Layer type (ex. cr, negligible) |
| lt | Leach cycle, Days receiving solution (ex. 75) |
| dens | Block density, used in ton calculation (ex. 0.057) |
| tns | Tons of block = vol x dens (ex. 1425) |
| area | Area of the block = width x height (ex. 2500.00) |
| vol | Volume of the block = vol x area x bench height (ex. 25000) |
| fi | Phase name of the block, assigned through the Filler layer (ex. S3_L1_C6) |
| cut_fill_num | Filler number from layer menu, (ex. 7) |
| dir | Direction of stacking of the pad, assigned through the layer menu (ex. 180) |
| ow_min | Type of ore type (‘ow’) received minimum (ex. 0.5) |
| ow_max | Type of ore type (‘ow’) received maximum (ex. 10000) |
| au | Grade of gold in block (ex. 0.027 g/t) |
| ag | Grade of silver in block (ex. 0.352 g/t) |
| imc | Initial Moisture Content (ex. 0.08) |
| sseq | Stacking sequence, used with direction (ex. 3797) |
| ow | Ore type, imported from mineplan (ex. 70) |
| pm | Date block was placed (ex. 44884) |
| ltp | Leach type (ex. 3) |
| ultimate | Ultimate from extraction curve (ex. 0.699) |
| on_seq | Sorted number used for variance turning blocks on/off (ex. 9371) |
| aum1 | Metal placed initially (ex. 1199.5 g) |
| aurp1 | Block recoverable metal placed beginning of model (ex. 839.65 g) |
| aur1 | Block metal remaining beginning of model (ex. 458.41 g) |
| auer1 | Block extractable metal remaining beginning of model (ex. 98.56 g) |
| aufi1 | Block flowing solution metal inventory at beginning of model (ex. 5.7 g) |
| ausi1 | Block stagnant solution metal inventory beginning of model (ex. 0.303 g) |
| aux1 | Block extraction beginning of model (ex. 0.618 g) |
| aum2 | Metal placed end of time =aum1 (ex. 1199.5 g) |
| aurp2 | Block recoverable metal placed end of model = aurp1 (ex. 839.7 g/t) |
| aur2 | Metal remaining at end of model run (ex 58.4 g/t) |
| auer2 | Total extractable metal remaining at end of model (ex. 98.5 gt) |
| aufi2 | Flowing solution metal at end of model (ex. 0 g/t) |
| ausi2 | Stagnant solution metal at end of model (ex. 0.303 g/t) |
| aux2 | % Metal extracted at the end of the model run (ex. 0.617) |
| flow_out_bottom | Flow out of the bottom of block at the end of the model run |
| days_leaching | Number of days leaching, includes cut point and slope calculations |
| moisture_content | Moisture content of last day of model run (ex. 0.139) |
| r_ar | Reference application rate (ex. 0.005) |
| pm2 | Date placed block above (ex. 47785) |
| pm3 | Difference between date placed above and current blocks date place (ex. 12) |