Underground Priorities

The combination of precedences and priorities determines the mining sequence. Precedences define which headings or locations must be mined before other headings or locations are available to be mined. Priorities determine how resources are allocated to development headings, and how resources are allocated to production locations when multiple locations are available and quality or material ratio targets have not been defined.

If quality or material ratio targets have been defined the mining sequence is chosen to best achieve the targets. It is rare that quality or material ratio targets are used in underground scheduling. When quality and material ratio targets are not set the use of priorities is important to control the mining sequence.

Four priority data grids exist for Underground scenarios. You use the Initial development priorities data grid to define the priority of the development headings at the start of the schedule. You use the Initial production priorities data grid to define the priority of the production locations at the start of the schedule. You use the Development priority changes data grid to define the changes to the priority of development headings along the headings at different dates, or after events have occurred, during scheduling. You use the Production priority changes data grid to define the changes to priority of production locations at different dates, or after events have occurred during the schedule.

Note: If you define priorities in the Development priority changes or Production priority changes data grids that are effective from the start of the schedule, they override the priorities you set in the Initial development priorities or Initial production priorities data grids.

You can define initial development and production priorities using the data grids or you can use the spreadsheet view by clicking the Edit in spreadsheet view icon.

Note: Spreadsheet view for the Initial development priorities and Initial production priorities data grids are temporary. When you click OK or Cancel, the values in the spreadsheet are saved as text in the data grid. This means that any additional data and the formulas you used to create the priorities are not maintained.

You can define the development and production priority changes in the data grid or you can use the spreadsheet view. To access the spreadsheet view, select Spreadsheet > Enable Spreadsheet Views, and then select the Priorities spreadsheet. When the Priorities spreadsheet is enabled, it replaces the Development priority changes and Production priority changes data grids.

Columns in the Initial Development Priorities Data Grid

Column	Description
Active	Selected: The priority rule is applied to the heading. Cleared: The priority rule is not applied to the heading. Tip: When you clear the Active check box, you make the priority rule ineffective without deleting the rule.
Heading	The name of the heading to which the priority is applied.
Priority	The value of the priority for the heading. Values can be any number greater than zero. The lower the number the higher the priority.
Comments	Any notes you want to record about the priority.

Columns in the Initial Production Priorities Data Grid

Column	Description
Active	Selected: The priority rule is applied to the locations. Cleared: The priority rule is not applied to the locations. Tip: When you clear the Active check box, you make the priority rule ineffective without deleting the rule.
Location	The name of the location to which the priority is applied.
Priority	The value of the priority for the location. Values can be any number greater than zero. The lower the number the higher the priority.
Comments	Any notes you want to record about the priority.

If you want to define more than one level of priority in either the Initial development priorities or Initial production priorities data grids, you can use the Settings icon at the top of the Initial development priorities and Initial production priorities data grids to create additional columns for different levels of priorities. When you click the Settings icon the Priority Levels form appears, which displays the Priority levels data grid.

Columns in the Priority Levels Data Grid in the Priority Levels form

Column	Description
Name	The name of the priority level. The name of the first priority level is set by default and cannot be changed. You can change the names of subsequent priority levels. Note: You can create a total of ten levels of priorities.

Columns in the Development Priority Changes Data Grid

Column	Description
Active	Selected: The priority rule is applied to the headings. Cleared: The priority rule is not applied to the headings. Tip: When you clear the Active check box, you make a priority rule ineffective without deleting the rule.
Headings	The heading or headings to which the priority is applied. Tip: You can use wildcards to specify more than one heading. To specify the headings using the Wildcard Expression Builder, use the Ellipsis button.
Resources	The name or names of the resources to which the priority is applied for the heading. Tip: You can use wildcards to specify more than one resource. To specify the resources using the Wildcard Expression Builder, use the Ellipsis button.
Date/event	The date on which the priority change is applied to the heading or headings. You can use a calendar date or an event. The date or event plus the Delay determines the actual start date. You use the Calendar button to select a date from a calendar. You use the Ellipsis button to select an event using the Event Builder. You can use events to change the priority at a specified length along a heading.
Delay	The delay after the Date/event before the priority change is applied to the heading or headings. The default delay is 0. The delay can be any positive number. Note: Part days are expressed as decimals, not in HH:MM:SS format. Usually, delays are used when the Date/event is an event, and the actual date that the event occurs is not known until the schedule is run.
Priority	The value of the priority for the heading or headings. Values can be any number greater than zero. The lower the number the higher the priority.
Comments	Any notes you want to record about the priority.

Columns in the Production Priority Changes Data Grid

Column	Description
Active	Selected: The priority rule is applied to the locations. Cleared: The priority rule is not applied to the locations. Tip: When you clear the Active check box, you make the priority rule ineffective without deleting the rule.
Locations	The location or locations to which the priority is applied. Tip: You can use wildcards to specify more than one location. To specify the locations using the Wildcard Expression Builder, click the Ellipsis button.
Resources	The name or names of the resources to which the priority is applied for the location. Tip: You can use wildcards to specify more than one resource. To specify the resources using the Wildcard Expression Builder, click the Ellipsis button.
Date/event	The date on which the priority change is applied to the location or locations. You can use a calendar date or an event. The date or event plus the Delay determines the actual start date. You use the Calendar button to select a date from a calendar. You use the Ellipsis button to select an event using the Event Builder.
Delay	The delay after the Date/event before the priority change is applied to the location or locations. The default delay is 0. The delay can be any positive number. Note: Part days are expressed as decimals, not in HH:MM:SS format. Usually, delays are used when the Date/event is an event, and the actual date that the event occurs is not known until the schedule is run.
Priority	The value of the priority for the location or locations. Values can be any number greater than zero. The lower the number the higher the priority.
Comments	Any notes you want to record about the priority.