Ann: RIU Resurgence Conference Presentation, page-13

The update was given in the RIU presso. 195m actual vs 160 forecasted (25m over schedule). Now that Byrnecut are in hard rock and assuming they are using sandvik 16/10 split feed jumbos which use 4.9m steels (4.5m actual advance per cut) they will be punching this decline in quick!

Single heading jobs like these normally fire each cut independently so as soon as the cut is;
1) mesh and bolted (2 hours),
2) bogged and hauled (2 hours),
3) Bored using 4.9m steels (4.5m cut length) (2 hours),
4) Charging time (1 hour)
1) delays, breakdowns, tramming, re-entries etc (2 hours)

Total time to turn over a 4.5m advancement is 9 hours - this is pretty quick rate considering 6mH x 6mW decline profile.
*assuming they remain in hard rock and don't have any issues with dewatering it can be done

Looking at the photo in the presso you can see Byrnecut have used fibrecrete (FRS) for additional support in the first 160m, this does delay cycle times as you have to wait for FRS curing times (up to 4 hours per cycle). Generally, when you are in hard rock as stated in the presso the requirement for fibrecrete goes away (hence not included in the 9 hours cycle times).

720 hours in a month (720 hours / 9 hour cycle times) = 80 cuts per month
80 cuts x 4.5m cut length = 360m advance rate per month

The 360m is lateral development, decline gradients are built on 14 degrees grade or 1:7 (for every 1 vertical m you develop 7 horizontal) which (in simple terms) is 51m vertically per month.

The portal RL is 1550 and the top of the ore body (going off the slide in presso) is 1350 RL which represents ~200m vertically....4 months of mining to the top of the ore body.

Byrnecut are the best in the business (trust me on that).

For me the hold up will be punching in the RAR (return air raise) which controls the primary vent circuit. The inter level spacing RAR's are fine (especially if Byrnecut are doing it) its the big one I will be watching for.... Not sure if RUC or Raising Australia are punching the longer vertical raise in.