Decline progress

[Bottle Rocket - Liam]

New Thread for updating the decline process

[RationalAssessor]

[RationalAssessor]

Using data from RNS Dated 8 Sep 22. Data to 31 Aug

[zoros]

I'm seeing approx 200m in 5 weeks. This might now be the steady state (as per the Byrnecut webpage - 154m/month).
If that is the case and assuming a decline of 3000m (not the original 2600m advertised at the start), then we have 2300m remaining @ 150m/m makes an ETA at the motherlode at or around October 2023. [IMO].
Z.

[RationalAssessor]

Updated from the NCM Exploration results of 27 Oct 2022.

[zoros]

1520m as of 18th January 2023.
920m as of 12th October 2022.
600m in 100 days.
ETA motherlode: July 2023.

Z

[RationalAssessor]

And here it is, the highlight of Strudel's weekend. A decline progress chart updated with the info from the latest exploration report.

[RationalAssessor]

So, on 27 Feb, NCM released a presentation which indicated that the decline had progressed to around 1800 metres. Below are the updated charts on overall Decline Progress and the Rate of Progress.
Please take note of Bamps LSE post which clearly shows that there is plenty of further work to be done between the completion of the decline and reaching the orebody. Additionally, further permits will need to be approved once the decline is complete - I am assuming/hoping that these permits have already been submitted. At the current rate, I would expect that the decline will be complete toward the end of July.

[RationalAssessor]

Updated to reflect the 16/3 results.

[RationalAssessor]

Updated to reflect the information contained in the RNS of 27 April 2023.

[RationalAssessor]

Adjusted to show total runnel length as 3250M. Comprising 2600 for decline plus a further 25% (650M) for ancillary tunneling for passing bays and ore storage..

[Bamps21]

Can I ask where the 3250m total has come from?
I was under the impression it was 3600 from the original design.

[RationalAssessor]

Bamps - Thanks.

When I originally created the graph, I calculated that the decline would need to be 2800M to reach 400M below surface at a rate of 1 in 7. Early on, Zoros advised me (below) that the decline length should actually be 2600M - graph was duly modified.
Subsequently, it has become obvious that all of the ancillary tunnels (passing bays and ore storage) are being included in the tunneling reports so 2600M was understating the target.
From the last but one exploration report, I estimated that there would be an additional 400M on top of decline so total was changed to 3000M.
This most recent report has given us more insight that the ancillaries are around 25% on top of the decline length.....hence 3250M

Clearly, it's a bit of a moving feast.

IMO, the decline progress chart was just a bit of a visual representation on how we were progressing and how the rate might change as we moved through the various layers.......it might also give us an insight to when we might need the further approvals to continue from the bottom of the decline into the mine structure proper.

ATB RA.

[Bamps21]

Hi RA
In the original mining plan I believe the Decline length was 2760m plus 900m of vents and drives.
The 2,600m could have come about by the steepening of the gradient slightly, I don’t remember it being published.
The 900 could have changed but if it has shortened then some vents may have been removed.
All rather confusing and not well explained by the company/ Newcrest.

[Bamps21]

This is my thoughts on the Decline

The actual Decline length has always brought up the question what is it?

Back to basics
420m to top of ore less 23m for box cut = 397m
Is it a 14% or 1:7 gradient?
14% = 1:7.143

397 x 7.143 = 2,835m
397 x 7 = 2,779m

Permission only to 400m
Less 23m
377m x 7.143 = 2,693m
377 x 7 = 2,639m

From the graphics the Decline turns to the right about 140m-150m from the ore body.
This tallies up roughly with the difference between the 400 & 420 lengths.
, ie 2,693 and 2,835
The turn right is where the Exploration Decline ends.

I’m still confused where the 2,600 has come from and the 25% ancillary work
I believe the ancillaries to be 900m not 650m , this was mentioned in the original plans.
The ventilation shafts will be around the 420m length plus if a second shaft is installed by the first one then that’s at least another 120m.
The mining plan has changed but the vent length can’t alter
When I first saw the 900m I thought that looks light if it includes the vent lengths.

Judging by the lengths I’ve worked out 2,800 looks to be getting to the ore and 2,660 looks to be getting to the turn right, plus 900m ancillaries.

[RationalAssessor]

Looks like we have a much better estimate and reference for the amount of tunneling required for the decline. Thanks to Bamps and Paddy under the Havieron subject.
Below are the modified graphs with 3694M being the overall tunneling target.

[RationalAssessor]

Update from today's RNS. Decline greater than 1700M with overall tunneling of greater than 2400M.
My best guess is that decline may be completed just in time for Christmas. Then move on to develop the mine structure.

[RationalAssessor]

Update to graphs following NCMs ASX announcement on 25th July. Decline now 2510M.

[RationalAssessor]

Updated using information from 12 Aug RNS.

[RationalAssessor]

Updated from SD pres on 13 Sep where he advises progress is now at 2692 as at 1 Sep.