Tailings Dams

[Bamps21]

[Bamps21]

https://www.newcrest.com/sites/default/ ... 202021.pdf
The tailings dams Tsf7 57m high 208m cubic metres currently stored in 2021
Planned 250m cubic metres

[Bamps21]

This is where the paste fill is coming from

[Bamps21]

TSF8
https://www.newcrest.com/sites/default/ ... SF%208.pdf
Thanks to Paddy

[Bamps21]

30th January

[Bamps21]

bd0865b2-d8c6-4969-a993-a205c3bdf6a8.jpeg (16.54 KiB) Viewed 14063 times

4th February
top arrow looks like infilling operation , bottom arrow looks like crack being filled in

[Bamps21]

This is an image from 2023 the crack at 12 O’clock can be seen quite clearly

[Bamps21]

Plans for Telfer 2002 pre tailings lake

[@ianbow]

Great information as always, Bamps. Many thanks

[Bamps21]

Latest image of the tailings dams shows the crack has been rectified but it’s showing a lot of moisture towards the 10 O’clock position

[Bamps21]

Looks like a lot more water in the tailings.
Have they restarted processing?

[jecsggp]

Thanks, Bamps. If they have been working in that 'wet' area to fill the crack they have probably created lower levels than the rest of the ailings and any inflows would tend to move to fill that area with water/solids to level it all up. Could just be adding water to pressure test the repair?

IMG_6456.jpeg
Looks like a lot more water in the tailings.
Have they restarted processing?

[Shinybits]

They haven’t actually repaired anything as yet.

They have restarted the plant, with permission from DMIRS (state govt mines regulator), and have the capacity to load one particular quadrant of TSF7 with 3Mt of material. On this basis they are only running train 1, which is the train that processes a mix of underground and pit dirt, and expect to able to run until roughly May for this volume. At this point they plan to shut down the whole processing plant again until repairs are complete on the dam wall, which will hopefully be around August, then it will be both trains full steam ahead, with a great deal of long overdue maintenance under its belt that in many cases is too time consuming to be carried out within the timeframes of a normal maintenance shut.

[FuttBucker]

Useful timing for full capacity coming on stream then!

[Shinybits]

It is apparent that the quadrant of the tailings dam currently being used at Telfer for train one deposition has a greater capacity than originally estimated, (I’m referring to the section currently in use before a final determination is made regarding repairs to the crack and the sinkhole on the other side).

This is good news as it means they can run train one for longer prior to shutting it down whilst dam repairs are completed.

Given the (still) finite capacity however, they are running the process slower than usual and are even using some of the copper cleaner flotation cells on train 2 from the Jamos to maximise recovery.

There is a plane or two full of contractors arriving this week to carry out maintenance works on train 2 while most of it is not being used, and the train 2 feed belts, SAG mill, cyclone feed pump and ball mill have all been operated (the mills on inch, not full speed), just to ensure the cobwebs are kept at bay, so in due course it should be full steam ahead for the whole plant. I’m sure the time will fly by.

[Bamps21]

A lot of rain recently everywhere looks wet

[Shinybits]

Yep 50mm in about 2 hours late Wednesday afternoon local time. Not good for the dam, wastes capacity otherwise earmarked for tailings use. Still, wet season should be petering out, by mid April it’s generally dry until Christmas.

Currently very humid however, not nice.

[jecsggp]

Is this unusually heavy rain for this time of year? I had assumed the enclosed aquifer we are dewatering at Havieron was archaic water. I don't know if Havieron is experiencing the same heavy weather, but can I assume the heavy rain we are experiencing will not affect the volume in that aquifer in the short term?

[Bamps21]

The top 2 aquifers refill the lower one is confined.
The Lower aquifer has an impermeable layer above it and is not open at surface like the other 2

[Shinybits]

Is this unusually heavy rain for this time of year? I had assumed the enclosed aquifer we are dewatering at Havieron was archaic water. I don't know if Havieron is experiencing the same heavy weather, but can I assume the heavy rain we are experiencing will not affect the volume in that aquifer in the short term?

Whilst the March total so far is above average, I wouldn’t call it unusual as the wet season there is generally January to March, in practice. The long term average for the whole of April is under 20mm, so it’s pretty much dry until December or January from the end of this month.

Haveiron is only 40 odd kms away so I’d expect by and large the same rainfall there. The rainfall is relatively low when compared to that experienced further north in the Kimberley, but Telfer’s heat in December and January is debilitating, imagine working in 45 to 47 degrees for days on end, there is a website that details the hottest (and coldest) 15 locations on the planet over the preceding 24 hours, and it is not uncommon for telfer to be in at least the top three or four, if not at the top of the list. Indeed Marble Bar, the nearest town, boasts a world record of 161 consecutive days of temperature over 100*F (37.8*C).

Hopefully the seismic testing will be finished and analysed sooner rather than later and a plan will be formulated to carry out permanent repairs on the dam walls and sinkhole. Whether Newmont keep it, sell it or close it, it has to be repaired no matter what, so it’s important to get it right.

To close Telfer, the closure and rehab costs would unlikely to get you change out of $600M I’d think, and given that new owner would become responsible for this cost in the future, would I be cynical to assume that an interested party could probably buy telfer for a dollar? Or maybe a nice bottle of scotch. Actually, given it’s Australia, that would be a slab of coldies