berrima colliery - closure working group meeting #3 · environmental protection licence/ mine...

Berrima Colliery -

Closure Working

Group

Meeting #3

Berrima Colliery, Medway, 11 February 2019

>Welcome

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Agenda

1. Welcome and Apologies

2. Pit top inspection

3. Review of minutes & actions

4. Estimates of Iron removed since commencement of trials

5. Water Quality Trends and Macroinvertebrate Update

6. Bulkhead Seals Update

7. EPL/MOP Updates

8. Loch Catherine Update

9. Communications Plan

10.General business

11.Next meeting


Welcome - CWG Representatives, Apologies & Guests

● Boral - Fabio Colusso, Greg Johnson, David Spears, Chris Maher

● Resource Regulator - Greg Kininmonth,

● Environment Protection Authority - William Dove, Andrew Couldridge

● WaterNSW - Ravi Sundaram

● Wingecarribee Shire Council - Barry Arthur

● Western Sydney University - Dr Ian Wright, Dr Jason Reynolds (Guest)

● Community - Clive West, Alan Lindsay, Graham Kelly, Ray Nolan, Julian Brophy (phone)

● Independent chair - Brad Mullard

● Minute taker – Rob Byrnes


Pit Top Inspection

Safety requirements - David/Chris


Pit Top Inspection


Review of Minutes – suggested amendments & review of actions


Terms of Reference


Estimated Metals retained within mine 15 Feb 2018 - 26 Nov 2018

Iron - 8956 kg

Manganese - 1834 kg

Nickel - 32.5 kg

Zinc - 72 kg


Surface Water Performance Monitoring Update - Report dated 31 October 2018


Surface Water Performance Monitoring Update - report dated 31 Oct 2018

Wingecarribee River Flow - Very low flow (before recent rain and releases), mixing becomes non-existent in very low flows, mine

discharge accounted an average of 30% of stream flow during 2018

2018 Annual report due end of February

2019 Study note: Optimistic that with the improved water quality of discharge waters, recent flushes of the river from storm events and

WaterNSW releases coupled with reduced discharges during the bulkhead seal recharging we should see some improvement in stream

health over the coming 6-12 months.


Surface Water Monitoring Update

● pH - of mine water averaging 0.5 below long term

average. Not appearing to impact water

downstream.

● Conductivity - higher conductivity causes an

increase within and beyond mixing zone,

increase of 200us/cm, it is generally below

500us/cm which is considered fresh and non-

saline

● Sulphate - Remains relatively constant

downstream, little fluctuation, generally below

100mg/L, which is considered environmental

range



● Iron - Drops rapidly, generally follows upstream

sites.

● Mg - Decreases rapidly through mixing zone.

Similar to historical situation, all below ANZECC

95% default of 1.9mg/l



● Nickel & Zinc - Decreases rapidly within the

mixing zone meeting ANZECC 95% ecosystem

protection values of 0.011 Nickel and 0.008 Zinc

at Biloela


Discharge Quality Update - Volumes

● Additional pumping ceased in

October to allow bulkhead works to

commence

● Recharging rate appears to be

slowing with pumping now

intermittent


Treatment Trial Water Quality Trends - pH & EC

● pH is relatively constant and

within licence range of 6.5 -

8.5

● Conductivity trending down

towards 2015 levels


Treatment Trial Water Quality Trends - Iron and Manganese

● Iron and Manganese - returning

to 2015 levels

● Close to 9t or Iron and 2t of

Manganese prevented from

entering river

● Precipitates remain within the

limestone trench and goaf

● See samples of limestone from

treatment bed


Treatment Trial Water Quality Trends - Nickel and Zinc

● Nickel and Zinc has returned to

2015 levels


Water Quality Trends along the treatment path - Iron and Sulphate examples

● 400 D12 Sump - Pump pick up

location

● 400 C8 - After aeration, treatment

through lime bed and filtered through

goaf

● Adit Discharge - V - Notch sample

Iron - Level remains elevated from sump.

Treatment significantly reduces level.

Sulphate - Levels are decreasing. Treatment

system assisting binding with limestone to

form gypsum but only minimal.


Macroinvertebrate study update - January 2019 Report

● In general, impacts from discharge were observed

downstream at Site 3 (300m downstream) and Site 4

(1000m downstream) in all three survey periods (March,

June and September 2018) with no obvious impacts at

sites further downstream.

● Impacts included: reduction in abundance, taxonomic

richness and EPT, and change in macroinvertebrate

assemblage structure.

● There were some small improvements in EPT, taxonomic

richness at Site 3 and 4 in September 2018 and became

more similar to reference sites.

● However this is difficult to relate to any improvements due

to water quality treatment. Improvements in water quality

were offset by extensive low flows of the Wingecarribee

River and associated water quality.

● Iron precipitate is the likely mechanism affecting

macroinvertebrates, and was the most improved

parameter observed within the mine after improvements in

water treatment practices.

● With the longer term implementation of these measures it

is likely that further improvements will be measurable in

future monitoring.


Interim Sealing Plan Update - Location in respect of workings


Bulkhead Seal installation update


Environmental Protection Licence/ Mine Operations Plan Updates

EPL 608 - Varied in November to amend report submission dates

MOP - Update to MOP to be submitted in April 2019 to reflect Loch Catherine sealing options.

The Loch Catherine Mine was closed in 1959 and although most of the original infrastructure has been removed, the four

entries were never sealed. The permanent sealing of mine entries is a requirement of CCL 748 and the Mining Act 1992.

The type of seal proposed has been the subject of discussions with relevant government agencies for over 10 years. The

location of the entries at the base of an unstable cliff face presents significant safety risks.


Loch Catherine Update


Loch Catherine Update

Access to the adits via the former drift was reinstated as per the approved Stage 1 MOP in

December.


Communication Plan - Update

Master Animation is proposed as a next stage in community engagement, one 2-

3-minute master video animation [shareable format] will be produced to visualise

and explain the current treatment trial and proposed closure approach.

The video will outline:

1. The history of the Berrima Colliery and the surrounding environment

2. The process behind closing the Colliery

3. An overview of the testing approach and results

4. The current approach to water treatment

5. Expectations for the future management of the Colliery and surrounding

environment

6. Boral’s commitment to a best practice approach

Master Animation is proposed as a next stage in community

engagement, one 2-3-minute master video animation [shareable

format] will be produced to visualise and explain the current

treatment trial and proposed closure approach.

The video will outline:

1. The history of the Berrima Colliery and the surrounding

environment

2. The process behind closing the Colliery

3. An overview of the testing approach and results

4. The current approach to water treatment

5. Expectations for the future management of the Colliery and

surrounding environment

6. Boral’s commitment to a best practice approach


General business


Next meeting date

Due to bulkhead seals, recharging of mine and minimal discharge

Proposing 6 months time - August 2019, will provide an update to members of CWG on site

activities in May 2019.

Location – TBA

berrima colliery - closure working group meeting #3 · environmental protection licence/ mine...

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