Longwall 411 to 418 Subsidence Management Status...
Transcript of Longwall 411 to 418 Subsidence Management Status...
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Longwall 411 to 418
Subsidence Management Status
Report
Springvale Colliery
July 2016
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TABLE OF CONTENTS 1. INTRODUCTION .............................................................................................................................. 4
2. PURPOSE AND SCOPE ................................................................................................................. 5
3. FACE POSITION OF THE LONGWALL ......................................................................................... 5
4. MANAGEMENT ACTIONS AND CONSULTATION ....................................................................... 7
4.1. Management Actions ............................................................................................................... 7
4.2. Consultation ............................................................................................................................. 7
5. OBSERVED IMPACTS AND NOTIFICATIONS .............................................................................. 9
6. MONITORING PROGRAM .............................................................................................................. 9
6.1. Subsidence............................................................................................................................. 11
6.2. Rainfall ................................................................................................................................... 12
6.3. Groundwater Monitoring Program .......................................................................................... 13
6.3.1. Methodology ................................................................................................................... 13
6.3.2. Groundwater Level Results ............................................................................................ 16
6.3.3. Groundwater Quality Results ......................................................................................... 29
6.4. Surface Water Monitoring Program ....................................................................................... 31
6.4.1. Methodology ................................................................................................................... 31
6.4.2. Surface water flows ........................................................................................................ 32
6.4.3. Surface Water Quality .................................................................................................... 36
6.5. Fauna Monitoring Program .................................................................................................... 40
6.5.1. Methodology ................................................................................................................... 40
6.5.2. Results ........................................................................................................................... 40
6.6. Flora Monitoring Program ...................................................................................................... 43
6.7. Native Species diversity ......................................................................................................... 44
6.7.1. THPSS MMP .................................................................................................................. 44
6.7.2. 2009 EMP ....................................................................................................................... 46
6.8. Eucalypt Recruitment ............................................................................................................. 47
6.8.1. THPSS MMP Sites ......................................................................................................... 47
6.8.2. 2009 EMP ....................................................................................................................... 48
6.9. Species Condition scores ....................................................................................................... 48
6.9.1. THPSS MMP Sites ......................................................................................................... 48
6.9.2. 2009 EMP ....................................................................................................................... 49
6.10. Non Live ground cover ....................................................................................................... 50
6.10.1. THPSS MMP Sites ......................................................................................................... 50
6.10.2. 2009 EMP ....................................................................................................................... 51
6.11. Establishment of non-native weeds ................................................................................... 51
6.11.1. THPSS MMP Sites ......................................................................................................... 52
6.11.2. 2009 EMP ....................................................................................................................... 52
6.12. Conclusions ........................................................................................................................ 52
6.13. Photo-monitoring ................................................................................................................ 53
6.13.1. Surface Features ............................................................................................................ 53
6.13.2. Newnes Plateau Shrub swamps .................................................................................... 57
7. ADEQUECY, QUALITY AND EFFECTIVENESS ......................................................................... 63
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8. PROPOSED MANAGEMENT ACTIONS ...................................................................................... 63
9. CONCLUSIONS ............................................................................................................................. 63
Appendices Appendix 1 Plans
Appendix 2 Groundwater and Surface Water Report
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1. INTRODUCTION
Springvale Colliery is an existing underground coal mine producing high quality thermal coal for both
domestic and international markets. It is located 15 kilometres to the northwest of the regional city of
Lithgow and 120 kilometres west-northwest of Sydney in New South Wales.The regional locality of
Springvale Mine is shown on Figure 1.
Figure 1 Regional Locality
This Subsidence Management Status Report (SMSR) fulfils the requirement of Condition 14 of the
Springvale Mine SMP Approval Conditions for Longwalls 411 to 418. This SMSR covers the
monitoring period between the 1st of February and the 31
st of May 2016, with monitoring results
available for this period presented in this report. Some results collected during the reporting period
may not be included due to the time associated with analysis and presentation of results following
field work. These results will however be included in future reports.
Regulatory requirements applicable to the SMP are outlined in Section 2.
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2. PURPOSE AND SCOPE
The purpose of this document is to report in accordance with and comply with the requirements of
Condition 14 of the Springvale Mine SMP Approval. Table 1 summarises the requirements of this
Condition and where they have been addressed in this document.
Subsidence Management Status Report Requirements Table 1.
Condition
Condition Requirement Section
Addressed
17a The current face position of the panel being extracted; 3
17b A summary of any subsidence management actions undertaken by the leaseholder; 4
17c A summary of any comments, advice and feedback from consultation with
stakeholders in relation to the implementation of this approval (including the
preparation, implementation and review of plans, programmes, reports or strategies
required by this approval) undertaken or received and a summary of the
leaseholders response to the comments, advice and feedback given by the
stakeholders;
4
17d A summary of any observed and/or reported subsidence impacts, incidents, service
difficulties, community complaints, and any other relevant information reported to
the leaseholder and a summary of the leaseholders response to these impacts,
incidents, service difficulties and complaints
5
17e A summary of subsidence development based on monitoring information compared
with any defined triggers and/or predicted subsidence to facilitate early detection of
potential subsidence impacts;
6
17f A summary of the adequacy, quality and effectiveness of the implemented
management processes based on the monitoring and consultation information
summarised above; and
7
17g A statement regarding any additional and or outstanding management actions to be
undertaken or the need for early responses or emergency procedures to ensure
adequate management of any potential subsidence impacts due to longwall mining
8
This report also provides the opportunity for relevant stakeholders to provide feedback regarding the Springvale Mine monitoring and management measures as required under Condition 9.
3. FACE POSITION OF THE LONGWALL
Extraction of Longwall 418 commenced on the 22nd
of October 2015 and was completed on the 27th of
May 2016 with a total retreat of 2487m. As at the 31st of May 2016 mining had not yet commenced in
Longwall 419.
Longwall locations and the face position with reference to subsidence monitoring lines are shown
below in Figure 2.
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Figure 2 Face Position and Subsidence Monitoring Locations
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4. MANAGEMENT ACTIONS AND CONSULTATION
4.1. Management Actions
There has been no management actions required during the reporting period.
4.2. Consultation
The contact details for Springvale personnel responsible for environment management and
community relations, along with details for community complaints and enquiries have been provided
in Table 2.
Primary Contact Springvale Colliery Table 2.
Contact Position Contact Details
Primary Contacts
Jacques Le Roux Mine Manager T: (02) 6350 1613
F: (02) 6355 1502
Catherine Suggate Environment and
Community Co-ordinator
T: (02) 6350 1672
F: (02) 6355 1502
Community Enquiries/Complaints
Springvale Enquiries and Community Complaints T: (02) 6350 1640
During the reporting period the following consultation was undertaken:
Stakeholder correspondence summary Table 3.
Date From To Method Details
29/03/2016 Springvale DRE Letter MOP 2015 – 2022
Submission
03/05/2016 DRE Springvale Email SMSR Reports
28/10/2015 Springvale DRE Letter EMP revision
Correspondence
26/11/2015 Centennial DPE
DRE
OEH
LCC
Site visit Newnes Plateau
Inspection
22/12/2015 Centennial DRE Letter THPSS MMP trigger
Notification
With reference to correspondence from DRE an explanation and update is provided below.
Correspondence DRE Table 4.
Topic Response
Mining Operations Plan 2016 – 2022
The Springvale Colliery Mining Operations Plan for 2015 to 2022 was submitted to DRE and approved on the 25
th of February 2016.
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Topic Response
SMSR Report Feedback
Feedback from submitted November 2015 and March 2016 SMSR’s received from DRE requesting a response to seven identified points.
Points have been addressed either in this report or via covering letter to DRE.
East Wolgan Swamp Restoration
Rehabilitation works at East Wolgan Swamp commenced in January 2014 and the following activities are being undertaken:
detailed vegetation mapping (before rehabilitation);
swamp re-hydration works- construction and strategic placement of coir logs, sandbag and jute mesh weirs;
direct seeding - collecting seeds off targeted species already within the swamp and placing in rehabilitation area; and
brush matting - collecting branches from vegetation in the area adjacent and placing it in the rehabilitation area to encourage and provide cover for new growth.
There has been no updates obtained during the July SMSR reporting period.
Soil Moisture Monitoring Program
With the change in groundwater consultants difficulty was experienced with
instrument compatibility. The previous monitoring equipment being utilised was
quite old and not manufactured anymore. More modern equipment does not fit
down the small diameter PVC. Due to the location within swamps approval
requirements for the hole would need to be further considered.
As there have been no emergency discharges or mining in the vicinity of this trial
monitoring location changes would be attributable to climatic conditions.
The application of soil moisture monitoring or similar methodology in future monitoring programs in future extraction areas will be considered for suitability based on subsidence impact performance measures.
No changes to the EMP are proposed.
SMSR Format The format for the reporting was updated to align more clearly with the Subsidence Monitoring status report requirements and reflects the monitoring locations in the approved Environmental Monitoring Program. The alignment of the SMSR Report was considered to improve the integration of SMP approval, reporting and monitoring requirements.
As noted in Table 3 above, the EMP was approved by DRE during the reporting period. The included monitoring sites include both Subsidence Environment Monitoring Program SV-MS-036 and 418 EMP. The program(s) approved at the time of undermining defines monitoring sites and triggers.
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5. OBSERVED IMPACTS AND NOTIFICATIONS
There have been no observed subsidence impacts, incidents or service difficulties during the retreat
of Longwall 418. Inspections were conducted by Craven Elliston & Hayes before and after mining.
Details regarding the photo-monitoring undertaken are documented in Section 6.8
6. MONITORING PROGRAM This section presents the subsidence and environmental monitoring that was undertaken during the
reporting period. Subsidence monitoring locations (or subsidence lines) are presented in Figure 2.
The environmental monitoring locations are presented in Figure 3. Plans are presented in Appendix 1.
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Figure 3 Environmental Monitoring Locations
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6.1. Subsidence
All required subsidence monitoring lines have been installed and all pre-mining subsidence surveys
completed in accordance with the approved Subsidence Monitoring and Reporting Program. All
subsidence, tilt and strain results are within the predicted range.
The maximum recorded subsidence values for each of Springvale’s Subsidence Lines for LW418
during the reporting period were:
B Line – Surveyed 15/05/2016 – Value = -1.275m
Y Line – Surveyed 15/02/2016 – Value = -0.552m
CWS Line – Surveyed 10/8/2015 – Value = -0.018m
X Line – Surveyed 15/02/2016 – Value = -0.224m
V Line – Surveyed 03/02/2016 – Value = -0.511m
W Line – Surveyed 15/02/2016 – Value = -0.741m
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6.2. Rainfall
Rainfall data is summarised in Table 5 and Figure 4.
Rainfall data Table 5.
Month Observed Newnes
Plateau (mm) Long Term Average
Newnes Plateau (mm) Observed
Lithgow (mm) Long Term Average
Lithgow (mm)
February 2016 15.4 125.8 28.8 79.1
March 2016 52.2 98.4 69.6 65
April 2016 8.8 67.3 6.2 42.5
May 2016 29.4 44.6 26 49.4
Figure 4 Monthly Rainfall
From the rainfall data collected during the monitoring period (1
st February 2016 to 31
st May 2016), the
following general observations can be made:
Observed rainfall at Newnes Plateau for the reporting period is below average for all months. Ranging from 12% and 13% of the long term average in February and April, and 53% and 66% in March and May.
Total rainfall for the period was 105.8mm, which equates to 31.5% of the long term average for the same period.
Over the reporting period on the plateau there were two rain days in excess of 10mm per day, and four days of 5 to 10mm per day.
Cumulative rainfall deficit (CRD) considers the long term impacts of the effect of rainfall. This assists in the interpretation of data undertaken as part of the subsidence environmental monitoring program.
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6.3. Groundwater Monitoring Program
6.3.1. Methodology
Groundwater monitoring is carried out within the Newnes Plateau Shrub Swamps in order to monitor
the Standing Water Level of shallow aquifers. Deeper piezometers are installed on the plateau/ridges
(to monitor depth of aquifers) in between the Shrub Swamps. Groundwater monitoring locations are
listed in Tables 6 and 7 below.
EMP Monitoring Locations Table 6.
Monitoring
Site
Swamp Name Site in 2009
EMP?
2009 EMP
Reference
Site in 2015
EMP?
Quality
Monitoring
2015
WE1 East Wolgan
Swamp
Yes EW-SV6 No N/A
WE2 East Wolgan
Swamp
Yes EWS-SV7 No N/A
SS1 Sunnyside
Swamp
Yes SS-SV8 No N/A
SS2 Sunnyside
Swamp
Yes SS-SV9 No N/A
SS3 Sunnyside
Swamp
No N/A No N/A
SS4 Sunnyside
Swamp
No N/A No N/A
SS5 Sunnyside
Swamp
No N/A No N/A
CW1 Carne West
Swamp
Yes CW-SV10 Yes Yes
CW2 Carne West
Swamp
Yes CW-SV11 Yes Yes
CW3 Carne West
Swamp
No N/A Yes No
CW4 Carne West
Swamp
No N/A Yes No
SSE1 Sunnyside East
Swamp
Yes SSE-SV12 Yes No
SSE2 Sunnyside East
Swamp
Yes SSE-SV13 Yes No
SSE3 Sunnyside East Yes SSE-SV14 Yes Yes
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Monitoring
Site
Swamp Name Site in 2009
EMP?
2009 EMP
Reference
Site in 2015
EMP?
Quality
Monitoring
2015
Swamp
SW1 Sunnyside West
Heath
Yes SSW1 No N/A
CC1 Carne Central
Swamp
No N/A Yes Yes
MS1 Marrangaroo
Swamp
No N/A Yes Yes
TS1 Tri Star Swamp No N/A Yes No
TG1 Twin Gully
Swamp
No N/A Yes No
Ridge/Aquifer Piezometer Locations Table 7.
Monitoring Site Location Site in 2009
EMP?
2009 EMP
Reference
Site in 2015
EMP?
RSS Ridge Piezometer
over 411
Gateroads
Yes R-SV3 Yes
RSE Ridge Piezometer
over 415
Longwall Block
Yes R-SV4 No
SPR1101/SPR1401* Over Longwall
416
No N/A Yes
SPR1104/RCW Ridge Piezometer
over 419
gateroads
Yes R-SV5 Yes
SPR1107 Over Longwall
420
No N/A Yes
SPR1108 South of Longwall
420 over
Longwall 427
No N/A Yes
SPR1109 Overall Longwall
418
No N/A Yes
SPR1110 Over Longwall
416/417
No N/A Yes
SPR1111 North of Longwall No N/A Yes
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Monitoring Site Location Site in 2009
EMP?
2009 EMP
Reference
Site in 2015
EMP?
422
SPR1113 Over Longwall
423
No N/A Yes
AP5PR NW of Angus
Place Mine
No N/A Yes
*Note: SPR1101 water levels dropped below the base of the piezometer in December 2013 and SPR1401 was installed as a replacement in November 2014.
Monitoring and reporting has been undertaken in accordance with the Springvale Colliery Longwalls
411 to 418 Subsidence Management Plan Environmental Management Plan Approval dated 14th of
August 2015.
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6.3.2. Groundwater Level Results
Monitoring results completed up to May 2016 are summarised in the below section.
East Wolgan Swamp
Water levels at East Wolgan Swamp are monitored at WE1 and WE2 and displayed below in Figure
5.
Water levels at East Wolgan have previously responded to periods of above average rainfall. Since early 2009 the responses have declined to short duration spikes in water level. Both WE1 and WE2 have remained dry over the reporting period, while WE2 showed a minor response to rainfall during January.
Figure 5 East Wolgan Swamp Hydrograph
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Sunnyside Swamp
Water levels at Sunnyside Swamp are monitored by five piezometers, SS1, SS2, SS3, SS4 and SS5.
Sites SS1 and SS2 were part of the 2009 SMP EMP in relation to the mining of Longwalls 414 and
above Sunnyside Swamp. No sites were part of the 2014 SMP EMP as mining had passed the
swamp area, however monitoring of all five piezometers has continued. For the purposes of this
report, only SS1 and SS2 will be analysed as these are the only sites included for monitoring under
an SMP EMP.
Figure 6 below shows water levels at SS1 and SS2.
SS1 and SS2 show a declining water level over the review period as water levels within the swamp
equilibrate with the reduced rainfall recharge.
Figure 6 Sunnyside Swamp Hydrograph
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Carne West Swamp
Water levels at West Carne Swamp are monitored at piezometers CW1, CW2, CW3 and CW4 (Figure
7).
CW1 and CW2 have shown uncharacteristic declines since early 2014. Previous observations have demonstrated consistent water levels since piezometer installation in mid-2005. CW1 remained dry over the reporting period. CW2 showed an apparent but very minor response to elevated rainfall during January; however the response is so small it may be due to barometric compensation of the data. No other responses were observed during the reporting period.
CW3 and CW4 showed declining water levels during 2013 and have remained below the base of the piezometers since then. No responses were observed during the reporting period.
Figure 7 Carne West Hydrograph
While baseline data collected shows a higher water level, a correlation can be drawn with the
cumulative rainfall deficit observed on the Newnes Plateau in more recent monitoring rounds. The
decrease in groundwater level has been observed since May 2013.
CW1 and CW2 were within the angle of draw of Longwall 418 in December 2015 and reported to the
Department of Environment and DRE on the 22nd
of December 2015 following notification of the
trigger by RPS on the 18th of December 2015.
In the case of the CW1 and CW2 swamp piezometer triggers, the preliminary investigation indicates
that water levels at CW1 and CW2 piezometers now display trends that are more rainfall dependent
as opposed to predominantly groundwater dependent, which had been the case for the entire
baseline monitoring period from 2005 up to 2014. Further data analysis is required to determine if the
changes to water levels in Carne West Swamp are related to mine subsidence or the decline in the
regional groundwater table aquifer, which appears to be a delayed response to longer term climatic
influences.
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CW3 and CW4 were within the angle of draw of Longwall 417 in March and April 2015.
In the case of the CW3 and CW4 swamp piezometer triggers under the LW 415-417 THPSS MMP,
the preliminary investigation indicates that given the trigger level was reached prior to mining within
200m of the monitoring location, a rainfall deficit is likely to have contributed to the reduction in water
level at CW3 and CW4. The change in climatic conditions has resulted in a change in pre-mining
groundwater levels which is not reflected by the triggers defined in the THPSS MMP. This behaviour
is similarly exemplified in the Tri Star reference swamp.
There is no evidence of mining related impact to Carne Swamp.
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Sunnyside East Swamp
Water levels at Sunnyside East Swamp are monitored at piezometers SSE1, SSE2 and SSE3 (Figure
8).
Water levels at SSE1 have remained at or below the base of the piezometer since 2013. No response
was observed during the reporting period.
Water levels at SSE2 and SSE3 showed a decline during 2012/2013 that correlates with a downturn
in the CRD, however water levels declined to below previously recorded levels. Water levels in SSE2
have previously shown small fluctuations marginally above the base of the piezometer, however there
have been no responses to significant rainfall events as has been observed in the past. SSE2
remained below the base of the piezometer for the reporting period.
SSE3 displayed responses to above average rainfall in the previous reporting period; however they
were noted as being smaller than for similar rainfall events in the past. Having shown a minor
response to rainfall during January, SSE3 remained below the base of the piezometer for the
reporting period.
Figure 8 Sunnyside East Hydrograph
SSE1 was within the angle of draw of Longwall 416 in January 2013.
In the case of the SSE1 swamp piezometer trigger under the LW 415-417 THPSS MMP, the
preliminary investigation indicates that the likely cause was an extended period of dry weather, which
contributed to the reduction in water level within the reference swamp piezometers (which are located
away from mining activities).
Following the implementation of the action plan, reporting was conducted by RPS and Gingra
Ecological Surveys.
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RPS concluded that “water levels at TS1 and TG1 were both above the 95th percentile when the
trigger level was exceeded in SSE1. The statistics for MS1 and CC1 are heavily skewed by sampling
events which are displayed as sharp drawdown spikes in the hydrograph. These events are not
reflective of mining activities and recover to normal groundwater level relatively quickly. Both these
sites would have exceeded the 95th percentile if the sampling events were not taken into account.
The reference sites support the low water levels observed in SSE1.”
Gingra concluded that “The patterns of decline observed in vegetation along Sunnyside East Swamp
appear, at this stage, to be driven by the combination of the post-fire response of vegetation and
climatic conditions which have prevailed since early 2012.”
SSE2 and SSE3 were within the angle of draw of Longwall 417 between November 2014 and March
2015.
In the case of the SSE2 and SSE3 swamp piezometer triggers under the LW415-417 THPSS MMP, the preliminary investigation indicates a rainfall deficient may have contributed to the reduction in water level at the before mentioned monitoring locations. The change in climatic conditions has resulted in a change in pre-mining groundwater levels which is not reflected by the triggers defined in the THPSSMMP. At the location of the 3 piezometer sites, there has been no evidence of mining related impact.
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Sunnyside West Heath
Water level at West Sunnyside Swamp is monitored at piezometer SW1 (Figure 9). Over the
reporting period water levels are observed to remain within historical levels.
A clear relationship between rainfall and groundwater levels can be seen with SW1 groundwater
levels correlating with rainfall patterns and intensity. Following large rainfall events, if above average
rainfall conditions are not maintained the water levels quickly decline to the base of the piezometer.
This response is typical of SW1 and can be seen in previous observations.
Water levels were below the base of the piezometer for the majority of the reporting period following a
decline during February. Water levels at SW1 have previously been below base of casing and
typically coincide with sustained periods of below average rainfall.
Figure 9 Sunnyside West Hydrograph
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Reference Swamps
Water levels at reference swamps are presented in Figures 10 to 13.
Water levels in CC1 have typically remained above ground level. Over the review period water levels at CC1 show a rapid decline during February and March in response to decreased rainfall, then stabilise at around 0.25mbgl to 0.30mbgl. Water levels over the review period represent the lowest natural water levels observed at CC1.
Water levels in MS1 historically show fluctuations consistent with the CRD trend. Water levels over the reporting period show a rapid decline during February and March with an apparent stabilisation in the last half of the review period consistent with the decreasing trend in CRD. As with CC1, the reduced water levels at MS1 represent the lowest natural water levels on record.
Water levels at TS1 have historically shown significant variation, with a maximum range of the order of 4m. Water levels generally show a good correlation with CRD and have declined below base of piezometer on a number of occasions. Over the review period water levels have remained below the base of the piezometer. A minor apparent response is observed in February that may be attributable to the elevated rainfall in January; however the response is only minor and may be the result of barometric compensation.
Water levels at TG1 have historically remained within 0.25m of ground level, with only a few larger water level declines evident corresponding with the CRD trends. Over the review period, water levels declined during February and then stabilised at a new equilibrium level associated with the reduced rainfall recharge.
Figure 10 Carne Central Swamp Hydrograph
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Figure 11 Marrangaroo Swamp Hydrograph
Figure 12 Tri Star Swamp Hydrograph
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Figure 13 Twin Gully Swamp Hydrograph
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Ridge and Aquifer Piezometer Monitoring
The groundwater levels for ridge piezometers are shown in Figure 14 and 15.
During the reporting period, no ridge piezometers were within 200m of an active longwall. The
following is noted over the reporting period:
Impact Sites
Groundwater levels at groundwater monitoring impact sites are provided on Figure 14.
Water levels at SPR1101 dropped below the base of the piezometer in December 2013. A replacement bore, SPR1401, was installed in November 2014. Water levels at SPR1401 initially showed a decline due to subsidence equilibration from LW417 but stabilized over the latter half of 2015. A further, minor, stepped decline coinciding with LW418 is also apparent. Over the current reporting period water levels have remained stable.
The water level at SPR1104 was consistent over the reporting period showing the continuation of a slight declining trend.
Water levels at SPR1107 show the continuation of a gradual decline over the reporting period. As with SPR1104, a slight stepped decline is apparent during the previous reporting period, this is inferred to be associated with mining of LW418.
Water levels at SPR1109 showed the continuation of a gradual decline following the depressurisation event in late 2015 when the piezometer was undermined by LW418.
Over the reporting period water levels at SPR1110 have remained below the base of the piezometer.
The groundwater level at RSS has remained stable over the reporting period; a very gradual long term decline is evident.
Over the reporting period water levels at RSE have remained below the base of the piezometer.
Reference Sites
Groundwater levels at groundwater monitoring reference sites are provided on Figure 15.
Water levels at SPR1108, SPR1111, SPR1113, and AP5PR, generally show stable to slightly declining water levels over the reporting period. The decline follows a groundwater high over 2012 and 2013. Over the reporting period the declines range from 0.25m at SPR1108 to 0.66m at SPR1111.
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Figure 14 Impact Aquifer Piezometers
Figure 15 Reference Aquifer Piezometers
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SPR1101 SPR1101 was first within the angle of draw of Longwall 416 in September 2013. A trigger was activated in an aquifer piezometer (SPR1101) installed on the topographic ridge to the west of Sunnyside-East Swamp under the 415-417 THPSS MMP. The trigger was based on historical monitoring data which indicated a decline in the water level in SPR1101 piezometer. In the case of the SPR1101 aquifer piezometer trigger, the investigation indicated that the likely cause was the depth of drilling of the SPR1101 exploration borehole, which was subsequently inappropriately used as a water level monitoring bore. The drilling of the SPR1101 borehole, was likely to have intersected the zone of discontinuous fracturing (B-Zone) caused by subsidence related to the extraction of Longwall 416 at Springvale. Historical monitoring indicates that the aquifers which supply groundwater to the swamp have not been impacted by adjacent mining activities. The SPR1101 borehole was drilled to a depth below the aquifers which supply groundwater to the swamp, and it is considered that the decline in water level based on data from this borehole does not represent an impact to the groundwater system which supplies water to the swamp. SPR1109
LW418 was first within the angle of draw of SPR1109 in November 2015 and was reported to the
Department of Environment and DRE on the 22nd
of December 2015 following notification of the
trigger by RPS on the 18th of December 2015.
In the case of the SPR1109 aquifer piezometer trigger under the LW 415-417 and 418 THPSS MMP , it is considered likely that the changes to aquifer groundwater levels at SPR1109 are consistent with a delayed response to longer term climatic influences.
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6.3.3. Groundwater Quality Results
The 2015 EMP requires swamp groundwater quality monitoring at impact sites SSE3, CW1, and
CW2, and at reference sites CC1 and MS1. The swamps are monitored for parameters that act as
potential indicators of mining related impacts, these being pH, electrical conductivity, and iron.
Due to the prevailing dry conditions, the swamp water levels have remained beneath the base of the piezometer within CW1, CW2 and SSE3 during the reporting period.
pH readings from impact sites CW1, CW2, and SSE3; and reference sites MW1 and CC1 are
presented in Figure 16. Only measurements from CC1 and MS1 are available for the reporting period
due to the prevailing dry conditions. The pH levels for MS1 and CC1 remained within historic levels
and display a declining trend over the reporting period.
EC readings from impact sites CW1, CW2, and SSE3; and reference sites MW1 and CC1 are
presented in Figure 17. Only measurements from CC1 and MS1 are available for the reporting period
due to the prevailing dry conditions. The EC levels at MS1 remained within historic levels during the
reporting period, whilst the most recent measurement at CC1 is the lowest since monitoring
commenced in 2012. Over the review period CC1 displays a steep decline in EC while values at MS1
continued an increasing trend since mid-2015 followed by a sharp decline in EC during the last
monitoring round.
Iron readings from impact sites CW1, CW2 and SSE3, and reference sites MW1 and CC1 are
presented in Figure 18. No lab samples could be obtained from impact sites during the reporting
period due to the prevailing dry conditions. The iron levels within MS1 and CC1 show significant
fluctuations during the reporting period. CC1 shows a consistent and sharp declining trend, while
MS1 continued an increasing trend followed by a rapidly decline with the last monitoring round. The
trends are noted as being very similar to those displayed by the electrical conductivity at both
locations.
Figure 16 pH Swamp Piezometers
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Figure 17 EC Swamp Piezometers
Figure 18 Fe Swamp Piezometers
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6.4. Surface Water Monitoring Program
6.4.1. Methodology
Flow monitoring sites and standing water levels (where appropriate) within surface streams above
Springvale are located in the table below.
Surface Water Monitoring Sites Table 8.
Monitoring Site Description Site in 2009
EMP?
2009 EMP
Reference
Site in 2015
EMP?
East Wolgan
Upstream
Upstream Yes East Wolgan 1 No
East Wolgan
Downstream
Downstream Yes East Wolgan 2 No
Sunnyside U/S
Junction
Upstream Yes Wolgan Tributary
1
No
East Wolgan D/S
Junction
Downstream Yes Wolgan Tributary
2
No
Sunnyside U/S Upstream Yes Sunnyside 1 No
Sunnyside D/S Downstream Yes Sunnyside 2 No
Carne West
Upstream
Upstream Yes Carne West 1 No
Carne West
Downstream/
Carne West
Downstream Yes Carne West 2 Yes
CWP Nth end of Carne
West Swamp
No N/A Yes
SS3 D/S
Nth end of
Sunnyside East
Swamp
No N/A Yes
Marrangaroo
Creek Upstream
Marrangaroo
Creek Upstream
No N/A Yes
Streams flows are monitored on a fortnightly basis using a pygmy flow meter under the 2009 EMP
and monthly under 2015 EMP for flow, electrical conductivity, manganese, iron, temperature and
visual inspection of colour. Total suspended solids are monitored monthly. If there is no flow no
quality parameters are monitored. The exception is Carne West Pool where water pool monitoring is
undertaken to assist in monitoring stream flow.
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6.4.2. Surface water flows
Wolgan River
Surface flow contributions to the upper Wolgan River are monitored at tributaries at East Wolgan
River downstream of the junction with Sunnyside Swamp and at Sunnyside Swamp upstream of the
junction. Flows are shown on Figure 19. A small peak in flow occurred at the start of the review period
resulting from elevated rainfall, both sites then displayed declining low flow conditions over the review
period.
Figure 19 Wolgan River Flow
Table 9 shows a comparison of reporting period flow data with historical flow data for Wolgan River.
For both East Wolgan D/S Junction and Sunnyside U/S Junction, average flow for the reporting period
was below the long term average for all data. This is due to low rainfall conditions over the reporting
period.
Wolgan River Flow Statistics Table 9.
Monitoring Site
Average Stream Flow - All Data to 30/09/15 (KL/Day)
Average Reporting Period Stream Flow (KL/Day)
Stream Flow Range All data to 30/09/15 (KL/day)
Comments
East Wolgan D/S Junction
729 98 0 – 12,668
Low reporting period average due to below average rainfall conditions.
Sunnyside U/S Junction
698 126 0 – 8,977 Low reporting period average due to below average rainfall conditions.
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East Wolgan
East Wolgan Swamp is located in proximity to Longwall 411. There has been no mining in the vicinity
of this site. No emergency discharges have occurred during the reporting period.
Surface flows at East Wolgan swamp are monitored at East Wolgan Upstream and East Wolgan
Downstream. Historically, no significant flows are recorded at these locations and the sites were
recorded as being dry during the review period.
Historic flows are presented in Figure 20.
Sunnyside East Swamp
Surface flows at Sunnyside East swamp are monitored at SS3 Downstream. SS3 Downstream has been reported as dry since early 2015 and prior to this had only minor flows that were too low for gauging. SS3 Downstream remained dry during the reporting period.
Historic flows are presented in Figure 20.
Figure 20 East Wolgan and Sunnyside East Flow
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Sunnyside Swamp
Surface flows at Sunnyside Swamp are monitored at Sunnyside Upstream and Sunnyside
Downstream. Flows are shown on Figure 21. Over the reporting period low flows were recorded at
Sunnyside Upstream and Sunnyside Downstream. A decline from a rainfall induced small peak at the
start of the review period is evident.
Figure 21 Sunnyside Swamp Flow
Table 10 shows a comparison of reporting period flow data with historical flow data for Sunnyside
Swamp. Average flow during the reporting period for both Sunnyside U/S and D/S were below the
average values for all data. Average long-term flows at Sunnyside D/S are over 50% greater than
those at Sunnyside U/S.
Sunnyside Swamp Flow Statistics Table 10.
Monitoring site
Average Stream Flow - All Data to 30/09/15 (KL/Day)
Average Reporting Period Stream Flow (KL/Day)
Stream Flow Range All data to 30/09/15 (KL/day)
Comments
Sunnyside Swamp U/S
295 88 0 – 5,399 Low reporting period average due to below average rainfall conditions.
Sunnyside Swamp D/S
447 101 0 – 4,252 Low reporting period average due to below average rainfall conditions.
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Carne West Swamp
Surface water at Carne West Swamp is monitored at Carne West Upstream and Carne West Downstream as well as pool depth monitoring at Carne West Pool (CWP) adjacent to Carne West Downstream. Surface flows are typically too low for accurate gauging at Carne West Upstream and Downstream. Pool depths at CWP are shown on Figure 22.
CWP displays highly variable water depth. Peak depths appear to be declining consistent with the CRD. Over the reporting period CWP showed relatively shallow water depth but remained consistently wet.
Figure 22 CWP Waterhole
Flow results recorded at Carne West for the reporting period are displayed in Table 11 below.
Carne West Flow Results Table 11.
Date 21-March-16 4-April-16 20-April-16 4-May-16 18-May-16 31-May-16
Flow (kl/day) Dry Dry Dry Dry Dry Dry
Reference Site – Marrangaroo Creek
Dry or low flow measurements are usually recorded in Marrangaroo Creek. Flows over the reporting period are summarised on Table 12. Consistent flows are reported from February to May, ranging from 116 kL/day down to 21 kL/day. In mid to late May flows were too low to be measured.
Marrangaroo Creek Flow Gauging Table 12.
Date 8-Feb-16 23-Feb-16 9-Mar-16 22-Mar-16 5-Apr-16 21-Apr-16 2-May-16 17-May-16 30-May-16
Flow (kl/day) 116 94 39 36 33 21 39 too low too low
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6.4.3. Surface Water Quality
All surface water monitoring sites are monitored for electrical conductivity (EC), pH, manganese, iron, total suspended solids (TSS) and temperature. The monitoring results are discussed below. The results for temperature and TSS are discussed briefly below as they are both driven by climatic influences and can vary greatly depending on the time of day the samples are taken. Temperature fluctuations are dominated by the season and time of day the samples are obtained. TSS measurements are driven by rainfall runoff intensity and fluctuations will vary greatly depending on the time the sample is taken. Spot samples are generally not representative of true maximum and minimum values
As outlined above in section 6.4.2 Carne West and East Wolgan monitoring sites are not presented in this section as the monitoring sites were either dry or experienced low flow during the reporting period. The monitoring results at Carne West and East Wolgan are therefore unrepresentative of long term trends.
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Marrangaroo Creek Low flow measurements were recorded throughout the reporting period at Marangaroo Creek. When the flow is not high enough to record a flow reading the sample is considered unrepresentative as the water sample is likely to be stagnant.
Table 13 summarizes water quality data for the reporting period.
Marrangaroo Creek Quality Statistics Table 13.
Parameter Statistic 2006 – Current Reporting Period 95th
Percentile*
pH
Range 3.47 – 8.85 5.3 – 8.23
4.66 – 7.11 Median 5.6 6.4
Mean 5.6 6.6
EC (µS/cm)
Range 7 - 71 7 - 44
59 Median 30.0 23.0
Mean 32.6 23.22
Mn (mg/L)
Range 0 – 0.4 0.003 – 0.05
0.02 Median 0.010 0.009
Mean 0.015 0.008
Fe (mg/L)
Range 0 – 4.34 0.05 – 0.48
0.46 Median 0.05 0.08
Mean 0.17 0.16
Over the review pH values were recorded in the range 5.3 to 8.23, EC values ranged from 7µS/cm to 44µS/cm and manganese concentrations ranged from 0.003mg/L to 0.05mg/L. Iron concentrations ranged from 0.05mg/L to 0.48 mg/L, however during the last four monitoring events, iron concentrations have been below the limit of reporting.
Over the review period, all parameters at Marangaroo Creek remained within historical limits, and all mean and median values for the reporting period remained with the 95 percentile values.
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Wolgan River
Table 14 summarizes water quality data for the reporting period.
Wolgan River Quality Statistics Table 14.
Parameter
Statistic
Wolgan East D/S Junction
Sunnyside U/S Junction
2006 – Current
Reporting Period
95th
Percentile*
2006 – Current
Reporting Period
95th
Percentile*
pH
Range 3.66 – 8.30
5.94 – 8.02
6.15 – 7.70
3.87 – 8.49 5.75 – 7.95
6.22 – 7.80 Median 6.90 6.76 6.90 6.69
Mean 6.90 6.85 6.90 6.95
EC (µS/cm)
Range 4 – 350 22 – 44
75.0
5 – 390 18 – 42
65.0 Median 33.5 30.0 34.0 31.0
Mean 40.6 29.4 39.2 31.2
Mn (mg/L)
Range 0 – 0.472
0.003 – 0.009
0.012
0 – 0.30 0.003 – 0.005
0.010 Median 0.005 0.005 0.005 0.004
Mean 0.010 0.005 0.006 0.005
Fe (mg/L)
Range 0.05 – 3.13 0.21 – 0.90
1.28
0.11 – 1.76
0.23 – 1.00
1.31 Median 0.56 0.34 0.56 0.33
Mean 0.65 0.40 0.65 0.41
Both sites show highly variable pH throughout the reporting period with values remaining within
historical limits. The lower bounding values appear to show the continuation of a declining trend,
however, this is offset by the increased variability of the data. EC values are well within historical
limits and show only small fluctuations.
Long term manganese concentrations show a seasonal variation and this trend continued over the
reporting period. Average concentrations for the reporting period remained below the long term
average for both Wolgan River D/S Junction and Sunnyside U/S Junction.
Iron concentrations showed a declining trend over the reporting period and were well below the long
term average for both Wolgan River D/S Junction and Sunnyside U/S Junction.
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Sunnyside Swamp
Table 15 summarizes water quality data for the reporting period.
Sunnyside Swamp Quality Statistics Table 15.
Parameter
Statistic
Sunnyside Swamp U/S
Sunnyside Swamp D/S
2006 – Current
Reporting Period
95th
Percentile*
2006 – Current
Reporting Period
95th
Percentile*
pH
Range 5.31 – 8.94 5.66 – 6.30
5.82 – 7.24
5.55 – 8.4 6.37– 7.83
6.20 – 7.71 Median 6.70 5.88 6.85 6.75
Mean 6.64 5.93 6.84 6.81
EC (µS/cm)
Range 1 – 820 32 - 53
75.0
1 – 840 31 – 38
200 Median 47.0 36.5 43.0 35.0
Mean 56.0 37.6 49.4 34.4
Mn (mg/L)
Range 0.002 – 0.071
0.012 – 0.026
0.017
0 – 2.5 0.003 – 0.009
0.016 Median 0.007 0.015 0.005 0.005
Mean 0.008 0.017 0.007 0.005
Fe (mg/L)
Range 0.11 – 2.15 0.16 – 1.14
1.50
0 – 5 0. 4 – 1.34
2.02 Median 0.57 0.30 0.74 0.49
Mean 0.68 0.40 0.84 0.62
pH levels have fluctuated but maintain relatively stable trends at both Sunnyside U/S and Sunnyside
D/S, with Sunnyside D/S elevated above Sunnyside U/S. pH values have declined from a peak in
mid-2015 and all values for the reporting period are within historical limits.
EC remained relatedly stable and within historic limits. Median and mean concentrations for the
reporting period are below historical levels at both Sunnyside U/S and Sunnyside D/S (Figure 25).
The peak manganese concentration at Sunnyside Swamp U/S exceeded the 95th percentile; however
the mean and median values were below or equal the 95th percentile (Table 5.7 and Figure 26).
Manganese concentrations at both sites show a consistent declining trend over the previous reporting
period. Concentrations at both sites remained within historical limits.
Filtered Iron remained within historic limits at both sites, although values spiked to 1.14mg/L and 1.34
mg/L at the U/S and D/S sites respectively at the start of the review period. Following the spike,
concentrations returned to previous levels and then showed a declining trend over the remainder of
the reporting period.
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6.5. Fauna Monitoring Program
6.5.1. Methodology
As part of the on-going monitoring program at Springvale, fauna monitoring is undertaken three times
per year, during spring, summer and autumn. Monitoring was undertaken at five locations during the
reporting period, as outlined in Table 16. Autumn monitoring was conducted between the 15th and 19
th
of February and 4th and 8
th of April 2016.
Fauna Monitoring Sites Table 16.
Location Site
Newnes Plateau Woodland F-SV2
Sunnyside Swamp F-SV3
Carne West Swamp F-SV4
Carne West Swamp South F-SV5
East Wolgan Swamp F-AP3
The faunal surveys sample a range of faunal groups with a specific emphasis on threatened and
endangered species. Targeted searches are carried out for threatened species during the season
within which they are most active.
Data from the surveys is then analysed to show:
Species count;
Habitat characteristics;
Species diversity; and
Species richness.
6.5.2. Results
Habitat Measurements
Habitat characteristics are presented below in Table 17. A non-parametric Kruskal-Wallis test shows
no significant differences between each of the sites sampled in autumn 2016. There are also no
significant differences between the habitat characteristics measured between 2004 and 2016
(Kruskal-Wallis One Way Analysis of Variance on Ranks). Most of the cover parameters at the survey
sites have risen since the commencement of monitoring.
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Autumn 2016 Habitat Characteristics Table 17.
% Cover SV2 SV3 SV4 SV5 AP3 Mean
Tree Cover 48 12 20 8 12 20
Tall Shrub Cover 12 44 36 28 32 30
Tall Sapling Cover 14 8 8 8 0 8
Low Shrub Cover 92 72 68 72 84 78
Low Sapling
Cover
36 20 8 4 8 15
Fern Cover 28 56 20 48 24 35
Cutting Grass 52 36 16 8 16 26
Grass Cover 84 44 44 16 20 42
Forb Cover 4 68 76 80 92 64
Reed Cover 0 64 36 68 76 49
Vine Cover 0 0 4 0 0 1
Litter Cover 100 100 100 100 100 100
Log Cover 48 12 44 12 12 26
Rock Cover 24 4 4 0 0 6
Tree Hollows 0 0 8 4 0 2
Habitat complexity scores are used to provide an index of habitat complexity that can be used to
determine changes in habitats over time. The system scores the following parameters: tree cover, tall
and short shrub cover, ground cover, logs/rocks and litter cover. The scores range from 0 to 3, hence
the maximum score is 18. Scores for each site during the monitoring period are provided in Table 18
and a comparison of autumn scores from 2011 – 2016 are provided in Table 19.
The scores indicate moderate to high habitat complexity. There are no significant differences between
the complexity scores for each site, or between the annual surveys.
Habitat Complexity Scores for Monitoring Sites Table 18.
AP3 SV2 SV3 SV4 SV5 Mean
Habitat Complexity Scores Autumn 2016 13 16 14 14 12 14
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Mean Habitat Complexity Scores 2011 -2016 Table 19.
Mean of Sites
Total Habitat Complexity Scores Autumn 2016 14
Total Habitat Complexity Scores Autumn 2015 13
Total Habitat Complexity Scores Autumn 2014 15
Total Habitat Complexity Scores Autumn 2013 15
Total Habitat Complexity Scores Autumn 2012 15
Total Habitat Complexity Scores Autumn 2011 15
Biodiversity
Twenty native mammals (plus three introduced), forty-eight birds, six reptiles and two amphibian
species were recorded during the autumn monitoring survey within the SMP Area. Biodiversity indices
are provided in Table 20. There are no significant differences from previous year’s results for native
mammals and birds.
Biodiversity Indices for fauna in Springvale SMP Area Table 20.
Evenness
Simpson’s
Index of
Diversity
Total
Numbers
Recorded
Species
Richness
Fauna
Group
0.867 0.945 481 48 Birds
0.861 0.861 102 11 Mammals
(non-bat)
0.796 0.721 24 6 Reptiles
- - 3 2 Amphibians
Eight threatened species were located during the surveys (Gang-gang Cockatoo, Flame Robin,
Scarlet Robin, Varied Sittella, Little Pied Bat, Eastern False Pipistrelle, Eastern Bentwing-Bat, Yellow-
bellied Sheathtail Bat and Blue Mountains Water Skink), as well as a number of bird species
considered to be declining in the western slopes of NSW. The water skink was captured in West
Carne Swamp and is considered a long-time resident in that area.
Analysis of data shows no significant effects from the Springvale mining operations.
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6.6. Flora Monitoring Program
Flora Monitoring sites in the 2009 EMP and 2015 EMP are listed in Table 21.
Flora Monitoring Sites Table 21.
Monitoring Site Description Site in 2009 EMP? Site in 2015 EMP?
NP07 Sunnyside West Heath Yes No
KC01 Kangaroo Creek Swamp Yes No
KC02 Kangaroo Creek Swamp Yes No
NO005 Junction Swamp Yes No
NP006 Junction Swamp Yes No
WE01 Sunnyside Swamp Yes No
WE02 Sunnyside Swamp Yes No
CLA03 Prickly Swamp Yes No
CLA04 Prickly Swamp Yes No
WC01 Carne West Swamp Yes Yes
WC02 Carne West Swamp Yes Yes
WC03 Carne West Swamp Yes Yes
WC04 Carne West Swamp Yes Yes
SSE01 Sunnyside East No Yes
TG01 Twin Gully No Yes
TG02 Twin Gully No Yes
TRI01 Tristar No Yes
TRI02 Tristar No Yes
LGG01 Lower Gang Gang Swamp No Yes
UGE01 Upper Gang Gang East Swamp No Yes
BS01 Barrier Swamp No Yes
CCS01 Carne Central Swamp No Yes
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The following parameters are measured at each quadrate during the monitoring period:
Species Composition Cover/abundance;
Condition of Swamps and associated vegetation;
Plant species diversity;
Discussion on comparative monitoring results; and
Indicator species including eucalypts, sphagnum cristatum.
Monitoring is carried out in summer, autumn and spring.
The following sections summarises results from the interim summer 2016 monitoring results report.
6.7. Native Species Diversity
A modified Braun-Blanquet scale was used to visually estimate cover abundance for species
occurring within each site.
6.7.1. THPSS MMP
Total native plant species richness for impact and reference sites is shown in Table 22. Results from
the quadrat (400 m2) and four 20 m transects are tabulated for comparison between sampling
methods and reference/impact sites.
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Total native plant species richness Table 22.
Site Species Richness Shannon-Wiener Index
(point intercept method) Evenness
400m2 Quadrat Point Intercept Method
Impact sites
WC01 11 11 2.01 0.84
WC02 13 13 1.96 0.76
WC03 14 14 2.05 0.78
WC04 13 12 2.07 0.83
SSE01 17 17 2.25 0.79
Mean±SD 13.6 ± 2.2
13.6 ± 2.2 2.07 ± 0.11 0.80 ± 0.03
Reference sites
TG01 18 14 2.19 0.83
TG02 20 19 2.32 0.79
TRI01 23 17 2.16 0.76
TRI02 18 17 2.06 0.74
LGG01 20 20 2.41 0.80
UGE01 19 19 2.22 0.75
BS01 16 13 2.10 0.82
CCS01 18 18 2.17 0.75
Mean±SD 19.0 ± 2.1
18.0 ± 1.6 2.20 ± 0.78 0.78 ± 0.03
Lower mean native species richness was observed in impact sites (13.6 ± 2.2) when compared with
reference sites (19.0 ± 2.1). A similar observation was calculated from the point intercept method
(impact = 13.6 ± 2.2; reference = 18.0 ± 1.6).
A lower Shannon-Wiener Index score was calculated for impact sites (2.07 ± 0.11) compared with
reference sites (2.20 ± 0.78) for the point intercept method.
Analysis using the native plant species richness trigger levels indicated an ‘exceedance’ in three
impact sites and four reference sites for the spring monitoring period. For impact sites a trigger
exceedance has recurred at WC02 and triggers have been detected for the first time at WC01 and
SSE01. There were also exceedances at four reference sites (TRI01, LGG01, UGE01 and BS01).
Exceedances are in bold in Table 21 and listed below against relevant trigger levels.
WC01 (Impact Site) – 11 versus a 11.2 trigger level;
WC02 (Impact Site) – 13 versus a 13.3 trigger level;
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SSE01 (Impact Site) – 17 versus a 20.3 trigger level;
TRI01 (Reference Site) – 23 versus a 25.3 trigger level;
LGG01 (Reference Site) – 20 versus a 20.3 trigger level;
UGE01 (Reference Site) – 19 versus a 20.3 trigger level; and
BS01 (Reference Site) – 16 versus a 18.2 trigger level.
Figure 23 depicts the total native plant species richness results per site.
Figure 23 Native plant species richness at each site. Solid bars represent Summer 2016
results below baseline values. Lines above and below boxes represent ± 30%
trigger values. When the box obscures the line an exceedance has occurred.
Reference sites were inexplicably found to fail the flora trigger levels more so than impact sites. The
precise reasons for this are unknown although Erskine and Fletcher (2011) indicate a number of
potential causal environmental factors other than mining (e.g. climate, biotic, or anthropogenic)
requiring consideration. It should be noted that the preceding months have been uncharacteristically
warmer and drier than historical weather data would otherwise indicate. This could explain the overall
trend of declining species richness across all sites (THPSS – Annual Monitoring 2015, RPS 2016).
6.7.2. 2009 EMP
Total native plant species richness for impact and reference sites in the 2009 SMP EMP is shown in
Figure 24. Data for four years (2013 to 2016) is presented graphically to compare spring to early
summer monitoring results.
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Figure 24 Native species richness recorded in SEMP monitoring sites for 2013, 2014, 2015
and 2016
Monitoring sites NP005, NP006, NP007, SS01, SS02 and WC02 show a decline in total native plant
species richness since 2013 (Figure 24). However, the significance of this observed decline is difficult
to interpret for the following reasons:
Repeated measures were not possible for these sites due to inaccuracies in the pre 2015 reporting of site coordinates. The projection of these coordinates resulted in sites being located on non-swamp vegetation with no nearby swamp vegetation being observed. The 2016 dataset was obtained from sites established in nearby swamp vegetation, which are unlikely to represent conditions observed in pre 2015 monitoring.
NP007 has been burnt. The influence of post fire recovery on species richness data at this site cannot be separated from the impacts of mining.
Uncharacteristically dry conditions have been experienced across the whole monitoring area, for 2 consecutive years and are likely contributing to the reductions in species richness across the reference and impact sites.
‘Total native species’ includes both swamp and non-swamp species.
Results may be influenced by larger climate change related factors which are not measurable over such a short time frame. No analyses of the effects of climate change have been performed for this project.
6.8. Eucalypt Recruitment
Non-swamp eucalypt presence was estimated by summing incidence recorded in each 0.5 m x 0.5 m
quadrat centred on sequential 1 metre intervals along each of the four parallel transects. This
provided a total of approximately 80 quantitative measurements of eucalypt presence per monitoring
quadrat.
6.8.1. THPSS MMP Sites
Eucalypt recruitment within monitoring sites for the summer survey period is shown in Table 23 below.
Eucalypt recruitment in Summer 2016 Table 23.
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Site Transect (metre intercept)
2 9 11 17
Impact
WC01 - - - -
WC02 - - - -
WC03 - - - -
WC04 - - - -
SSE01 - 3 - 2
Reference
TG01 - - - -
TG02 - - - -
TRI01 - - - -
TRI02 - - - -
LGG01 - - - -
UGE01 - - - -
BS01 - - - -
CCS01 - - - 6
No increase in the incidence of eucalypt recruits was observed in any impact sites; however there
was a great increase at reference site CCS01. The reference swamp in question is typically drier than
other shrub swamps and the occurrence is unlikely to represent a substantial change in conditions.
Summer monitoring results identified no change from spring 2015 monitoring in Eucalyptus
recruitment in impact site SSE01 and reference sites TG01 and TG02. None of the sites exceeded
the trigger value for Eucalypt recruitment (i.e. more than 3 individual plants within a year). Detection of
Eucalypt recruitment in summer has not shown advancement or indication of further recruitment from
the previous winter and spring monitoring events where Eucalypt recruitment was noted in two impact
sites (WC02 and WC04) and three reference sites (TG01, TG02 and TRI02).
6.8.2. 2009 EMP
No increase in eucalypt recruitment was observed in the SEMP monitoring sites during the 2016
summer survey period.
6.9. Species Condition Scores
Four parallel transects were established to measure species condition scores. The starting points of
these transects were positioned randomly along a predetermined edge of the 400 m2 permanent
monitoring quadrat. A condition score was estimated for each plant species intersected every 0.5 m
along the transects.
6.9.1. THPSS MMP Sites
Overall mean species condition scores for impact and reference sites are shown in Table 24.Mean
condition scores for Gleichenia dicarpa have also been included as this is a key swamp species.
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Overall condition scores for each site and for key swamp species Gleichenia Table 24.dicarpa
Site Overall mean condition Gleichenia dicarpa mean condition
Impact
WC01 3.8 2.7
WC02 3.6 2.9
WC03 4.1 2.9
WC04 4.1 3.3
SSE01 3.8 3.5
Mean condition (impact) 3.9 3.1
Reference
TG01 3.4 3.9
TG02 3.4 3.4
TRI01 4.2 3.7
TRI02 4.1 3.4
LGG01 3.8 3.8
UGE01 4.0 4.0
BS01 3.5 3.4
CCS01 4.0 4.0
Mean condition (reference) 3.8 3.7
The mean condition score for overall key species in impact sites was 3.9 compared with 3.8 for
reference sites. The mean condition score for Gleichenia dicarpa impact sites was 3.1 compared with
3.7 for reference sites. None of the impact sites (overall or Gleichenia dicarpa) had a mean condition
score of 2.5 or less, therefore none of the impact sites have triggered the performance criteria.
6.9.2. 2009 EMP
Mean species condition scores for SMP Sites are shown in Table 25.
SMP Mean Species Condition Table 25.
Site 2013 2014 2015 2016 Change
NP007 2.34 2.14 4.11 3.92 No change
KC01 2.56 2.63 4.43 4.31 No change
KC02 2.25 2.76 4.13 4.21 No change
NP005 2.16 2.32 3.96 4.59 No change
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Site 2013 2014 2015 2016 Change
NP006 2.33 1.77 4.06 4.00 No change
SS01 2.45 2.36 3.94 4.00 No change
SS02 2.75 2.80 4.15 4.20 No change
WC01 3.50 3.08 3.75 4.00 No change
WC02 2.74 2.73 4.27 4.00 No change
WC03 2.80 3.55 4.18 4.00 No change
WC04 2.59 2.77 4.41 4.26 No change
CLA03 1.67 2.13 1.98 4.70 Improved condition
CLA04 2.24 2.42 2.48 4.15 Improved condition
The improved condition detected in spring 2015 has continued and it is still unclear as to whether it is
a consequence of observer bias and/or improved condition following extreme weather events (i.e.
2013 fires and snow storm in 2014). Further monitoring will be utilised to evaluate whether observer
bias is a factor to consider in the evaluation of this data.
6.10. Non Live Ground Cover
Bare earth scoring was estimated at each of the 0.5 m intervals inspected for species condition.
6.10.1. THPSS MMP Sites
Percent of non-live ground cover was estimated using both the Braun-Blanquet cover abundance
scale for the entire 400 m2 quadrat and the point intercept method. Results are tabulated in Table 26.
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Non-live ground cover (cover abundance and point intercept methods) Table 26.
Site Bare ground (modified Braun Blanquet
cover abundance score) Point intercept Method (%)
Impact
WC01 1 1.3
WC02 1 0
WC03 1 8.8
WC04 1 1.3
SSE01 1 1.3
Reference
TG01 1 1.8
TG02 1 1.8
TRI01 1 0
TRI02 1 0.6
LGG01 1 0.6
UGE01 1 2.5
BS01 1 0
CCS01 1 2.5
Neither method identified a substantial area of bare earth within the impact sites with both methods
obtaining similar results.
Data comparisons with trigger values show no increase of bare ground of more than 100 m2. No
trigger of this parameter was observed in the summer 2016 monitoring period.
6.10.2. 2009 EMP
No detectable change in non-live groundcover was observed in the SEMP monitoring sites since
2013.
6.11. Establishment of Non-native Weeds
Non-native weed presence was estimated by summing incidence recorded in each 0.5 m x 0.5 m
quadrat centred on sequential 1 m intervals along each of the four parallel transects. Species name
was recorded. This provided a total of approximately 80 quantitative measurements of weed presence
per monitoring quadrat.
The main weed species previously observed in the monitoring sites are Catsear (Hypochaeris
radicata*) and Yorkshire Fog (Holcus lanatus*).
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6.11.1. THPSS MMP Sites
No weeds were detected using the point intercept method, or identified within 400 m2 flora quadrats,
although it is likely weeds exist within some of the quadrats as previously detected, it is unlikely there
has been an increase, and no exceedance triggers have occurred for summer 2016.
6.11.2. 2009 EMP
Only one instance of weeds was detected at the KC01 site. Although it is likely weeds exist within
some of the quadrate as previously detected, it is unlikely there has been a substantial increase.
6.12. Conclusions
Monitoring results were compared with the flora trigger levels specified in the THPSS MMP. The
results of this comparison are provided in Table 27.
Monitoring results and flora trigger levels Table 27.
Performance indicator
Parameter measured Trigger level Summer 2016
Change in species assemblage
Change in diversity of native species
A change in the number of species of greater than 30 % for a given site within a three year period.
Trigger in three impact sites (WC01, WC02 and SSE01) and four reference sites (TRI01, UGE01, LGG01 and BS01).
Recruitment of eucalypt species
An increase in eucalypts in an impact site compared to reference sites of more than three individual plants within a one year period.
No impact sites showed an increase in eucalypt recruitment beyond the trigger level. Eucalypt recruitment has stabilised in SSE01 after approaching the trigger threshold.
Change in condition
Condition of key species
A decline in condition score at an impact site of more than 1.5 compared to the average condition score at reference sites within a one year period.
No impact sites showed a decrease in condition beyond the trigger level.
Non-live ground cover An increase of bare ground of more than 100m
2 in a site
within a three year period.
No impact sites showed an increase in bare earth beyond the trigger level.
Non-native weeds
An increase in non-native weed species of more than 4 in a monitoring site (each having a cover of greater than 5%) compared to the average number in reference sites within a one year period.
No impact sites showed an increase in weed species beyond the trigger level. Invasive species previously detected in CCS01 and LGG01.
Trigger exceedances were recorded at impact sites WC01, WC02 and SSE01 as a result of the
survey monitoring. In the case of WC01 and WC02 the trigger appears to be a result of missed or
undifferentiated fringe dry sclerophyll species and not a decline in the richness of typical swamp
species. The decline in species richness at SSE01 also requires further monitoring. The declining
conditions of Gleichenia dicarpa, a key swamp species in the Carne West swamp, should be closely
monitored as it may trigger further investigations in subsequent surveys.
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6.13. Photo-monitoring
6.13.1. Surface Features
Photographic inspections are conducted pre and post mining. The surveys target surface features
which may include rock formations, drainage lines, roads, Forests NSW tracks, waterholes, steep
slopes and rock beds within the watercourses.
Table 28 summarises the photographic survey monitoring undertaken as relevant to Longwall 418
extraction.
Longwall 418 Photographic Monitoring Summary Table 28.
Area Photographed Date Photographed Resurvey Number
LW418 Areas 1,2,
(Pre-mining)
2/2/2014 and 4/4/2014 Baseline Survey
LW418 Areas 1,2,
(Pre-mining)
20/8/2014 and 29/8/2014 Resurvey 2*
LW 418 Areas 1, 2
(Pre-mining)
25/2/2015 and 26/2/2015 Resurvey 3
LW418 Areas 1, 2, 6/8/2015 Resurvey 4
LW418 Undermining 23/10/2015 Resurvey 5
LW418 Undermining 1 11/11/2015 Resurvey 6
LW418 Area 1 Undermining 21/12/2015 Resurvey 7
LW418 Undermining 27/01/2016 Resurvey 8
LW418 Undermined 10/02/2016 Resurvey 9
LW418 Undermined 8/3/2016 Resurvey 10
LW418 Undermined 6//04/2016 Resurvey 11
LW418 Areas 1, 2 6//04/2016 Resurvey 12
LW418 Undermined 10+11/05/2016 Resurvey 13
* Second survey
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Photos from the last survey of the features are presented in Table 29.
Comparison of Key Surface Features above Longwall 418 Table 29.
Sunnyside East Swamp
Baseline survey
LW418-2_Photo 033_2014_Feb04_IMG 033
Resurvey 12
LW418-2_Photo 033_2016_Apr 06_IMGP0013
Carne West Swamp
Baseline survey
LW418-1_Photo 046_2014_Feb02_IMG 0050
Resurvey 12
LW418-1_Photo 046_2016_Apr 06_IMGP0054
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Tracks
Baseline survey
LW418-1_Photo 004_2014_Feb02_IMG
0004
Resurvey 13
LW418-1_Photo 004_2016_May 6_IMGP0028
Rock Feature
Baseline
LW418-1_Photo 037_2014_Feb02_IMG
0041
Resurvey 12
LW418-1_Photo 037_2016_Apr 06_IMGP0107
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Subsidence Lines
Baseline
LW418-2_Photo 043_2014_Feb04_IMG 043
Resurvey 12
LW418-2_Photo 043_2016_Apr 06_IMGP0022
Photos are considered consistent with previous photographic records.
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6.13.2. Newnes Plateau Shrub swamps
Photographic monitoring sites have been established for each swamp overlying the SMP area.
Relevant to the extraction of Longwall 417 and 418 is Sunnyside East Swamp.
Table 30 summarises the photographic survey monitoring undertaken in reference to Sunnyside East
Swamp.
Sunnyside East Swamp photographic Monitoring Summary Table 30.
Date Photographed Resurvey Number
14/4/2009 Baseline
28-30/10/2009 Resurvey 1
21/5/2010 Resurvey 2
17/11/2010 Resurvey 3
24/5/2011 Resurvey 4
24/1/2012 Resurvey 5
25/7/2012 Resurvey 6
25/1/2013 Resurvey 7
3/4/2013 Resurvey 8
20/6/2013 Resurvey 9
19/9/2013 Resurvey 10
3/12/2013 Resurvey 11
15/1/2014 Resurvey 12
14/3/2014 Resurvey 13
22/4/2014 Resurvey 14
22/7/2014 Resurvey 15
27/10/2014 Resurvey 16
19/1/2015 Resurvey 17
16/4/2015 Resurvey 18
6/7/2015 Resurvey 19
2/10/2015 Resurvey 20
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Date Photographed Resurvey Number
28/01/2016 Resurvey 21
4/4/2016 Resurvey 22
The following images compare baseline to the last survey undertaken. The monitoring tool is used as
a visual tool and data collected is used in combination with other monitoring methodology e.g. flora,
groundwater, climatic data to assist in interpretation.
Comparison of Sunnyside East Swamp Photographic Monitoring Table 31.
Baseline Resurvey 22
Photo_003_2009_0414Image0049
SSES_Photo 003_2016_Apr04_IMGP0003
Photo_006_2009_0414Image0052
SSES_Photo 006_2016_Apr04_IMGP0007
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Photo_022_2009_0414ImageSSE_Stitch
2
SSES_Photo 022_2016_Apr04_IMGP0017-18
Photo_067_2009_0414Image2407
SSES_Photo 067_2016_Apr04_IMGP0066
Photo_073_2009_0414Image0104
SSES_Photo 073_2016_Apr04_IMGP0072
Photos are considered consistent with previous photographic records.
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Table 32 summarises the photographic survey monitoring undertaken in reference to Carne West
Swamp.
Carne West Swamp photographic Monitoring Summary Table 32.
Date Photographed Resurvey Number
24/11/2008 Baseline
22/12/2009 Resurvey 1
25/6/2010 Resurvey 2
25/3/2011 Resurvey 3
3/6/2011 Resurvey 4
25/10/2011 Resurvey 5
3/4/2012 Resurvey 6
30/10/2012 Resurvey 7
30/4/2013 Resurvey 8
11/12/2013 Resurvey 9
23/4/2014 Resurvey 10
23/7/2014 Resurvey 11
10/10/2014 Resurvey 12
16/1/2015 Resurvey 13
10/4/2015 Resurvey 14
8/7/2015 Resurvey 15
6/10/2015 Resurvey 16
17/01/2016 Resurvey 17
5//04/2016 Resurvey 18
The following images compare baseline to the last survey undertaken. The monitoring tool is used as
a visual tool and data collected is used in combination with other monitoring methodology e.g. flora,
groundwater, climatic data to assist in interpretation.
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Comparison of Carne Swamp Photographic Monitoring Table 33.
Baseline Resurvey 18
CWS_Photo_002_2008_1124Image0004
CWS_Photo_002_2016_Apr 5_IMGP0001
CWS_Photo_006_2008_1124Image0006
CWS_Photo_006_2016_Apr 5_IMGP0004
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CWS_Photo_013_2008_1124Image0013
CWS_Photo_013_2016_Apr 5_IMGP0013
CWS_Photo_020_2008_1124Image0020
CWS_Photo_020_2016_Apr 5_IMGP0020
CWS_Photo_048_2008_1124Image0065
CWS_Photo_048_2016_Apr 5_IMGP0049
Photos are considered consistent with previous photographic records.
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7. ADEQUECY, QUALITY AND EFFECTIVENESS
The adequacy, quality, effectiveness of the implemented management processes based on
monitoring and consultation is considered to be satisfactory to date.
There were no non-compliances with the conditions of the SMP approval during the reporting period.
8. PROPOSED MANAGEMENT ACTIONS
No TARP exceedances were triggered during the reporting period.
There are no outstanding management actions requiring an update.
9. CONCLUSIONS
Extraction of Longwall 418 commenced on the 22nd
of October 2015 and was completed on the 27th of
May 2016 with a total retreat of 2487m.
There have been no observed subsidence impacts, incidents or service difficulties during the retreat
of Longwall 418. Subsidence results have been within the predications.
During the reporting period observed rainfall on the Newnes Plateau remained significantly below the
long term average. A cumulative rainfall deficient therefore continues to be observed in the region.
Longer term climatic influences appear to be contributing to water monitoring data observations
(groundwater and surface water). This is supported by similar observations being made in reference
sites.
Data analysis demonstrates there have been no significant differences in habitat characteristics at
fauna monitoring sites. There has been no significant difference in fauna species richness values
within the SMP area. Threatened species continue to be recorded.
Flora observations made at trigger and reference sites support that cofounding environmental factors are active within the mining area.
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Appendix 1
Plans
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Appendix 2
Groundwater and
Surface Water
Report
Springvale Colliery
Castlereagh Highway
Lidsdale NSW 2790
PO Box 198